A DSP and FPGA based drive control system for voice coil motor used in direct drive valve

Aiming at the performance requirements of the control system for voice coil motor used in direct drive valve, a hardware structure of voice coil motor drive control system based on float-point digital signal processor (DSP) and field programmable gate arrays (FPGA) was presented. The assignment of the control system was functionally divided into the DSP and FPGA modules according to their structure features. DSP, as the host processor, fulfilled the system functions of self-test and the calculation of position loop. FPGA, as the coprocessor, fulfilled the system functions of PWM signal generation, analog signal detected and digital filtering, over-current protection, communication with DSP and calculation of current loop. Meanwhile, a double-closed loop control composed of position loop and current loop was accomplished. The function modularization design of FPGA was implemented by Very-High-Speed Integrated Circuit Hardware Description Language (VHDL). The simulation and experiment results show the system's validity. The application of FPGA can simplify the hardware structure, release the calculation burden for DSP, and guarantee the real time of the drive control system.