WO2017084137A1

WO2017084137A1 - Auxiliary converter device

Info

Publication number: WO2017084137A1
Application number: PCT/CN2015/097499
Authority: WO
Inventors: 王乾; 董启政; 王奔; 解鹏; 蒋学君; 刘峰东; 宜雷; 丁巧娅; 卫鹏; 李晶; 赵华
Original assignee: 永济新时速电机电器有限责任公司
Priority date: 2015-11-18
Filing date: 2015-12-15
Publication date: 2017-05-26
Also published as: CN105471272A

Abstract

An auxiliary converter device, comprising an auxiliary converter unit (1) connected between a three-phase alternating-current power supply and the ground. The auxiliary converter unit (1) is connected with an auxiliary control unit (6); and the auxiliary converter unit (1) comprises multiple auxiliary converters (2) that are mutually connected in parallel. The auxiliary converter device measures the value of a grounding current flowing through a grounding resistor unit (4) and sends the value to the auxiliary control unit (6) for analytical treatment; when the analysis result indicates that the value exceeds a preset threshold, it is determined that a grounding fault occurs to the auxiliary converters (2), the operation of the circuit can be stopped, and the fault is processed. In this way, a grounding fault can be accurately and quickly determined and processed, and operation safety and reliability of an electric locomotive can be effectively ensured.

Description

Auxiliary converter

Technical field

The invention relates to a flow conversion device for a railway vehicle, and in particular to an auxiliary flow conversion device.

Background technique

With the continuous advancement of science and technology, transportation is becoming more and more convenient. At present, many cities have built many subway lines in order to save construction costs and beautify the urban environment. With the increasing number of subway lines, the number of people taking the subway is also coming. The more this, the higher the overall performance of the subway, which, especially for the electric drive system to control the subway line, the electric drive system and the safety of the railway vehicle are closely related.

Because the electric drive system of rail transit has the characteristics of high voltage and high current, ensuring the normal operation of the drive system is the premise to ensure the reliable operation of the locomotive; the main circuit may occur due to cable aging, vibration and friction during the operation of the electric locomotive. Ground. In general, a little grounding will not cause any harm, and will not have much impact on the normal operation of the system. However, if two or more points are grounded, a large short-circuit current may be generated, resulting in an electric drive of the electric locomotive. Burning of system components can even lead to machine breakage in severe cases.

Therefore, there is an urgent need for an auxiliary converter device with a voltage type grounding detection technology, which can accurately and quickly determine the ground fault for processing, thereby ensuring the safety and reliability of the electric locomotive operation.

Summary of the invention

The invention provides an auxiliary current changing device, which can accurately and quickly judge the ground fault for processing, thereby ensuring the safety and reliability of the electric locomotive operation.

The present invention is to provide an auxiliary current converting device comprising an auxiliary converter unit connected between a three-phase AC power source and a ground, the auxiliary converter unit being connected with an auxiliary control unit; the auxiliary converter unit comprising a plurality of Auxiliary converters connected in parallel with each other;

Each auxiliary converter is configured to perform an alternating current voltage outputted by the three-phase alternating current power source Step-down processing; and in the event of a ground fault, protect the circuit components; detect the value of the ground current flowing, and send the detected ground current value to the auxiliary control unit;

The auxiliary control unit is configured to receive a ground current value sent by each auxiliary converter, and analyze the ground current value according to a preset standard threshold to determine an auxiliary converter that detects the ground current value. Whether a ground fault has occurred.

The auxiliary converter device as described above, the auxiliary converter specifically includes:

a transformer connected to the three-phase AC power source for performing a step-down process on an AC voltage output by the three-phase AC power source;

a grounding resistance unit connected to the output end of the transformer for protecting the circuit component when a ground fault occurs;

a current sensor having one end connected to the grounding resistance unit and the other end connected to the ground for detecting a ground current value flowing through the grounding resistance unit when a ground fault occurs, and transmitting the detected ground current value to the auxiliary control unit .

