A fan control circuit with temperature compensation includes an on-off unit and a speed adjustment unit. When determining that a loading is greater than or equal to an adjustable start threshold according to a load signal, the on-off unit controls the fan entering a working mode. In the working mode and determining that the loading is less than a speed-adjusting threshold, the on-off unit maintains a speed value of the fan at a first fixed speed. When determining the loading is greater than or equal to the speed-adjusting threshold, the speed adjustment unit adjusts the speed value according to the loading. The speed adjustment unit generates a speed displacement according to a temperature signal to compensate the speed value.

A fan control circuit with temperature compensation includes an on-off unit and a speed adjustment unit. When determining that a loading is greater than or equal to an adjustable start threshold according to a load signal, the on-off unit controls the fan entering a working mode. In the working mode and determining that the loading is less than a speed-adjusting threshold, the on-off unit maintains a speed value of the fan at a first fixed speed. When determining the loading is greater than or equal to the speed-adjusting threshold, the speed adjustment unit adjusts the speed value according to the loading. The speed adjustment unit generates a speed displacement according to a temperature signal to compensate the speed value.

A motor control system includes a motor switching assembly comprising a power converter positioned on a converter path, a first relay positioned on the converter path upstream of the power converter, a second relay positioned on a bypass path that is in parallel with the converter path, and a solid-state switching unit positioned upstream from the converter path and the bypass path. The motor control system also includes a control system that controls operation of the motor switching assembly, with the control system programmed to operate the solid-state switching unit in one of a conducting mode, a non-conducting mode, and a ramping mode, so as to selectively control and condition power flow therethrough. The control system is also programmed to control switching of the first and second relays between open and closed positions to selectively route power along the converter path or the bypass path.

Systems and methods for fan typing and anomaly detection may provide a pulse width modulation (PWM) control signal with a predetermined threshold duty cycle to a fan, receive a tachometer signal from the fan while the PWM control signal has the threshold duty cycle, and compare the frequency of the tachometer signal (expressed in revolutions per minute) to an expected tachometer frequency for fans of a first fan type with the PWM control signal having the threshold duty cycle, according to an RPM vs. PWM curve specified for fans of the first fan type. The systems and methods may determine, based on the comparison, that the fan is of the first fan type and provide an indication that the fan is of the first fan type to a fan controller. Deviations from expected tachometer responses may indicate an anomaly, such as an actual fan failure or a predicted fan failure.

Systems and methods for fan typing and anomaly detection may provide a pulse width modulation (PWM) control signal with a predetermined threshold duty cycle to a fan, receive a tachometer signal from the fan while the PWM control signal has the threshold duty cycle, and compare the frequency of the tachometer signal (expressed in revolutions per minute) to an expected tachometer frequency for fans of a first fan type with the PWM control signal having the threshold duty cycle, according to an RPM vs. PWM curve specified for fans of the first fan type. The systems and methods may determine, based on the comparison, that the fan is of the first fan type and provide an indication that the fan is of the first fan type to a fan controller. Deviations from expected tachometer responses may indicate an anomaly, such as an actual fan failure or a predicted fan failure.

A motor control system includes a motor switching assembly comprising a power converter positioned on a converter path, a first relay positioned on the converter path upstream of the power converter, a second relay positioned on a bypass path that is in parallel with the converter path, and a solid-state switching unit positioned upstream from the converter path and the bypass path. The motor control system also includes a control system that controls operation of the motor switching assembly, with the control system programmed to operate the solid-state switching unit in one of a conducting mode, a non-conducting mode, and a ramping mode, so as to selectively control and condition power flow therethrough. The control system is also programmed to control switching of the first and second relays between open and closed positions to selectively route power along the converter path or the bypass path.