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To improve the torque control accuracy of an open‐winding permanent magnet synchronous motor with common DC bus, this paper studies a complex vector proportional–integral (CVPI) controller with the help of a proportional–integral (PI) controller to solve the problem of torque ripple caused by the current harmonics caused by the back electromotive force of the motor and the nonlinearity of the inverter. The controller has a higher gain at the center frequency and can realize the tracking of the alternating current (AC) quantity without static error. Therefore, it is used for the tracking control of current harmonics. According to the different characteristics of the dq0‐axis, complex j is realized by orthogonal characteristics and all‐pass filter in the dq‐axis and 0‐axis, respectively. At the same time, with the help of Ansys, Simplorer, and Matlab/Simulink tools, the co‐simulation platform for an open‐winding motor is established, and the motor parameters are optimized. The simulation and experimental results show that the control strategy based on CVPI has stronger harmonic suppression ability, smaller torque ripple, and better dynamic performance than proportional‐resonance (PR) control. [ABSTRACT FROM AUTHOR]

Phase engineering is a central subject in materials research. The recent research interest in the phase transition behavior of atomically thin 2D materials reveals the important role of their surface chemistry. In this study, we investigated the phase transformation of ultrathin TiO2(B) nanosheets to anatase under different conditions. We found that the convenient transformation in water under ambient conditions is driven by the hydrolysis of surface 1,2-ethylenedioxy groups and departure of ethylene glycol. A transformation pathway through the formation of protonic titanate is proposed. The ultrathin structure and the metastable nature of the precursor facilitate the phase conversion to anatase. Our finding offers a new insight into the mechanism of TiO2(B) phase transition from the viewpoint of surface chemistry and may contribute to the potential application of ultrathin TiO2(B) nanosheets in aqueous environments. [ABSTRACT FROM AUTHOR]

Phase engineering is a central subject in materials research. The recent research interest in the phase transition behavior of atomically thin 2D materials reveals the important role of their surface chemistry. In this study, we investigated the phase transformation of ultrathin TiO 2 (B) nanosheets to anatase under different conditions. We found that the convenient transformation in water under ambient conditions is driven by the hydrolysis of surface 1,2-ethylenedioxy groups and departure of ethylene glycol. A transformation pathway through the formation of protonic titanate is proposed. The ultrathin structure and the metastable nature of the precursor facilitate the phase conversion to anatase. Our finding offers a new insight into the mechanism of TiO 2 (B) phase transition from the viewpoint of surface chemistry and may contribute to the potential application of ultrathin TiO 2 (B) nanosheets in aqueous environments.