A self-adjusting voltage filtering technique compensating for dynamic errors of capacitive voltage transformers

摘要

#$%^&*AU2008201130B220111103.pdf#####A SELF-ADJUSTING VOLTAGE FILTERING TECHNIQUE COMPENSATING FOR DYNAMIC ERRORS OF CAPACITIVE VOLTAGE TRANSFORMERS ABSTRACT A method of digitally correcting the raw output voltage (605) from a Capacitive Voltage Transformer (CVT) with the intent to remove transient components impacting on transient accuracy of protection function. A typical CVT is represented using three parameters in the linear CVT model. A digital filter (608) designed based on the three parameters and incorporating a dedicated mechanism to ensure numerical stability of the former. A method of self-adjusting the said filter based on system events and performed after the method has been deployed in the field and supplied from a specific CVT.6/12 FIG. 6 605 620 606 608 + V VAIN CVT Filter I' VA-CVT __j 615 Numerical VA PI Stability Loop 604 610