With the shortage of resources, all countries are looking for the way to save energy and develop the potential of electric energy-saving. The only way is reduce the consumption.There are many ways for motor energy saving, such as improving motor efficiency, improving power factor, adjusting speed energy saving, Frequency Controlling speed. Now we discuss lowering energy consumption on the motor power factor.

    Asynchronous motor power factor changes with the load. Rated load power factor is higher at rated load, and lowrer and light-load, generally between 0.2 ~ 0.85. Asynchronous motor will draw many emotional reactive power  during operation at power grid, so that the grid power factor deteriorate operation efficiency of system. Reactive power compensation can be taken to adjust. Induction motor reactive power compensation is defined to ensure the normal work of the motor under the premise of power lines through the compensation improve power factor, while reducing power lines and transformer losses.

    Reactive power compensation has: (1) parallel connection capacitor. Motors are usually connected with capacitor at the terminal end of motor. Before no capacitance compensation, the electrical angle of the line electric current lags behind the voltage is larger. After compensate, the electrical angle of the line electric current lags behind the voltage is less, then improve the line power factor. (2) to install power factor static fill device,  which mainly combined by the filtering device and a capacity for stepless adjustment of reactive power equipment. After improving the power factor of the grid , at the guarantee of a constant active power, to make the current system decreased, reducing the loss of power supply system, thereby realize energy saving.