Fan control method, apparatus, and sytem

A fan control apparatus, comprising:

• a receiving unit, configured to receive a first fan regulation and control signal sent by a system control module, wherein the first fan regulation and control signal is used to control a rotation direction of a fan, and the system control module is configured to deliver a control signal according to an instruction of a host computer to control operating of the fan;
• a converting unit, configured to convert the first fan regulation and control signal received by the receiving unit to a forward-rotating control signal, a counter-rotating control signal, or a rotation direction switchover control signal according to a duty cycle range of the first fan regulation and control signal and a current rotation direction of the fan;
• and
• a sending unit, configured to send a control signal obtained by the converting unit to a fan driving module, so that the fan driving module drives, according to the control signal obtained by the converting unit, the fan to operate.

A fan control system, comprising:

• a host computer, a system management apparatus, a fan interface connection apparatus, and a fan, wherein:
• the host computer is configured to send a rotation direction control command to the system management apparatus;
• the system management apparatus is configured to send a first fan control signal to the fan by using the fan interface connection apparatus and according to the rotation direction control command;
• the fan interface connection apparatus is configured to connect the system management apparatus to the fan, and comprises a power supply positive interface, a power supply negative interface, a fan control signal interface, and a fan rotational speed frequency feedback signal interface, wherein one side of the power supply positive interface and one side of the power supply negative interface are respectively connected to a positive electrode and a negative electrode of a power supply in the system management apparatus by using a power supply bus, another side of the power supply positive interface and another side of the power supply negative interface are respectively connected to a positive electrode and a negative electrode of the fan by using a power supply bus, one side of the fan control signal interface and one side of the fan rotational speed frequency feedback signal interface are connected to a signal control interface in the system management apparatus by using a control bus, and another side of the fan control signal interface and another side of the fan rotational speed frequency feedback signal interface are connected to the fan by using a control bus;
• and
• the fan is a four-wire system fan and is configured to receive the first fan regulation and control signal sent by the system management apparatus, convert the first fan regulation and control signal to a forward-rotating control signal, a counter-rotating control signal, or a rotation direction switchover control signal according to a duty cycle range of the first fan regulation and control signal and a current rotation direction of the fan, and regulate the rotation direction of the fan according to a control signal obtained by the conversion.