A deadbeat predictive current control (DPCC) method based on extended state observer (ESO) is proposed to improve the control performance of dual three-phase permanent magnet synchronous motors (DTP-PMSMs) under parameter mismatch. A variable gain coefficient related to the exponential function of tracking error is proposed to enhance the observer's convergence and robustness under complex conditions. Furthermore, the prediction delay problem of DPCC model under digital hardware is studied, and an improved prediction method is proposed to compensate for the delay time, reducing the response time and overshoot of the system under the DPCC algorithm. The proposed ESO is combined with the improved prediction model, and DPCC with two-sample delays is employed to reduce the prediction current error and enhance the control performance of the algorithm in practical applications. The stability of the system is demonstrated using the Hurwitz Criterion. Experimental results validate the superiority and feasibility of the proposed algorithm for the control and drive of DTP-PMSMs.

Churning power losses are an important portion of the transmission load independent power losses, especially in high-speed condition and dip-lubricated gearboxes with high immersion depth. Generally, it is difficult to calculate the churning power losses due to the parameters of stirring oil and many other operating conditions. In this paper, a method is proposed to determine the influence factors on the churning power losses of gearboxes. Firstly, based on the moving particle semi-implicit (MPS) method, a numerical model of single-stage gears stirring oil is established. Then the accuracy of the established model is validated by an experiment. Finally, the orthogonal simulation analysis is carried out to analyze the influence of gear rotation speed, tooth width, helix angle, immersion depth and oil temperature on the churning power losses.

This paper focuses on the electromagnetic vibration noise source of fractional-slot concentrated-windings (FSCWs) interior permanent magnet synchronous machines (PMSMs) and its optimal design for vibration noise reduction. First, the analytical model of the radial and tangential force waves of the interior PMSM is constructed, and the harmonic characteristics of the electromagnetic force waves under the action of the stator slotting effect and the rotor saliency effect are obtained. Second, an electromagnetic field finite element simulation model of a 36-slot/24-pole PMSM is established, and the harmonic sources of the main excitation forces are explored in combination with the analytical method. Then, the simulation analysis method of vibration noise with separately loaded radial and tangential concentrated forces is proposed to explore the contribution of different force wave components to the vibration noise. Finally, the main excitation force of the prototype is weakened by using an auxiliary groove, and the auxiliary groove parameters are optimized by sensitivity analysis and multi-objective genetic algorithm, and the effectiveness of the optimization method is verified by simulation and experiment. This study can provide a reference for the low-vibration and low-noise design of the same type of machine.

Due to the external noise disturbance, measurement error will be inevitably occurred in the measurement stage of model predictive torque control (MPTC), resulting in the wrong selection of the optimal voltage space vectors (VSVs) in the optimization stage of MPTC, and even affect the stability of the whole control system. This article proposed an improved MPTC scheme for interior PMSM (IPMSM) drives. In the proposed MPTC, a Kalman anti-disturbance observer (KADO) based on the Kalman filter (KF) is designed for estimating the mechanical angular velocity, rotor position and load torque accurately, which can suppress the poor performance of the system caused by the external disturbances. Moreover, to alleviate the calculated complexity, a switching table composed of active prediction vectors is set to predict the appropriate VSVs. The traditional MPTC with disturbances and without disturbances are compared with the proposed MPTC in the simulations and experiences, which proves the effectiveness of the proposed MPTC in suppressing white noise disturbance.

Dual-clutch transmissions (DCTs) are very sensitive to torsional vibration and easily produce rattle noise if a single-mass flywheel (SMF) with a conventional torsional damper or a dual-mass flywheel (DMFW) is used in the vehicle. Only a DMFW combined with a centrifugal pendulum vibration absorber (CPVA) can eliminate rattle problem; however, this solution is expensive. Alternatively, a SMF with a CPVA is proposed to eliminate the DCT rattle issue, which could be a feasible and cost-effective solution free of side effects introduced by DMFWs. The vibration absorption principle of different types of pendulums and the rotor dynamic model are investigated to study the feasibility of a SMF with CPVA in a DCT vehicle. A seven-degree-of-freedom nonlinear lumped torsional vibration model is proposed to evaluate the torsional vibration attenuation performance of different configurations of torsional dampers and CPVAs. As per the model calculation results, the bifilar pendulum features the best attenuation performance compared with the circular and cycloid pendulums. The effect of pendulum parameters on attenuation is studied, and the optimized values are obtained. The SMF and optimized bifilar CPVA combination can satisfy the no-rattle requirements in vehicle relative to the DCT in-vehicle no-rattle threshold. A vehicle assessment on roads using physical pendulum prototypes indicates that the SMF with CPVA can be used as an alternative, cost-effective solution for DCTs, instead of the expensive DMFW with CPVA solution.

Addressing the thermal management challenges associated with the stator and rotor system of yokeless and segmented armature (YASA) motors, this article proposes an enhanced cooling strategy for the stator and rotor. Taking a dual-rotor single-stator YASA motor as the research subject, the volume of fluid (VOF) model is employed to evaluate the cooling performance of the existing advanced oil cooling technique. Subsequently, the stator bracket is perforated to enable cooling oil to flow into the air gap area for direct heat exchange with the stator and rotor system. By investigating the impact of the number of holes on both the motor’s cooling performance and oil friction loss, the optimal hole configuration is determined to be a direct cooling solution with hole of $1\times 1.5$ mm. Compared with the existing cooling scheme, the maximum temperatures of windings, stators, permanent magnets, and rotors under rated conditions are reduced by 29.14%, 28.53%, 51.67%, and 50.21%, respectively. Through the comparison of temperature rise experiments, the accuracy of thermal simulation modeling and the efficiency of the cooling system are further verified, which provides a new method for the design of efficient cooling system of YASA motor.