Abstract:Fan pitch control backup power supply can make the blades retract smoothly under the action of the variable pitch control system to avoid accidents when the fan has a power failure.In this paper, aiming at the existed problems of the fan pitch control backup power supply system, an emergency backup power supply scheme is designed adopting super-capacitor energy storage module and bidirectional DC/DC converter charge-discharge control.It has the advantages of wide operating temperature range, being eco-friendly and easy to realize remote monitoring of the state, which improve the reliability and stability of the fan operation and save the construction cost.The capacity selection of super capacitor, simple and effective voltage-sharing scheme and circuit, as well as double closed loop control strategy are discussed in this paper.The effectiveness of the scheme is verified by simulation test and actual measurement results.