CN115929419A - An air turbine system and its operating method - Google Patents

Abstract

The invention provides an air turbine system and an operation method, including a compressed air source, which communicates with the inlet of the high-pressure air turbine through a high-pressure inlet pipe; The air supply pipe and the medium-pressure air supply pipe connected with the air inlet of the medium-pressure air turbine; the high-pressure air supply pipe is equipped with a high-pressure air supply valve, and the medium-pressure air supply pipe is equipped with a medium-pressure air supply valve; the high-pressure air supply pipe is equipped with a high-pressure An on-off valve and a high-pressure regulating valve; the exhaust port of the high-pressure air turbine is connected in parallel with a medium-pressure intake pipe connected with the intake port of the medium-pressure air turbine and a low-pressure intake pipe communicated with the intake port of the low-pressure air turbine; The air pipe is equipped with a medium-pressure on-off valve and a medium-pressure regulating valve; the low-pressure inlet pipe is equipped with a No. 1 low-pressure on-off valve, a low-pressure regulating valve and a No. 2 low-pressure on-off valve; The exhaust pipe communicates with the low-pressure intake pipe; the invention controls the connection relationship of each air turbine to ensure that the total output power remains unchanged.

Description

An air turbine system and its operating method

technical field

The invention belongs to the technical field of compressed air energy storage, and in particular relates to an air turbine system capable of adapting to wide-ranging changes in the pressure of an air compression source and an operating method thereof.

Background technique

Compressed air energy storage system is a new type of energy storage technology, which has the advantages of wide power range, long life, unlimited storage time, and environmental friendliness. It has become an important research direction of energy storage technology at present. The principle is to use excess electric energy to compress the air and store it in closed spaces such as salt caverns and high-pressure gas storage tanks during the low-peak period of electricity consumption. During the peak period of electricity consumption, the stored high-pressure air is used to drive the air turbine to generate power. to meet the electricity demand. Due to the limited compressed air that can be stored in confined spaces such as salt caverns and high-pressure gas storage tanks, during the work process of the air turbine, with the outflow of compressed air, the storage pressure will continue to decrease, resulting in a continuous decrease in the output power of the air turbine , which cannot meet the output requirements; therefore, for the compressed air energy storage system with limited gas storage capacity, how to ensure the stable output power of the air turbine is a technical problem to be solved urgently in this application.

Contents of the invention

In view of the above shortcomings of the prior art, the purpose of the present invention is to provide an air turbine system and its operating method that can adapt to a wide range of changes in the pressure of the air compression source. When the pressure of the air compression source changes, switch the high-pressure air turbine, The connection relationship between the medium-pressure air turbine and the low-pressure air turbine ensures that the sum of the output power of each air turbine remains constant.

To achieve the above and other related purposes, the present invention provides an air turbine system, comprising a compressed air source, a high-pressure air turbine, a medium-pressure air turbine and a low-pressure air turbine; The air inlet of the air turbine is connected; the high-pressure air inlet pipe is provided with a high-pressure air supply pipe and a medium-pressure air supply pipe in parallel; the high-pressure air supply pipe is connected with the air supply port of the high-pressure air turbine, and the high-pressure air supply pipe is provided with a high-pressure Air supply valve; the medium-pressure air supply pipe is connected with the air inlet of the medium-pressure air turbine, and the medium-pressure air supply pipe is provided with a medium-pressure air supply valve; the high-pressure air intake pipe is provided with a high-pressure on-off valve and a high-pressure Regulating valve, the air inlet of the high-pressure air supply pipe and the air inlet of the medium-pressure air supply pipe are both located between the high-pressure on-off valve and the high-pressure regulating valve; the exhaust port of the high-pressure air turbine is provided in parallel with a medium-pressure Inlet pipe and low-pressure air inlet pipe; the medium-pressure air inlet pipe is connected with the air inlet of the medium-pressure air turbine, and the medium-pressure air inlet pipe is provided with a medium-pressure on-off valve and a medium-pressure regulating valve; the low-pressure air inlet pipe It communicates with the air inlet of the low-pressure air turbine, and the low-pressure air inlet pipe is provided with No. 1 low-pressure on-off valve, low-pressure regulating valve and No. 2 low-pressure on-off valve in sequence along its flow direction; the exhaust port of the medium-pressure air turbine The medium-pressure exhaust pipe communicates with the low-pressure intake pipe, and the air outlet of the medium-pressure exhaust pipe is located between the low-pressure regulating valve and the No. 2 low-pressure on-off valve; the exhaust port of the low-pressure air turbine communicates with the atmosphere; According to the pressure drop of the compressed air source, the present invention adjusts each valve to control the connection relationship between the compressed air source, the high-pressure air turbine, the medium-pressure air turbine and the low-pressure air turbine, so that the sum of the output power of each air turbine constant.

Preferably, the air turbine system includes a medium-pressure heater and a low-pressure heater; the medium-pressure heater is arranged on the medium-pressure inlet pipe, and the low-pressure heater is arranged on the low-pressure The compressed air from the compressed air turbine and the low pressure air turbine is heated.

Preferably, the medium-pressure cylinder is a single-flow medium-pressure cylinder or a double-flow medium-pressure cylinder, which can be specifically determined according to the total flow rate of the compressed air source.

Preferably, the air turbine system includes a generator, and the high-pressure air turbine, the medium-pressure air turbine, the low-pressure air turbine and the generator are sequentially connected through couplings to form a series shafting system to ensure that the generated power of the generator remains constant.

Preferably, each air turbine is connected to a generator through a coupling to ensure that the sum of the generated power of each generator remains constant.

