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I have a 220 V 100 hp electrical motor.

I initially had a plan to use the grid 110 V through a step up transformer to get to 220 V along with a 480 kVA capacitors to kick start the 3 phase 100 hp motor. This would power all the smaller equipment but mostly a 50 hp motor for pumping.

I no longer have access to the 110 V grid system. Let's say that I have a suitably large battery bank with 480 kVA capacitors in parallel.

Would I be able to use an inverter from the battery/capacitor bank to still kick start the motor and generate stable 3 phase power?

solar -> mppt -> [_x battery bank] + [13 480 kVA capacitors] plus inverter to run the 100 hp motor?

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    \$\begingroup\$ Are you saying that you are going to drive the motor with the inverter and at the same time use it as a generator to power the smaller equipment and a 50 HP (37.5 kW) pump? Or are you trying to mechanically drive the pump using this motor via drive belts or similar? This seems most unlikely. \$\endgroup\$ – Transistor May 6 at 15:12
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    \$\begingroup\$ Assuming that you have 50kW+ of solar available, you should just get an inverter that'll supply you with 50kW of three phase at a suitable voltage. \$\endgroup\$ – TimWescott May 6 at 15:17
  • \$\begingroup\$ @Transistor I wanted to use the solar to drive 100hp to generate stable 3 phase \$\endgroup\$ – soular May 6 at 15:24
  • \$\begingroup\$ @TimWescott I have over 200 310volt panels so the wattage shouldn't be an issue. I wasn't sure if I could get both single phase 110v for normal equipment and 3 phase 220v for the more heavy duty equipment. Are there inverters like that? \$\endgroup\$ – soular May 6 at 15:25
  • \$\begingroup\$ So you are trying to make a setup to use the motor as a motor and as a generator? \$\endgroup\$ – Transistor May 6 at 15:26
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For powering 3-phase motors, it is probably best to use motor-control inverters, also known as variable frequency drives (VFDs). They can start the motors with no or very little extra current required during starting. You should be able to find VFDs that will accept 300 V dc input.

It sounds like you may have been planning to use the 100 Hp motor as part of a phase converter setup. You wouldn't need that, but you would need a VFD for each 3-phase motor. It is possible to use one VFD for more than one motor if the motors would always be running at the same time. If only one motor is running and you need to add another, you would need to stop the first motor, connect the second and restart both.

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  • \$\begingroup\$ Yes and 100 Hp VFD’s are about $4k gohz.com/100hp-vfd or get smaller ones for each task. But then what to do with the idle 100Hp motor (hmm) \$\endgroup\$ – Sunnyskyguy EE75 May 6 at 17:06
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I would recommend you to use mppt vfd unit for 50hp motor. This also eliminates need for rotary converter with capacitors. Be carefull, do NOT connect capacitors across VFD output, beacouse most VFD have a PWM output, saving on output filter. Btw all the smaller eqipment will have to be powered separatelly( anouther part of solar panels -> mppt charger -> battery bank -> inverter -> ( maybe transfor for 110 /220) -> loads.

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