Batt Back AC or DC Motor?
Batt Back AC or DC Motor?
(OP)
I have designed a 1HP VFD. I now need battery backup motor control for the same power range. I also have a solar requirement which keeps the battery voltage at 12V (24V solar is an option but less popular). I have two options:
1. 'Step-up' the battery voltage to the VFD DC voltage through an inverter.
2. Design a 12 DC motor control.
Both have advantages and disadvantages. I plan to use a PM-SCR type motor for the DC approach. My research has produced some questions:
1. Why are 90 and 180V PM motors so popular?
2. What is the difference in price from a 1HP AC induction and an equivalent PM-SCR?
3. Is the ‘Brushed’ Motor that much less reliable?
Any feedback is very much appreciated!
1. 'Step-up' the battery voltage to the VFD DC voltage through an inverter.
2. Design a 12 DC motor control.
Both have advantages and disadvantages. I plan to use a PM-SCR type motor for the DC approach. My research has produced some questions:
1. Why are 90 and 180V PM motors so popular?
2. What is the difference in price from a 1HP AC induction and an equivalent PM-SCR?
3. Is the ‘Brushed’ Motor that much less reliable?
Any feedback is very much appreciated!





RE: Batt Back AC or DC Motor?
Just curious as to the application. You will need quite a large battery to run a 1 hp motor (746 watts is 62 amps at 12V) for any length of time. This would also be a large solar array - even when the sun is shining.
RE: Batt Back AC or DC Motor?
TTFN
RE: Batt Back AC or DC Motor?
The application is controlling a gate. There are a lot of different power requirements. Not all will need solar, but all will need battery backup (as an option). Solar panels would only be used on fractional HP model. I mention the solar cell only because it limits me from connecting 4 batteries in series and using a 90V motor at half speed when in battery mode.
In reference to using a 12V (automotive) motor – The battery is actually an option. I will need to operate the motor without a battery also.
RE: Batt Back AC or DC Motor?
RE: Batt Back AC or DC Motor?
I have designed a 1HP VFD.
///Congratulations! Please, would you post its principle of operation?\\\
I now need battery backup motor control for the same power range. I also have a solar requirement which keeps the battery voltage at 12V (24V solar is an option but less popular). I have two options:
1. 'Step-up' the battery voltage to the VFD DC voltage through an inverter.
///DC voltage is normally stepped-up (or -down) by DC-DC converters. The inverter normally inverts DC to AC.\\\
2. Design a 12 DC motor control.
Both have advantages and disadvantages. I plan to use a PM-SCR type motor for the DC approach. My research has produced some questions:
1. Why are 90 and 180V PM motors so popular?
///This is probably linked to the voltage resulting from energy conversions.\\\
2. What is the difference in price from a 1HP AC induction and an equivalent PM-SCR?
///Visit
http://www.thomasregister.com
and type Motor or Drive or what you actually have in mind under Product or Service. This will return companies that you can directly contact for info.\\\
3. Is the ?Brushed? Motor that much less reliable?
///It depends on its maintenance and application.\\\
Any feedback is very much appreciated!
RE: Batt Back AC or DC Motor?
"Principal of operation" -> VFD = varies motor speed. Application = Gates.
"DC to DC Converter" -> Add a rectifier to an inverter and you get a DC to DC Converter.
"It depends on its maintenance and application." -> What application is a brushed motor more reliabale?
RE: Batt Back AC or DC Motor?