Improvement and implementation of sync-capture algorithm
Han Ji · Dianli zidonghua shebei · 2013
Two common sync-capture algorithms are analyzed. Algorithm 1 predicts the closing time according to the relationship among phase angle difference,slip frequency and slip frequency acceleration,while algorithm 2 applies the contemporary forecast theory to predict the closing time based on the phase angle difference order. Both are improved. For algorithm 1,the phase angle difference between short time interval is estimated with interpolation principle and the closing command is issued if the closing condition is satisfied,otherwise continue the algorithm. For algorithm 2,the parabolic curve fitting prediction algorithm combined with the residual analysis is added,which is more accurate than linear fitting,and the measuring system of phase angle difference,which has direct influence on algorithm,is improved by acquiring the original data at the zero-crossing-point of square wave and by increasing the data density through data interpolation.Experimental results prove that the improved algorithms enhance obviously the quality of synchronous closing.