Conventional Model Predictive Control (MPC) for Active Neutral Point Clamped (ANPC) converters requires a complex tuning of weighting factors in its multi-objective cost function. This paper proposes a Sequential Predictive Current Control (SPCC) strategy that eliminates the need for such weighting factors, simplifying controller design for reactive power compensation applications. The proposed method employs a two-stage sequential optimization: first, it identifies a candidate subset of switching states that minimizes current tracking error, and second, it selects the optimal state from this subset to ensure DC-link capacitor voltage balancing. The resulting optimal voltage reference is synthesized by a standard Pulse Width Modulation (PWM) stage, which ensures a fixed switching frequency and improves the harmonic spectrum compared to direct MPC methods. This sequential approach decouples the control objectives, offering a simpler and more robust tuning process. Simulation studies validate the strategy, demonstrating excellent reference current tracking and robust voltage balancing while maintaining low harmonic distortion in the source current.

This paper proposes a Sequential Model-Based Predictive Current Control (SMBPC) integrated with Space Vector Modulation (SVM) for reactive power compensation in three-level Neutral Point Clamped (NPC) inverters. The sequential approach optimizes reference current selection and capacitor voltage balance, employing a two-stage cost function to minimize voltage imbalance. Additionally, this work approach obviates the need for weighting factors, as the cost function is not multi-objective, streamlining the optimization process and reducing computational complexity. Simulation studies are provided to show the effectiveness of this proposal demonstrating accurate current reference tracking.

The three-phase single-stage differential boost inverter (DBI) has drawn significant attention in power conversion systems when feeding permanent magnet synchronous motors (PMSM). It offers advantages such as single-stage boosting, high efficiency, cost-effectiveness, and a compact structure. However, its nonlinear and non-minimum phase characteristics pose challenges for control. In this paper, the application of model predictive control (MPC) for PMSM fed by the three-phase DBI is focused on. Firstly, the modeling method of the three-phase DBI is presented. Subsequently, an MPC approach for PMSM fed by three-phase DBI is proposed. Based on the established predictive models of circuit currents and voltages, the appropriate duty cycle for the next sampling period can be predicted, which simplifies the control process and parameter design compared to traditional exclusively PI-based control. Simulation experiments are carried out to verify the effectiveness of the proposed MPC strategy for PMSM driven by the three-phase DBI.

This paper addresses the problem of optimizing the ultrasonic shock wave signal gain based on the Time - Reversal Mirror (TRM) technology. A method system combining channel modeling, Virtual Time - Reversal Mirror (VTRM) simulation, and adaptive frequency - domain modulation is proposed. The research estimates the transfer function of the dispersive waveguide, analyzes the signal transmission characteristics in complex media through VTRM simulation, and further designs two frequency - domain modulation methods: frequency - domain windowing and frequency - domain iterative weighting. These methods optimize the spectral characteristics of the TRM excitation signal, thereby enhancing the energy focusing effect of the shock wave. The simulation results show that the optimized TRM method can effectively improve the shock wave gain and has a stronger signal enhancement ability compared with the traditional method. This optimization method can effectively overcome the limitation of the focusing performance of the traditional TRM technology in complex media, providing theoretical support for the design and optimization of ultrasonic shock wave signal generation devices.

The three-phase differential boost inverter is a special type of power inverter that offers single-stage boosting capability, combining high efficiency, low cost and compact size. However, it is complicated to control due to its non-linearity. Conventional open-loop control and dual-loop proportional-integral (PI) control is realized through the pulse width modulation (PWM). This paper reviews the basic principles and conventional control methods of the three-phase differential boost inverter. Then, a model predictive control (MPC) method of the three-phase DBI is proposed. Based on the established discrete models of circuits currents and voltages, the optimal switching state can be selected relying on a predefined cost function. Simulation studies are carried out to verify effectiveness of the proposed MPC of three-phase DBI.

The boost converter-based single-stage buck/boost inverter overcomes challenges that step-up voltage limitations of traditional voltage source inverter, the increased cost and control complexity of two-stage inverters, and the limited step-up range of single-stage impedance source inverters. Whereas, its ac output includes a dc bias at the value of dc source voltage and ac load voltage amplitude. Therefore, its boost ratio would be still limited because of the voltage rating limitation of practical power devices. This paper proposes a novel high-gain single-stage buck/boost inverter, without loss of low voltage stress and high boost ratio. The topology, operating principle, and modulation are disclosed. Simulation studies are carried out to demonstrate effectiveness of the proposed inverter.

