Design On The DSP Based Controller For High-power Frequency-variable High Voltage Device

The series cell topology structure has been becoming a main research tendency in the current high voltage frequency variable field. And so we research and developed a new digital controller for the high voltage frequency-variable motor driving system that based on the series cell topology structure. The controller that based on DSP adopts the way of data transmission to come into being multi-channel SPWM pulse signal, and accomplish the Pulse distribution. The SPWM modulating theory is analyzed, at one time, a new method of simulation online is brought out and the hardware and software are designed in article. Finally, the controller passes through the test.Firstly, it is introduced that includes the high voltage frequency-variable motor driving system's composition and control Strategy. By analyzing several methods to achieve high-voltage inverter and comparing their advantages and shortcomings, The test system platform adopts series cell high voltage frequency variable system topology structure at last. At the same time, by analyzing some theory to achieve high-voltage inverter and comparing their advantages and shortcomings, the v/f is adopted. The v/f is analyzed theoretically.Secondly, the controller's hardware circuits of the high voltage frequency-variable motor driving system is designed based on DSP, including the main controller, phase controller and power unit-driven controller. The corresponding circuit is designed for communication between them. Between phase controllers and power unit-driven controllers, the optical fiber transmission is used. However, the safe and reliable serial communications of simple structure is applied between the main controller and phase controllers. According to above circuit design, it can guarantee the completion of pulse distribution and fault diagnosis functions on the hardware side.Then, the system software is designed. Based on the hardware design, the DSP is programmed by using C language and realized the following functions: the main controller calculates the parameters of the SPWM pulse width and phase controller calculate pulse width after receiving the data parameters. Ultimately, the pulse is produced by power unit-driven controller which collected fault signal from various power unit and transmitted back to the main controller.Finally, the controller completes debugging on the experimental platform. Through the analysis of the experimental waveforms, we can obtain that the controller can be used in the high voltage frequency-variable motor driving system, can produce multi-channel SPWM pulse and achieve fault diagnosis. The system is stable and reaches the design requirements.