The present application also provides an operating method of an air turbine system, the operating method comprising the following steps:

When the pressure of the compressed air source is greater than the first preset pressure value, close the high-pressure air supply valve, medium-pressure air supply valve, No. 1 low-pressure on-off valve and low-pressure regulating valve, and open the high-pressure on-off valve, medium-pressure on-off valve, The high-pressure regulating valve, medium-pressure regulating valve, medium-pressure heater and low-pressure heater make the medium-pressure regulating valve fully open, and gradually increase the opening of the high-pressure regulating valve according to the pressure drop of the compressed air source, so that each air can The total power emitted by Ping remains unchanged;

When the pressure of the compressed air source is not greater than the first preset pressure value and greater than the second preset pressure value, open the high-pressure air supply valve so that the high-pressure regulating valve and the medium-pressure regulating valve are fully open, and according to the compressed air source Gradually increase the opening of the high-pressure air supply valve to keep the total power of each air turbine unchanged;

When the pressure of the compressed air source is not greater than the second preset pressure value and greater than the third preset pressure value, open the medium pressure air supply valve, so that the high pressure regulating valve, medium pressure regulating valve and high pressure air supply valve are in a fully open state , and gradually increase the opening of the medium-pressure air supply valve according to the pressure drop of the compressed air source, so that the total power from each air turbine remains unchanged;

When the pressure of the compressed air source is not greater than the third preset pressure value and greater than the fourth preset pressure value, open the No. 1 low-pressure on-off valve, and gradually decrease the middle Adjust the valve opening of the high-pressure air supply valve according to the pressure ratio between the inlet port of the high-pressure air turbine and the air supply port, and gradually increase the opening of the medium-pressure air supply valve according to the pressure drop of the compressed air source degree, so that the total power generated by each air turbine remains constant;

When the pressure of the compressed air source is not greater than the fourth preset pressure value, close the high-pressure air supply valve, medium-pressure regulating valve, medium-pressure on-off valve and medium-pressure heater, and gradually increase the pressure according to the pressure drop of the compressed air source. The opening of the pressure supplementary air valve until the medium pressure supplementary air valve is fully opened, so that the total power from each air turbine remains unchanged.

Preferably, the first preset pressure value is the opening pressure value of the high-pressure air supplement valve, the second preset pressure value is the opening pressure value of the medium-pressure air supplement valve, and the third preset pressure value is the opening pressure value of the impending blowing The critical pressure value, the fourth preset pressure value is the corresponding pressure value of the compressed air source when the medium and high pressure air turbines are switched from the series-parallel state to the parallel state.

As above, an air turbine system and operating method of the present invention have the following beneficial effects:

The present invention changes the connection relationship between the high-pressure air turbine, the medium-pressure air turbine and the low-pressure air turbine to overcome the problem of the decrease in the output power of the air turbine caused by the pressure drop of the compressed air source. At the same time of efficient operation, the total power output by each air turbine is always kept constant; because the invention has the ability to adapt to the pressure drop of the compressed air source, the gas storage volume of the compressed air energy storage system can be properly controlled, thereby effectively controlling the investment cost .

Description of drawings

FIG. 1 is a schematic diagram of an air turbine system according to an embodiment of the present invention.

Fig. 2 is the schematic diagram of the air turbine system of an embodiment in the present invention

Figure 3 is a flowchart of a method of operating an air turbine system.

High-pressure air turbine 1, medium-pressure air turbine 2, low-pressure air turbine 3, generator 4, high-pressure air intake pipe 5, high-pressure air supply pipe 5a, medium-pressure air supply pipe 5b, medium-pressure air intake pipe 6, low-pressure air intake pipe 7, Medium-pressure exhaust pipe 8, high-pressure on-off valve 9, high-pressure regulating valve 10, high-pressure air supply valve 11, medium-pressure air supply valve 12, medium-pressure regulating valve 13, medium-pressure on-off valve 14, medium-pressure heater 15, No. 1 low-pressure on-off valve 16, low-pressure regulating valve 17, low-pressure heater 18, and No. 2 low-pressure on-off valve 19.

Detailed ways

The implementation of the present invention will be illustrated by specific specific examples below, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

See Figures 1 through 3. It should be noted that the structures, proportions, sizes, etc. shown in the drawings attached to this specification are only used to match the content disclosed in the specification, for those who are familiar with this technology to understand and read, and are not used to limit the implementation of the present invention. Limiting conditions, so there is no technical substantive meaning, any modification of structure, change of proportional relationship or adjustment of size, without affecting the effect and purpose of the present invention, should still fall within the scope of the present invention. The disclosed technical content must be within the scope covered. At the same time, terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description and are not used to limit this specification. The practicable scope of the invention and the change or adjustment of its relative relationship shall also be regarded as the practicable scope of the present invention without any substantial change in the technical content.

