DSP based high efficiency SR drive with precise speed control

The switched reluctance drive is known to provide good adjustable speed characteristics with high efficiency. However, higher torque ripple and lack of the precise speed control are drawbacks. These problems lie in the fact that SR drive is not operated with an mmf current specified for dwell angle and input voltage. To have precise speed control with a high efficiency drive, SIR drive has to control the dwell angle and input voltage instantaneously. In the paper, a PLL(Phase Locked Loop) technique is adopted to regulate the dwell angle instantaneously. A PLL control technique in conjunction with dynamic dwell angle control scheme has good speed regulation characteristics. The advance angle in the dwell angle control is adjusted to have high efficiency drive through efficiency testing. The F240 DSP based control system is used to realize this drive system. Test results show that the system has the ability to achieve good dynamic and precise speed control.