Causes and Solutions of Overvoltage of Inverter(II)

To deal with the overvoltage fault, the key is how to deal with the excess energy in the intermediate DC loop in time, and how to avoid or reduce the excess energy feeding to the intermediate DC circuit, so that the degree of overvoltage is limited to the allowable limit.

1. In the case of an impulse overvoltage on the input side of the power supply, an overvoltage caused by lightning, a voltage formed when the compensating capacitor is on or off, It can be solved by parallel surge absorber on input side or series reactor.

2. The method of adding appropriate capacitor to the intermediate DC circuit plays an important role in stabilizing the voltage and improving the ability of the circuit to withstand overvoltage. It is an effective way to solve the overvoltage of frequency converter by increasing the capacitance of the circuit properly or replacing the capacitor with long running time and decreasing capacity in time. This also includes in the design phase of the choice of a large capacity of the inverter, is to increase the capacity of the inverter in exchange for the improvement of overvoltage capacity.