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Five-phase induction motors have the characteristics of high torque density, low torque ripple, and flexible control, making them suitable for medium- and low-voltage power supply situations. However, with the expansion of application scenarios, five-phase motors need to cope with increasingly complex operating conditions. Five-phase motors for propeller propulsion will face various complex sea conditions during actual use, and five-phase motors for electric vehicles will also face various complex road conditions and operating requirements during use. Therefore, as a propulsion motor, its speed control system must have strong robustness and anti-disturbance performance. The use of traditional PI algorithms has problems, such as poor adaptability and inability to adapt to various complex working conditions, but the use of an active disturbance rejection controller (ADRC) can effectively solve these problems. However, due to the significant coupling between the variables of induction motors and the large number of parameters in the ADRC, tuning the parameters of the ADRC is complex. Traditional empirical tuning methods can only obtain a rough range of parameter values and may have significant errors. Therefore, this paper uses ADRC based on genetic algorithm(GAADRC) to tune the parameters of the control and design an objective function based on multi-objective optimization. The parameters to be adjusted were obtained through multiple iterations. The simulation and experimental results indicate that GAADRC has lower startup overshoot, faster adjustment time, and lower load/unload speed changes compared to the empirically tuned PI controller and ADRC. Meanwhile, using a genetic algorithm for motor ADRC parameter tuning can obtain optimal control parameters while the control parameter range is completely uncertain; therefore, the method proposed in this paper has strong practical value.

The ship industry has been developed considerably in the engineering applications of deep-sea energy extraction, and the hydrodynamic performance and noise level of ships have become the focus of research for scholars and industries. In order to study the flow characteristics and acoustic characteristics of the sea suction valve, this paper conducts numerical simulation of the internal flow field and acoustic characteristics of the sea suction valve and the noise elimination trunk structure based on the numerical method of computational fluid dynamics. Through the study and analysis of different sea suction valve structures and different depths of noise elimination trunk on the flow characteristics and acoustic characteristics, it is helpful to provide guidance for engineering optimization design.

For a new type of toroidal permanent magnet linear motor(TPMLSM), this paper analyzes the thrust fluctuation in the constant acceleration operation of the motor from the Angle of the cogging force of the linear motor. For the motor whose structure has been determined and processed, the structural parameters of the motor cannot be changed, and its performance cannot be improved from the perspective of the motor body. Therefore, this paper tries to consider the influence of the cogging force on the normal operation of the motor from the perspective of control. In this paper, starting from the body structure of motor, first on the annular linear motor of the cogging force characteristics were extracted, and its expression is obtained by Fourier decomposition, then investigated considering the cogging force and does not consider the cogging force control of motor model, it can be seen that the control performance deteriorates significantly after considering cogging force of the motor, and the acceleration fluctuation increases significantly during the operation of the motor. On this basis, disturbance observation algorithm is introduced, and feedforward compensation is carried out by extracting the characteristic values of the disturbance model. The results show that the disturbance observer can suppress the thrust fluctuation caused by the motor cogging force to a large extent, and it can reduce the peak-to-peak value of the thrust fluctuation by more than 85% during the motor acceleration operation.

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