| 摘要 |
<p>Provided is a control method for a variable displacement compressor (8) to control a compression displacement by using a displacement control valve (13) for sensing a differential pressure between a high-side pressure (Pd) and a low-side pressure (Ps) in a cooling cycle (7a). The control method comprises calculating a target duty value (Dt1) of the displacement control valve (13) from a target evaporator blow-out temperature (TMeva) and a real evaporator blow-out temperature (Teva), calculating a drive torque (Trq2) of the compressor (8) at the instant when it is assumed from the high-side pressure (Pd) that the variable displacement compressor (8) is in a full stroke state, as the upper-limit drive torque (Trq2), calculating an estimated drive torque (Trq1) of the compressor (8) from a real control current value (Isolc), setting the target duty value (Dt1) as an output duty value (Dtc) in case the estimated drive torque (Trq1) is less than the upper-limit drive torque value (Trq2), and sets a duty value (Dt2) calculated from the upper-limit drive torque (Trq2), as the output duty value (Dtc) in case the estimated drive torque (Trq1) is the upper-limit drive torque value (Trq2) or more.</p> |
