The Design Of Anti-Interference Thyristor Trigger Based On FPGA

With the development of power electronic converter technology, the demand ofhigh-quality power supply is increasing. The research and application of the powercontrolled by practical simulating circuits has been developed for many years, but it stillhas some disadvantages. With the rapid development of Integrated circuits and digitalcontrol technology led the field of power electronics control to a higher frequency, lowerloss of consumption trend. Field-programmable gate array (FPGA) integrated circuit is anew type of high integrated circuit appeared in recent years and it has remarkablecharacteristics，such as economy, high-speed, low power, easy to be developed andmaintained. Based on its faster, more integrated, versatile predominance, it comes to thefore from a microcontroller and DSP integrated circuits，and becomes the hot spots ofresearch and application in the current field of power electronics.The controllable DC power supply used in Tokamak power system is most of thepower thyristor phase-controlled rectifier. thyristor trigger the formation unit is animportant part of the thyristor phase-controlled rectifier system. This design uses FPGAcontroller to achieve thyristor trigger digital. Compared with conventional thyristor triggercontrol, it has clearly advantages in the aspects of the pulse symmetry, anti-interferenceability, high precision, and good stability.After comparing to the advantages and disadvantages of the common triggers andanalyzing the effect of thyristor in the rectifier circuit and a variety of performancerequirements for trigger, the design of phase-shift trigger based on FPGA is determined.This program which have simplified the design and improved the stability of the rectifiersystem can achieve high performance control in the case of little external circuit, even if thelogic in the FPGA chip resources is permitted. In this paper, FPGA EP2C8Q became thecore of control commensurate with the trigger circuit when most of the features forphase-shift trigger device have been studied. The main achievement is phase-locked,frequency, pulse and phase control. Also completed a phase-shift trigger external circuits,including phase-reference circuit, the buffer amplifiers and soft start/stop circuit, check the phase loss protection circuits, FPGA control core, gate pulse amplifier and pulsetransformers. On the basis of the above work, the initial realization of the basic functions ofphase-shift trigger.