To control the high‐frequency acoustic noise of the permanent magnet synchronous machine (PMSM) with the space vector pulse‐width modulation (SVPWM), an investigation into the mechanism of the sideband vibro‐acoustics is presented in this study. Especially, the relationship is developed between the sideband electromagnetic components and the mechanical vibro‐acoustics, which paves the fundamentals to reduce the noise at the sources. Firstly, the analytical derivations of the sideband voltage and current harmonics are expressed, while the magnetic components of permanent magnet and armature reaction are also discussed in different carrier frequency domains. Secondly, the corresponding radial electromagnetic force analysis is established to acquire the pattern of the vibro‐acoustic. Finally, the proposed multi‐physics models are reconstructed by coupling spatial and temporal features, where the amplitudes are also calculated. A 12‐slot10‐pole prototype PMSM is considered as a case study to testify the accuracy of the proposed method, where the corresponding electromagnetic components are calculated and measured under different conditions, together with the vibration and acoustics. This investigation may provide a new route for the acoustics prediction and the precise optimisation of PMSM.

This paper presents a comprehensive investigation into the sideband vibro-acoustics with continuous and discontinuous pulse-width modulation (PWM) strategies in permanent magnet synchronous motor (PMSM). The primary motivation for the evaluation reveals the frequency distributions of the sideband components and the magnitudes suppression with the space vector PWM (SVPWM) and the discontinuous PWM (DPWM). The principle and implementation of the conventional SVPWM and six basic DPWM modes are firstly presented. The sideband harmonic components are provided by the analytical derivations, in which the frequency distributions are established by coupling the temporal features between the current harmonics and radial electromagnetic force. To evaluate and compare the sideband current harmonics and vibro-acoustic responses among the PWM schemes, the experimental tests are presented in a study case of 12 /10 PMSM. Significant deterioration is observed in each of the basic DPWMs compared to that in SVPWM. Developed with periodic dithering modulation, notable sideband harmonics suppression and vibro-acoustic improvements in DPWM schemes are observed. This work is expected to provide guidance for a hybrid modulation strategy in electric vehicles.

This paper presents an investigation into sideband vibro-acoustics suppression of the permanent magnet synchronous motor (PMSM), associated with several periodic signal-based dithering modulations. Mathematical derivations of four typical periodic signal-based schemes are deduced with the power spectral density (PSD) method. The individual modulation parameters, such as bandwidth and modulation ratio, are determined the values to minimize the sideband vibro-acoustics. The frequency distributions of the sideband components are discussed by the analytical derivations. The relationship between the electromagnetic components and mechanical responses is reconstructed by coupling with temporal features. For verification, the experimental tests with a prototype PMSM are introduced under different operational conditions. According to the results and figures, both magnitude suppression and frequency distribution are accurately correlated with sideband harmonic components as well as vibro-acoustic responses. This investigation thus clearly holds promise for the evaluation and optimization in powertrain used by electric vehicles.

In the research on electric vehicle transmission vibration characteristics, the dynamic model involving a multistage gear system is still rare, especially the influences of driving motor excitation and load excitation which are not considered, and which makes the gear system research deviate from the actual situation. In addition, the changing processes of variables are usually simplified or neglected in the study of gear systems, which is not conducive in revealing the mechanism of gear dynamic behavior. In this paper, an improved dynamic model of a motor-gear system is established. The influences of driving motor excitation and load excitation are included, and the changing processes of tangential, axial, and torsional vibration variables of driving gear and driven gear are obtained using the state space method. Furthermore, the transmission housing vibration responses are investigated. By comparing the simulation results with the measurement data, the improved dynamic model, as well as the state space solution method, are verified as reliable and universal. On this basis, the influence of motor excitation on the state change of the gear system is discussed, which provides a theoretical approach for further study of motor drive gear systems.

In the permanent magnet synchronous motor (PMSM) drive system, the unwilling and ear-piercing vibro-acoustics caused by high-frequency sideband harmonics becomes unacceptable in electric vehicle applications. In this paper, a modified space vector pulse width modulation (SVPWM) technique implemented with a hybrid carrier frequency modulation (HCFM) is provided to reduce the sideband current harmonic components and vibro-acoustic responses. The principle and implementation of the proposed HCFM technique are firstly presented in which the fixed carrier frequency is improved with the sawtooth and random signal-based coupling modulation based on the rotor position. The analytical derivations with the power spectral density method are also proposed. For verification, the experiment tests are conducted on a prototype 12/10 PMSM and microcontroller unit. The effectiveness of the HCFM technique can hence be confirmed considering the sideband vibro-acoustics reduction operated more effectively than that in a conventional random PWM. The proposed approach may provide a new route in noise-cancelling and electromagnetic compatibility for the electric drive powertrain.

This article proposes a new adaptive gain, full-order terminal sliding mode control algorithm for the speed regulation of a surface-mounted permanent magnet synchronous motor (SPMSM) control system. To deal with the mismatched uncertainties in the double-loop nonlinear system of the SPMSMs, a virtual control technique is constructed with the full-order terminal sliding mode control to ensure that the tracking error trajectory can converge to equilibrium in finite time. Owing to the integral control law, the output signals of the controllers are smoothed, with the chattering phenomenon attenuated and the gain-margin overestimation avoided. Comprehensive simulation and experimental results have been carried out to demonstrate the superiority of the proposed method in improving tracking accuracy, rapidness, and robustness to the matched and mismatched uncertainties.