The frequency converter of the winch for handboard tensioner controls the rotation speed of the motor by changing the electrical frequency of the motor stator. The main circuit provides frequency variation power power conversion to the non-synchronous motor, and the types of frequency converter can be divided into 2 types: voltage type frequency converter and current type frequency converter. The voltage type converter converts the DC power of the power supply as AC power, and the current type converter converts the DC point of the power supply into AC power. The filter of DC circuit of voltage type converter is capacitor. The filter of DC circuit of current type converter is inductor. The superiority of the elastic tensioner frequency converter mainly lies in the high control accuracy:The control accuracy of the frequency converter is higher than that of the non-frequency converter, and the speed regulation function of the AC motor is basically equal to that of the DC motor, which can be realized. High operation reliability:The components used in the frequency converter are power electronic components with long life and perfect protection function, which are used in the control of the reel machine with high accuracy and less maintenance work, cutting down the daily maintenance staff. The workload has a wide range of speed regulation and is a stepless variable speed, with good stability at low speeds and a large starting torque of 2 times or more, allowing rotation at low speeds.