| 摘要 |
PURPOSE: A power saving driver circuit for electric motors is provided to prevent switch-on loss and to reduce costs by replacing an inductor with an electric motor coil. CONSTITUTION: A first switching element(S1) operates an electric motor(20) during the positive sinusoidal wave period of an input power source. A diode(D5) charges a power factor compensation condenser(C) when the first switching element is off. A second switching element(S2) operates the electric motor during the negative sinusoidal wave period of the input power source. Another diode(D6) charges the power factor compensation condenser when the second switching element is off. A fourth switching element(S4) operates the electric motor with the discharge current of the power factor compensation condenser during the positive period of the input power source. A third switching element(S3) operates the electric motor with the discharge current of the power factor compensation condenser during the negative period of the input power source. [Reference numerals] (AA) Phase detecting signal of input power; (BB) Manipulation signal; (CC) Sensing signal of charging voltages; |
