针对采用DSP实现空间矢量脉宽调制算法存在的时序错乱、相位抖动的问题,提出了一种基于FPGA实现变频控制的新思路.结合空间矢量脉宽调制(SVPWM)技术,采用DDS算法代替传统的DSP,产生SVPWM的正弦电压调制信号,并对传统的SVPWM算法进行了优化设计.在利用五段式原理进行空间电压矢量合成时,对开关矢量时间进行分配与重构,减少了FP—GA逻辑单元的占用率.最终利用QuartusⅡ进行软件仿真分析,并在实际硬件电路中进行了实验验证.实验结果表明,提出的SVPWM信号发生算法实时性好、可靠性高,可实现精确的变频调速,满足一般变频控制系统的要求.
To solve the problems of timing disorder and phase jitter existing in the space vector pulse width modulation(SVPWM) realized by digital signal processor (DSP), a new idea is put forward for the frequency control system based on field programmable gate array (FPGA). Combining the SVPWM, direct digital synthesizer (DDS) is used to generate sinusoidal voltage modulation instead of DSP and the traditional SVPWM algorithm is optimized. Furthermore, the switching vector time is allocated and reconstructed when the fivestyle principle is utilized to synthesize space voltage vec tor, which reduces the occupancy rate of logic units for FPGA. Finally, the algorithm is simulated in Quartus Ⅱ and verified by experiments. The experimental results show that the proposed SVPWM algorithm is realtime and reliable, and it can be used to achieve precise frequency control, which meets the requirements of the variable frequency control system.