Embodiment one

As shown in Figure 1, the present embodiment provides an air turbine system, including a compressed air source, a high-pressure air turbine 1, a medium-pressure air turbine 2, and a low-pressure air turbine 3; the high-pressure air turbine 1 has an air inlet , air supply port and exhaust port; the medium pressure air turbine 2 and the low pressure air turbine 3 both have an air inlet and an exhaust port; wherein, the air inlet of the high pressure air turbine 1 is connected to the compressed air source through the high pressure air inlet pipe 5 Communication; the high-pressure air intake pipe 5 is provided with a high-pressure on-off valve 9 and a high-pressure regulating valve 10, the high-pressure on-off valve 9 is used to connect or cut off the high-pressure air intake pipe 5, and the high-pressure regulating valve 10 is used to adjust the intake air entering the high-pressure air turbine 1 The flow rate of the port; the high-pressure air intake pipe 5 is provided with a high-pressure air supply pipe 5a and a medium-pressure air supply pipe 5b in parallel; the high-pressure air supply pipe 5a is connected with the air supply port of the high-pressure air turbine 1, and the medium-pressure air supply pipe 5b is connected with the medium-pressure air turbine 2 The air inlet of the high-pressure air supply pipe 5a is provided with a high-pressure air supply valve 11 for adjusting the flow rate of the air supply port entering the high-pressure air turbine 1, and the medium-pressure air supply pipe 5b is provided with a valve 11 for adjusting the air intake of the medium-pressure air turbine 2 The medium-pressure air supply valve 12 of the flow rate at the port; the exhaust port of the high-pressure air turbine 1 is divided into two branches, which are respectively the medium-pressure intake pipe 6 connected with the air inlet of the medium-pressure air turbine 2 and the medium-pressure air inlet pipe 6 connected with the low-pressure air turbine 3 The low-pressure intake pipe 7 connected to the air inlet; the medium-pressure intake pipe 6 is provided with a medium-pressure regulating valve 13 and a medium-pressure on-off valve 14, which respectively control the flow and on-off of the medium-pressure intake pipe 6; the low-pressure intake pipe 7 is The flow direction is provided with a No. 1 low-pressure on-off valve 16, a low-pressure regulating valve 17 and a No. 2 low-pressure on-off valve 19, which are used to control the on-off and flow of the low-pressure intake pipe 7; the outlet of the medium-pressure air turbine 2 is set There is a medium-pressure exhaust pipe 8 communicating with the low-pressure intake pipe 7, and the gas outlet of the medium-pressure exhaust pipe 8 is located between the low-pressure regulating valve 17 and No. 2 low-pressure on-off valve 19; in this embodiment, the medium-pressure regulating valve 13 is preferably arranged downstream of the medium pressure on-off valve 14 .

By controlling the state of each valve, the air turbines in the air turbine system can be in different connection states, which have the following five connection states in total:

State 1: Close the high-pressure air supply valve 11, the medium-pressure air supply valve 12, the No. 1 low-pressure on-off valve 16 and the low-pressure regulating valve 17, open the high-pressure on-off valve 9 and the medium-pressure on-off valve 14, and make the medium-pressure regulating valve 13 It is in the fully open state (that is, the state with the largest valve opening), and gradually increases the valve opening of the high-pressure regulating valve 10 according to the pressure drop of the compressed air source; at this time, the high-pressure air turbine 1, the medium-pressure air turbine 2 and the The low-pressure air turbine 3 forms a series combination, so that the compressed air from the compressed air source enters the high-pressure air turbine 1 through the high-pressure inlet pipe 5 to perform work, and the exhaust gas of the high-pressure air turbine 1 enters the medium-pressure air turbine 2 to perform work, and the medium-pressure air turbine The exhaust from level 2 enters the low-pressure air turbine 3 to do work, and the exhaust from the low-pressure air turbine 3 is discharged into the atmosphere. Ensure that the post-valve pressure of the high-pressure regulating valve 10 is always kept at the flow design pressure, and the flow rate entering each air turbine is also kept at the design flow rate, so as to prevent the turbines from overheating and ensure that the total output power of each air turbine remains unchanged.

State 2: Close the medium-pressure air supply valve 12, No. 1 low-pressure on-off valve 16 and low-pressure regulating valve 17, open the high-pressure on-off valve 9 and the medium-pressure on-off valve 14, so that the medium-pressure regulating valve 13 and the high-pressure regulating valve 10 are at Fully open state (that is, the state with the largest valve opening), and gradually increase the valve opening of the high-pressure air supply valve 11 according to the pressure drop of the compressed air source; at this time, the high-pressure air turbine 1, the medium-pressure air turbine 2 and the The low-pressure air turbine 3 still forms a series combination, so that the compressed air from the compressed air source enters the high-pressure air turbine 1 through the high-pressure inlet pipe 5 and the high-pressure air supply pipe 5a to perform work, and the exhaust gas of the high-pressure air turbine 1 enters the medium-pressure air turbine 2 work, the exhaust from the medium pressure air turbine 2 enters the low pressure air turbine 3 to perform work, and the exhaust from the low pressure air turbine 3 is discharged into the atmosphere; during this process, although the pressure of the compressed air source continues to drop, due to the The flow rate of each air turbine continues to rise, making up for the insufficient output power caused by the drop in compressed air pressure, and ensuring that the total output power of each air turbine remains unchanged.

State three: Close the No. 1 low-pressure on-off valve 16 and low-pressure regulating valve 17, open the high-pressure on-off valve 9 and the medium-pressure on-off valve 14, so that the medium-pressure regulating valve 13, high-pressure regulating valve 10 and high-pressure air supply valve 11 are all at Fully open state (that is, the state with the largest valve opening), and gradually increase the valve opening of the medium-pressure air supply valve 12 according to the pressure drop of the compressed air source; at this time, the high-pressure air turbine 1 and the medium-pressure air turbine 2 A series-parallel combination is formed (i.e., both are connected in parallel and connected in series), and then the series-parallel combination is connected in series with the low-pressure air turbine 3, so that part of the compressed air from the compressed air source enters through the high-pressure intake pipe 5 and the high-pressure air supply pipe 5a. The high-pressure air turbine 1 does work, and part of the compressed air from the compressed air source enters the medium-pressure air turbine 2 through the medium-pressure air supply pipe 5b together with the exhaust gas of the high-pressure air turbine 1 to perform work, and the exhaust gas of the medium-pressure air turbine 2 enters the low-pressure The air turbine 3 does work, and the exhaust gas of the low-pressure air turbine 3 is discharged into the atmosphere; during this process, although the pressure of the compressed air source continues to drop, the flow rate into the medium-pressure air turbine and the low-pressure air turbine is still The continuous rise makes up for the insufficient output power caused by the drop of compressed air pressure, and ensures that the total output power of each air turbine remains unchanged.