The permanent magnet synchronous motor (PMSM) is widely adopted in the industry. However, current testing systems for PMSM drives exhibit several limitations. This article proposes a quasi-Z source inverter (qZSI) based PMSM emulator, which can emulate a PMSM with different test schemes under different working conditions. The motor emulator (ME) proposed in this paper is able to solve the inherent defects of the traditional inverter. Improve the quality of output voltage and the reliability of inverter system. In this paper, the parameterized model of PMSM and mathematical model of the qZSI are established firstly. Based on that, the PMSM emulator is developed and tested for different operating conditions. Matlab simulations have been used to verify the viability and efficiency of the system.

Due to their single-stage step-down nature, current source rectifiers (CSR) constitute attractive options for supplying high-power electrolyzers. To increase system power rating, parallel configurations can be adopted with interleaved Pulse Width Modulation (PWM) techniques that improve power quality and reduce the size of filtering elements. Optimal design of the output dc inductance is crucial to achieve cost-effective and competitive solutions. However, common design methods for one single CSR do not achieve optimal designs. There are hardly any specific design methods for interleaved CSRs either. This paper analyzes the operation of parallel interleaved CSRs supplying high-power electrolyzers and develops a methodology to optimally size the output dc inductances. In addition, a common mode equivalent circuit is developed to analyze the circulating currents caused by the interleaved operation and calculate the ripple in the inductances. When applied to a 3 MW electrolyzer, the results show that inductance size reductions of up to 69% can be obtained with the proposed methodology.

Power electronic converters play a pivotal role in integrating renewable energy sources into the grid or standalone electrical power systems by converting and conditioning the generated power, achieving a sustainable future and reducing greenhouse gas emissions. This paper focuses on implementing an asymmetrical cascaded H-bridge multilevel power converter with hybrid modulation for on-grid solar photovoltaic generation systems. Specifically, this paper introduces a predictive current control and reactive power compensation capability. The paper evaluates the efficiency of the proposed system in terms of generated energy quality and the effectiveness of the predictive control strategy.

To address the state-of-the-art challenges of variable-speed drives, this paper introduces Direct Speed Predictive Control (DSPC) for Induction Motor (IM) drive systems. DSPC eliminates cascaded control structures and enhances control performance by directly managing speed without intermediary loops. This approach promises improved dynamic response, operational efficiency, and adaptability across industrial applications, making a significant advancement on IM control technology. The proposed control method was validated via simulation results across different operational scenarios such as varying loads, speed fluctuations, dynamic changes, and parameter inaccuracies to assess its effectiveness. The outcomes affirm its reliable control performance.

Photovoltaic (PV) power station is an inverter cluster with a single grid connected inverter as the unit. The resonance frequency shift caused by the grid impedance of the inverter cluster under weak grid is more serious. In this paper, Dual-Division-Summation (D-D-$\Sigma$) current control strategy is extended to inverter cluster to solve the more serious problem of resonant frequency offset. A derivative curve of logarithmic amplitude frequency characteristic curve is used to analyze the resonance characteristics, and the change of resonance characteristics caused by equivalent grid impedance is analyzed mathematically. Aiming at the resonance characteristics after the equivalent impedance is enlarged by$N$times, a resonance suppression strategy of inverter cluster under weak grid is proposed. The control gain of the resonance suppression strategy is obtained through the Routh Criterion, which can consider the wider range of resonance frequency offset. The experimental results verify the correctness of the above analysis.

To meet the urgent demand for high efficiency and high power density inductive power transfer (IPT) system in key applications such as electric vehicles, deep-sea intelligent equipment and consumer electronics, this article proposes a novel IPT system with full range soft-switching operation and magnetic integrated structure based on the dual-decoupling concept. With the help of the novel active auxiliary network, the switching tubes in the high-frequency inverter can achieve zero-voltage switching (ZVS)-ON and ZVS-OFF within the full power range. Meanwhile, the proposed magnetic integrated structure based on the dual-decoupling concept integrates the resonant inductor in the auxiliary circuit and compensation network into the transmitter coil, sharing a set of magnetic core. It can achieve the decoupling between the auxiliary resonant inductor and the compensation resonant inductor, as well as the decoupling between the two resonant inductors and the power transfer coils, with the effect of suppressing leakage flux and reducing the proximity effect of high-frequency currents. The proposed dual-decoupling concept can be extended to other high-order compensation IPT topologies with multiple resonant inductors. The above schemes can effectively reduce the system’s switching losses and the overall core losses of the system, improve the transfer efficiency of the system across the entire power range, and possess many advantages such as high power density, efficiency, and magnetic flux balance. Eventually, the advantages of the proposed scheme are validated through the construction of a 1kW experimental prototype.

