DC fault protection is one challenge impeding the development of multiterminal dc grids. The absence manufacturing and operational standards has led to many point-to-point HVDC links built at different voltage levels, which creates another challenge. Therefore, issues matching isolation are undergoing extensive research addressed in this paper. A quasi two-level operating mode modular multilevel converter proposed, where generates a square wave with controllable dv/dt by employing cell...

Detection of rotor slot and other eccentricity related harmonics in the line current a three phase induction motor is important both from viewpoint sensorless speed estimation as well fault detection. However, it now clear that not all motors are capable generating such current. Recent research has shown presence these primarily dependent on number slots fundamental pole pairs machine. While usually within one to four (higher generally avoided due increased magnetizing current), can vary...

Detection of rotor slot and other eccentricity-related harmonics in the line current a three-phase induction motor is important both from viewpoint sensorless speed estimation as well fault detection. It now clear that not all motors are capable generating such current, however. Recent research has shown presence these primarily dependent on number slots fundamental pole pairs machine. While usually within one to four (higher generally avoided due increased magnetizing current), can vary...

Conventional dual-active bridge topologies provide galvanic isolation and soft-switching over a reasonable operating range without dedicated resonant circuits. However, scaling the two-level to higher dc voltage levels is impeded by several challenges among which high dv/dt stress on coupling transformer insulation. Gating thermal characteristics of series switch arrays add limitations. To avoid use standard bulky modular multilevel bridges, this paper analyzes an alternative modulation...

Renewable energy sources, such as offshore wind farms, require high voltage gains in order to interface with power transmission networks. These conversions are normally made using bulky, complex, and costly transformers high-voltage ac-dc converters unnecessary bidirectional flow capability. Multiple modules of single-switch single-inductor dc-dc can reach without these applications due low semiconductor conduction loss high-power devices. This paper describes a new approach for high-gain...

A multilevel topology with medium-frequency ac link for medium-voltage grid integration of utility photovoltaic (PV) plants is discussed in this paper. megawatt-scale PV plant divided into many zones, each comprising two series-connected arrays. Each zone employs a transformer three secondaries, which interface the phases medium voltage grid. An insulated-gate bipolar transistor full-bridge inverter feeds MF transformer. The voltages at secondaries are then converted to three-phase line...

This paper presents a new configuration for integrated on-board battery chargers of electric vehicles (EVs) incorporating symmetrical six-phase machines. The proposes an exclusive utilization nine-switch converter (NSC) along with the machine windings during both propulsion and charging EVs. proposed has advantage employing reduced number components in EV (on-board) station (off-board), privilege avoiding electromagnetic torque production charging/vehicle-to-grid (V2G) mode operation. During...

One of the main drawbacks nonoverlapped coils in fractional slot concentrated winding permanent magnet (PM) machines are high eddy current losses both rotor core and magnets induced by asynchronous harmonics armature reaction field. It has been shown literature that reduction low space can effectively reduce losses. This paper shows employing a combined star-delta to three-phase PM machine with windings number slots equal 12, or its multiples, yields complete cancellation fundamental...

Power generation through wind is expected to play a major role in the world's future energy portfolio. Nevertheless, power integration remains challenging research area due special characteristics of generation. Specifically, offshore has received significant attention worldwide vast potential available. The electrical infrastructure farms thus importance. multi-terminal HVDC solution represents preferable and shown promise solving farm interconnection problems. Droop control techniques have...

This paper presents a new three-phase inverter based on the Cuk converter. The main feature of proposed topology is that energy storage elements, such as inductors and capacitors, can be reduced in order to improve reliability, reduce size total cost. buck-boost inherent characteristic converter, depending time-varying duty ratio, provides flexibility for standalone grid connected applications when required output ac voltage lower or greater than dc side voltage. property not found...

Two-level voltage-source converters and half-bridge modular multilevel are among the most popular types of HVDC converters. One their serious drawbacks is vulnerable nature to dc-side faults, since freewheeling diodes act as a rectifier bridge feed dc faults. The severity faults can be limited by connecting double thyristor switches across semiconductor devices. By turning them on, ac current contribution into side eliminated dc-link will freely decay zero. main disadvantages this method...