State 4: Open the high-pressure on-off valve 9, the medium-pressure on-off valve 14 and the No. 1 low-pressure on-off valve 16, and gradually reduce the valve of the medium-pressure regulating valve 13 while gradually increasing the opening of the low-pressure regulating valve 17 To avoid sudden pressure changes, gradually increase the opening of the medium-pressure air supply valve 12 according to the pressure drop of the compressed air source, and at the same time adjust the high-pressure air supply valve according to the pressure ratio between the air inlet of the high-pressure air turbine 1 and the air supply port The valve opening of 11 is used to avoid the blowing phenomenon in the passage section before the air supply point caused by the low pressure of the air inlet of the high-pressure air turbine 1, and to improve the operation safety of the high-pressure air turbine 1; at this time, the high-pressure air turbine 1 Turbine 1 and medium-pressure air turbine 2 form a series-parallel combination (that is, they are arranged in parallel and connected in series), and high-pressure air turbine 1 and medium-pressure air turbine 2 are respectively connected in series with low-pressure air turbine 3 , so that part of the compressed air from the compressed air source enters the high-pressure air turbine 1 through the high-pressure intake pipe 5 and the high-pressure air supply pipe 5a to perform work, and part of the compressed air from the compressed air source passes through the medium-pressure air supply pipe 5b and a part of the high-pressure air turbine 1 is exhausted Enter the medium pressure air turbine 2 together to do work, the exhaust of the medium pressure air turbine 2 and another part of the exhaust of the high pressure air turbine 1 enter the low pressure air turbine 3 together to do work, and the exhaust of the low pressure air turbine 3 is discharged into the atmosphere During this process, although the pressure of the compressed air source continues to drop, the flow into the medium-pressure air turbine and the low-pressure air turbine continues to rise, making up for the insufficient output power caused by the drop in compressed air pressure. Make sure that the total power output by each air turbine remains constant.

State five: close the high-pressure air supply valve 11, the medium-pressure regulating valve 13 and the medium-pressure on-off valve 14, open the high-pressure on-off valve 9, the No. 1 low-pressure on-off valve 16 and the low-pressure regulating valve 17, and according to the pressure of the compressed air source The descending amount gradually increases the opening degree of the medium-pressure air supply valve 12; at this time, the high-pressure air turbine 1 and the medium-pressure air turbine 2 form a parallel combination, and the parallel combination is connected in series with the low-pressure air turbine 3, so that the compressed air source Part of the compressed air enters the high-pressure air turbine 1 through the high-pressure inlet pipe 5 to do work, and part of the compressed air from the compressed air source enters the medium-pressure air turbine 2 through the medium-pressure air supply pipe 5b to perform work, and the exhaust and high-pressure air of the medium-pressure air turbine 2 The exhaust from turbine 1 enters the low-pressure air turbine 3 together to do work, and the exhaust from the low-pressure air turbine 3 is discharged into the atmosphere; The flow rate of Pinghe low-pressure air turbines is still rising, making up for the insufficient output power caused by the drop in compressed air pressure, and ensuring that the total output power of each air turbine remains unchanged.

Further, the medium-pressure inlet pipe 6 is provided with a medium-pressure heater 15, and the low-pressure inlet pipe 7 is provided with a low-pressure inlet pipe 17. The medium-pressure heater 15 is located upstream of the medium-pressure on-off valve 14, and is used to The exhaust gas of the intake pipe 6 is heated; the low-pressure heater 18 is located between the outlet of the medium-pressure exhaust pipe 8 and the No. 2 low-pressure on-off valve 19 for heating the exhaust gas entering the low-pressure intake pipe 7 .

Further, as shown in Figure 1, the air turbine system includes a generator, high-pressure air turbine 1, medium-pressure air turbine 2, low-pressure air turbine 3 and generator 4 are sequentially connected through couplings to form a series shafting system.

Embodiment two

As shown in Figure 2, the difference between this embodiment and Embodiment 1 lies in the number and arrangement of generators 4; the number of generators 4 in this embodiment is three, and the three generators 4 are separated by couplings. It is connected with high pressure air turbine 1, medium pressure air turbine 2 and low pressure air turbine 3.

Embodiment Three

The difference between the present embodiment and the first embodiment is only the structural form and number of the medium pressure cylinder 2 and the low pressure cylinder 3. Specifically, there are the following four schemes:

Scheme 1: One medium-pressure cylinder 2 and one low-pressure cylinder 3 are respectively installed, and medium-pressure cylinder 2 is a single-flow medium-pressure cylinder, and low-pressure cylinder 3 is a single-flow low-pressure cylinder; scheme 1 is suitable for compressed air sources with small flow rates.

Scheme 2: One medium-pressure cylinder 2 and one low-pressure cylinder 3 are respectively installed, and the medium-pressure cylinder 2 is a single-flow medium-pressure cylinder, and the low-pressure cylinder 3 is a double-flow low-pressure cylinder; scheme 2 is suitable for compressed air sources with normal flow rates.

Scheme 3: One medium-pressure cylinder 2 and one low-pressure cylinder 3 are respectively installed, and the medium-pressure cylinder 2 is a double-flow medium-pressure cylinder, and the low-pressure cylinder 3 is a double-flow low-pressure cylinder; scheme 3 is suitable for a compressed air source with a large flow rate.

Solution 4: Set up one medium pressure cylinder 2 and multiple low pressure cylinders 3, and the medium pressure cylinder 2 is a single-flow medium pressure cylinder, and the low pressure cylinder 3 is a single flow low pressure cylinder; multiple low pressure cylinders 3 are connected in series and connected to each other. A reheater is provided between two adjacent low-pressure cylinders 3; scheme 4 is suitable for compressed air sources with higher inlet pressure and lower temperature.

