A position estimation method for the Synchronous Reluctance Motor (SynRM) based on an inductance model is proposed for light loads operating within the low to medium speed range. Under these conditions, the inductance exhibits a linear relationship with rotor position in specific regions. This linear characteristic of the inductance is utilized to determine the rotor position accurately. Simulations are conducted on a 1.0 kW FEM Model of SynRM prototype, validating the feasibility and effectiveness of the proposed method.

This paper introduces a Reluctance Equivalent (RE) EMF model for sensorless position estimation of synchronous reluctance motors (SynRMs). The unique salient structure of the SynRM results in varying reluctance paths associated with the stator phases. These variations in reluctance cause continuous changes in phase inductance relative to the rotor position, leading to the generation of RE EMF in the stator phase. The RE EMF model is initially analyzed in the abc plane and subsequently transformed into the stationary αβ plane for position estimation. The model’s validity is demonstrated using a Finite Element Model of the developed SynRM prototype

Electric Vehicles (EVs) are gaining importance in many countries in the world as they are clean and cheap mode of transportation. The main issue with EVs is the charging time. Among many methods, pulse charging is one of the methods used for fast charging of Electric Vehicles. To overcome the issue of poor power factor on the source side introduced by diode bridge rectifier, a Power Factor Correction (PFC) circuit is used. The current in the inductor of PFC circuit and the voltage of its capacitor is controlled appropriately to ensure required performance. Conventional control methods in addition with pulsed charging leads to voltage swell and swell at the DC bus due to the presence of multiple energy storage elements. This paper suggests a Modified Control Scheme for PFC circuit to overcome the problem of voltage variation and keep the DC bus voltage variation within a tolerable limit.

Induction Machines employed in electric vehicles (EVs) require variable speed and torque combinations which can be achieved by pole-phase modulation (PPM) technique. In this paper, new winding excitation is analyzed using finite element analysis (FEA) of 6-terminal, 36-slot Induction Motor (IM) drive with 1:2 speed ratio using PPM. It also proposes a new winding technique for Multi-Pole Multi-Phase Induction Motor (MPMPIM) drives with higher slots per pole per phase to achieve the speed-torque combination similar to typical Internal Combustion (IC) engine drives. This approach reduces the leakage reactance, torque and current pulsation with the improvement in overload capacity. Accordingly, winding of the considered IM has been modified to operate with either 3-phase/4-pole or 6-phase/2-pole combinations. The proposed winding excitation gives performance required for EV application like high pole mode for high starting torque during hill climbing and low pole mode during high speed cruising operation. The operation of the proposed drive for different pole-phase combinations with two different speeds is simulated and verified through FEA for 3 HP, 6-terminal, and 36-slot IM drive.

Limited on-board available charge is one of the most important concerns in the wide acceptance of Electric Vehicles (EVs). EVs can be charged either at home or at charging stations. Another solution that appears promising is wireless charging while in motion to extend the range of a vehicle. Concern in this case is availability of the charging infrastructure all along the high-way. There is always a possibility that even though vehicle is enabled for wireless charging, the source system is not available. Under such a situation, an on-board wireless charging system with bi-directional power flow capability can be useful for vehicle to vehicle (V2V) energy exchange. Present paper considers the case of bidirectional V2V energy exchange system. At first such a system is explained and then discussion is extended to the sizing of coil system, circuital arrangements and explanation of different modes of energy exchange. Operation of the system is explained with the help of simulation results to justify the possibility.

Battery-powered Electric Vehicles (EVs) are considered as an effective solution to curb carbon emissions and fight global warming. One of the main drawbacks in driving an EV is range anxiety, which can be defined as the fear of vehicle having insufficient range to reach its destination due to lack of charging. Vehicle-to-vehicle (V2V) charging is being explored as a solution to mitigate the range anxiety issue. V2V charging allows the sharing of charge between two EVs so that if an EV is stranded far from a charging station, it can be charged from another EV. Various V2V chargers have been studied. It has been found that the traditional chargers involve many power conversion stages, which reduces the efficiency in the energy exchange. In this paper, an off-board DC V2V charger is presented. It reduces the power conversion stages while dispensing with the use of any on-board charger. To implement the off-board DC V2V charger, a bidirectional DC-DC converter is adopted. The converter operates in various modes, depending upon voltage and state of charge of the EV batteries. In turn, the V2V charging is managed in an automatic way. Operation modes and management program of the off-board V2V charger are discussed in the paper.

