Research on Integrated Application and Charging-discharging Control Method for the Magnetically Suspended Flywheel Storage-based UPS System

For the disadvantages of the chemical battery in the traditional ups system, this paper focuses on the ups system based on the magnetically suspended flywheel. Considering the property of the permanent magnet synchronous motor, the sensorless charging-discharging control strategies of the flywheel based on the extended sliding mode observer are established. Firstly, the system mode and observer scheme are designed, and based on this, a kind of parameter online accommodated method by using the DC-bus link voltage measurement is proposed in order to improve the rotor angle estimation accuracy. Then, the fast transmit strategy between the process of charging and discharging is given. Finally, the proposed control strategy is applied into the real system. The experimental results show that the flywheel ups system can work well with a excellent estimation performance of the observer, with which a fast charging-discharging process can be achieved.