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This study presents the design of a 2‐pole high‐speed BLDC motor for kitchen blenders and its control method with the aim to reduce the speed ripple that decreases the grinding performance in the high‐speed region. In blender machines, the high pulsating load caused by the blending materials such as ice cubes acting on the grinding blade, create significant speed ripple in the constant power region. Because current and torque are limited to protect the drive, the actual motor torque cannot overcome the pulsated load if the speed reference is maintained. Therefore, the speed fluctuates, and the grinding performance is lowered. In the proposed variable speed reference control scheme, the speed command is continuously modified to overcome the maximum pulsating torque requirement which results in lower speed ripple. To achieve this, if the load torque suddenly increases, the current value is then set based on the maximum load and speed reference value is temporarily lowered. If then the load torque becomes lower than the actual torque, the previously set speed reference value is reused. The design result and grinding performance of the proposed control method are verified by simulations and experiments. Hard white beans are used for actual performance testing. [ABSTRACT FROM AUTHOR]

Based on the back electromotive force (back‐EMF) detection, a novel rotor position estimation strategy with adjustable turn on/off angle is proposed for the high‐speed hybrid switched reluctance motor (SRM). The minimum back‐EMF position is captured in every electrical cycle for rotor position estimation. The current comparator is employed to send out a turn‐off signal for phase winding when the maximum inductance position is detected in the first electrical cycle. By providing sufficient current rise time to the phase winding, the proposed sensorless control system enables the motor to run in high‐speed application. Besides the straightforward estimation principle, the proposed strategy has the implemental feasibility by eliminating extensive calculations and complicated look‐up tables. The experimental results of a prototype are demonstrated to verify the proposed sensorless control system. [ABSTRACT FROM AUTHOR]

Selection of electrical machine is a key issue in electrical and hybrid electrical vehicles (HEVs and EVs). As far as HEVs and EVs are concerned, mechanical ruggedness of electrical machine is of utmost importance. For these reasons, the application of switched reluctance (SR) machine in EVs and HEVs is a viable option. In this study, an SR generator (SRG) has been utilised to work as a battery charger in EVs. The current ripple of the SRG is the greatest issue when it works as a battery charger. Therefore, a power converter and a smart search control (SSC) approach are proposed in this study to decrease the current ripple when the output power has a maximum quantity. During the system operation, the SSC method determines the value of excitation angle, turn‐on and turn‐off angles for each phase of SRG. The simulation and experimental results demonstrate the eligibility of the SSC system and power converter to obtain the acceptable charging current in maximum generated power during battery charging. [ABSTRACT FROM AUTHOR]