The paper is concerned with the wireless power (WP) systems feeding in-motion electric vehicles (EVs) and focuses on the power sizing of three key WP system components, namely the track coils, the pickup and the voltage supply. It is assumed that the track is made of lumped type with no overlapped coupling of the pickup, and that the track coils and the pickup are compensated for by series resonating capacitors. Power sizing equations are formulated for a WP system that is controlled in the way of transferring a constant power to EVs during their motion over a large part of the track coils. Due to the variation of the coupling between the pickup and a track coil, the transfer of a constant power requires the adjustment of the currents in the WP system, obtained by commanding the embedded power conversion units. Two solutions are examined: by one solution, the pickup side current is controlled at a proper value whilst the track side current is regulated at a constant level; by the other solution, the opposite occurs. Power sizing equations are expressed in terms of specifications and parameters of the WP system. The equations outline that the power sizing is higher for the components in the side where the current control is executed. At last, the case study of a WP system is examined, showing the convenience of the track-side control.

In this paper comparative evaluation of temperature regulated pulse and reflex charging is carried out to comment on the suitable method for fast charging of a Valve Regulated Lead Acid (VRLA) battery. Electro-thermal model of the battery is used as an estimator to measure associated variables such as instantaneous battery current, terminal voltage, state of charge, charge deposited and temperature. Width of the charging pulse has been varied as per the estimated temperature to keep the battery temperature regulated. It is noticed that for both the cases faster charging can be achieved with an increase in temperature reference. It is demonstrated that pulse charging strategy improves the charging speed 10% more than reflex charging strategy.

This paper proposes a DC-AC converter capable of delivering pure sinusoidal voltage and current to resistive as well as inductive load. The proposed converter provides a quadruple boost while converting low-level DC input to high voltage low total harmonic distortion (THD) AC voltage. Switches operate at fundamental frequency resulting in negligible switching loss. Peak inverse voltage (PIV) as seen by switches is equal to input DC voltage therefore total blocking voltage (TBV) of the proposed converter is nominal and signifies lower semiconductor cost and loss enhancing the efficiency. The working principle is illustrated in detail with the simplified equivalent circuit. Experimental validation of the proposed converter has been done on a 1kW prototype.

Due to its voltage-fed nature and capacitive output filter, rear-end rectifier (RER) of series-parallel resonant converters with capacitive filters draw discontinuous currents. Not only simple and elegant techniques such as Fundamental Harmonic Approximation (FHA) analysis, but also time domain, state space and state-plane approaches also fail to model such converters with reduced labor. A recent study introduced technique to restore the simplicity of FHA analysis concerning such converters. Therefore, detailed discussion of available FHA modelling techniques in relation to series-parallel resonant converters with capacitive filters and their comparison is presented in this paper.

Keeping in mind the need to counter climate change, our rapidly growing demand for energy needs not to be heavily derived from conventional and exhaustible sources such as coal and oil but be offloaded in phases to their inexhaustible and cleaner counterparts such as solar, wind and hydro. Henceforth, this paper proposes a model of an electric vehicle (EV) charging station connected to a photovoltaic (PV). The PV fed bus system modelled in this paper includes a maximum power point tracking (MPPT) algorithm, a boost converter and 10 e-rickshaws as EVs being connected to the bus at different intervals of time. The impact that switching ON of charging of the EVs can have on the PV fed bus is discussed along with a strategy to mitigate it.

Lighting of heavy duty vehicles like trucks, buses and trains has been mainly implemented with fluorescent lamps and inverters, and is being now upgraded to LED (Light Emitting Diode) new technology. Given the normative lighting requirements (measured in lux), added to the aggressive environment of automotive application and its specifications, the high flux, improved efficiency mid and high power LED's are becoming the most practical and smart solution for city and coach transportation. One of the relevant factors on PCB design of LED lighting is LED junction temperature, which depends on the type of power supply employed, pad temperature and construction factors. This paper aims to shows the uncertainty on junction temperature measurements through Monte Carlo method. This technique uses randomly generated input variables in a mathematically built model (plant), to obtain the combined uncertainty output estimation. After the evaluation of all uncertainty factors that influence the LED and its switched power supply's thermal behavior, the model is extensively simulated showing that the significance of the junction temperature variation is finally taken, in terms of the input manufacturing and environmental parameters.