The usage of an Auxiliary Resonant Commutated Pole (ARCP) circuit with an 11-level Cascaded H-Bridge (CHB) converter as an option for feeding high-power Wireless Power Transfer (WPT) track-pads in traction applications is proposed in this research. By utilizing a mathematical model to obtain the switching pulses of the ARCP circuit, a reduction in the conduction losses of the involved inductance can be achieved. Moreover, an optimization routine is developed to reduce the MOSFETs' root mean square current by finding each module's phase shift angles. The study uses the SAE J2954 standard to restrict the Electromagnetic Interference (EMI) in the frequency band between$400\ kHz$and$30\ MHz$. The success of the suggested technique is displayed by simulation results showing that it is possible to operate the CHB with Zero Voltage Switching in all modules of the power converter. Inductive Power Transfer applications applied in railways can benefit from this contribution due to the use of multilevel converters.

The simplified modeling of a complex system allied with a low-order controller structure can lead to poor closed-loop performance and robustness. A feasible solution is to avoid the necessity of a model by using data for the controller design. The Virtual Reference Feedback Tuning (VRFT) is a data-driven design method that only requires a single batch of data and solves a reference tracking problem, although with no guarantee of robustness. In this work, the inclusion of an H∞ robustness constraint to the VRFT cost function is addressed. The estimation of the H∞ norm of the sensitivity transfer function is extended to maintain the one-shot characteristic of the VRFT. Swarm intelligence algorithms are used to solve the non-convex cost function. The proposed method is applied in two real-world inspired problems with four different swarm intelligence algorithms, which are compared with each other through a Monte Carlo experiment of 50 executions. The obtained results are satisfactory, achieving the desired robustness criteria.

Aviation is a significant contributor to greenhouse gas (GHG) emissions in the transportation sector. As the adoption of electric cars increases and GHG emissions due to other modes of transport decrease, the impact of air travel on environmental pollution has become even more significant. To reduce pollution and maintenance, and ensure cheaper and more convenient flights, industry and academia have directed their efforts toward aircraft electrification. Considering various types of aircraft, several frameworks have been proposed: more-electric aircraft (MEA), hybrid electric aircraft (HEA), and all-electric aircraft (AEA). In the MEA framework, propulsion is generated by a conventional jet engine; however, all secondary systems (hydraulic, pneumatic, and actuation) are electrified. By further increasing electrification, electric motors can provide propulsion with the electric power supplied by the conventional engine (i.e., HEA) or from electrical energy storage (i.e., AEA). Power electronics and electrical machines play a key role in this scenario in which electric power must be efficiently generated, distributed, and consumed to satisfy extremely high requirements of aviation safety. This article provides an overview of recent advancements in aircraft electrification, and trends and future developments referenced to the global aviation roadmap.

Submodule losses for Modular Multilevel Converter (MMC) are frequently inferred based only on the number of components. This procedure lacks support because Submodule losses also depend on other conditions. In this work, the simulation of different Submodules with various pulse-wide modulation (PWM) techniques for MMC was performed. A new approach to fairly compare Submodule losses is proposed considering Clamp Single (CS), Clamp Double (CD), Full Bridge (FB), and Cross Connected (CC) submodule topologies. The PWM techniques applied were Phase Shifted (PS), Level Shifted Phase Disposition (LSPD), and Space Vector (SV). In addition, IGBT and SiC MOSFET devices were also considered, and DC sources were used instead of Submodule Capacitors to avoid balancing algorithms. A 9-level Three-phase MMC was developed for simulation purposes. The results show that FB, CS, and CC based MMCs present the same losses when LSPD PWM or SV PWM are applied. CD based MMC shows the overall lowest losses, except when PS PWM and IGBT are used becoming the CC based MMC the lower losses submodule in that case. These simulation results support the importance of taking a holistic approach when comparing Submodules for MMC applications.

To eliminate the common-mode voltage (CMV) for matrix converters, this paper proposes a current sensorless model predictive control with reduced calculation overhead. In contrast to other traditional CMV-reducing methods which use all permissible switching configurations, this method synthesizes the output voltage and the input current with only six rotating vectors that lead to zero CMV. The proposed technique does not need to predict future load currents and source currents for those six rotating vectors, which provides another advantage in term of computation efficiency. Additionally, all current sensors are removed by using a Luenberger state observer instead in the control loop for cost reduction. The effectiveness of the proposed method is evaluated through simulation in different operation conditions.

