Bypass modules for high-voltage frequency converter power units

Abstract

The invention discloses a bypass module for a high-voltage frequency converter power unit, which includes a bypass drive circuit for driving a bypass contactor switch of the power unit, and the bypass module also includes a bypass state detection circuit, a bypass The failure feedback circuit and the communication failure feedback circuit, the bypass state detection circuit is used to detect whether the bypass contactor is driven successfully, and the bypass failure feedback circuit is used to feed back the bypass failure signal detected by the bypass state detection circuit to the high-voltage inverter The main control system of the inverter, the communication fault feedback circuit is used to timely feed back the signal of the bypass optical fiber communication fault to the main control system of the frequency converter. Utilize the triode in the bypass drive circuit to work in the saturation region, the collector and the emitter are turned on, the relay is energized and closed, and the bypass signal is displayed in time through the first signal circuit, so that the bypass drive circuit has a simple structure , low cost and high reliability advantages.

Description

technical field [0001] The invention relates to the technical field of frequency converters, in particular to a bypass module used for a power unit of a high-voltage frequency converter. Background technique [0002] With the development of power electronics technology, the application of high-voltage frequency converters composed of power unit cascade technology is becoming more and more extensive. In the application of cascaded high-voltage inverters, since high-voltage motors are generally used in more critical occasions, the failure of high-voltage inverters will seriously affect the normal production of the enterprise, and even cause major economic losses. For this reason, the power unit bypass device is usually used to improve the stability and reliability of the high-voltage inverter. When a part of the high-voltage inverter fails, it can ensure uninterrupted operation and avoid the shutdown of the high-voltage inverter. [0003] In cascaded high-voltage inverters, e...

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Problems solved by technology

[0004] The bypass module of the cascaded frequency converter in the prior art has several disadvantages during use: 1) the design is complicated, the cost is high and the volume is large; 2) the state of the bypass contactor cannot be automatically fed back; 3) it cannot be automatically Feedback whether the operation of the bypass contactor is successful; 4) Can not automatically feedback the failure of the optical fiber communication between the main control system of the inverter and the bypass module; resulting in low efficiency of the bypass device of the power unit, reducing the stability and reliability of the inverter

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