In this article, a fast and parameter-intensive loss minimization algorithm (LMA) is proposed for the surface-mounted permanent magnet synchronous machine (PMSM). The algorithm utilizes ripple ...correlation control to steer the operating point toward the optimal solution by evaluating the correlation between the injected ripple on the control variable and its effect on the input power. Unlike model-based LMAs, this method does not rely on the motor loss model, its parameters, or precomputed information. Instead, it employs a high-speed search-based procedure to minimize the input power directly. The theoretical analysis includes a design procedure and a method for determining the upper bound of the injected ripple frequency based on the principles underlying loss minimization of PMSMs. Since the d-axis current does not contribute to torque production in surface-mounted PMSMs, the artificial perturbation introduced by the algorithm does not result in undesirable torque ripple. The analysis is supported by simulations and experimental tests. The results demonstrate that the proposed algorithm enables the system to converge to the optimum point within around 1.5 s, making it suitable for high-dynamic applications.
Effective condition monitoring of motors is crucial in diverse electric powertrain systems, including applications in electric transportation and nuclear power plants. Vibration analysis, a key ...component of motor condition testing, aids in identifying equipment failures, assessing operational status, and guiding preventive maintenance. However, achieving high evaluation accuracy while minimizing the number of vibration sensors to reduce operational and maintenance costs poses a significant challenge. This article introduces a novel approach for vibration testing using a spatial-spectral-based inductive graph neural network. The proposed algorithm focuses on mining vibration sensor-based clusters to reveal spatial connectivity and spectral correlation patterns. It efficiently aggregates and extracts features from sensor graph signals near the target location, subsequently reconstructing vibration signals using convolutional networks to create a virtual sensor. To validate the effectiveness of the proposed method, experimental verification was conducted on a 21 kW interior permanent magnet synchronous motor testing rig equipped with Brüel and Kjær's vibration sensing equipment. The results demonstrate the algorithm's ability to enhance evaluation accuracy and reliability. This innovative approach not only contributes to the field of motor condition monitoring but also addresses the challenge of minimizing the number of vibration sensors, thereby reducing manual operation and maintenance costs associated with sensor networks.
Inaccurate motor parameters can lead to deterioration of the control system performance of permanent magnet synchronous motor (PMSM). In order to mitigate the adverse control outcomes caused by ...inaccurate motor parameters and the impact of these parameters on model predictive current control, in this article, a predictive current error compensation-based strong robust model predictive control (PCEC-MPC) for PMSM drive systems is proposed. This method does not require accurate motor parameters. Instead, perturbation terms of inductance, resistance, and flux-linkage are designed to replace the motor parameters, and then the expression equations of the perturbation terms are obtained by constructing the predictive current error compensation controller. Besides, a balancing factor is introduced to equalize the impact of both current and perturbation terms on the predictive model. Finally, the feasibility of the proposed method is verified experimentally.
The impact of the static eccentricity fault on electrical machines has been extensively explored in the literature. Various contributions have provided valuable models, such as the modified winding ...function approach (MWFA), which effectively characterizes the inductance behavior of an eccentric permanent magnet synchronous machine (PMSM). Recently, a comprehensive solution for the MWFA formula has been published, presenting an analytical expression for the machine's phase inductances and their harmonic components. Building on this achievement, the presented study investigates how static eccentricity influences the measurements obtained from a sensorless technique reliant on zero-sequence voltage, such as direct flux control (DFC). DFC offers highly consistent and precise inductance-dependent measurements, rendering it a viable option for designing fault detection techniques. In this study, a mathematical model is formulated to analytically describe DFC measurements for an eccentric machine in order to investigate its viability for eccentricity detection. Subsequently, experimental results are provided and analyzed.
This paper proposes a novel four-leg inverter topology to drive the dual three-phase permanent magnet synchronous motor (DTP-PMSM) with 180° phase-shifting. Without access to the midpoint of DC bus ...capacitors, the proposed four-leg inverter can not only drive the DTP-PMSM with the same torque capability as the conventional six-leg inverter, but also avoid the voltage fluctuations of the capacitors in the conventional four-leg inverter. Then, two kinds of pulse width modulation (PWM) methods are given and compared for the proposed topology. The first one is the direct extension of the space vector modulation (SVM) of the four-switch inverter, denoted as SVM1, and the second one is to construct space voltage vectors utilizing almost all the switching states of the four-leg inverter, denoted as SVM2. Experimental results verify the feasibility of the proposed four-leg inverter topology and demonstrate the better harmonic performance of SVM2 compared to SVM1.
