Transportation refrigeration unit with external DC generator power source

A transportation refrigeration unit (TRU) and power system comprising:

• a compressor configured to compress a refrigerant, the compressor having a compressor motor configured to drive the compressor;
• an evaporator heat exchanger operatively coupled to the compressor;
• an evaporator fan configured to provide a 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 to measure a temperature of the return airflow;
• a TRU controller operably connected to the RAT sensor and configured to execute a process to determine an alternating current (AC) power requirement for the TRU based on at least the RAT sensor;
• a power management system the power management system configured to receive a second three phase AC power from a generator power converter;
• wherein the power management system directs power to the TRU based at least in part on the AC power requirement;
• an energy storage system configured to provide or receive a three phase AC power to/from the power management system;
• wherein the power management system includes a power control switching device, the power control switching device responsive to the TRU controller and configured to direct a plurality of power flows in the TRU and power system;
• wherein a portion of power flows of the plurality of power flows comprises:
• receiving the three phase AC power from the energy storage system and receiving the second three phase AC power;
• synchronizing and combining the three phase AC power from the energy storage system and the second three phase AC power;
• and
• directing the combined three phase AC power to the TRU in response to the TRU being operative and an energy storage device of the energy storage system exhibiting a state of charge greater than or equal to a selected threshold.