Transportation refrigeration unit with ac generator charging of prime mover energy storage device

A method if generating and directing power to a transportation refrigeration unit (TRU) system having a compressor configured to compress a refrigerant, an evaporator heat exchanger operatively coupled to the compressor;

• an evaporator fan configured to provide return airflow from a return air intake and flow the return airflow over the evaporator heat exchanger;
• a return air temperature (RAT) sensor disposed in the return airflow and configured measure the temperature of the return airflow;
• and a TRU controller, the method comprising:
• operably connected to the RAT sensor to the TRU controller;
• determining an AC power requirement for the TRU based on at least the RAT;
• operably connecting a generator power converter, to an AC generator, the generator power converter configured to receive the generator three phase AC power provided by the AC generator and transmit a second DC power;
• operably connecting an energy storage system, the energy storage system operable to receive the second DC power and a three phase AC power, provide first three phase AC power, and received a second three phase AC power;
• and
• operably connecting a power management system to the generator power converter and the TRU, the power management system configured receive the second three phase AC power to direct power the TRU based at least in part on the AC power requirement.