Design And Implementation Of Vanadium Battery Backup Power System

With the increasing electricity demand of people, the electricity blackouts of a wide range often happens around the world. Due to the instability of solar, wind and other new energy generation, the energy saving and efficient use, and users’ expectation of continuing work of the load, the reserve of energy becomes increasingly important.Due to the high efficiency, long life and other advantages of vanadium battery, the study of backup power of vanadium battery has important practical significance.In this paper, the design and implementation of the vanadium battery backup power system will be completed. First, the design structure of the whole backup power of vanadium battery is introduced. Then according to the syetem design, the structure and function of vanadium battery, lead-acid battery and control cabinet which the system contains are introduced. According to the energy supply and demand status among the vanadium battery, lead-acid battery and the load, a variety of control process of the system are put forward, including the grid gives power supply to the load; the grid gives power supply to charge the battery, the battery gives power supply to the load, and vanadium battery unloading.Secondly, according to the requirement of design, the energy storage and power supply circuit structure of the whole system is put foward. Among of those circuit stucture, the three-phase interleaved stucture is adopted in vanadium battery charge and discharge circuit, the half bridge structure is adopted in lead-acid battery charge and discharge circuit and the three-phase half bridge structure is adopted in rectifying and inverting circuit. In order to make the system works more efficient and stable, the corresponding control strategy will be used into the circuit control, such as SVPWM control, PI control etc.Thirdly, according to the control process and strategy analysis of the desired control system, some corresponding software design has been completed. Based on the program development of digital signal processing(DSP) and field programmable gate array(FPGA), it have achieved the normal open and close of the contactor of system in the process of the different working mode automatically, and also have gatherd and analysed a variety of data, completed the real-time monitoring of the working state of all kinds of devices and data such as current, voltage and other in the system working condition. When the system works abnormally, it can achieve the emergency stop.Finally, after the debugging and test of the system in the field, the buckboost and rectifier and inverter test of battery have been completed on the basis of system requirements. The result of the test shows that the design of vanadium battery backup power system can achieve the basic requirements, it has a feature of reliability, security and stability.