基于DSP和CPLD的有源滤波器数据采集系统设计

针对电气化铁路谐波的要求及其特点,提出了一种基于TMS320F2812双DSP、CPLD以及ADS8556的数据采集系统。整个系统以霍尔传感器和A/D转换器组成前向采集电路,并由CPLD控制A/D转换,其中一个DSP作为主控制器,负责对电网电压/电流及负载侧电流采样、FFT运算以及通过CAN总线接口得到的补偿指令信号传送给单片机产生SPWM信号进行逆变驱动,并将处理得到的数据存储在双口RAM中。另一个DSP作为从控制器从双口RAM中得到数据,实现相应的继电器自动投/切开关及人机交互等功能。本设计被成功应用于电气化铁路智能有源滤波器中,实验表明大大增加了DSP数据采集能力与处理速度,采样精度得到很大的提高,达到了改善谐波补偿效果的目标。

Design of Data Acquisition System Used for APF Based on DSP and CPLD

Based on two DSPs,CPLD and ADS8556,a data acquisition system of a APF is designed,which is applied to electric railway system to compensate the harmonic current.The system takes a Hall sensor system and A/D converters as prior acquisition circuit,then CPLD controls ADC to sample.One DSP fulfill signal sample,FFT calculation,real time control including transmit the calculated compensation circuit signal to microcontroller which can provide SPWM signal to drive inverter,and send the control data into dual-port RAM.Another DSP receives the data from dual-port RAM which is used to fulfill relevant relay auto-switching control and man-machine exchange.The effectiveness of the structure had been verified by the experimental results which show the proposed system greatly improved the capacity of data acquisition and the effect of harmonic compensation with the higher speed of data processing and sample precision.