In general, Light Electric Vehicle applications mostly prefer Permanent Magnet Synchronous Motors (PMSM) with nominal power up to 2kW. With the objective of to explore the feasibility of non-permanent magnet solution in this category, present paper considers the design and analysis of 1.5kW Synchronous Reluctance Motor (SynRM) with concentrated type winding. Design has been carried out to determine the dimension of the stator and rotor structure, and calculation of winding parameters. The designed data is verified and optimized through Finite Element Method (FEM) analysis. The distribution of flux lines and flux density on stator and rotor periphery is also presented. Rotor structure has been optimized with respect to the variation in flux barriers per pole to ensure improved torque performance specially torque ripple and average torque.

Battery temperature is a key performance metric that drives greater importance due to recent development in fast charging methodologies. This paper presents a discrete time thermo-electric battery model which estimates instantaneous battery temperature. Proposed model is then subjected to a temperature sensitive control system which determines the pulse width of the pulse charging operation. Simulation results indicate the range of charging current magnitude in which fast charging is possible while maintaining the battery temperature in a safe operating zone.

Wireless power transfer (WPT) is the future solution for electric vehicles due to its merits compared to conductive charging. The main obstacles to WPT are efficiency and power transfer capability. Compensation topologies play a key role in improving efficiency and power transfer capability of WPT. This paper carries the evaluation of electrical parameters for wireless charging of an e-Rickshaw through Series-Series (S-S) and Parallel-Series (P-S) topologies of coil system. Evaluated parameters are verified through MATLAB simulations of equivalent system. At the end, based on analytical and simulation studies comparative evaluation of S-S and P-S topologies is carried out.

Present paper demonstrates the effectiveness of the predictive deadbeat current control for Permanent Magnet (PM) Brushless (BL) DC motor drive in injection of square-wave phase current even at higher speed as compared to conventional PI controller employed for phase current control. Effectiveness has been demonstrated in terms of capability of minimizing current ripples and torque ripples ensuring the higher average torque, maximizing the utilization of constant torque zone of operation. Control has been implemented through the concept of stationary plane base approach for PM BLDC drive.

DC-DC switched mode converters are nonlinear and time variant systems, and do not lend themselves in the application of linear control theory. Control strategies for these controllers are now mature but still attempts are being made towards the improvement of performance in event of disturbances. The state space average method is readily used for modeling and design of these controllers. In this paper, PI and deadbeat controller design are implemented for DC-DC buck converter particularly in distributed energy systems. It is found that, the deadbeat controller gives improved dynamic response compared to PI within 10 switching cycles of the time. Therefore, this controller can be effectively applied in renewable energy system applications like wind, solar and hybrid systems for efficient charging of battery and also for DC load control.

Five-phase PM BLDC drives are a viable solution for safety-critical applications in road traction and aeronautics sectors. A common supply technique for these drives consists in the injection of square-wave currents into the motor phases, synchronized with the flat-top portion of the back-emf to produce both constant torque and maximum torque per ampere. In practice, the currents deviate from the ideal shape during the phase commutations, which further affects the torque characteristics of the drives. This paper analyzes the current behavior during the phase commutations for the five-phase PM BLDC drives as they exhibit some differences with respect to the three-phase counterpart. Then it uses the outcomes of the current analysis to derive the effective torque developed and the torque ripple exhibited by the drive as a function of the motor speed. The base speed of the drive is also determined. Throughout the paper, the differences from the well-known operation of the three-phase PM BLDC drives are pointed out.

The paper investigates the behavior of permanent magnet (PM) brushless DC (BLDC) drives in the stationary plane. The vectors of the phase currents and back-emfs are first drawn under ideal square-wave current supply. Development of a constant torque from the motor is explicated with the help of the vector representation. Trajectories of the tips of the motor current and voltage vectors are then traced for various motor speeds taking into account the phase commutations. Torque developed by the motor and its ripple are determined from the vector tip trajectories. Theoretical findings are supported by simulation results obtained by using the data of a PM BLDC drive designed for the propulsion of electric vehicles.

PM brushless DC (BLDC) motors should be fed by square-wave currents synchronized with the back emfs to develop a constant torque with the required value. In practice, phase inductances and limited source voltage produce non ideal square-wave currents and unbalanced phase currents during commutations. Such phenomena affect the torque developed by the PM BLDC drives by deviating its value from the requested one and by giving rise to torque ripple. In this paper, an analytical study of the torque characteristics, namely motor torque and torque ripple, of PM BLDC drives is carried out as a function of the motor speed and is supported by experimental data. Torque characteristics are expressed in terms of a quantity distinctive of the motor, thus giving a generalized formulation to the results.