Power circuit, and computer-readable recording medium storing a control program for power circuits

• Main Authors: HIRAOKA NOBUYASU, DOI HIROTAKA, SHIMATANI KEISUKE, SARUWATARI HIROTAKA, NAKASHITA YUUKO, YAGI SATOSHI
• Format: Patent
• Language: English
• Published: 24.03.2015
• Subjects: CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORSOR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS; GENERATION

When an abnormality occurs in a refrigeration cycle, the inverter motor provided in the air conditioner is stopped reliably and contacts of the main relay are prevented from degradation and fusion. A power circuit 1 of the air conditioner includes a rectifier circuit RC, a capacitor C (smoothing unit), a main relay 10 provided on a current path between the rectifier circuit RC and the capacitor C, an inverter circuit 30, a microcomputer 100, and a delay circuit 40. The microcomputer 100 has an inverter circuit control unit 110, a main relay opening/closing control unit 120, a waveform forced cut-off unit 130, and a cut-off signal output unit 140. Where a high-pressure switch 200 (abnormality detection unit) detects a high-pressure abnormality and outputs a high-pressure abnormality signal to the waveform forced cut-off unit 130 when the main relay 10 is in a closed state, the waveform forced cut-off unit 130 electrically cuts off the inverter circuit control unit 110, and the cut-off signal output unit 140 outputs a cut-off signal, which sets the main relay 10 to the open state, to the main relay 10 via the delay circuit 40.