Design and Testing of a Permanent Magnet Synchronous Motor Drive System with a Novel Power Electronics Converter

Several technologies have been applied to electric vehicles (EVs) to achieve high performance in terms of mileage, speed, and efficiency. However, technological advances and customer demand are constantly revolutionizing the transportation sector. From the conventional internal combustion engine (ICE) vehicles, transportation has reached the area of hybrid electric vehicles (HEVs) and has moved towards fuel cell electric vehicles (FCEVs). Throughout this revolution, electric machines (EMs) made considerable progress. While the ICEs are phasing out because of their efficiency limitations and negative environmental impact, the EMs will remain the fundamental component of EVs. Hybrid topologies have been adopted and optimized by the industry to address several challenges related to efficiency, mileage, and ecology. However, the green transportation trend will undoubtedly lead to dominance of battery and fuel cell electric vehicles. Efficient high-speed EMs and their associated power electronics and control are therefore needed to replace and transcend ICEs. The requirement of high-speed EMs that can replace and surpass the ICE in terms of efficiency versus speed range requires associated power electronic converters that can drive the EMs through their operating envelopes. The new generation of EVs will be more demanding in terms of power, integration to the grid, efficiency, mileage; ruggedness and size reduction of power electronics interfaces and machines. The aim is to reduce the overall cost/weight of EVs and optimize energy efficiency across the entire drivetrain. This research proposes and validates a new step-by-step design method for EV drivetrain design and testing. The proposed method is based on analytically obtaining feasible drivetrain parameters from the torque-speed curve and battery nominal voltage specifications. A case study based on a 2010 Toyota Prius motor is used to validate the proposed approach for its ability to estimate feasible parameters that can be matched using finite element analysis (FEA) software. The proposed method's ability to estimate IPMSM parameters from a given SPMSM is validated iv experimentally. This method allows machines and drive specialists to work in parallel on the drivetrain component design and speed up the whole drivetrain design process. A novel integrated multipurpose power electronics interface (IMPEI) designed for PHEVs and EVs is proposed to provide a solution to the increasing need for integration and grid support of EVs. The IMPEI is analyzed, designed, prototyped, tested, and compared with several other integrated power electronics interfaces (IPEIs) and with conventional power electronics interfaces (CPEI) in this work. The proposed IMPEI and different other topologies are compared in terms of configuration, device count, cost, and efficiency, using the BMW i3 as the benchmark application. The design requirements of the IMPEI are presented and discussed, including modes of operation, switch and passive element sizing, and ratings. The results of experiments in propulsion, regenerative braking, and single-phase and three-phase V2G and G2V are presented. The experimental efficiency analysis and comparison are carried out in the propulsion, V2G, and G2V modes. The proposed analytical drivetrain design approach is used to size the drivetrain of a Renault Twizy. In this design, the IMPEI is used as a drive inverter. The potential fuel economy of the IMPEI-based Renault Twizy drivetrain is investigated based on experimental and simulation data. The IMPEI is sized and simulated in PSIM software to obtain its efficiency map throughout the operating envelope. The designed PMSM efficiency map is obtained from JMAG software. However, the mechanical system efficiency map is obtained practically throughout a drive cycle in Aachen city in Germany. A fuel economy analysis is also carried out in this work. A comparison of commonly used test benches is provided, followed by the details on the test bench used to obtain the experimental results throughout the thesis. The main components of the test bench are described. Also, a regenerative braking analysis of high-speed permanent magnet synchronous motors (PMSMs) during emergency conditions is presented. Overloading the electric machine during regenerative braking in emergency conditions using field-oriented control (FOC) is investigated

Performance Evaluation of a Cascaded H-Bridge Multi Level Inverter Fed BLDC Motor Drive in an Electric Vehicle

The automobile industry is moving fast towards Electric Vehicles (EV); however this paradigm shift is currently making its smooth transition through the phase of Hybrid Electric Vehicles. There is an ever-growing need for integration of hybrid energy sources especially for vehicular applications. Different energy sources such as batteries, ultra-capacitors, fuel cells etc. are available. Usage of these varied energy sources alone or together in different combinations in automobiles requires advanced power electronic circuits and control methodologies. An exhaustive literature survey has been carried out to study the power electronic converter, switching modulation strategy to be employed and the particular machine to be used in an EV. Adequate amount of effort has been put into designing the vehicle specifications. Owing to stronger demand for higher performance and torque response in an EV, the Permanent Magnet Synchronous Machine has been favored over the traditional Induction Machine. The aim of this thesis is to demonstrate the use of a multi level inverter fed Brush Less Direct Current (BLDC) motor in a field oriented control fashion in an EV and make it follow a given drive cycle. The switching operation and control of a multi level inverter for specific power level and desired performance characteristics is investigated. The EV has been designed from scratch taking into consideration the various factors such as mass, coefficients of aerodynamic drag and air friction, tire radius etc. The design parameters are meant to meet the requirements of a commercial car. The various advantages of a multi level inverter fed PMSM have been demonstrated and an exhaustive performance evaluation has been done. The investigation is done by testing the designed system on a standard drive cycle, New York urban driving cycle. This highly transient driving cycle is particularly used because it provides rapidly changing acceleration and deceleration curves. Furthermore, the evaluation of the system under fault conditions is also done. It is demonstrated that the system is stable and has a ride-through capability under different fault conditions. The simulations have been carried out in MATLAB and Simulink, while some preliminary studies involving switching losses of the converter were done in PSIM

A review on power electronics technologies for electric mobility

Concerns about greenhouse gas emissions are a key topic addressed by modern societies worldwide. As a contribution to mitigate such effects caused by the transportation sector, the full adoption of electric mobility is increasingly being seen as the main alternative to conventional internal combustion engine (ICE) vehicles, which is supported by positive industry indicators, despite some identified hurdles. For such objective, power electronics technologies play an essential role and can be contextualized in different purposes to support the full adoption of electric mobility, including on-board and off-board battery charging systems, inductive wireless charging systems, unified traction and charging systems, new topologies with innovative operation modes for supporting the electrical power grid, and innovative solutions for electrified railways. Embracing all of these aspects, this paper presents a review on power electronics technologies for electric mobility where some of the main technologies and power electronics topologies are presented and explained. In order to address a broad scope of technologies, this paper covers road vehicles, lightweight vehicles and railway vehicles, among other electric vehicles.This work has been supported by FCT – Fundação para a Ciência e Tecnologia with-in the Project Scope: UID/CEC/00319/2020. This work has been supported by the FCT Project DAIPESEV PTDC/EEI-EEE/30382/2017, and by the FCT Project new ERA4GRIDs PTDC/EEI-EEE/30283/2017. Tiago Sousa is supported by the doctoral scholarship SFRH/BD/134353/2017 granted by FCT