When it comes to inverter spot welding machine, the first thing to say is the circuit structure of inverter spot welding machine. The circuit structure of the inverter spot welding machine generally adopts the process of rectification-inversion-re-rectification, that is, AC-DC-AC. Due to the high working frequency in the inverter process, the statistical characteristics of the dynamic characteristics of the control process are improved, and the welding machine is small in size and light in weight.
The inverter inverter welding frequency is generally above 100KHz. The weight of the transformer is reduced. Now the core material of the transformer spot welding machine transformer is mainly ferrite and microcrystalline material. The small power inverter spot welding machine has entered the family as a tool. The weight of the transformer in the traditional spot welder accounts for more than half of the weight of the spot welder, and the weight of the transformer in the inverter spot welder is 1/5 to 1/10 of the weight of the spot welder. The weight of the inverter welding machine is 1/2 to 1/4 of the same capacity rectification welding machine.
It is precisely because the operating frequency of the inverter spot welding machine is above 100KHz that the droplet transfer can be subdivided into multiple stages for control. For CO2 gas shielded welding, it can greatly reduce spatter, and extremely inert / active gas shielded welding (MIG / MAG) for pulse melting, which can effectively control the stability of jet transition, and can also transfer droplet transfer and wire feeding Combined with the motion, one-step control of the droplet transition process. These are not possible with traditional rectifier spot welders.
The inverter gas shielded welding control circuit has the following characteristics:
① The given system (voltage, wire feed speed) on the wire feeder is linearized, which eliminates the shortcomings of small specifications that are difficult to adjust.
② Synchronized precision rectification is performed on the voltage and wire feeding (current) speed given signals after system demodulation, which eliminates the phenomenon that the given signals are disturbed in the case of large-size long wires (arc closing) of such welding machines.
③ The waveform control circuit is optimized, which greatly reduces welding spatter under short-circuit transition, thereby improving welding quality.