The auxiliary current conversion device, as described above, the auxiliary control unit analyzes the ground current value according to a preset standard threshold, which specifically includes:

And comparing and comparing the ground current value with a preset standard ground current threshold to determine whether the auxiliary current transformer that detects the ground current value has a ground fault; or

Obtaining a grounding resistance value of the grounding resistance unit, and obtaining a grounding voltage value according to the grounding current value and the grounding resistance value, and comparing and comparing the grounding voltage value with a preset standard grounding voltage threshold to determine the detection. Whether the auxiliary converter to the ground voltage value has a ground fault.

The auxiliary converter device as described above further includes:

a power unit connected to the vehicle dynamic control system for inverting direct current through the vehicle dynamic control system to alternating current;

The filtering unit has one end connected to the output end of the power unit and the other end connected to the transformer.

In the auxiliary converter device as described above, the power unit is a bridge circuit structure composed of three IGBT modules.

In the auxiliary converter device as described above, the filtering unit includes a filter reactor connected between the power unit and the transformer, and is connected to the filter reactor, and A filter capacitor module in which the transformers are connected in parallel.

The auxiliary converter device as described above, the filter reactor includes a first reactor, a second reactor, and a third reactor respectively connected to the three IGBT modules.

In the auxiliary converter device as described above, the filter capacitor module is a bridge circuit structure composed of three capacitors.

In the auxiliary converter device as described above, the preset standard ground voltage threshold is less than or equal to 36V.

The auxiliary current converting device as described above, wherein the grounding resistance unit is constituted by a first resistor connected to the transformer and a second resistor connected in series with the first resistor, the second resistor and the current sensor Connected.

The auxiliary current conversion device provided by the present invention detects the ground current value flowing through the auxiliary current conversion device and sends it to the auxiliary control unit for analysis processing; when the analysis result exceeds a preset threshold, the auxiliary current converter is determined. When a ground fault occurs, the operation of the circuit can be stopped and processed, and the ground fault can be accurately and quickly judged for processing, and the safety and reliability of the electric locomotive operation can be effectively ensured, which is beneficial to the promotion and application of the market. .

DRAWINGS

1 is a schematic structural diagram of an auxiliary converter device according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of the principle of an auxiliary converter device according to an embodiment of the present invention.

In the picture:

1. Auxiliary converter unit; 2. Auxiliary converter;

3, transformer; 4, grounding resistance unit;

41, a first resistor; 42, a second resistor;

5, current sensor; 6, auxiliary control unit;

7. Vehicle dynamic control system; 8. Power unit;

81, IGBT module; 9, filter reactor;

91, a first reactor; 92, a second reactor;

93, the third reactor; 10, filter capacitor module.

detailed description

The specific embodiments of the present invention are further described in detail below with reference to the drawings and embodiments. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

1 is a schematic structural diagram of an auxiliary converter device according to an embodiment of the present invention; FIG. 2 is a schematic diagram of a schematic diagram of an auxiliary converter device according to an embodiment of the present invention, and the present invention provides a schematic diagram of the present invention. An auxiliary current conversion device comprising: 1, 1 connected between a three-phase AC power source and the earth is connected with an auxiliary control unit 6; 1 comprises a plurality of auxiliary converters 2 connected in parallel with each other,

Each auxiliary converter 2 is configured to perform a step-down process on the alternating current voltage outputted by the three-phase alternating current power source; and protect the circuit components when a ground fault occurs; detect the ground current value flowing through, and detect the detected The ground current value is sent to the auxiliary control unit 6;

The auxiliary control unit 6 is configured to receive a ground current value sent by each auxiliary converter 2, and analyze the ground current value according to a preset standard threshold to determine whether the auxiliary current converter that detects the ground current value occurs Ground Fault.

