POWER CONVERTER

• Main Author: NAGANUMA KATSUNORI
• Format: Patent
• Language: English
• Published: 22.11.1996
• 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 RELATED TOTRANSPORTATION; 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; ELECTRIC EQUIPMENT OR PROPULSION OF ELECTRICALLY-PROPELLEDVEHICLES; ELECTRICITY; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES, IN GENERAL; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERATION; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; PERFORMING OPERATIONS; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE; TRANSPORTING; VEHICLES IN GENERAL

PURPOSE: To reduce in size a power converter by reducing the capacity of a filter capacitor in a main converter using an IGBT. CONSTITUTION: When a short-circuit damage occurs in the IGBT 11a of either a two-phase bridge circuit 10 or a three-phase bridge circuit 30, the damage is detected by a current detector 22a, the thyristor 28 of a quick discharging circuit is fired, and a vacuum breaker 2 is operated. Then, a power converter is stopped before a filter capacitor 21b is charged by a shorter quick discharging circuit having a time constant shorter than the discharging circuit without resistor 25. Accordingly, even if the short-circuit damage occurs in the either of the IGBTs and either upper or lower filter capacitor 21a is short-circuited, the other filter capacitor 21b can be so protected as not to be raised to the DC link voltage, and hence the capacitors 21a, 21b can be used in such a manner that they can use a capacitor of low withstand voltage of about 1/2 of the DC link voltage.