MOSFET & IGBT Integrated HF welder

MOSFET & IGBT Integrated HF welder from Chaochang is the most advanced new generation induction welder for Mild steel pipe and galvanized tubes. 

Adopting PWM chop-wave technology and Infineon brand IGBT, which could provide fast, stable and adjustable DC voltage & current to the load . It also greatly improve the power factor of the solid state hf welder. 

With Digital Phase-lock loop inverter control technology and the high speed DSP, the fixed angle control is realized and the load frequency can be tracked automatically. It can provide reliable driving pulse for inverter to make sure the induction welder running stable and efficient. 

Introduction of PWM Chop-Wave Technology:

DC Chopper is used to cut the power supply voltage properly to achieve the voltage change of the teminal load. 

Features of PWM Control Technology:

1. There are two option to set machine power, one is constant current, the other is constant power work mode. Customer can choose different ways according to different load. Compared with traditional proportion integral control method, the application of digital control loop composed of microprocessor, fast response, small overshoot, the output power is not affected by power grid voltage fluctuations and load changes, ensure the constant power output. It is of great significance to improve the heating effect and heating coherency. The traditional analog regulator is incomparable. and when the machine working, it adopts constant current mode. 

2. Digital power factor correction is realized by microprocessor, which can reduce the parameter value of filter circuit after diode rectification and make the power factor constant not less than 0.95 (normally it is 0.97 or 0.98).

3. Fast fault protection. It can ensure all failures can be shut off within 10 μS, without causing damage to the equipment.

4. The control circuit has soft start-stop function to prevent the rise rate of current and voltage in the start-stop process too large to cause overvoltage and overcurrent.

Introduction of DPLL Inverter Control Technology

DPLL is short for digital phase-lock loop. we use this technology for second generation H.F. welder inverter control. Previously on First generation welder, we are using the traditional artificial circuit phase lock tech. if you wanna mend the welder datas, under this tech, you have to vary lots of potentiometers, which is quite complicated and hard to show same data again. Also unprofessional person are not allowed to do adjustment.

Artificial circuit phase-lock loop is narrow captured,phase-tracking precision low. DPLL is successfully modify the above disadvantage, also with DSP, it can easily realize the central control system with signal sampling , processing,display, protection etc functions. Also with high speed DSP, we can realize the online phase correction easily.

Comparison of Integrated HF Welder and Old Generation HF Welder