The specific structure of the auxiliary converter 2 and the auxiliary control unit 6 is not limited, and those skilled in the art can arbitrarily set according to the functions implemented by the same, such as setting the auxiliary converter 2 to include a buck and a protection resistor. And the current detecting device and the like, or may be configured as other structures, etc.; and for the auxiliary control unit 6, it may be set as a processor or a processing circuit, etc.; as long as the above functions can be implemented, no further description is provided herein. In addition, the method for analyzing the ground current value of the auxiliary control unit 6 is not limited, and those skilled in the art can set according to specific design requirements, such as setting the analysis method to directly analyze and judge according to the ground current value, such as The ground current value is compared with a preset standard current threshold; or the ground current value can be processed to analyze and compare the processed values, such as current rate, voltage value, etc., as long as it can be detected If the auxiliary current converter 2 of the ground current value has a ground fault, it is not here. Repeat.

In addition, the three-phase AC power supply is not limited, and a common 380V three-phase AC power supply may be selected for power supply; in addition, the number of the specific auxiliary converters 2 included in 1 is not limited, and those skilled in the art It can be set according to specific application requirements, such as setting the number of auxiliary converters 2 to 3, 4, 5, etc., among them, more commonly, 1 can be set as four auxiliary in parallel with each other. The converter 2 is constructed and the four auxiliary converters 2 are evenly distributed in the circuit, so that the working state of the circuit is effectively detected and monitored.

On the basis of the above-mentioned embodiments, with reference to FIG. 1-2, the specific internal structure of the auxiliary converter 2 is not limited in the technical solution, and it is preferable that each auxiliary converter 2 is Set to include:

The transformer 3 is connected to the three-phase AC power source for performing a step-down process on the AC voltage outputted by the three-phase AC power source;

The grounding resistance unit 4 is connected to the output end of the transformer 3 for protecting the circuit component when a ground fault occurs;

The current sensor 5 has one end connected to the grounding resistance unit 4 and the other end connected to the ground for detecting a ground current value flowing through the grounding resistance unit 4 when a ground fault occurs, and transmitting the detected ground current value to the auxiliary control Unit 6.

The specific type and type of the transformer 3 are not limited, and those skilled in the art may select different types of transformers 3 according to a specific circuit design, and the extent and scope of the step-down processing by the transformer 3 are not limited, and the field The technician can set according to the normal working voltage required by the actual circuit. In order to ensure that the components in the circuit are in a normal working state, it is preferable to set the voltage processed by the transformer 3 to be less than or equal to 36V. Within this range, it is possible to effectively ensure that the devices in the circuit can work normally. Therefore, the above-mentioned voltage range for making the circuit device work normally can also be used as a preset standard ground voltage threshold range, if the operating voltage in the circuit Exceeding this standard ground voltage threshold range can indicate that the circuit is in an abnormal working state, and needs to be checked and processed in time to effectively ensure the stable reliability of the normal operation of the circuit.

In addition, for the specific internal structure of the grounding resistance unit 4 and its specific resistance value, those skilled in the art can use the grounding resistance unit 4 with different structures and different resistance values according to different circuits, for example, the grounding resistance unit 4 can be set. To include several resistors in series The structure may be configured as a structure in which a plurality of resistors are connected in parallel, or a bridge structure composed of a plurality of resistors, etc., wherein the degree of protection of the circuit components by the grounding resistor unit 4 is preferred. The grounding resistor unit 4 is configured to be composed of a first resistor 41 connected to the transformer 3 and a second resistor 42 connected in series with the first resistor 41. The second resistor 42 is connected to the current sensor 5 and is connected in series. The structure can make the current sensor 5 more accurately detect the ground current value flowing through the grounding resistance unit 4, which is more favorable for analyzing and judging the ground fault more accurately.

