Finding a low-frequency (toroidal) inverter that meets my needs given the models locally available to me in Thailand has been extremely difficult, and I'm beginning to feel it may be impossible. I've been searching/researching for days, and have considered many models, only to be disappointed about one or another of their features. I have found an almost perfect match to what I am looking for in the Deye inverter models, or possibly the Goodwe, but both appear to be high-frequency inverters. My system will need to operate a refrigerator, house fans, and a washing machine, at minimum, with good potential for a future well pump. Inductive load support is vital.
Question: Is it possible to use a standard high-frequency inverter coupled to a suitably sized 1:1 isolating transformer to get the benefits of a low-frequency setup?
Alternatively, I'm all ears to suggestions within the Thai market that would meet the following requirements:
- 220/230 volt inverter
- 48 volt LiFePO4 battery bank, at 300 Ah+
- Quiet (passive cooling / fanless highly preferred)
- Able to operate in hot environment (40-45 degrees Celsius)
- Support 12 LONGi 580-watt panels, at Voc 49.8V and Imp 13.17A per each panel, in two strings of 6 or 3 strings of 4 (with possible Epever CC for 3rd string)
- Between 3kw and 6kw inverter output
- Must be foolproof, e.g. the charge controller and/or inverter will not self-destruct if the PV panels are hooked up without a battery!
- NOTE: Open to using separate charge controller (probably Epever Tracer) and inverter
The best toroidal inverter I seem to find is a no-name brand whose reliability would seem left to chance/good fortune. The "quiet" requirement is important because this will be installed in a meeting room, and there is no closet to sequester the noise.
Most products of this nature are available in Thailand online through one of two sources: shopee.co.th, or lazada.co.th (a subsidiary of alibaba)--both with strong similarities to ebay. Unfortunately, there seems to be no source here for many of the better brands, like Victron, and importing can be a nightmare involving weeks of paperwork, potential fines for not requesting permission to import something beforehand, and taxes that can equal the original cost of the item (been there done that importing a used/for-parts drone purchased off ebay). So scratch all of "the best" off the list, and highlight the rationale for seeking to self-engineer a
