Fan Start-Up Control Using Variable Drive Signal

The patent applies dynamics by changing the driving signal from constant to variable. The control circuit dynamically adjusts the driving signal value based on the elapsed time during the open loop control stage, decreasing it from a first value to a second value. This dynamic adjustment allows the fan to start reliably with higher initial signal while reducing noise during the acceleration phase.

The patent changes the parameter of driving signal value over time. Instead of using a constant high-energy signal, the system varies the signal parameter (driving signal value) during the open loop control stage. The signal starts at a higher value for reliable startup and decreases to a lower value to minimize rotational speed overshoot and noise, while still ensuring the fan reaches the target rotational speed.

The patent implements periodic action by dividing the open loop control stage into two time periods with different driving signal values. During the first time period, a first driving signal value is used to overcome static friction. During the second time period, a lower second driving signal value is used to complete the acceleration. This periodic variation of signal values reduces overall energy consumption while maintaining reliable startup capability.

The patent changes the energy parameter of the driving signal over time. The system uses higher energy initially to ensure reliable startup, then reduces energy consumption during the acceleration phase. This parameter change allows the fan to overcome static friction with minimal energy while avoiding excessive energy consumption during the acceleration phase.