Farad capacitor pulse spot welding machine

Project description
Farad capacitor spot welding machine, limit instantaneous current 5.4KA voltage 5V, adjustable output pulse time, with contact protection, adjustable continuous mode and semi-automatic mode. The related functions
 
of the open source agreement
GPL3.0
project
can adjust the output pulse time and continuously adjust the welding power.
 
Project Properties
This project is public for the first time and is my original project. The project has not won any awards in other competitions.
 
Project progress
Hardware testing and software debugging have been completed.
 
The design principle
uses a microcontroller to accurately control the output time of the power field effect transistor, and the display voltage time setting
 
software instructions are shown
in the attachment.
 
Physical display.
Precautions for production.
It is recommended to use copper rows for bold areas of PCB field effect tubes. Welding The two wires of the pen must be as thick as possible, short in length, and run side by side. It is recommended to use pure copper 10 to 16 square meters soft wire. It is recommended to use a special soldering pen for spot welding machines (I use an electric soldering iron tip as a soldering pen and the tip always sticks). If the wires are not routed side by side and the wire diameter is not thick enough, the reverse electromotive force generated by the inductance of the wire will break down the microcontroller and Screen (5 microcontrollers and 3 screens were burned due to this reason during debugging).
 
Others: Functions and operations
When plugging in, the initialization interface is first displayed and then the operation interface is entered. In the ready state, all operation keys are locked except the start button. When the welding pen touches the workpiece, all operation keys are locked (you cannot switch to the preparation mode and modify the welding parameters while the welding pen is in contact with the workpiece). In single mode, you need to press the start button to restore the startup state after each welding, but in continuous mode, it is not required. Operation instructions: Touch the switch to switch between preparation mode and cancellation mode. Press the encoder button to switch to single mode or continuous mode. The time of the left-turn encoder decreases and the time of the right-turn encoder increases. The time adjustment range is 0~99ms. (Spot welding time reference, nickel strip 18650 battery electrode spot welding voltage 4.8V, pulse time 40ms Nickel strip spot welding nickel strip voltage 4.8V, pulse time 25ms) Welding operation actual test video: *https://www.bilibili.com/video /BV1Bo4y1q795/