Power management system for a transport refrigeration unit

A method of powering a transport refrigeration unit, the method comprising:

• mechanically driving a generator using an engine, wherein the generator is mechanically connected to the engine;
• supplying electrical power generated by the generator to a battery unit;
• and
• supplying electrical power to the transport refrigeration unit using the battery unit, responsive to a power demand of the transport refrigeration unit;
• wherein the generator is coupled to the engine via a clutch;
• the method further comprising:
• monitoring a power level of the battery unit;
• determining that the vehicle is in a fourth state and disengaging the clutch when the vehicle is in the fourth state, wherein the power level of the battery unit is below a first threshold in the fourth state;
• and
• determining that the vehicle is in a fifth state and engaging the clutch when the vehicle is in the fifth state, wherein the power level of the battery unit is above a second threshold in the fifth state;
• wherein the second threshold is higher than the first threshold.

A method of powering a transport refrigeration unit, the method comprising:

• mechanically driving a generator using an engine, wherein the generator is mechanically connected to the engine;
• supplying electrical power generated by the generator to a battery unit;
• and
• supplying electrical power to the transport refrigeration unit using the battery unit, responsive to a power demand of the transport refrigeration unit;
• wherein the generator is coupled to the engine via a clutch;
• the method further comprising:
• monitoring a speed of the vehicle;
• determining that the vehicle is in a first state and engaging the clutch when the vehicle is in the first state, wherein the speed of the vehicle is increasing in the first state;
• and
• determining that the vehicle is in a second state and disengaging the clutch when the vehicle is in the second state, wherein the speed of the vehicle is substantially constant in the second state.