Additional cooling pack with fans to handle and peak shave fuel cell transients and high ambient temperatures

A method for cooling fluid temperature control of a primary power source cooling fluid for a primary power source of a work machine, wherein the work machine includes a primary power source cooling unit having a primary unit inlet port fluidly connected to receive the primary power source cooling fluid from the primary power source, and a primary unit outlet port, and wherein the work machine includes a secondary power source cooling unit fluidly connected to the primary unit outlet port to receive the primary power source cooling fluid from the primary power source cooling unit, and a secondary unit outlet port fluidly connected to discharge the primary power source cooling fluid to the primary power source, the method comprising:

• comparing a primary cooling fluid temperature of the primary power source cooling fluid at the primary power source cooling unit to a transient event threshold temperature;
• in response to determining that the primary cooling fluid temperature is not greater than the transient event threshold temperature, setting a primary cooling fan to a first primary cooling fan speed corresponding to the primary cooling fluid temperature to discharge a first airflow onto the primary power source cooling unit, and setting a secondary cooling fan to a first secondary cooling fan speed equal to zero to prevent discharge of a second airflow onto the secondary power source cooling unit;
• and
• in response to determining that the primary cooling fluid temperature is greater than the transient event threshold temperature, setting the primary cooling fan to a second primary cooling fan speed corresponding to the transient event threshold temperature to discharge the first airflow onto the primary power source cooling unit, and setting the secondary cooling fan to a second secondary cooling fan speed corresponding to a secondary cooling fluid temperature of the primary power source cooling fluid at the secondary power source cooling unit to discharge the second airflow onto the secondary power source cooling unit.

A work machine, comprising:

• a primary fuel cell cooling unit having a primary unit inlet port and a primary unit outlet port, wherein the primary unit inlet port is fluidly connected to receive a fuel cell cooling fluid from fuel cells;
• a secondary fuel cell cooling unit having a secondary unit inlet port and a secondary unit outlet port, wherein the secondary unit inlet port is fluidly connected to the primary unit outlet port to receive the fuel cell cooling fluid from the primary fuel cell cooling unit, and the secondary unit outlet port is fluidly connected to discharge the fuel cell cooling fluid to the fuel cells;
• a primary cooling fan disposed proximate the primary fuel cell cooling unit to discharge a primary airflow onto the primary fuel cell cooling unit;
• a secondary cooling fan disposed proximate the secondary fuel cell cooling unit to discharge a secondary airflow onto the secondary fuel cell cooling unit;
• a primary cooling unit temperature sensor operatively coupled to the primary fuel cell cooling unit;
• a secondary cooling unit temperature sensor operatively coupled to the secondary fuel cell cooling unit;
• and
• a work machine controller operatively connected to the primary cooling fan, the secondary cooling fan, the primary cooling unit temperature sensor and the secondary cooling unit temperature sensor, the work machine controller being programmed to:
• receive primary temperature sensor signals from the primary cooling unit temperature sensor,
• determine a primary cooling fluid temperature of the fuel cell cooling fluid at the primary fuel cell cooling unit based on the primary temperature sensor signals,
• receive secondary temperature sensor signals from the secondary cooling unit temperature sensor,
• determine a secondary cooling fluid temperature of the fuel cell cooling fluid at the secondary fuel cell cooling unit based on the secondary temperature sensor signals,
• compare the primary cooling fluid temperature to a transient event threshold temperature;
• in response to determining that the primary cooling fluid temperature is not greater than the transient event threshold temperature, transmit primary fan control signals to the primary cooling fan to set the primary cooling fan to a first primary cooling fan speed corresponding to the primary cooling fluid temperature to discharge the primary airflow onto the primary fuel cell cooling unit, and transmit secondary fan control signals to the secondary cooling fan to set the secondary cooling fan to a first secondary cooling fan speed equal to zero to prevent discharge of the secondary airflow onto the secondary fuel cell cooling unit;
• and
• in response to determining that the primary cooling fluid temperature is greater than the transient event threshold temperature, transmit the primary fan control signals to the primary cooling fan to set the primary cooling fan to a second primary cooling fan speed corresponding to the transient event threshold temperature to discharge the primary airflow onto the primary fuel cell cooling unit, and transmit the secondary fan control signals to the secondary cooling fan to set the secondary cooling fan to a second secondary cooling fan speed corresponding to the secondary cooling fluid temperature to discharge the secondary airflow onto the secondary fuel cell cooling unit.