Electric Machine Three-Level Power Control for Partial-Load Efficiency

The patent segments the torque output into at least three distinct levels (first torque level, second torque level, and third torque level) instead of using only two levels. This segmentation allows for more granular control of the pulsed torque application, enabling the system to achieve the desired average torque while reducing acoustic abnormalities through smoother transitions and more distributed torque variations.

The patent changes the parameter of torque levels from two levels to at least three levels. By introducing an additional torque level (the third torque level between the first and second torque levels), the system modifies the torque profile to reduce acoustic abnormalities while maintaining energy conversion efficiency improvements. The control unit adjusts the duration and magnitude of each torque level to optimize both efficiency and acoustic performance.

The patent implements periodic action by alternating between at least three different torque levels over time. The control unit switches between the first torque level, second torque level, and third torque level in a periodic manner, creating a pulsed torque profile that improves energy conversion efficiency by operating the electrical machine at higher torque levels more frequently, while the periodic nature of the switching helps manage acoustic abnormalities.

The patent introduces dynamics by making the torque output variable rather than static. The control unit dynamically adjusts the torque level between at least three different values based on operating conditions, allowing the system to adapt to changing load requirements while maintaining high energy conversion efficiency. This dynamic torque adjustment enables the system to operate in high-efficiency regions more often compared to continuous single-level operation.