Development Of Integrated Power Storage Battery Management System

Integrated power supply consists of the AC power supply, the DC operation power supply, DC converter, AC uninterruptible power supply, inverter power supply(according to the need of the project selection) and other power equipments which can unified monitoring control in Substations or power plants. They are no longer separate equipped with batteries, but shared storage batteries of DC power supply. Therefore, the batteries as a backup power when AC power failure occurs, its stability directly affects the production and operation of the substations or power plants.In recent years, lithium battery is widely used in various fields because of its small volume, light weight, long service life, high safety, fast charge, no memory effect and many other advantages. Due to lithium battery is limited by its own characteristics and the performance of on-line monitoring device, the actual service life of the battery is not ideal. If battery life is not ensured, it would pose a great security risk of power grid system, at the same time, a large number of scrap batteries also caused a serious waste of resources and increased environmental pressures. Just the current situation of the batteries in power system, this paper uses battery monitoring chip LTC6803 of Linear Technology Company and ST Company’s 32 bit microcontroller STM32F105 to design a battery management system(BMS) with a high precision and reliability.Firstly, this paper introduces the characteristics and advantage of lithium battery and analyzes the common fault mechanism. And it put forward a kind of Kalman filtering algorithm to estimate the state of charge(State of Charge, SOC). Then the paper introduces the hardware circuit and software design of each function module in detail. This BMS is the master-slave structure, which include a Central Battery Managing Unit(CBMU) and some Central Battery Managing Units(BMU). In addition, there is further study in this paper not only on current collection and insulation detection in CBMU, but also on single battery voltage detection and battery balance management in BMU.The results of test show that, the device can perform real-time monitoring and data analysis of the voltage, charge or discharge current, temperature and SOC value. Moreover, it can timely alarm when the batteries is in a non normal state, so as to ensure the safety of batteries and prolong the service life of them.