Embodiment Four

As shown in Figure 3, this embodiment provides an operation method of an air turbine system, requiring the air turbine system of Embodiment 1 or 2 to output a power sum of 30MW within the pressure range of 10Mpa to 3MPa of the compressed air source; The run method includes the following steps:

S1. When the pressure of the compressed air source is greater than the first preset pressure value, close the high-pressure air supply valve 11, the medium-pressure air supply valve 12, the No. 1 low-pressure on-off valve 16 and the low-pressure regulating valve 17, and open the high-pressure on-off valve 9, Medium-pressure on-off valve 14, high-pressure regulating valve 10, medium-pressure regulating valve 13, No. 2 low-pressure on-off valve 19, medium-pressure heater 15 and low-pressure heater 18 make medium-pressure regulating valve 13 fully open, and according to The pressure drop of the compressed air source gradually increases the opening of the high-pressure regulating valve 10, so that the total power sent by each air turbine remains unchanged;

Specifically, the first preset pressure value is the opening pressure value of the high-pressure air supply valve 11, which is 8.11MPa; under this step, the pressure of the compressed air source is always greater than the opening pressure value of the high-pressure air supply valve 11, ensuring high pressure The air supply valve 11 is always in the closed state; when the pressure of the compressed air source drops to 8.11MPa, the high pressure regulating valve 10 needs to be in the fully open state (that is, the valve opening is the largest).

Under this step, the high-pressure air turbine 1, the medium-pressure air turbine 2 and the low-pressure air turbine 3 form a series combination, so that the compressed air from the compressed air source enters the high-pressure air turbine 1 through the high-pressure inlet pipe 5 to perform work, and the high-pressure air turbine Exhaust from level 1 enters medium-pressure air turbine 2 to do work, exhaust from medium-pressure air turbine 2 enters low-pressure air turbine 3 to perform work, and exhaust from low-pressure air turbine 3 is discharged into the atmosphere.

S2. When the pressure of the compressed air source is not greater than the first preset pressure value and greater than the second preset pressure value, open the high-pressure air supply valve 11, so that the high-pressure regulating valve 10 and the medium-pressure regulating valve 13 are in a fully open state, And gradually increase the opening of the high-pressure air supply valve 11 according to the pressure drop of the compressed air source, so that the total power sent by each air turbine remains unchanged;

Specifically, the second preset pressure value is the opening pressure value of the medium-pressure air supplement valve 12, which is 7.2MPa; under this step, the pressure of the compressed air source is greater than 7.2MPa and not greater than 8.11Mpa, so that the high-pressure supplementary air The air valve 11 is opened, and the medium-pressure air supply valve 12 is still closed; when the pressure of the compressed air source drops to 7.2MPa, the high-pressure air supply valve 11 needs to be in a fully open state.

Under this step, the high-pressure air turbine 1, the medium-pressure air turbine 2 and the low-pressure air turbine 3 still form a series combination, so that the compressed air from the compressed air source enters the high-pressure air turbine through the high-pressure inlet pipe 5 and the high-pressure air supply pipe 5a 1 does work, the exhaust gas of high pressure air turbine 1 enters medium pressure air turbine 2 to do work, the exhaust gas of medium pressure air turbine 2 enters low pressure air turbine 3 to do work, and the exhaust gas of low pressure air turbine 3 is discharged into the atmosphere;

S3. When the pressure of the compressed air source is not greater than the second preset pressure value and greater than the third preset pressure value, open the medium pressure air supply valve 12 to make the high pressure regulating valve 10, the medium pressure regulating valve 13 and the high pressure supply air The valve 11 is fully open, and gradually increases the opening of the medium-pressure air supply valve 12 according to the pressure drop of the compressed air source, so that the total power of each air turbine remains unchanged;

Specifically, the third preset pressure value is the critical pressure value of the blowing phenomenon in the flow section before and after the air supply point in the high-pressure air turbine 1, and the pressure value is 5.3MPa; under this step, the pressure of the compressed air source Greater than 5.3MPa, and not greater than 7.2Mpa, so that both the high-pressure air supply valve 11 and the medium-pressure air supply valve 12 can be opened.

Under this step, the high-pressure air turbine 1 and the medium-pressure air turbine 2 form a series-parallel combination (that is, they are arranged in parallel and connected in series), and then the series-parallel combination is connected in series with the low-pressure air turbine 3, so that the compression Part of the compressed air from the air source enters the high-pressure air turbine 1 through the high-pressure intake pipe 5 and the high-pressure air supply pipe 5a to do work, and part of the compressed air from the compressed air source enters the medium-pressure air turbine 1 through the medium-pressure air supply pipe 5b together with the exhaust gas from the high-pressure air turbine 1. The air turbine 2 does work, the exhaust from the medium-pressure air turbine 2 enters the low-pressure air turbine 3 to perform work, and the exhaust from the low-pressure air turbine 3 is discharged into the atmosphere.

S4. When the pressure of the compressed air source is not greater than the third preset pressure value and greater than the fourth preset pressure value, open the No. 1 low-pressure on-off valve 16, and in the process of slowly increasing the opening of the low-pressure regulating valve 17, Gradually reduce the valve opening of the medium-pressure regulating valve 13, and adjust the valve opening of the high-pressure air supply valve 11 according to the pressure ratio between the air inlet of the high-pressure air turbine 1 and the air supply port, and at the same time gradually reduce the pressure drop of the compressed air source. Increase the opening degree of the medium-pressure air supply valve 12, so that the total power sent by each air turbine remains unchanged;

Specifically, the fourth preset pressure value is the pressure of the compressed air source corresponding to when the valve opening of the medium pressure regulating valve 13 is adjusted to fully closed, and this value is 5MPa; when the pressure of the compressed air source drops to 5.3MPa, the high pressure In air turbine 1, the expansion ratio of the flow-through section before the air supply point has reached the blast critical value (that is, the ratio of the inlet pressure of the high-pressure air turbine to the air supply port pressure reaches the blast critical value), if the pressure of the compressed air source Continued decline will cause the ratio of the air inlet pressure of the high-pressure air turbine 1 to the air supply port pressure to be lower than the blowing critical value, causing the high-pressure air turbine to produce a blowing phenomenon. In order to overcome this defect, this step is based on the real-time The pressure ratio between the air inlet and the air supply port of level 1 adjusts the valve opening of the high-pressure air supply valve 11 (that is, the pressure of the air intake port increases and the pressure of the air supply port decreases), so as to ensure the pressure ratio between the air intake port of the high-pressure air turbine 1 and the air supply port Always not less than the blast threshold.

