| 摘要 |
PURPOSE:To prevent an electric compressor from breakdown due to false connection by switching two phases of an inverter controller from each other to make the electric compressor rotate forward when detecting a reverse rotation of said compressor. CONSTITUTION:An AC input current (i) is detected by a current transformer 34 and inputted to an A/D conversion input of a microcomputer 23 via a rectifier 33. If the AC input current (i) exceeds a certain value between 30 Hz and 50 Hz operating frequencies. The fact is detected that the rotation of a compressor 1 is in reverse. In this manner, outputs OUT1 and OUT3, and OUT2 and OUT4 of the microcomputer 23 are respectively switched from each other and then outputted, and the compressor 1 is rotated in a normal direction so as to be capable of making a normal cooling or heating operation. |