On the basis of the above-mentioned embodiments, with reference to FIG. 1-2, the analysis method of the auxiliary control unit 6 is not limited in the technical solution. Among them, it is preferable that the auxiliary control unit 6 is based on a preset standard threshold. The ground current value is analyzed and set to specifically include:

Comparing and comparing the ground current value with a preset standard ground current threshold to determine whether the auxiliary converter 2 detecting the ground current value has a ground fault; or

Obtain the grounding resistance value of the grounding resistance unit 4, and obtain the grounding voltage value according to the grounding current value and the grounding resistance value, and compare and compare the grounding voltage value with a preset standard grounding voltage threshold value to determine the auxiliary of detecting the grounding voltage value. Whether the converter 2 has a ground fault.

The specific structure of the auxiliary control unit 6 is not limited, for example, the auxiliary control unit 6 may be configured to be constituted by a single central processing unit, or the auxiliary control unit 6 may be configured to be constituted by a plurality of main control circuits, and the like. A person skilled in the art can arbitrarily set the ground current value or the ground voltage value according to the function of the specific implementation, and can determine the specific faulty auxiliary converter 2, This will not be repeated here.

The auxiliary current conversion device provided by the invention detects the ground current value flowing through the grounding resistance according to the current sensor 5, thereby obtaining a potential difference between the connection point between the grounding resistance and the transformer 3 and the earth, and the ground current value and the potential There is a proportional relationship between the differences. When the potential difference is larger, the ground current value is larger. When the potential difference is smaller, the ground current value is smaller. When the ground current value or the ground voltage value is detected to exceed the safe range, it is determined. The auxiliary converter 2 has a ground fault, which can stop the operation of the circuit and process it, so that the ground fault can be accurately and quickly judged for processing, and the safety and reliability of the electric locomotive operation can be effectively ensured. Market promotion and application.

Based on the above embodiments, with reference to FIGS. 1-2, it is clearer for clarity. To solve the specific working process of the auxiliary converter device, the auxiliary converter device is further configured to further include:

The power unit 8 is connected to the vehicle dynamic control system 7 for inverting the direct current through the vehicle dynamic control system 7 into an alternating current;

The filtering unit has one end connected to the output end of the power unit 8 and the other end connected to the transformer 3.

Wherein, for the vehicle dynamic control system 7, the main function realized is to determine the driving state of the vehicle. In general, the vehicle dynamic control system 7 can be set to include a wheel speed sensor disposed on the wheel for tracking each a state of motion of a wheel; a steering wheel angle sensor disposed on the steering wheel of the vehicle for sensing the angle of rotation of the steering wheel; a yaw rate sensor for recording all movement of the vehicle about a vertical axis; and a lateral acceleration sensor for detecting steering The magnitude of the centrifugal force during traveling; the wheel displacement sensor is used to measure the change of the relative position of the wheel and the body; of course, those skilled in the art can also include other devices according to the functions that need to be implemented; and the above for the vehicle dynamic control system 7 The connection manner and the internal structure of the structure are not limited, and those skilled in the art can arbitrarily set according to the functions and specific design requirements of the implementation, and details are not described herein again.

In addition, the specific internal structure of the power unit 8 and the filtering unit is not limited, and those skilled in the art can set according to the functions implemented by the same, for example, the power unit 8 can be set as an inverter or an inverter circuit, and the specific inverse The transformer or the inverter circuit may select a common device in the prior art; and for the filtering unit, the filtering unit may be set as a filter circuit including a capacitance and/or a reactance, etc., as long as the power unit 8 and the filtering unit can be implemented. The above effects are sufficient; among them, in order to match the normal operating voltage in the circuit and to ensure the realization effect of the power unit 8 and the filtering unit, it is preferable to set the power unit 8 as a bridge composed of three IGBT modules 81. Circuit structure; the filtering unit is arranged to include a filter reactor 9 connected between the power unit 8 and the transformer 3, and a filter capacitor module 10 connected to the filter reactor 9 and connected in parallel with the transformer 3.

