AC-DC Conversion Device Controller To Achieve Intelligent Triggering Unit

In the practical application process of AC-DC conversion device controller, in order to improve the reliability of its operation, to realize intelligent control, thyristor normal work necessary for high performance intelligent digital trigger has increasingly become the research focus of technical personnel.In this paper, the development and trend of thyristor trigger are analyzed in detail, combined with the strong demand for high-performance digital thyristor trigger, developed a set of realization pulse phase shift, phase sequence adaptation, lack of protection, overvoltage, overcurrent, external fault protection, human-computer interaction, and other functions in one of the AC-DC conversion device controller, according to the working principle of the intelligent digital trigger for the three-phase bridge controlled rectifying system, using CPLD chip and VHDL language programming method is proposed based on adaptive sequence, implemented in software phase protection, external fault protection, trigger pulse generation, double narrow pulse forming capabilities. Meanwhile, the thyristor digital trigger pulse modulation frequency, double narrow pulse width, firing angle accuracy can be changed according to the actual needs of the software, greatly improve the reliability and flexibility of the trigger system.Throughout the control unit also adds fuzzy adaptive PID control, touch screen display, online debugging functions. In this paper, the implementation of the intelligent trigger unit based on CPLD is introduced, and the hardware debug and software simulation are carried out, the experimental waveforms and simulation results show that the thyristor digital trigger system can accurately generate a trigger pulse having a good symmetry and stability, also to ensure reliable operation of the three-phase bridge controlled rectifier system.