The Thyristor with Control of Zero Crossover of The Voltage Base on Single-chip
Abstract
Now days in the measure and control system, the old style touch switch has been replaced by SCR gradually. Usually the control method of SCR has two kinds, phase control and zero crossover control ( the voltage of zero, the current of zero). This article introduces the design method with the SCR zero crossover, to be controlled in single chip microcomputer, so as to complement control and measure of temperature with the range of 0~300 ℃ and display the information on status. This article introduces how to determine the moment when the voltage passes the zero value, with the use of technology of the digital PID. The single chip microcomputer triggers the circuit of gate to set out the level of voltage to control the amount of times of thyristor connecting the heating circuit. After determining the parameters of digital PID required, called Zero Crossover control mode of thyristor. In result the opening time of triggered gate circuit is corresponding to the amount of control of the digital PID in analog PID, at the same time this unit present you the design of the hardware and software of the temperature measurement as well as the emulation using the universal software tool of MATLAB. The emphasis is on the thyristor with control of zero crossover of the voltage based on single chip microcomputer and the determent of the parameters of the digital PID.