To transmit constant powers particularly at light load, the isolated dual active bridge (DAB) with conventional dual-phase-shift (DPS) control exhibits large variations of currents, losses, and efficiencies if there is a small change outer phase shift ratio, which caused by command to adjust power transmission. This mainly because narrow operation region ratio DPS modulation used. solve this problem, novel bidirectional inner shifts for DAB developed reduce current surge in high-frequency...

This paper describes a control algorithm for battery energy storage system (BESS) to deliver charge/discharge power output in response changes the grid frequency constrained by National Grid Electricity Transmission (NGET)-the primary electricity transmission network operator U.K.-while managing state of charge BESS optimize availability system. Furthermore, this investigates using order maximize triad avoidance benefit revenues while layering other services. Simulation 2 MW/1 MWh...

This paper presents research from part of a larger project focusing on the potential development commercial opportunities for re-use batteries electricity grid system, subsequent to their primary use in low and ultra-low carbon vehicles, investigating life cycle issues surrounding batteries.The work has three main areas; Examination fleet data detail investigate usage 1 st life.Batteries that have passed through battery recycler at end first been tested within laboratory confirm general...

The switching‐table‐based direct torque control (ST‐DTC) strategies of dual‐three‐phase permanent magnet synchronous machine (PMSM) drives are investigated in this study. Owing to its inherited advantage suppression sixth harmonic pulsation, has attracted more and interests among various sorts multiphase machines. However, unexpected stator currents often observed the classical ST‐DTC strategy for PMSM drives, which cause large losses decrease efficiency drive system. An optimised consists a...

In order to simplify manufacture processes and improve fault-tolerant capabilities, modular electrical machines, especially the ones with segmented stators, are increasingly employed. However, flux gaps between segments often inevitable. this paper, take advantage of these enhance machine performance, novel permanent magnet machines different slot/pole combinations have been proposed. The influence on electromagnetic performance PM such as winding factor, open-circuit air-gap densities,...

In this paper, the operational envelops and efficiency maps of an electrically excited (EE) machine with/without employing flux weakening control via armature current and/or field excitation regulating are obtained comprehensively compared for electric vehicle applications. It shows that even in EE machines, only using but without control, maximum power at high speed is not constant inversely proportional to speed. Only by operation high-speed region can be achieved while greatly extended....

Grid-connected battery energy storage systems with fast acting control are a key technology for improving power network stability and increasing the penetration of renewable generation.This paper describes two research facilities connected to UK electricity grid.Their performance is detailed, along hardware results, number grid support services demonstrated, again results presented.The facility operated by The University Manchester rated at 236kVA, 180kWh, 400V campus network, Sheffield...

This paper presents both the techno-economic planning and a comprehensive sensitivity analysis of an off-grid fully renewable energy-based microgrid (MG) intended to be used as electric vehicle (EV) charging station. Different possible plans are compared using technical, economic, characteristics for different numbers wind turbines solar panels, single hybrid energy storage systems (ESSs) composed new Li-ion, second-life lead–acid batteries. A modified cost (MCOE) index including EVs’ unmet...

A new AC equivalent circuit for the CLL voltage-output resonant converter is presented, that offers improved accuracy compared with traditional FMA-based techniques. By employing describing function techniques, nonlinear interaction of parallel inductor, rectifier and load replaced by a complex impedance, thereby facilitating use analysis methodologies. Moreover, both continuous discontinuous rectifier-current operating conditions are addressed. generic normalized also presented. To further...

This paper presents direct torque control (DTC) methodology for a four-switch three-phase (FSTP) inverter-fed permanent magnet brushless ac (PM BLAC) machine, with reference to conventional six-switch (SSTP) inverter. It has been found that when derived from voltage model flux estimation scheme, the predicted stator imbalance may be caused by unbalanced inverter drop in FSTP inverter, which one phase winding is directly connected dc-link midpoint. While this imbalanced problem does not...

This paper presents four types of three-phase permanent magnet (PM) machines, that is, modular and unequal teeth (UNET) machines either with or without tooth tips. Two-dimensional finite element (FE) modeling has been carried out to analyze the influences flux gaps (in alternate stator teeth) UNET widths. These are mainly on winding factors, air-gap density due PMs, linkage, back-electromotive force, electromagnetic torques. For tips, it found widths affect both factor PMs. However, for have...

