1. IGBT WELDING TECHNOLOGY
IGBT Welding machine has 3 kinds of technology, which are dual switch forward technology, half bridge technology and full bridge technology. For now, we regularly use half bridge and full bridge for welding machine.
In the market, The 120A around single PCB board machine usually use the half bridge technology, with two transistors. This machine can reduce the cost, but it is low power, low duty cycle which around 20-30%, and low welding effiency. Suitable for DIY.
The normal three PCB machine usually use full bridged technology , great power, high duty cycle. Use 4 transistor. The cost is much high than the single board machine, but high effiency. Suitable for DIY and factory.

2. Dual switch forward technology
This technology is not very good on making the welding machine because its unstable characteristic, and high requirements of the components, we are not regular use this technology for welding, This machine need pay attention on the design details, otherwise, it will be easy damage, and hard to repair.

3. Half bridged technology
The advantage of the half bridged technology is low cost, save the components, simple drive circuit, no need for leak resistance.
The disadvantage is IGBT needs additional absorbing circuit, has through risk because of the Miller effect. IGBT needs more work as the full bridged technology, caused low duty cycle. Regularly, the duty cycle is 20-30% around.
It is very low price in real current 120A and below current. But low duty cycle.

4. Full bridged technology
The advantage of the full bridged technology is High transformer efficiency, high power and the duty cycle can be more than 90%, even 100%. High transformer efficiency.
Disadvantage is that IGBT system needs additional absorbing circuit. It has through risk because of the Miller effect. Needs additional circuit for the transformer to prevent magnet bias.
Requirement of the components is high, complicated circuit.
The cost of the full bridged technology machine is much high than other technology, but it is high power, high duty cycle. But because of the technology, it needs additional circuit to improve the machine’s ability.

5. The difference between Half bridged and Full Bridged technology
From the diagram above , we can see that for 120A machine, the most important difference is the quantity of the transistors. Half bridged use less transistors, and simple drive circuit, so that is why it is less cost. Full bridged machine use 4 transistors, complicated circuit, so it is high power and high duty cycle, but higher cost.
Technology
Half bridged
Full bridged
Transistor 2 4
Drive circuit
simple
complicated
Transformer primary side
Wire diameter thick
More turn number
Input filtering 1
Leak circuit
No need

6. EV MINI machine’s technology and advantage1
Use the stable full bridged technology, the unique radiator design and structure improved the heat transfer, make the machine more stable and high duty cycle. Our mini machine can be 100% duty cycle in normal temperature.
Use the SMT technology, not only save the space inside the machine, but also improve the quality of the machine.
Use the Nano core technology transformer, make the machine more stable and high efficiency.
Use the special two board structure, better heat transfer. Make the machine high duty cycle.
Use the best quality capacity , can make the machine more life and high welding quality, even can work in very low voltage.

7. EV MINI machine’s technology and advantage2
Use 8038 Fan, high speed, good performance and quality, improve the machine efficiency, make the machine more duty cycle.
Intelligent anti-stick function, this function can make the machine to take the electrode from the welding easy when arc broken
Intelligent arc force system, this function can provide the additional current when do the welding process, reduce the arc broken and improve the welding efficiency.
Intelligent hot start function, when the electrode touched the welding board, make the high welding current, improve the arc strike and welding efficiency.
can weld in very low voltage environment, works very well in 160V voltage. Suitable for the unstable voltage are.

8. EV MINI DATA DUTY Electrode No-load Voltage Output current Efficiency
Ø1.6-Ø5.0mm
No-load Voltage
70V
Output current
20-165A
Efficiency
80%
Input current
30A
Force
YES
Antiplastering
Yes
Hot-Start
N.W
2.66kg
Size
26X11X16cm

9. EV MINI DATA Component Supplier Remark IGBT ST 4PCS Diod PEC
Temperature protect
TEMPREL
1PC
Capacity
SINECON
3PCS
Relay
SONGLE
Fan
BISEN
8038
Bridge

10. EV MINI Temperature testing report1
Room temperature 24℃-26℃ Load testing
IGBT1 （℃）
IGBT2（℃）
IGBT3（℃）
IGBT4（℃）
1’ Min 46 41 39 38
2’ Min 53 45 42
3’ Min 57 48 49
4’ Min 59 50 47
5’ Min 60 52
6’ Min 61
7’ Min
8’ Min 51 55

11. EV MINI Temperature testing report2
Room temperature 24℃-26℃ Welding testing
Electrode
IGBT1 （℃）
IGBT2（℃）
IGBT3（℃）
IGBT4（℃）
1st 53 46
42.5 43
2nd 60 49 48 50
3rd 63 51 52
4th
5th 64
6th 66 54
7th 67 55
8th

12. Why EV Welding High Duty Cycle？
From the Testing report1&2 above, we can see that, when the room temperature is 24℃-26℃, The highest temperature of the loading test IGBT is 61 ℃. And the highest temperature of the welding test IGBT is 67 ℃. After 6 minutes, the temperature is nearly stable. The protect temperature is 85 ℃. Testing IGBT temperature is much lower than the protect temperature. So the welding machine will not be protect when in normal room temperature.

13. EV MINI Temperature testing report3
Room temperature 35 ℃，Finally 45 ℃
IGBT1 （℃）
IGBT2（℃）
IGBT3（℃）
IGBT4（℃）
1’ Min 59 57 61 46
2’ Min 66 65 70 50
3’ Min 72 77 69
4’ Min 76 80 74
5’ Min 79 78 81 75
6’ Min 85
7’ Min 82 83 86

14. EV MINI protect room temperature？
From the testing report2, we can see that, when the room temperature from 35℃ rise to 45℃, for the loading test, when reach to 7 minutes, the IGBT temperature is 86 ℃, The machine protect. After 45 seconds, machine temperature reduce, the machine can continue to work.

15. Why EV machine’s price is higher than the single board machine?
For now, in the market, most of the single board machine is belong to the half bridged technology. Usually, this machine’s real current is 100A and 120A. This machine use 2 transistors for low current structure. But 2 transistor can not make high power machine, if increase the power to above 120A, the machine will be overload, even damage. Besides, some bad factory use the recycle (second hands) components for the welding machine, the price is very low, but the products are very unstable. And the life is very short. Customers will complain it.
EV machine promise use the new components for all the machine, great quality. And our machine use the 2 boards full bridged technology. 4 transistors can make the machine more power, even can be 180A real current, even above. Use the best 38 fan. These technology will much improve our machines’ technology. And make the welding machine high quality and high duty cycle, 100% duty cycle.

16. EV machine’s advantage？
Smart, Tiny, Portable , It is only 2.5kg. Can easy carry to work at height.
The machine is smart, but with great power, can weld 5.0mm electrodes. Good efficiency. Suitable for DIY, family factory and big factories.
High duty cycle, can work for long time with no stop protect. Machine will be not protect in normal room temperature. improve the welding efficiency, reduce the working time.
The machine got the intelligent function. Anti-stick, Arc force and hot start, to improve the welding efficiency.