A control method and device for a three-phase three-wire rectifier circuit

Abstract

The invention discloses a control method and equipment of a three-phase three-wire rectifying circuit. The method is characterized in that when input voltage is not smaller than rated input voltage and not larger than a set input voltage upper limit, soft starting of bus voltage is achieved by following manners, to be more specific, a first-phase positive thyristor and a second-phase negative thyristor are controlled to be connected when the wire voltage angle between the second phase and the first phase is the first set angle to allow the amplitude of obtained semi-bus voltage to be smaller than the peak of the input voltage after the soft starting of the bus voltage, the first phase and the second phase are two optional phases of a phase A, a phase B and a phase C, and the problem of excessively high bus voltage is avoided; after the soft starting of the bus voltage, if the input voltage is still not smaller than the rated input voltage, each phase of thyristor is controlled to be incompletely connected, and accordingly the risk that the bus voltage is high and uncontrollable after high voltage is input for rectifying.

Description

technical field [0001] The invention relates to the technical field of circuit control, in particular to a control method and equipment for a three-phase three-wire rectifier circuit. Background technique [0002] Compared with the I-type three-level rectifier, the Vienna-like rectifier has the characteristics of fewer switching devices and lower cost, so it is widely used in high-voltage and high-power applications. [0003] Specifically, such as figure 1 As shown in FIG. 1 , it is a schematic diagram of a circuit topology structure of a common Vienna rectifier. Among them, Ua, Ub, and Uc are input phase voltages, Lga, Lgb, and Lgc are input side filter inductors, Ca, Cb, and Cc are input side filter capacitors, L1~L6 are boost inductors, C1, C2 are bus capacitors, D1 ~D6 is the input rectifier thyristor, D7~D12 is the BOOST (boost) circuit freewheeling diode, Q1~Q6 is the BOOST circuit switch tube, Udc+ is the positive bus voltage, Udc- is the negative bus voltage, N1 is...

AI Technical Summary

Problems solved by technology

[0007] The embodiment of the present invention provides a control method and equipment for a three-phase three-wire rectifier circuit, which is used to solve the problem that the half-bus voltage amplitude obtained before the BOOST circuit is not working after the thyristor is completely turned on in the current Vienna-like rectifier may be too high and Problems such as high and uncontrollable bus voltage after input high-voltage rectification

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