MOMENTARY DROP COMPENSATOR

• Main Authors: OI KAZUNOBU, MUNESHIMA MASAKAZU
• Format: Patent
• Language: English
• Published: 05.11.2009
• 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; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUTPOWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION; SYSTEMS FOR STORING ELECTRIC ENERGY

PROBLEM TO BE SOLVED: To prevent the interference between voltage compensating control by a series inverter and control that zeroes switch current by a parallel inverter, in an instantaneous compensator where the series inverter is combined with the parallel inverter. SOLUTION: When the compensator detects momentary drop, it outputs a current control command S2 that operates the parallel inverter as a voltage command Vrefp and zeroes the current flowing to a switch, by supplying a rated current from the parallel inverter to a load and also outputs a voltage control command S4 for operating the series inverter as a voltage command Vrefs, thereby supplying a compensating voltage from the series inverter to the load. At this time, the compensator prevents the interference between the voltage compensating control by the series inverter and the control for zeroing the switch current by the parallel inverter, by gradually reducing the value of the voltage control command S4 thereby lowering the voltage value of the series inverter, whereby overshooting of load voltage is suppressed. COPYRIGHT: (C)2010,JPO&INPIT