ACTIVE FILTER

• Main Author: KIDOGUCHI HIDETAKA
• Format: Patent
• Language: English
• Published: 21.10.1994
• Edition: 5
• Subjects: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC,OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWERSUPPLY SYSTEMS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTINGELECTRIC POWER; CONTROL OR REGULATION THEREOF; CONTROLLING; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUTPOWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION; PHYSICS; REGULATING; SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES; SYSTEMS FOR STORING ELECTRIC ENERGY

PURPOSE:To make it possible to compensate higher harmonics which does not cause divergence phenomenon by performing a control by means of determining a reactive current component contained in the actual value of a compensating current and subtracting it from a command value for a control group which determines higher harmonic component from a detected value of a power supply current and performs the control using the component as the compensating current. CONSTITUTION:An active filter determines a reactive component from a detected value IC of a compensating current obtainable through a compensating current detector 4 in a reactive component compensating circuit 130 and subtracts a reverse-phased reactive current command IQ' from a compensating current command value IC* in an adder-subtractor 131 in such a manner that said reactive component becomes zero. In consequence, compensation for stable higher harmonics having no divergence of reactive current becomes possible.