Under this step, the high-pressure air turbine 1 and the medium-pressure air turbine 2 form a series-parallel combination (that is, they are arranged in parallel and connected in series), and the high-pressure air turbine 1 and the medium-pressure air turbine 2 are respectively It is connected in series with the low-pressure air turbine 3, so that part of the compressed air from the compressed air source enters the high-pressure air turbine 1 through the high-pressure inlet pipe 5 and the high-pressure air supply pipe 5a to perform work, and part of the compressed air from the compressed air source passes through the medium-pressure air supply pipe 5b and the high-pressure air A part of the exhaust from turbine 1 enters the medium-pressure air turbine 2 to do work together, and the exhaust from the medium-pressure air turbine 2 and the other part of the exhaust from the high-pressure air turbine 1 enter the low-pressure air turbine 3 to do work together, and the low-pressure air turbine 3 exhaust into the atmosphere.

S5. When the pressure of the compressed air source is not greater than the fourth preset pressure value, close the medium pressure on-off valve 14, the medium pressure regulating valve 13, the high pressure air supply valve 11 and the medium pressure heater 15, and according to the pressure of the compressed air source The amount of pressure drop gradually increases the opening of the medium-pressure air supply valve 12 until the medium-pressure air supply valve 12 is fully opened, so that the total power from each air turbine remains unchanged.

When the pressure value of the compressed air source drops to 3MPa, the medium-pressure air supply valve 12 is fully opened, and the air supply cannot be continued, indicating that the energy release mode is over.

Under this step, the high-pressure air turbine 1 and the medium-pressure air turbine 2 form a parallel combination, and the parallel combination is connected in series with the low-pressure air turbine 3, so that part of the compressed air from the compressed air source enters the high-pressure air turbine through the high-pressure intake pipe 5 Level 1 does work, a part of the compressed air from the compressed air source enters the medium-pressure air turbine 2 through the medium-pressure air supply pipe 5b to perform work, and the exhaust of the medium-pressure air turbine 2 and the exhaust of the high-pressure air turbine 1 enter the low-pressure air turbine together 3 works, and the exhaust gas of the low-pressure air turbine 3 is discharged into the atmosphere.

Embodiment five

As shown in Figure 3, this embodiment provides an operating method for an air turbine system, requiring the air turbine system of Embodiment 1 or 2 to output a power sum of 100 MW within the pressure range of 17Mpa to 5MPa of the compressed air source; The run method includes the following steps:

S1. When the pressure of the compressed air source is greater than the first preset pressure value, close the high-pressure air supply valve 11, the medium-pressure air supply valve 12, the No. 1 low-pressure on-off valve 16 and the low-pressure regulating valve 17, and open the high-pressure on-off valve 9, Medium-pressure on-off valve 14, high-pressure regulating valve 10, medium-pressure regulating valve 13, No. 2 low-pressure on-off valve 19, medium-pressure heater 15 and low-pressure heater 18 make medium-pressure regulating valve 13 fully open, and according to The pressure drop of the compressed air source gradually increases the opening of the high-pressure regulating valve 10, so that the total power sent by each air turbine remains unchanged;

Specifically, the first preset pressure value is the opening pressure value of the high-pressure air supply valve 11, which is 15.16 MPa; under this step, the pressure of the compressed air source is always greater than the opening pressure value of the high-pressure air supply valve 11, ensuring high pressure The air supplement valve 11 is always in the closed state; when the pressure of the compressed air source drops to 15.16MPa, the high-pressure regulating valve 10 needs to be in the fully open state (that is, the valve opening is the largest).

Under this step, the high-pressure air turbine 1, the medium-pressure air turbine 2 and the low-pressure air turbine 3 form a series combination, so that the compressed air from the compressed air source enters the high-pressure air turbine 1 through the high-pressure inlet pipe 5 to perform work, and the high-pressure air turbine Exhaust from level 1 enters medium-pressure air turbine 2 to do work, exhaust from medium-pressure air turbine 2 enters low-pressure air turbine 3 to perform work, and exhaust from low-pressure air turbine 3 is discharged into the atmosphere.

S2. When the pressure of the compressed air source is not greater than the first preset pressure value and greater than the second preset pressure value, open the high-pressure air supply valve 11, so that the high-pressure regulating valve 10 and the medium-pressure regulating valve 13 are in a fully open state, And gradually increase the opening of the high-pressure air supply valve 11 according to the pressure drop of the compressed air source, so that the total power sent by each air turbine remains unchanged;

Specifically, the second preset pressure value is the opening pressure value of the medium-pressure air supplement valve 12, which is 13.5MPa; under this step, the pressure of the compressed air source is greater than 13.5MPa and not greater than 15.16Mpa, so that the high-pressure supplementary air The air valve 11 is opened, and the medium-pressure air supply valve 12 is still closed; when the pressure of the compressed air source drops to 13.5MPa, the high-pressure air supply valve 11 needs to be in a fully open state.

