First, the charging stage

Power input: The energy storage spot welding machine is first powered by the power frequency AC power supply.

Rectifier charging: After the AC is rectified by the rectifier, it is converted into direct current and used to charge the capacitor bank.

Capacitive energy storage: DC power is used to charge a group of high-capacity capacitors through a small power transformer to store electrical energy. This process is the preparation phase that provides the required energy for subsequent welding.

Second, the discharge welding stage

Voltage detection: When the charging voltage of the capacitor reaches the preset set value, the charging process stops. 

Discharge welding: Subsequently, the electrical energy stored in the capacitor is rapidly discharged by a high-power solder mask transformer and converted into a low-voltage, high-energy pulsed current.

Resistance thermal welding: A pulsed current passes through the contact points of the welded workpiece, generating a large amount of resistive heat. This heat causes the metal at the point of contact to melt rapidly, resulting in welding. ：

3. Features and advantages

1. Short discharge time: The discharge time of the energy storage spot welding machine is usually very short, generally not more than 20ms. This means that the welding process is completed quickly, reducing thermal influences such as deformation and discoloration during the welding process.

2. Large instantaneous current: Since the capacitor can store a large amount of electrical energy and release it quickly in a short time, the instantaneous current generated during welding is very large, which ensures the firmness of welding.

3. Stable welding quality: Since the charging will stop charging and transfer to discharge welding after each charging voltage reaches the set value, the welding energy fluctuation is very small, which ensures the stability of welding quality.

4. Wide range of application: The energy storage spot welding machine is suitable for the welding of a variety of materials, including ordinary ferrous metals (such as steel, iron, stainless steel) and non-ferrous metals (such as copper, silver, nickel and other alloy materials), and even welding between dissimilar metals.

5. Energy saving and environmental protection: Because the charging power of the energy storage spot welding machine is small, the impact on the power grid is small, and the discharge time is extremely short, and it will not overheat after long-term use, so there is no need for water cooling, which saves energy consumption.

To sum up, the energy storage spot welding machine realizes the welding of metal materials through two stages: charging energy storage and discharge welding. Its working principle is simple and efficient, and it has the advantages of short discharge time, large instantaneous current, stable welding quality, wide range of application, energy saving and environmental protection.