| 摘要 |
PURPOSE:To lengthen the operating time of a compressor motor by using the specified frequency of a V/F pattern as temporary maximum frequency for a fixed time and controlling the operation of an inverter when the state of overload is detected on starting. CONSTITUTION:When the detecting voltage of an indoor temperature is higher than reference voltage, an output from a comparator 15 reaches 'L'. A microcomputer 9 decides the state of load to be the state of overload when a signal from a detector 10 reaches 'L', regulates frequency, using frequency F1 as maximum frequency for the time t1 and employing frequency F2 as maximum frequency for the time t2, and elevates output frequency to maximum frequency Fmax after the time t2 passes. When no overload state is decided, output frequency is increased up to maximum frequency Fmax immediately after a compressor motor 6 is started. Even when the compressor motor 6 is operated at maximum frequency Fmax and output frequency lowers up to prescribed frequency or less and output frequency is elevated again, frequency is controlled similarly. |
