| 摘要 |
PURPOSE:To save power consumption by setting phase control conditions for minimizing a consumption current, increasing a phase angle when a load is increased to increase the current, and decreasing the angle when the load is decreased to decrease the current. CONSTITUTION:A single-phase power source 9 for supplying power to an induction motor 2 is phase-controlled by a TRIAC 3. The gate 13 of the TRIAC 3 is set to an arc phase angel by a resistance value connected to the phase control terminals 41, 42 of a phase controller 1, and the motor 2 is phase- controlled. In this phase controlling method, the phase control conditions for minimizing the consumption current under predetermined load condition is set, a load change is detected by the change of the current flowing to the motor 2, the phase is so controlled that the phase angle is increased when the load is increased to increase the current, while the angle is decreased when the load is decreased to decrease the current. Thus, since the motor 2 is operated with the minimum current in the load state, power consumption can be saved. |
