MOTOR CONTROL EQUIPMENT

• Main Authors: NOTOHARA YASUO, TAWARA KAZUO, FUTAMI MOTOO
• Format: Patent
• Language: English
• Published: 02.05.1995
• Edition: 6
• 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; CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION ORPROCESSING OF GOODS; CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORSOR DYNAMO-ELECTRIC CONVERTERS; CONTROL OR REGULATION THEREOF; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUTPOWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERATION; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE

PURPOSE:To prevent the increase in D.C. voltage in an operating motor by controlling the switching operation of a power-factor improvement circuit through a switching operation control means. CONSTITUTION:An A.C. power supply 1 is connected to a full-wave rectification circuit 2, which outputs pulsating direct current. A reactor 3, a diode 4 and a transistor 5 constitute a boosting chopper circuit. The boosting chopper circuit is connected to the output side of the full-wave rectification circuit 2, and boosts pulsating D.C. voltage by means of the switching operation of the transistor 5 and the energy storing effect of the reactor 3. The boosted pulsating D.C. voltage is fed to a smoothing capacitor 6, which then outputs stable D.C. voltage. A converter control means 13 improves the power factor of the power supply 1 suing the full-wave rectification circuit 2 and the boosting chopper, and further controls D.C. voltage based upon a direct current command and a converter stop signal. This prevents the incease in D.C. voltage and the degradation power factor.