- #1
BernieM
- 281
- 6
Living in a remote desert location, I have to generate my own power from solar. Big loads require big inverters, and for me sine wave is a must, not modifieed sine. Higher voltage inverters allow more batteries in a string meaning more storrage capacity in that string and since multiple parallel strings don't charge well, a large capacity single battery or string is better than smaller parallel arrays.
Big sine wave inverters are expensive. So while considering the problem, I hit upon what at first glance seems to be a simple and effective solution. Namely, put sufficient batteries in series to reach the desired a/c voltage and then using a simple and inexpensive waveform generator, drive a large power transistor or series of them to provide the wattage capacity desired. It should be clean enough as far as power goes to be usable without much waveform conditioning I would think.
With 12 volt batteries, for example, 10 of them when fully charged will be at 126 volts and when drained still be at 108 volts, nearly 110 volts, though one wouldn't want to let them get that far drained. Probably cut out when they reach 11.2 volts or so, or 112 volts on a chain of 10. With my 24 volt inverter, the maximum number of 12 volt batteries I can put in a string is 2, with 6 volt batteries, 4. With this method I can use ten 12 volt batteries or 20 6 volt!
OK so what am I missing? I get a sneaking suspicion that someone is going to mention the down sidde that I'm overlooking. Ok so have at it! Is this a good solid solution or should it be filed in file 13?
Big sine wave inverters are expensive. So while considering the problem, I hit upon what at first glance seems to be a simple and effective solution. Namely, put sufficient batteries in series to reach the desired a/c voltage and then using a simple and inexpensive waveform generator, drive a large power transistor or series of them to provide the wattage capacity desired. It should be clean enough as far as power goes to be usable without much waveform conditioning I would think.
With 12 volt batteries, for example, 10 of them when fully charged will be at 126 volts and when drained still be at 108 volts, nearly 110 volts, though one wouldn't want to let them get that far drained. Probably cut out when they reach 11.2 volts or so, or 112 volts on a chain of 10. With my 24 volt inverter, the maximum number of 12 volt batteries I can put in a string is 2, with 6 volt batteries, 4. With this method I can use ten 12 volt batteries or 20 6 volt!
OK so what am I missing? I get a sneaking suspicion that someone is going to mention the down sidde that I'm overlooking. Ok so have at it! Is this a good solid solution or should it be filed in file 13?