A power module redundant energy acquisition circuit and control method

Abstract

The invention discloses a power module redundant energy harvesting circuit, the power module includes at least one power semiconductor device, a first capacitor C1, and a first bypass switch K1; the redundant energy harvesting circuit of the present invention includes a first regulator tube VD1, a second Two regulator tubes VD2, the second switch K2, the first resistor R1, the second resistor R2, the second capacitor C2, the power board and the control board; the power board obtains energy from the capacitor C1 and supplies it to the control board The power supply charges the capacitor C2; the control board controls the closing of the bypass switch K1 by triggering the switch K2. The solution of the present invention uses the breakdown characteristics of the first voltage regulator tube to charge the capacitor C2 when the power supply board fails, and uses the breakdown characteristics of the second voltage regulator tube to provide a trigger command for the switch K2, so as to realize bypass in the case of a power supply board failure. The reliable bypass of the circuit switch avoids the equipment shutdown under the fault condition of the power module power board, and the solution cost is low and the reliability is high.

Description

technical field [0001] The invention belongs to the field of power electronics, in particular to a power module redundant energy-taking circuit and a control method. Background technique [0002] Voltage source converter technology is a new type of commutation technology based on turn-off device IGBT (insulated gate bipolar transistor) and pulse width modulation (PWM) technology. In low-voltage applications, two-level converters composed of IGBTs have been widely used. In order to solve the high-frequency jumps in the output voltage of the converters, the resulting dv / dt stress of equipment, large system losses, high noise and To solve the harsh electromagnetic environment and other problems, the three-level voltage source converter was proposed, which expanded the application occasions of the voltage source converter in terms of voltage level and capacity. [0003] With the emergence of Modular Multilevel Converter (MMC), multilevel converters have also been successfully a...

AI Technical Summary

Problems solved by technology

The essence of the circuit is that the bypass switch capacitor Cc is connected in parallel with the sub-module capacitor Csm after the resistor R1 is connected in series, and the capacitance value of the bypass switch capacitor is generally hundreds of microfarads, and the submodule capacitor Csm is generally several millifarads to more than ten millifarads, so it is difficult to Ensure that the capacitor of the bypass switch is charged to the rated value and the capacitor of the sub-module is not overvoltage; furthermore, if the power supply of the sub-module fails, the control board of the sub-module will not work, and the command to close the bypass switch cannot be provided; In this case, if the normally closed point K2 is used to connect the bypass switch capacitor and the contact control coil circuit in series, the bypass switch capacitor will be short-circuited and cannot be charged.

Therefore, with this scheme, there is a risk of overvoltage damage to the sub-module capacitor and failure of the bypass switch to close when the sub-module energy-taking power supply fails.

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