在超导储能系统中换流器与电网相连,使超导储能磁体能够通过换流器与电网进行能量交换,从而实现电网谐波抑制、有功无功补偿等功能。根据超导储能用换流器的特点,结合目前大功率电力电子器件以及电路拓扑的发展趋势,设计了一种结构灵活的换流器控制系统。该控制系统采用数字信号处理器(DSP)与复杂可编程逻辑器件(CPLD)相结合的分离模块式构架设计,在功能上实现了控制系统的算法部分与控制信号产生部分分离、系统的模拟部分与数字部分分离,从而大大提高了控制系统的电气稳定性及系统灵活性。该控制系统还可适用于多种大功率换流设备,因而具有较强的拓展性及通用性。
The converter in superconducting magnetic energy storage (SMES) connects the superconducting magnet and the power system, and provides a path for the electrical power transmission between them. This transmission makes SMES a combination of active power filter (APF), power quality conditioner (PQC) and dynamic voltage restorer (DVR). A flexible control system for the large-scale converters is designed according to their characters and developments. This control system uses digital signal processor (DSP) and complex programmable logic device (CPLD) as its kernel hut separates them into three functional modules. The first module collects analog signals; the second based on DSP carries out arithmetic procedures; the third module based on CPLD generates control signal and PWM pulses. Such structure separates analog part from digital signal part, therefore greatly enhances system stableness and flexibility. This system can also be applied to different converters and work under many conditions.