老外哪里爬来的 开源的 内含电路图
简单使用可以不要屏幕直接在程序里改参数 接个开关和固态继电器就可以用了
电路说明这里有点不理解那位大神解释下 论坛里变压器做点焊机都是用双向可控硅或固态继电器控制初级电流 这里用的是两个普通单向可控硅
Solid state relays with standard TRIACs will not work here, because the load is highly inductive. Standard TRIACs have turn-off problems with inductive loads, while SCRs always turn off at the negative half-cycle. Therefore, an antiparallel back to back connected thyristor control is used here. The RC snubber network R11 and C3 protects the circuit from voltage transient spikes. D1 and D2 are transient-voltage-suppression diode (TVS), without this diode the ATMEGA328 may be damaged by voltage spikes.
The current through the weld transformer, which is an inductive load, will lag behind the voltage by 90o. This is the reason that, to reduce the inrush current, the optimal switch-on time is not the zero point of the mains sinus but the top of the sinus. To be able to do this, the Arduino has to detect the mains zero crossings, this is done by R5 and C6. The two internal clamping diodes of the ATMEGA328 limit the input voltage to 0 and 5V. The delay time in the software "sinusMax_us" is 4583μs, this strange number is the average of 1/4 cycle of 50Hz and 60Hz.
