Рет қаралды 769
Even after more than 25 years of product development, You'd be lucky to get even two years of service from a Chinese made high frequency inverter, especially when powering high inductance loads like full sized refrigerators, large power tools, portable AC units or large microwave ovens. The reason for this is that all of these lightweight, high frequency inverters lack an iron core, copper wound output transformer. Without an output transformer to act as a buffer to absorb the electrical surges provided by the “Flywheel Effect” inherent in the physical amount of a transformer’s iron, these surges and damaging reverse voltage spikes must be handled directly by the inverter’s MOSFET transistors or IGBTs, essentially shortening their life expectancy.
For a more detailed explanation regarding the use of high frequency inverters for charging an EV, please watch Solar Inverter Catastrophic Failure: • Solar Inverter Catastr...
You might be able to start and run some high surge loads when these high frequency inverters are new, but every time you do, you're shortening the life of the MOSFETs or IGBTs in these inverters. To make things even worse, lightweight, high frequency inverters run much hotter than low frequency, transformer-based inverters which makes the low cost, off spec, Chinese made components such as capacitors, MOSFETs, diodes, resistors and ICs that are used in these inverters, far more prone to early failure.
Another major consideration with these lightweight, high frequency, transformerless inverters like is safety. All it takes is for the AC output monitoring circuitry to fail and one of the MOSFETs in the inverter's H-Bridge circuit to short to ground, and these high frequency inverters can send dangerous, high voltage, high amperage DC current straight to your connected AC loads which will not only damage most AC appliances but can also set those AC appliances on fire.
Another consideration that is never mentioned by the high frequency inverter salespeople on youtube, is that the vast majority of these inverters are non-repairable. After the warranty runs out, you're not going to be able to simply ship these units back to the manufacturer in China and have them repair them. And at a typical shop rate of $125 per hour here in the US, with no schematic and limited parts availability, it won't make economic sense to even attempt to repair one of these units.
Once the FETs have fried and have burned a good portion of the inverter's PCB, (And trust me, sooner rather than later, they will fry.) they basically become a brick. Poor man's technology at a rich man's price. A much better choice would be to invest in an inverter or power station that uses low frequency, transformer based technology in its design. Low frequency inverters can handle high surge loads for at least 3x (300%) their continuous rated capacity and they can do this repeatedly, without sustaining damage to their MOSFET transistors, for minutes, rather than the milliseconds that a high frequency inverter offers. That's why the big name brand inverter manufacturers like Schneider Electric, Outback Power, Sigineer Power, Magnum Energy, Victron Energy and others, all use a low frequency topology in their design.