Converter control method and controlling device

Abstract

The invention discloses a converter control method and a controlling device. The converter comprises two converting units having the same topology structures. The direct current sides of the two converting units are connected to the direct current source in parallel, and the AC sides of the two converting units are connected to an alternating current filter in parallel, and the midpoints of the direct current bus of the two converting units are directly connected. The converter also comprises an inductor which is in series connection between the midpoint of at least one converting unit and thealternating current filter. The converter control method comprises the steps that the internal temperature value of the converter can be obtained; whether the internal temperature value of the converter is lower than the first set value can be determined; if the internal temperature value of the converter is lower than the first set value, the on-off state of switch tubes in the two converting units can be controlled. Current can flow out from the anode of the direct current source, and passes through a plurality of switch tubes and inductors in the converter and returns to the cathode. The current value is no more than the limit value, and thereby the power semiconductor device of the converter can be prevented from being failed and damaged due to the fact that the voltage stress is excessively large when the converter is started at low temperature.

Description

technical field [0001] The present invention relates to the technical field of power electronics, and more specifically, relates to a control method and a control device for a converter. Background technique [0002] Power semiconductor devices such as IGBT (Insulated Gate Bipolar Transistor, Insulated Gate Bipolar Transistor) or MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor, Metal-Oxide-Semiconductor Field-Effect Transistor) commonly used in converters are used under other conditions In this case, the lower the temperature, the greater the voltage stress. Therefore, when the converter is started under low temperature conditions, the power semiconductor devices of the converter may fail and be damaged due to excessive voltage stress. Contents of the invention [0003] In view of this, the present invention provides a converter control method and a control device to avoid failure and damage of the power semiconductor device of the converter due to excessive vol...

AI Technical Summary

Problems solved by technology

Therefore, when the converter is started under low temperature conditions, the power semiconductor devices of the converter have the risk of failure and damage due to excessive voltage stress

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