JPS61169628A - Compressor driver - Google Patents

Abstract

PURPOSE:To enable free setting of the rotation of compressor thus to follow efficiently to load variation by providing an induction motor for driving a compressor and a frequency converter for converting the input frequency to random frequency and outputting. CONSTITUTION:A compressor 2 will feed pressurized air to a combuster 3. Here, an induction motor 1 for driving the compressor 2 and a frequency converter 6 for converting the input frequency into random frequency and outputting are provided. Then the output frequency of the frequency converter 6 fed through commercial power source is gradually increased to perform fuel supply to the combuster 3 and ignition at the time point when the rotation of compressor 2 has reached to such time point as to produce proper pressure thus to enter into self-operation thereafter the frequency to be fed to the induction motor 1 is controlled to optimize the air/fuel ratio. Since the rotation of compressor 2 can be set freely with high accuracy through simple structure, it can follow well to considerable load variation with high efficiency.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a compressor drive device used to drive a compressor that supplies pressurized gas to a gas turbine or the like.

[Conventional technology]

Generally, a compressor-driven gas turbine supplies pressurized air to a combustor by a compressor, is driven by hot gases generated from the combustor, and its output is transmitted to a driven machine via a power turbine. To start these power systems, a starter, such as an electric motor or steam turbine, starts the compressor, and once the compressor has reached a sufficient rotational speed to produce the appropriate pressure, it supplies fuel to the combustor and ignites it. When starting is completed, the starter is placed in an idling state or is disconnected from the line using a detachable joint. After that, part of the power from the compressor drive gas and turbine is used to drive the compressor, and high-temperature gas is continuously obtained from the combustor.

[Problem that the invention seeks to solve]

However, the rotational speed of the compressor-driven gas turbine must be controlled in conjunction with the output turbine to maintain the rotational speed according to the purpose of the driven machine, so changes in the load or the calorific value of the fuel must be controlled. There is a drawback in that it is not possible to control the number of revolutions for optimum air amount control corresponding to the fuel amount adjustment accompanying this. In order to eliminate this drawback, the air volume is controlled by adjusting the stator vane angle of the compressor and by oil bypass, but the structure is complicated and
Because the control width was narrow, the effect of optimal air amount control was insufficient.

[Means for solving problems]

In order to solve these problems, the present invention provides a drive device that includes a continuous rated induction motor and a frequency converter that supplies power at an arbitrary frequency to the induction motor.

[Effect]

At startup, the frequency of the continuously variable frequency converter is increased to increase the rotation speed of the compressor, and when the appropriate pressure is reached, fuel is supplied to the combustor and ignited, and from then on, the air-fuel ratio is optimized. Frequency control is performed using the chemical instrumentation signal, and the rotation speed of the compressor is controlled.

〔Example〕

FIG. 1 is a block diagram showing one embodiment of the present invention.

In the figure, 1 is a continuous rated induction motor, 2 is a compressor, 3 is a combustor, 4 is a compressor-driving gas turbine, 5 is a driven machine, and 6 is an output frequency that is arbitrarily controlled in the range of about 0 to 200 Hz. It is a frequency converter that can be used.

The operation of the device configured as described above is as follows. Gradually increases the output frequency of the frequency converter 6 to which commercial power is supplied, and when the rotation speed of the compressor 2 reaches an appropriate pressure, fuel is supplied and ignited to the combustor 3, and self-blade operation begins. Thereafter, the frequency supplied to the induction machine 1 is controlled so that the air-fuel ratio is optimized.

By increasing the frequency of the induction motor, for example, in the case of a two-pole machine with a power source frequency of 150 Hz, the rotation speed is 9000 revolutions per minute, and it is possible to reduce the physical size of the motor. If a two-pole machine is driven at a commercial frequency, it is not possible to obtain such a rotation speed, but if commercial power is supplied via the frequency converter 6 as in the present invention, the rotation speed of the compressor 2 can be adjusted to the turbine-driven speed. The value is the same as in the case of . In addition, in this invention, the rotation speed of the compressor is determined independently of the rotation speed of the turbine, so high efficiency design can be freely performed without restrictions related to the output turbine.
Become.

FIG. 2 shows a case where the driven machine 5 is constituted by a generator; in this case, in addition to supplying the generated power to the power system 7,
A part of the generated power is consumed by the induction motor IK via the frequency converter 6 for driving the compressor.

In the future, gas turbine compressors will not only have the function of simply supplying combustion air to the combustor, but will also be required to have a suction function for various flammable gases. You can also choose freely.
It is also extremely easy to meet such requests. In addition to responding to gas turbine load fluctuations through fuel control in the combustor, it is effective to improve the turbine speed fluctuation characteristics in response to load fluctuations by linking compressor rotation speed control. In particular, when the driven machine 5 is a generator, it is extremely effective to perform fuel control and suppress the compressor rotation speed in order to suppress overspeed due to full load interruption.

〔Effect of the invention〕

As explained above, in this invention, the compressor is driven by an induction motor, and the induction motor is driven by a frequency converter whose output frequency can be set arbitrarily, which simplifies the configuration and improves reliability. At the same time, since the rotation speed of the compressor can be freely set by changing the output frequency of the frequency converter, it is possible to efficiently follow large load fluctuations.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the invention, and FIG. 2 is a block diagram showing another embodiment. 1...Induction motor, 2...Compressor, 3...
Φ...Combustor, 4...Turbine, 5...Driven machine, 6...Frequency converter.

Claims (1)

[Claims] A compressor drive device that drives a compressor that supplies pressurized air to a combustor, characterized by comprising an induction motor that drives the compressor and a frequency converter that converts an input frequency to an arbitrary frequency and outputs the frequency. Compressor drive device.