Electrical modelling of rail tracks with multiple running trains is complex due to the difficulties in solving power flow. The train positions, speed and acceleration are constantly varying resulting a nonlinear system. In this work, method proposed for DC electric railways support flow analysis simulated metro service. exploits MathWorks simulation tool Simscape, using it model mechanical electrical characteristics track can be provide voltages at any position additionally, seen by train....

This paper presents a capacity planning framework for microgrid based on renewable energy sources and supported by hybrid battery storage system which is composed of three different types, including lithium-ion (Li-ion), lead acid (LA), second-life Li-ion batteries supplying electric vehicle (EV) charging stations. The objective this to determine the optimal size wind generation systems, PV systems (HBESS) with least cost. formulated as mixed integer linear programming (MILP) problem,...

To date, piezoelectric transformers (PTs) have been extensively commercialised in step-up applications, such as cold cathode fluorescent lamp backlighting for LCDs. As step-down PT technology matures, PT-based converters are set to replace conventional and power a wide variety of applications that require relatively low levels, cost, high efficiency, density, small size weight, EMI, reliability. This paper examines the various types transformer provides an overview materials technology,...

Presented is a design for solar photovoltaic (PV) emulator optimised the cost-effective evaluation of solar-array maximum point tracking (MPPT) methods and their associated power converters. The system component calculation methodology are reported with practical comparison output measurements from an actual panel. Unlike previous work in this area compared measurement PV array. results show good agreement between characteristics, demonstrating its suitability static parameter based...

This paper presents a design methodology for LLC resonant converters with capacitor-diode clamp current limiting in overload conditions. A new fundamental harmonic approximation-based equivalent circuit model is obtained through the application of describing function techniques, by examining behavior clamp. An iterative procedure to determine conduction point diode also given. The this type converter analyzed and guidelines designing characteristics are discussed. characterization 90 W using...

The inductorless piezoelectric transformer (PT)-based resonant converter topology allows all the components between half-bridge inverter and rectifier in a conventional LCC to be replaced with single ceramic component. This offers potential savings cost, size, mass. However, zero-voltage switching (ZVS) becomes more difficult achieve because MOSFET output capacitances are augmented by PT input capacitance. paper presents an analytical model for ZVS condition PT-based converters. Unlike...

This paper presents single-layer modular permanent-magnet machines with either wound or unwound teeth tooth tips. The structures having tips are suitable for slot number higher than pole to compensate the drop in winding factor due flux gaps alternate stator teeth, accordingly maintain even increase their average torques. However, lower and hence further improve machine performance. phase back-EMF, on-load torque, iron copper losses, as well efficiency have been calculated using FE analysis...

A normalization of the LCC voltage-output resonant converter performance characteristics, in terms tank gain at resonance and parallel-to-series-capacitor ratio, is presented. The resulting description subsequently used for derivation a design procedure that incorporates effects diode losses finite charge/discharge time parallel capacitor. Unlike previously reported techniques, normalized behavior to identify regions facilitate reduction component electrical stresses, use harmonics transfer...

Reliability and fault tolerance of drive systems has received renewed research interest over last decade with several tolerant topologies control schemes having been proposed investigated. In this paper, the performance hysteresis current vector methodologies when applied to three common investigated compared theoretically experimentally. Their advantages limitations in terms value, torque ripples, operating speed range etc. are considered verified by both simulated measured results. It is...

In this article, a simple position error correction method is proposed to minimize the influence of parameter deviation on model-based rotor estimation, with help two sets windings in dual 3-phase permanent magnet synchronous machine (PMSM). method, when each set individually used for sensorless nominal parameters that are observer identical but inaccurate, which leads errors estimated from both observers. Since varied according current level, small pulses injected respectively into <italic...

An analytical methodology for the rapid steady-state analysis of fourth-order resonant power converters, with capacitive output filter, is proposed. The technique extends previously published work on LCC converters to more common, but complex, LCLC counterpart. filter/rectifier and load circuit are represented by multiple ‘equivalent’ passive components that permit subsequent calculation voltage conversion ratio estimation current stresses resonant-tank components. resulting facilitates...

Conventional converters for radio frequency induction heating usually follow an AC-DC-AC structure, which can exhibit non-unity power factor and introduce large harmonic currents into the utility supply. The need a direct converter heating, featuring unity factor, sinusoidal input current, has motivated development of single phase matrix as heater. A novel commutation strategy is therefore required to ensure smooth operation whilst creating high output under soft switching conditions....