Funtions

The Universal Power Supply should provide these functions:

Inverter
Solid state transformer - 1200V, short range transmission lines - $60 cost of 45 kW transformer. [1]
Induction furnace
Plasma cutter
Welder
Laser cutter
Charge controller to batteries
Power conditioning from a windmill
Induction heater
Contactor
Electric motor speed contoller
Stepper motor controller

Part Reduction

What is the minimum number of electronic parts required to build the Universal Power Supply?

Arduino for control. Arduino can also measure frequency to 50kHz for feedback - [2]
IGBTs - choose one that can be scaled extensively, 10kW range (20A x5, 100V)
Resistors
Capacitors (filters)
Small transformers
Current sensors - Hall Effect Sensors
Terminal blocks, 50A [3]
Wire (8 ga, 55A, 600V) [4]
Switches. Small switches, with IGBT serving as larger switch or contactor
200A contactor relay - 48DC - [5]
Go for 600V on components, at 50A for wires, need 7 wires for 210kW - manageable as a modular system

Arduino does it - [6]
Modified Sinusoidal pulse width modulation - http://www.theorycircuit.com/arduino-inverter-circuit/