Efficient medium and high-voltage dc-dc conversion is critical for future dc grids. This paper proposes a hybrid multilevel dc-ac converter structure that used as the kernel of systems. Operation proposed suited to trapezoidal ac-voltage waveforms. Quantitative qualitative analyses show said operation reduces footprint, active passive components' size, on-state losses relative conventional modular converters. The scalable high voltages with controllable slope; implying tolerable dv/dt...

This paper studies the effect of stator winding configuration on performance five-phase induction machines under healthy as well faulty conditions. The study compares two connections, namely, star and pentagon connections. comparison is conducted using both simulation experimental results. steady-state model based symmetrical components theory introduced for connections with one-line open due to a converter fault, corresponding machine characteristic curves are estimated. During faults,...

In this paper, the application of a cascaded multilevel inverter as dynamic voltage restorer (DVR) is investigated. Two discontinuous space vector modulation (SVM) techniques are implemented for DVR control and shown to reduce switching losses while maintaining virtually same harmonic performance conventional SVM at high number levels. This paper also presents mathematical relationship computing distortion point common coupling (PCC) function DVR. enables selection levels required certain...

Voltage source converter (VSC)-based high voltage DC (HVDC) transmission is considered the future of offshore power transmission. This paper aims at providing a reliable VSC-HVDC system architecture between wind farms and onshore grids. In this paper, large-capacity, low-speed flywheel energy storage (FESS) based on squirrel cage induction machine applied in parallel with grid side converter. The FESS dedicated for surge (due to flow imbalance during fault) absorption instead being...

Real-time simulation and fast prototyping with power electronics, critical loads, control systems have prompted recent interest in accurate electrical terminal models of photovoltaic (PV) panels array systems. Advancement computing technologies allowed the novel apparatus to be investigated a virtual system under wide range realistic conditions repeatedly, safely, economically. This paper accesses numerical iteration methods, selects appropriate techniques, combines them model construction...

The interior permanent magnet (IPM) machine equipped with a fractional-slot concentrated winding (FSCW) has met an increasing interest in electric vehicle applications due to its higher power density and efficiency. Torque production is both PM reluctance torques. However, one of the main challenges FSCWs their inability produce high-quality magnetomotive force (MMF) distribution, yielding undesirable rotor core eddy-current losses. Literature shows that reduction low-order space harmonics...

Differential-mode buck-boost inverters have merits such as reduced switch number, ability to provide voltages higher or lower than the input voltage magnitude, improved efficiency, cost and size, increased power density, especially in low-power applications. There are five that can flexible output without need of a large electrolytic side capacitor, which degrades reliability inverters. The continuous current these is appropriate for maximum point tracking operation photovoltaic fuel cells...

This paper presents an algorithm that enables single-sensor operation of vector-controlled three-phase permanent-magnet-synchronous-motor voltage source inverter (VSI)-based drive systems. The closed-loop is performed through measuring only the VSI dc-link current. measured current fed to a space-vector-based lookup table, which reconstructs motor line currents. Three Luenberger-style observers are used filter out reconstructed currents and estimate rotor position speed. effect observer...

One of the main merits offered by multiphase machines is their high fault-tolerant capability. Literature has demonstrated that performance induction under fault conditions affected employed stator winding connection. In open-loop controlled five-phase machines, star connection favorable healthy while pentagon and yields a lower derating factor open phase condition. this paper, new combined star/pentagon single layer layout combines advantages both connections proposed for machine. Although...

High-voltage pulse-generators can be used effectively for bacterial decontamination in water treatment applications. Applying a pulsed electric field to the infected sample guarantees killing of harmful germs and bacteria. In this paper, modular high-voltage pulse-generator with sequential charging is proposed via underwater streamer corona discharge. The generator consists series-connected modules similar an arm multilevel converter. modules' capacitors are charged sequentially from...

This paper proposes a six-phase surface-mounted permanent-magnet machine with 24-slot/10-pole fractional slot winding, which not only eliminates the air-gap flux subharmonics, but also minimizes effect of harmonics, highly affect both core and magnet losses. The winding design offers an improved drive train availability for electric vehicle applications due to its inherent high fault-tolerant capability. When compared three-phase design, proposed approximately 3.5% improvement in torque...