The IGBT module 81 of the prior art is used for the IGBT module 81 in the power unit 8 described above, and the specific structure of the filter reactor 9 in the power unit 8 is not limited, and those skilled in the art can perform the circuit design according to the design requirements of the circuit. Arbitrarily set, in which the power reactor 8 inverts the direct current into three-phase alternating current, therefore, in order to facilitate the processing of the circuit, the filter reactor 9 is set to include the first reactor 91 connected to the three IGBT modules 81, respectively. , The second reactor 92 and the third reactor 93, wherein the first reactor 91, the second reactor 92 and the third reactor 93 are connected to the three-phase alternating current after the inverter, thereby effectively ensuring the third The phase AC power is filtered to remove the burrs in the electrical signal, so that the obtained ground current value or ground voltage value is more stable and reliable.

In addition, the specific structure of the filter capacitor module 10 in the filtering unit is not limited, and the filter capacitor module 10 may be configured to include a circuit structure in which a plurality of capacitors are connected in series or in parallel, in order to better filter the three-phase alternating current. The filter capacitor module 10 is configured as a bridge circuit structure composed of three capacitors, so that the filter reactor 9 and the filter capacitor module 10 can effectively filter the three-phase alternating current to ensure the input to the transformer 3 The quality of the alternating current signal, in turn, ensures the accuracy and reliability of the ground current or ground voltage.

In the specific application, the technical solution mainly uses the grounding resistance unit 4 and the current sensor 5 to work together, and can timely and accurately detect the grounding current value. When there are multiple auxiliary converters 2, it can accurately distinguish which one. The auxiliary converter 2 is faulty for processing. The auxiliary converter 2 for detecting the ground fault in the present technical solution can adopt two methods, one is to analyze the ground current value flowing through the grounding resistance unit 4. Judgment; the other is to analyze and judge the grounding voltage value of the grounding resistance unit 4, the specific process is as follows:

The operation process of analyzing the ground current value:

The auxiliary converter device is arranged to be connected to the three-phase AC power source by the four auxiliary converters 2, and when one of the auxiliary converters 2 has a ground fault, the grounding resistor unit 4 and the transformer 3 are used as At the potential point N, a potential difference occurs between the corresponding N and the ground, so that a ground current flows through the grounding resistance unit 4, and the ground current flowing through the grounding resistance unit 4 can be detected by the set current sensor 5. The current sensor 5 transmits the detected ground current value to the auxiliary control unit 6, and the auxiliary control unit 6 analyzes the ground current value. When the analysis result is that the ground current value is detected to exceed the preset standard ground current threshold (ie, In the safety range, it is considered that the auxiliary converter 2 corresponding to the ground current value has a ground fault. At this time, the auxiliary converter 2 in the circuit is stopped, and relevant processing is performed to eliminate the ground fault, and the ground fault is to be eliminated. After that, the auxiliary converter 2 can be kept working; when the analysis result is that the detected ground current value does not exceed the preset standard ground current Value, it indicates that the current value corresponding to the ground auxiliary converter 2 to the normal working state.

The operation process of analyzing the ground voltage value:

On the basis of the above operation process, the auxiliary control unit 6 further obtains the resistance value of the grounding resistance unit 4, and then obtains the ground voltage value by the obtained ground current value and the resistance value, and the auxiliary control unit 6 determines the ground voltage value. Compared with the preset standard ground voltage threshold less than or equal to 36V (ie, the safe range), when the analysis result is that the ground voltage value exceeds the preset safety range value, the auxiliary converter 2 corresponding to the ground voltage value is considered A ground fault occurs, at which time the auxiliary converter 2 in the circuit is stopped, and relevant processing is performed to eliminate the ground fault. After the ground fault is removed, the auxiliary converter 2 can continue to operate; when the analysis result is the ground voltage value Within the pre-set safety range value, the auxiliary converter 2 corresponding to the ground voltage value is considered to be in a normal operating state.

In addition, a plurality of potential points may be set in the circuit, and a voltage value between the plurality of potential points may be detected. After analyzing the voltage values between the plurality of potential points, the specific position of the ground fault may be more accurately determined and The degree of ground fault, the specific implementation process will not be described here.

