7 research outputs found
Investigating electrical drive performance employing model predictive control and active disturbance rejection control algorithms
Many issues can degrade the electrical drive performance such as cross-coupling, time delay, external disturbances, and parameter variation. The Synchronous Reference Frame (SRF) PI Current Controller (CC) is the most popular control scheme for the motor drive current control due to its simplicity. However, the PI controller does not have an optimal dynamic response due to the reasonably low transient response of the integral parts. Furthermore, the tuning of the PI controller depends heavily on the machine’s parameters. Recently, alternative control schemes such as Model Predictive Control (MPC) and Active Disturbance Rejection Control (ADRC) are studied due to their dynamic performance and disturbance rejection capability, respectively. This paper presents a comparative study between the conventional PI, ADRC, and MPC control schemes applied for Permanent Magnet Synchronous Motor (PMSM) taking into consideration the operational issues of electrical drives
Evaluation of strand-to-strand capacitance and dissipation factor in thermally aged enamelled coils for low-voltage electrical machines
© The Institution of Engineering and Technology 2019. The dissipation factor (i.e. tanδ) and insulation capacitance (IC) measurements are conventional monitoring methods for assessing the aging level of insulation systems. These quantities provide an invaluable indication of the dielectric losses within the insulating materials. However, how these values are affected by the aging processes due to thermal stresses have until today never been investigated fully. Thus, this study exhibits the influence of thermal aging on tanδ and IC of windings for electrical machines (EMs). The work is performed for class 200, round enamelled magnet wire specimens. The study aims at improving the design process of EMs for short duty cycle applications; hence, its outcome might be included at the design stage for enhancing reliability and lifetime. Random wound coils are chosen in the performed study, because they are the most common winding arrangement for low-voltage EMs, which are employed in a wide range of applications (e.g. from home appliances to aerospace motors). Based on the collected data, considerations regarding the impact of relative humidity on both the dissipation factor and IC are presented. Finally, the correlation between the partial discharge inception voltage and the diagnostic measurements is experimentally verified
Experimental Investigation of Decoupled Discontinuous PWM Strategies in Open-End Winding Induction Motor Supplied by a Common DC-link
© 2023 IEEE. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1109/JESTPE.2023.3258799Currently, open-end winding induction motors fed by a dual inverter (OEWIM-DI) present an innovative approach to enhance the performance of modern electric drive systems, such as electrical vehicles and electric aircraft applications. However, the DI topology requires a proper switching control strategy to enable the OEWIM drive to fully achieve its performance. This work aims to investigate experimentally the impact of different decoupled discontinuous pulsewidth modulation (DDPWM) control strategies on the performance of the OEWIM-DI supplied by a common dc-link. The criteria performances adopted in this study are: 1) the total harmonic distortion (THD) of the current and voltage; 2) the zero sequence voltage (ZSV); 3) the common mode voltage (CMV); and 4) the DI losses. The various DDPWM control schemes for the 1.5-kW OEWIM-DI motor drive are implemented on a dSPACE 1104 board, and the results are compared with the popular and widely used space-vector PWM (SVPWM) strategy. From the results, it can be concluded that the optimized DDPWM technique gives the best performance. This technique has reduced the CMV by one level and reduces the losses by 50% while having the same THD and ZSV obtained with the SVPWM technique.Peer reviewe
Moving Toward a Reliability-Oriented Design Approach of Low-Voltage Electrical Machines by Including Insulation Thermal Aging Considerations
© 2020 IEEE. Electrical machines (EMs) are required to consistently perform their intended mission over a specified timeframe. The move toward transportation electrification made the EMs' reliability an even stringent and predominant requirement, since a failure might cause severe economic losses, as well as endanger human lives. Traditionally, the design procedure of motors conceived for safety-critical applications mainly relies on over-engineering approaches. However, a paradigm shift is recently taking place and physics of failure approaches/methodologies are employed to meet the reliability figures, while delivering an optimal design. This article proposes and outlines a reliability-oriented design for low-voltage EMs. Thermal accelerated aging tests are preliminarily carried out on custom-built specimens. Once the aging trend of the turn-to-turn insulation system is assessed, the thermal endurance graph at several percentile values is determined and lifetime models are developed, for both constant and variable temperature operations. Finally, these models are used to predict the turn-to-turn insulation lifetime of motors meant for aerospace and automotive applications
Profiling the Eddy Current Losses Variations of High-Speed Permanent Magnet Machines in Plug-in Hybrid Electric Vehicles
High-speed permanent magnet (PM) machines have been recognized as a popular choice for plug-in hybrid electric vehicles (PHEVs). Although high-speed operation can enhance the machine power density, more rotor eddy current losses can be expected. Those losses dominantly result from the current harmonics that may vary during the vehicle driving cycles. Therefore, it is crucial to profile the eddy current losses variations, thus identifying the worst case. To achieve this objective, a new indicator, namely the frequency-weighted harmonics distortion (FWTH), is defined correlating with eddy current losses in this paper. Profiling eddy current losses variations by FWTH relieves the computational burden seen in the finite element analysis (FEA) as its derivation simply governs all the current harmonics. Various machine and converter operation conditions are covered in the study. The strong correlations between the addressed FWTH factor and the eddy current losses have been validated from the FEA, and then the experimental results on a 110krpm, 35kW PM machine served in PHEVs. The effectiveness of using FWTH to profile the eddy current losses variations during driving cycles has been proven, where the worst eddy current case has been identified for the tested machine