Computer fan control

Abstract: A method for comprehensive integrated control of an internal combustion engine, such as a compression-ignition engine, utilizing an electronic control module (20) is disclosed. The control strategy integrates various functions of engine control including an acceleration balance test for the engine cylinders, a fuel economy vehicle speed limit adder, a fuelling limit for high altitude vehicle operation, throttle logic, a data-hub for operation trending and vehicle component lifting analyses, a gear ratio torque limit, an air temperature based torque limit, enhanced cooling fan control, and a idle shutdown strategy based on ambient air temperature.

Abstract: A method for comprehensive integrated control of a compression-ignition internal combustion engine having integral fuel pump-injectors utilizing an electronic control unit (20) is disclosed. The control strategy integrates various functions of engine control including fuel delivery (34), cooling fan control (38), engine speed governing and overspeed protection, engine braking, torque control, and vehicle speed diagnostics and control. Cooling fan control (38) is integrated with vehicle speed diagnostics and control as well as fuel delivery (34) to provide an integrated cruise control function which incorporates engine braking. The method also includes improved control over the various engine speed governors while improving idle quality by balancing the power delivered by each of the engine cylinders when at idle. The integrated torque control employs functions to reduce NOx emissions and noise utilizing adaptive fuel delivery timing and a split injection strategy.

Abstract: A fan speed control system (200) for an electronic equipment enclosure comprises means for determining temperature (201, 202, 203, 210, 211) at a plurality of locations within the enclosure, means for determining operating parameters (201, 202, 203, 212) for the fan control system, means for setting operating speed (201) of at least one cooling fan, and means for exchanging information signals (205, 217, 218) relating to fan speed control system operation with an external controller. A method is also provided for controlling fan speed for an electronic equipment enclosure comprising the steps of determining temperature at a plurality of locations within the enclosure, determining operating parameters for the fan control system, setting operating speed of at least one cooling fan, and exchanging information signals relating to fan speed control system operation with an external controller.

Abstract: Electronically commutated motor and control arrangements particularly adapted for use with refrigeration systems and methods of operating refrigeration systems are disclosed. In one form, a fan control means is provided for responding to temperature of a compartment being cooled by a refrigeration system; comparing the compartment temperature with a desired temperature; and varying the speed of an evaporator fan, thereby varying the movement of refrigerated air across an evaporator and into the compartment. A regulating circuit is provided for maintaining the evaporator at a reference temperature by controlling the output signal of an alternator which supplies energization power to winding stages of a brushless DC motor. By varying the energization level of the winding stages, a compressor, which is coupled to the motor, is caused to vary the flow rate of refrigerant through the evaporator so as to maintain the evaporator at the reference temperature. The regulating circuit includes means for responding to a signal from the fan control means, which is indicative of the fan speed and relative compartment cooling demand, for changing the reference temperature for the evaporator thereby to cause variance in the temperature of air moved about the evaporator by the fan for controlling temperature within the compartment. The regulating circuit also includes: means for limiting and controlling motor winding current to a maximum value; means for limiting motor speed to a predetermined low value; means for limiting and controlling motor speed to a maximum high value; means for assuring a minimum energization level for the motor winding stages; means for limiting the energization level of the winding stages to a maximum voltage value; and means for inhibiting motor operation if the evaporator temperature is less than a predetermined low temperature value.