Research On Flywheel Energy Storage Control System

Flywheel energy storage (FES) is an advantageous type of late-model energy storage technology, which can be got from solar energy, wind energy and excess electrical energy of power network as the supplementary energy source. The system is high efficient, secure, green and economic. At present, FES technology has been successfully applied in many fields such as aerospace, electric power systems, hybrid electric vehicles, etc. Distributed energy system based on FES is an effective method to optimize electric power system and improve the utilization rate of electricity networks. If the method can be widely used, 20%~30% of city power supply would be solved. Thus, it has high significance.The research is a part of previous research of independent distribution energy system which is an important technology project in Shenzhen. The electronic elements and control system, which are the key components of energy conversion in FESS,are mainly discussed in this dissertation. After referring to a lot of domestic and foreign papers about FESS and analyzing the structure, principle, work mode and control methods of FESS, a solution based on the TMS320F2812 is proposed and initial system hardware circuits are designed in this dissertation. In order to finalize the design proposal of hardware and software, the simulation software of MATLAB has been used for FES system. Finally, an experimental prototype is developed.In charge section, electrical energy is converted into mechanical energy by flywheel which is motivated by brushless DC motor (BLDCM). In order to reduce start-up current and torque ripple,the whole system combines pulse amplitude modulation (PAM) control method with pulse width modulation (PWM) control mode of three phases inverter circuit. At the same time, In order to obtain a FES control system of high performance, a dual closed-loop full-digital control system is designed using speed and current as control objects. In discharge section, FESS can be converted mechanical energy into electrical energy, and a boost converter is introduced to stabilize the bus voltage value about 310 V, then the DC bus voltage is inverted to 220 VAC by an inverter circuit which is applied with SPWM method. The experimental and simulation results show that the system is reasonable and reliable. In a word, this research implemented the expected ideal, and laid a good foundation for the next stages of product development.