PARALLEL OPERATION CONTROL DEVICE FOR CONSTANT VOLTAGE CONSTANT FREQUENCY POWER SOURCE DEVICE

摘要

PURPOSE:To effect parallel operation stably, by a method wherein a system, effecting phase control based on an effective power difference between CVCFs(constant voltage constant frequency power source devices), is provided with a correction by using wattless power difference between both of the CVCFs upon the parallel operation of the CVCFs. CONSTITUTION:A CVCF parallel operation control device impresses and inputs an ineffectual power difference from subtractors 114, 214 into PLLs 119, 219 through switches 116, 216. An offering correction signal with respect to an effective power difference is generated in a controller 15 by the ineffectual power difference while the offering correction signal is added to the effective power difference by an adder 16. The correction signal is inputted into an effective power difference controller 10 and generates an offering input from a phase comparator 9 into a phase difference signal. According to this method, the control phase of the CVCF, into which an effective power flows, is advanced while the control phase of another CVCF, from which the effective power is forced out, is delayed whereby the control may be converged when the effective power is conducted from one CVCF system into the other CVCF system and a DC voltage is increased during the parallel operation of inverters 104, 204 under a light load.