This study proposes an advanced current and position sensor fault diagnosis mechanism for permanent magnet synchronous motor (PMSM) applications. Machine nonlinear dynamics as well as parameter and ...load uncertainties are addressed. The features of the results of this study are summarized as follows: 1) a proportional-type full-state observer is combined with a disturbance observer to deal with the model uncertainties, 2) a partial optimal process is introduced for determining the observer gain, 3) the concept of normalized residuals is introduced for fault diagnosis criteria, and 4) a closed-loop analysis of the convergence, performance recovery, and offset-free guarantee is provided. The performance recovery property makes the proposed algorithm robust to parameter uncertainties and load variations, and sensitive only to sensor faults. In addition, the location and type of sensor faults can be identified by the fault diagnosis criteria using the normalized residuals. The performance of the sensor fault diagnosis algorithm was experimentally verified under several credible scenarios using a 7.5-kW PMSM.
In order to enhance prediction precision and tracking performance of current controllers for permanent magnet synchronous motor (PMSM) drives subject to control delay and disturbances, a ...switching-active-disturbance-rejection-based deadbeatpredictive current control (SADR-DPCC) strategy of the PMSM is presented in the paper. Firstly, traditional DPCC strategy is introduced based on the dynamic model of the PMSM and parameter sensitivity of the DPCC is analyzed. Then an active-disturbance-rejection-based DPCC (ADR-DPCC) strategy is presented to alleviate the influence of disturbances on the DPCC controller. However, the ADR-DPCC only with the linear extended state observer (LESO) is incompetent in the applications with high requirement of control accuracy and robustness. Therefore, the SADR-DPCC strategy of the PMSM is proposed to integrate the advantages of the LESO and nonlinear extended state observer (NLESO) with a hysteretic switching strategy. Moreover, the stability analysis and parameter setting of the NLESO are elaborated, which are simplified by the switching strategy of the SADR-DPCC. Finally, the effectiveness and superiority of the SADR-DPCC are validated experimentally.
Current harmonics will deteriorate the performance of permanent magnet synchronous motor (PMSM) drives, and active disturbance rejection control (ADRC) is a promising method to reduce the harmonics. ...However, determined by the observation and compensation level of extended state observer (ESO), the harmonic suppression ability of the traditional ADRC is limited. To significantly decrease low-frequency current harmonics, this article proposes a novel active disturbance rejection repetitive control scheme used for current loops, in which two improvements for the ESO are presented. One is the introduction of a low-pass filter (LPF) instead of the conventional integrator, and that can enhance the disturbance observation capability. Based on this new LPF-ESO, the other is the increase of a repetitive controller in parallel with the disturbance loop, which can further estimate the periodic disturbances and thus improve the compensation performance at specific periodic frequencies. The parameter design, stability, anti-disturbance ability, tracking performance and robustness of the proposed ADRC current loop are analyzed. Compared with the traditional ADRC, the proposed scheme can obviously reduce the current harmonics, moreover, fast dynamic response and strong robustness can be achieved. The simulation and experimental results about a 1.1-KW PMSM are provided to verify the effectiveness of the proposed scheme.
In this article, switching strategies for dc-link current and voltage ripple reduction have been studied. The considered topology is a neutral-point clamped three-level (NPC-3L) inverter feeding a ...dual three-phase permanent-magnet synchronous motor (PMSM). The mechanisms of dc-link current and voltage ripple generation in an NPC-3L inverter-fed PMSM drive are analyzed in detail. Then, a two-step collaborative switching strategy is proposed, where the optimum switching sequences, including opposite small vectors, are applied in the two inverters collaboratively. Furthermore, the switching vectors of two inverters are rearranged in the sequence of their corresponding dc-link capacitor currents so that the overlapping of their peaks is avoided. Consequently, both the voltage ripple and current ripple in the dc-link capacitors are mitigated with the proposed two-step collaborative switching strategy. For the midpoint voltage of the NPC-3L inverter, the amplitude of fluctuation is reduced under low modulation index operation, while the high-frequency harmonic components are mitigated under high modulation index operation. The experimental results are given to verify the validity of the theoretical analysis and the proposed switching strategy.
