Patent ID: 9667131
Date: 2017-05-30
CPC Classifications: H02H,H02M

Claim:
1. A differential protection method for bridge circuit in current converter control system, being characterized in that, the differential protection method includes the steps of: 1). obtaining sample values of the three-phase current for the current converter control system at AC side thereof, and calculating the absolute value of each sampling value respectively; 2). calculating the value of current at the AC side of the current converter control system by the step of: the value of current at the AC side being k1 times of the sum of three absolute values of sample values; and 3). determining whether to perform a relay protection for the current converter control system according to the value current at the AC side of the current converter control system by the step of: If |Id−iv|>k2, performing a relay protection; wherein, k1 is a value between 0 to 1, Id is an actual measured value of direct current side of the current converter control system, iv is a current value of AC side, and k2 is a set value greater than 0.