Abstract: A method of starting and/or driving a fan assembly, the fan assembly comprising a BLDC motor having one or more coils, and a bearing comprising a lubricant. The method comprises performing a special action for intentionally heating up the one or more coils and thereby indirectly heating up the lubricant. The method may comprise measuring a temperature of the bearing, or measuring a value related to said temperature, and performing the special action only if said temperature is below a certain threshold temperature. Performing the special action comprises setting an off-time to a first predefined value and setting an on-time to a second predefined value, the first and second predefined value having a first ratio. Starting the motor comprises setting the off-time to a third value and setting the on-time to a fourth predefined value, the third and fourth predefined value having a second ratio larger than the first ratio.

Abstract: A method of starting and/or driving a fan assembly, the fan assembly comprising a BLDC motor having one or more coils, and a bearing comprising a lubricant. The method comprises performing a special action for intentionally heating up the one or more coils and thereby indirectly heating up the lubricant. The method may comprise measuring a temperature of the bearing, or measuring a value related to said temperature, and performing the special action only if said temperature is below a certain threshold temperature. Performing the special action comprises setting an off-time to a first predefined value and setting an on-time to a second predefined value, the first and second predefined value having a first ratio. Starting the motor comprises setting the off-time to a third value and setting the on-time to a fourth predefined value, the third and fourth predefined value having a second ratio larger than the first ratio.