The auxiliary converter device provided by the present invention detects the ground current value flowing through the grounding resistance according to the current sensor 5, thereby obtaining a potential difference between the ground point resistance and the transformer N and the earth, and the ground current value and the potential There is a proportional relationship between the differences. When the potential difference is larger, the ground current value is larger. When the potential difference is smaller, the ground current value is smaller. When the ground current value or the ground voltage value is detected to exceed the safe range, it is determined. The auxiliary converter 2 has a ground fault, which can stop the operation of the circuit and process it, so that the ground fault can be accurately and quickly judged for processing, and the safety and reliability of the electric locomotive operation can be effectively ensured. Market promotion and application.

Finally, it should be noted that the above embodiments are merely illustrative of the technical solutions of the present invention, and are not intended to be limiting; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will understand that The technical solutions described in the foregoing embodiments may be modified, or some or all of the technical features may be equivalently replaced; and the modifications or substitutions do not deviate from the technical solutions of the embodiments of the present invention. range.

Claims

An auxiliary current conversion device, comprising: an auxiliary converter unit connected between a three-phase AC power source and a ground, the auxiliary converter unit being connected with an auxiliary control unit; the auxiliary converter unit comprising a plurality of mutual Parallel auxiliary converters;

Each auxiliary converter is configured to perform a step-down process on the alternating current voltage outputted by the three-phase alternating current power source; and protect the circuit component when a ground fault occurs; detect a ground current value flowing through, and detect the The ground current value is sent to the auxiliary control unit;

The auxiliary control unit is configured to receive a ground current value sent by each auxiliary converter, and analyze the ground current value according to a preset standard threshold to determine an auxiliary converter that detects the ground current value. Whether a ground fault has occurred.
The auxiliary converter according to claim 1, wherein the auxiliary converter specifically comprises:

a transformer connected to the three-phase AC power source for performing a step-down process on an AC voltage output by the three-phase AC power source;

a grounding resistance unit connected to the output end of the transformer for protecting the circuit component when a ground fault occurs;

a current sensor having one end connected to the grounding resistance unit and the other end connected to the ground for detecting a ground current value flowing through the grounding resistance unit when a ground fault occurs, and transmitting the detected ground current value to the auxiliary control unit .
The auxiliary converter device according to claim 2, wherein the auxiliary control unit analyzes the ground current value according to a preset standard threshold, which specifically includes:

And comparing and comparing the ground current value with a preset standard ground current threshold to determine whether the auxiliary current transformer that detects the ground current value has a ground fault; or

Obtaining a grounding resistance value of the grounding resistance unit, and obtaining a grounding voltage value according to the grounding current value and the grounding resistance value, and comparing and comparing the grounding voltage value with a preset standard grounding voltage threshold to determine the detection. Whether the auxiliary converter to the ground voltage value has a ground fault.
The auxiliary converter device according to claim 2, further comprising:

Power unit, connected to the vehicle dynamic control system, for dynamic control through the vehicle The DC power of the system is reversed to AC;

The filtering unit has one end connected to the output end of the power unit and the other end connected to the transformer.
The auxiliary converter device according to claim 4, wherein the power unit is a bridge circuit structure composed of three IGBT modules.
The auxiliary converter device according to claim 4, wherein the filtering unit comprises a filter reactor connected between the power unit and the transformer, and is connected to the filter reactor, and A filter capacitor module in which the transformers are connected in parallel.
The auxiliary converter device according to claim 5, wherein the filter reactor comprises a first reactor, a second reactor, and a third reactor respectively connected to the three IGBT modules.
The auxiliary converter device according to claim 6, wherein the filter capacitor module is a bridge circuit structure composed of three capacitors.
The auxiliary converter device of claim 3, wherein the predetermined standard ground voltage threshold is less than or equal to 36V.
The auxiliary current transformer according to any one of claims 2-8, wherein the grounding resistance unit is composed of a first resistor connected to the transformer and a second in series with the first resistor A resistor is formed, and the second resistor is connected to the current sensor.