Battery power management systems and methods for engine off

An air conditioning system of a vehicle having an internal combustion engine, comprising:

• an electric compressor;
• a condenser that is configured to receive refrigerant output by the electric compressor and that transfers heat from the refrigerant within the condenser to air passing the condenser;
• a fan that is configured to blow air across the condenser;
• a first control valve;
• a first evaporator that is configured to receive refrigerant from the condenser when the first control valve is open and that transfers heat from air passing the first evaporator to the refrigerant within the first evaporator;
• a first blower that is configured to blow air across the first evaporator to a first section of a cabin of the vehicle;
• a second control valve;
• a second evaporator that is configured to receive refrigerant from the condenser when the second control valve is open and that transfers heat from air passing the second evaporator to the refrigerant within the second evaporator;
• a second blower that is configured to blow air across the second evaporator to a second section of the cabin of the vehicle;
• a control module that is configured to, when the internal combustion engine of the vehicle is off, the electric compressor is on, and the second blower is on and blowing air across the second evaporator:
• determine a compressor speed command;
• and
• control a speed of the fan based on at least one of:
• a power consumption of an inverter drive;
• a compressor discharge pressure;
• and
• a speed of the electric compressor;
• and
• wherein the inverter drive is configured to apply power to the electric compressor based on the compressor speed command.

An air conditioning control method for a vehicle having an internal combustion engine, comprising:

• determining whether the internal combustion engine of the vehicle is off,
• wherein a first evaporator is configured to receive refrigerant from a condenser when a first control valve is open and to transfer heat from air passing the first evaporator to the refrigerant within the first evaporator,
• wherein a first blower is configured to blow air across the first evaporator to a first section of a cabin of the vehicle, and
• wherein the condenser is configured to receive refrigerant output by an electric compressor that draws power from a battery pack and to transfer heat from the refrigerant within the condenser to air passing the condenser;
• determining whether the electric compressor is on;
• determining whether a second blower is on and blowing air across a second evaporator,
• wherein the second evaporator is configured to receive refrigerant from the condenser when a second control valve is open and to transfer heat from air passing the second evaporator to the refrigerant within the second evaporator, and
• wherein the second blower is configured to blow air across the second evaporator to a second section of the cabin of the vehicle;
• when the internal combustion engine of the vehicle is off, the electric compressor is on, and the second blower is on and blowing air across the second evaporator, controlling a speed of the electric compressor based on at least one of:
• a temperature of the second section of the cabin of the vehicle;
• and
• a speed of the second blower;
• and
• based on a current of the electric compressor, determining whether to control the speed of the electric compressor:
• based on the temperature of the second section of the cabin of the vehicle;
• or
• based on the speed of the second blower.

An air conditioning control method for a vehicle having an internal combustion engine, comprising:

• determining whether the internal combustion engine of the vehicle is off,
• wherein a first evaporator is configured to receive refrigerant from a condenser when a first control valve is open and to transfer heat from air passing the first evaporator to the refrigerant within the first evaporator,
• wherein a first blower is configured to blow air across the first evaporator to a first section of a cabin of the vehicle,
• wherein the condenser is configured to receive refrigerant output by an electric compressor and to transfer heat from the refrigerant within the condenser to air passing the condenser, and
• wherein a fan is configured to blow air across the condenser;
• determining whether the electric compressor is on;
• determining whether a second blower is on and blowing air across a second evaporator,
• wherein the second evaporator is configured to receive refrigerant from the condenser when a second control valve is open and to transfer heat from air passing the second evaporator to the refrigerant within the second evaporator, and
• wherein the second blower is configured to blow air across the second evaporator to a second section of the cabin of the vehicle;
• and
• when the internal combustion engine of the vehicle is off, the electric compressor is on, and the second blower is on and blowing air across the second evaporator:
• determining a compressor speed command;
• and
• controlling a speed of the fan based on at least one of:
• a power consumption of an inverter drive;
• a compressor discharge pressure;
• and
• a speed of the electric compressor;
• and
• wherein the inverter drive is configured to apply power to the electric compressor based on the compressor speed command.