| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To control an electric current phase and a rotational frequency of a compressor motor by a refrigeration load, and to improve a heating maximum capacity at a low outside-air temperature. <P>SOLUTION: During heating operation at a low outside-air temperature, the wet state of a compressor suction side is predicted based on indoor unit heat exchanger temperature (or compressor discharge pressure) and a compressor discharge temperature (STEPs 6, 7). When the wet amount is large and the load is heavy, the timing advance of the motor electric current phase is weakened (STEP 11) and target compressor maximum rotational frequency is set low (STEP 8). When the wet amount is decreased and the load becomes low, a lead angle of the motor electric current phase is increased, (STEP 12) and the target compressor maximum rotational frequency is set high (STEP 9) so as to improve a heating capacity. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