Under this step, the high-pressure air turbine 1, the medium-pressure air turbine 2 and the low-pressure air turbine 3 still form a series combination, so that the compressed air from the compressed air source enters the high-pressure air turbine through the high-pressure inlet pipe 5 and the high-pressure air supply pipe 5a 1 does work, the exhaust gas of high pressure air turbine 1 enters medium pressure air turbine 2 to do work, the exhaust gas of medium pressure air turbine 2 enters low pressure air turbine 3 to do work, and the exhaust gas of low pressure air turbine 3 is discharged into the atmosphere;

S3. When the pressure of the compressed air source is not greater than the second preset pressure value and greater than the third preset pressure value, open the medium pressure air supply valve 12 to make the high pressure regulating valve 10, the medium pressure regulating valve 13 and the high pressure supply air The valve 11 is fully open, and gradually increases the opening of the medium-pressure air supply valve 12 according to the pressure drop of the compressed air source, so that the total power of each air turbine remains unchanged;

Specifically, the third preset pressure value is the critical pressure value of the blowing phenomenon that is about to occur in the flow section before the gas supply point in the high pressure air turbine 1, and the pressure value is 8.7MPa; under this step, the pressure of the compressed air source Greater than 8.7MPa, and not greater than 13.5Mpa, so that both the high-pressure air supply valve 11 and the medium-pressure air supply valve 12 can be opened.

Under this step, the high-pressure air turbine 1 and the medium-pressure air turbine 2 form a series-parallel combination (that is, they are arranged in parallel and connected in series), and then the series-parallel combination is connected in series with the low-pressure air turbine 3, so that the compression Part of the compressed air from the air source enters the high-pressure air turbine 1 through the high-pressure intake pipe 5 and the high-pressure air supply pipe 5a to do work, and part of the compressed air from the compressed air source enters the medium-pressure air turbine 1 through the medium-pressure air supply pipe 5b together with the exhaust gas from the high-pressure air turbine 1. The air turbine 2 does work, the exhaust from the medium-pressure air turbine 2 enters the low-pressure air turbine 3 to perform work, and the exhaust from the low-pressure air turbine 3 is discharged into the atmosphere.

S4. When the pressure of the compressed air source is not greater than the third preset pressure value and greater than the fourth preset pressure value, open the No. 1 low-pressure on-off valve 16, and in the process of slowly increasing the opening of the low-pressure regulating valve 17, Gradually reduce the valve opening of the medium-pressure regulating valve 13, and adjust the valve opening of the high-pressure air supply valve 11 according to the pressure ratio between the air inlet of the high-pressure air turbine 1 and the air supply port, and at the same time gradually reduce the pressure drop of the compressed air source. Increase the opening degree of the medium-pressure air supply valve 12, so that the total power sent by each air turbine remains unchanged;

Specifically, the fourth preset pressure value is the pressure of the compressed air source corresponding to when the valve opening of the medium pressure regulating valve 13 is adjusted to the minimum opening, and this value is 8.4MPa; when the pressure of the compressed air source drops to 8.4MPa , the expansion ratio of the flow-through section before the gas supply point in high pressure air turbine 1 has reached the blast critical value (that is, the ratio of the inlet pressure of the high pressure air turbine to the air supply port pressure reaches the blast critical value), if the compressed air source If the pressure continues to drop, it will cause the ratio of the air inlet pressure of the high pressure air turbine 1 to the pressure of the air supply port to be lower than the critical value of the blowing to produce a blowing phenomenon. In order to overcome this defect, this step is carried out according to the high pressure air turbine 1 in real time The pressure ratio between the air port and the air supply port adjusts the valve opening of the high-pressure air supply valve 11 (even if the pressure at the air inlet increases and the pressure at the air supply port decreases), to ensure that the pressure ratio between the air inlet of the high-pressure air turbine 1 and the air supply port is always not less than Blast threshold.

Under this step, the high-pressure air turbine 1 and the medium-pressure air turbine 2 form a series-parallel combination (that is, they are arranged in parallel and connected in series), and the high-pressure air turbine 1 and the medium-pressure air turbine 2 are respectively It is connected in series with the low-pressure air turbine 3, so that part of the compressed air from the compressed air source enters the high-pressure air turbine 1 through the high-pressure inlet pipe 5 and the high-pressure air supply pipe 5a to perform work, and part of the compressed air from the compressed air source passes through the medium-pressure air supply pipe 5b and the high-pressure air A part of the exhaust from turbine 1 enters the medium-pressure air turbine 2 to do work together, and the exhaust from the medium-pressure air turbine 2 and the other part of the exhaust from the high-pressure air turbine 1 enter the low-pressure air turbine 3 to do work together, and the low-pressure air turbine 3 exhaust into the atmosphere.

S5. When the pressure of the compressed air source is not greater than the fourth preset pressure value, close the medium pressure regulating valve 13, the medium pressure on-off valve 14, the high pressure air supply valve 11 and the medium pressure heater 15, and according to the pressure of the compressed air source The amount of pressure drop gradually increases the opening of the medium-pressure air supply valve 12 until the medium-pressure air supply valve 12 is fully opened, so that the total power from each air turbine remains unchanged.

When the pressure value of the compressed air source drops to 5MPa, the medium-pressure air supply valve 12 is fully opened, and the air supply cannot be continued, indicating that the energy release mode is over.

Under this step, the high-pressure air turbine 1 and the medium-pressure air turbine 2 form a parallel combination, and the parallel combination is connected in series with the low-pressure air turbine 3, so that part of the compressed air from the compressed air source enters the high-pressure air turbine through the high-pressure intake pipe 5 Level 1 does work, a part of the compressed air from the compressed air source enters the medium-pressure air turbine 2 through the medium-pressure air supply pipe 5b to perform work, and the exhaust of the medium-pressure air turbine 2 and the exhaust of the high-pressure air turbine 1 enter the low-pressure air turbine together 3 works, and the exhaust gas of the low-pressure air turbine 3 is discharged into the atmosphere.

