High pressure hoist VVVF system model, performance, Shandong Lee crown Technology Contact: Manager Cao 15953810777, achieved by changing the motor supply frequency speed regulation is an ideal high-efficiency, performance speed control means. 1.1 a few basic definitions of the concept of power factor (1) the definition of the power factor in an AC circuit, the ratio of the average power and apparent power, known as the power factor: where the effective value of the U - voltage (V); I - current RMS (A). 1.2-frequency sinusoidal current power factor Shandong Lee crown of Electronic Science and Technology Co., Ltd. is specializing in the production of high-voltage inverter rig special inverter enhance machine special inverter frequency heating power supply, constant pressure water supply control cabinet, high voltage inverter series, KJPT series Mine explosion-proof and intrinsically safe type inverter, electric submersible pump voltage inverter, a variety of low voltage general purpose inverter and traction network leakage protection, BKT-1 to enhance the comprehensive protection of the WDT-temperature data logging devices, remote power monitoring system, air compressor microcomputer protection device fan remote control system, air compressor remote control system, flameproof electric meter, mobile switches, digital hedging signal device, sound and light language signals, explosion-proof switch calibration station. Concurrently such as mechanical and electrical products, mining accessories, rubber products.