| 摘要 |
PURPOSE: An apparatus for controlling a power and a method thereof are provided to maintain a constant power of set efficiency, remove an adverse effect on a motor and fast recognize a cycle and a wattage. CONSTITUTION: A period detecting unit detects a frequency relative to a power applied to an input terminal by using a zero crossing method. A wattage detecting unit detects a wattage, which flows a motor when the motor is driven, relative to the power applied to the input terminal by using a light amount. An efficiency setting unit selects an efficiency set according to a kind of the motor relative to a power output to the motor. A micom unit compares values of the period detecting unit and the wattage detecting unit and a value of the efficiency setting unit. A gate trigger unit receives an output of the micom unit and controls a shift of a gate of SCR driving parts. A photo triac which controls a light is used as the gate trigger unit. The wattage detecting unit is electrically insulated by using a photo transistor. |