The above-mentioned embodiments only illustrate the principles and effects of the present invention, but are not intended to limit the present invention. Anyone skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical ideas disclosed in the present invention should still be covered by the claims of the present invention.

Claims (7)

1. An air turbine system comprising a compressed air source, a high pressure air turbine, an intermediate pressure air turbine and a low pressure air turbine; the compressed air source is communicated with an air inlet of the high-pressure air turbine through a high-pressure air inlet pipe; the high-pressure air inlet pipe is provided with a high-pressure air supplementing pipe and a medium-pressure air supplementing pipe in parallel; the high-pressure air supplementing pipe is communicated with an air supplementing port of the high-pressure air turbine, and a high-pressure air supplementing valve is arranged on the high-pressure air supplementing pipe; the medium-pressure air supplementing pipe is communicated with an air inlet of the medium-pressure air turbine, and a medium-pressure air supplementing valve is arranged on the medium-pressure air supplementing pipe; the high-pressure air inlet pipe is provided with a high-pressure on-off valve and a high-pressure regulating valve, and an air inlet of the high-pressure air supplementing pipe and an air inlet of the medium-pressure air supplementing pipe are both positioned between the high-pressure on-off valve and the high-pressure regulating valve; a middle-pressure air inlet pipe and a low-pressure air inlet pipe are arranged at the exhaust port of the high-pressure air turbine in parallel; the medium-pressure air inlet pipe is communicated with an air inlet of the medium-pressure air turbine, and a medium-pressure on-off valve and a medium-pressure regulating valve are arranged on the medium-pressure air inlet pipe; the low-pressure air inlet pipe is communicated with an air inlet of the low-pressure air turbine, and a first low-pressure on-off valve, a low-pressure regulating valve and a second low-pressure on-off valve are sequentially arranged on the low-pressure air inlet pipe along the flowing direction of the low-pressure air inlet pipe; an air outlet of the medium-pressure air turbine is communicated with a low-pressure air inlet pipe through a medium-pressure exhaust pipe, and an air outlet of the medium-pressure exhaust pipe is positioned between a low-pressure regulating valve and a second low-pressure on-off valve; the exhaust port of the low pressure air turbine is in communication with the atmosphere.

2. An air turbine system according to claim 1, wherein said air turbine system includes a medium pressure heater and a low pressure heater; the medium-pressure heater is arranged on the medium-pressure air inlet pipe, and the low-pressure heater is arranged on the low-pressure air inlet pipe.

3. An air turbine system according to claim 1 or 2, wherein said intermediate pressure cylinder is a single flow intermediate pressure cylinder or a double flow intermediate pressure cylinder.

4. The air turbine system according to claim 1 or 2, wherein the air turbine system includes a generator, and the high-pressure air turbine, the intermediate-pressure air turbine, the low-pressure air turbine, and the generator are sequentially coupled by a coupling to form a tandem shafting.

5. An air turbine system according to claim 1 or 2, wherein each air turbine is coupled to an electrical generator by a coupling.

6. A method of operating an air turbine system as claimed in claim 2, wherein the method of operation comprises the steps of:

when the pressure of the compressed air source is greater than a first preset pressure value, closing the high-pressure air supplementing valve, the medium-pressure air supplementing valve, the first low-pressure on-off valve and the low-pressure regulating valve, opening the high-pressure on-off valve, the medium-pressure regulating valve, the second low-pressure on-off valve, the medium-pressure heater and the low-pressure heater, enabling the medium-pressure regulating valve to be in a full-open state, gradually increasing the opening degree of the high-pressure regulating valve according to the pressure reduction of the compressed air source, and keeping the total power emitted by each air turbine unchanged;

when the pressure of the compressed air source is not more than the first preset pressure value and is more than the second preset pressure value, opening the high-pressure air compensating valve to enable the high-pressure regulating valve and the medium-pressure regulating valve to be in a full-open state, and gradually increasing the opening of the high-pressure air compensating valve according to the pressure reduction of the compressed air source to enable the total power emitted by each air turbine to be kept unchanged;

when the pressure of the compressed air source is not more than the second preset pressure value and is more than a third preset pressure value, opening the medium-pressure air compensating valve to enable the high-pressure regulating valve, the medium-pressure regulating valve and the high-pressure air compensating valve to be in a fully open state, and gradually increasing the opening of the medium-pressure air compensating valve according to the pressure reduction of the compressed air source to enable the total power emitted by each air turbine to be kept unchanged;

when the pressure of the compressed air source is not more than a third preset pressure value and is more than a fourth preset pressure value, opening a first low-pressure on-off valve, slowly increasing the opening of the low-pressure regulating valve, gradually reducing the opening of the medium-pressure regulating valve, regulating the opening of the high-pressure air compensating valve according to the pressure ratio of the air inlet and the air compensating port of the high-pressure air turbine, and gradually increasing the opening of the medium-pressure air compensating valve according to the pressure reduction of the compressed air source to keep the total power emitted by each air turbine unchanged;

and when the pressure of the compressed air source is not more than the fourth preset pressure value, closing the high-pressure air compensating valve, the medium-pressure on-off valve, the medium-pressure regulating valve and the medium-pressure heater, and gradually increasing the opening of the medium-pressure air compensating valve according to the pressure reduction of the compressed air source until the medium-pressure air compensating valve is fully opened, so that the total power generated by each air turbine is kept unchanged.

7. The operation method according to claim 6, wherein the first preset pressure value is an opening pressure value of the high-pressure air compensation valve, the second preset pressure value is an opening pressure value of the medium-pressure air compensation valve, the third preset pressure value is a critical pressure value of the impending air blast, and the fourth preset pressure value is a pressure value of a corresponding compressed air source when the medium-pressure air turbine and the high-pressure air turbine are switched from a series-parallel state to a parallel state.

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