Model Predictive Control (MPC) is becoming more popular than ever as an alternative to conventional modulations such as Space Vector Modulation methods to control matrix converters (MCs). However, the implementation of MPC is computationally expensive, because control objectives are required to evaluate all admissible switching states of the converter. Additionally, a large number of sensors to measure the 3-phase load currents, source currents, source voltages, and input voltages of MCs increases the overall cost. To sort this out, an efficient MPC is proposed for MCs to enable fast computation and low cost. This approach eliminates the calculations of future load currents and source currents for all possible switching states, requiring only two predictions for the calculation of output voltage and input current references. Further, it removes all current sensors by employing a Luenberger observer. A simulation study has demonstrated that the proposed method can reduce the computation overhead and hardware cost dramatically, leading to high-frequency operation and good converter performance.

A Half-bridge-active-clamp (HBAC) converter is used as an alternative to replace Dual active bridge (DAB) converter for 540V/28V on-board grid in more electric aircraft applications. The HBAC converter provides an opportunity to reduce the turn-ratio of the high frequency transformer compared to DAB converter with reduced current stress on the low voltage side benefit from a current-fed LV bridge. HBAC converter shows a much better performance both on efficiency and volume compared to conventional DAB converter. In addition, a Model Predictive Control (MPC) method for LV output current regulation is proposed based on HBAC converter with the aim of achieving fast dynamic performance.

Multi-phase wind generation systems are emerging as a promising technology for distributed generation systems. These systems can present unbalanced voltages or phase faults for several reasons. In this paper a modular three-phase direct matrix converter topology is used as conversion stage in a six-phase generation system to supply the desired current to a load. To achieve a reliable performance in the conversion stage, an improved predictive current control is proposed that take advantage of the modularity of the converter to enhance the behavior and to provide the capability to work continuously even under unbalance in the source or during fault operation of the generation system whilst achieving the desired tracking and power quality. The technique is compared against a classical approach to show the benefits of the proposed.

Distributed energy resources and new loads such as fast charging stations for electric vehicles are often dc-based. By using low-voltage dc microgrids to connect such systems to the grid, conversion stages can be omitted and higher efficiencies can be achieved. Challenges exist with respect to the protection of dc microgrids, where dc fuses are a viable solution but selective tripping must be ensured. The grid-forming converter must be able to supply the fault current in the case of a line-to-line short-circuit in a feeder without tripping due to over-current. To avoid expensive over-sizing, this paper proposes to use a virtual resistance in the control of the grid-forming converter to limit its output current. The range of the virtual resistance is discussed for normal grid operation and the effect of the virtual resistance on limiting the bus current during a short-circuit fault is discussed. In addition, the impedance models of the source and load systems are presented. Based on this, the influence of the virtual resistance on the system stability is analyzed. To validate the theoretical part, a switching model is simulated and the results show a good agreement with the theoretical analysis.

The idea of electric propulsion for transportation is not new; indeed, the first cars, nearly 200 years ago, were electric. However, our dependence on fossil fuels over the last 100 years is now being questioned, and as a global society, we are moving toward more-electric transportation solutions. Electric propulsion of aircraft is part of this trend, either all-electric or through a large variety of the proposed hybrid propulsion systems. This article considers some of these systems, their technological requirements, and the ongoing research and development in motors and drives necessary to make this technological change a feasible option for the future of passenger flight.

Isolated DC/DC modular multilevel converters (MMC) consisting of two MMCs isolated by a transformer are one of the converter topologies being considered used for DC/DC conversion in HVDC transmission. Two level modulation can be used to obtain different voltage levels by inserting/bypassing a specific number of sub-modules (SM) in the converter circuit. However, it does not take into account the SM's voltage when elevation factors need to be readjusted, which results in either higher or lower output voltage than the reference. This paper proposes a finite control set model predictive control (FCS-MPC) for output voltage regulation to the reference value. A cost function comprising the output voltages is defined and a mathematical equation is formed to calculate the one step ahead value of output voltage. The number of SMs which minimize the cost function is applied to the converter circuit. Voltage balancing amongst the sub-module cells has been achieved by using a sorting algorithm. The performance of the proposed control strategy is evaluated and verified.

Unbalanced three-phase voltages, harmonics and DC offset to the grid voltage will affect the speed and accuracy of a grid-connected inverter when estimating the frequency and phase angle of the grid voltage. Existing synchronization methods were difficult in accurately estimating the phase angle of the three-phase voltages. To solve these problems, this paper proposes a synchronous control method for three-phase grid-connected inverters using the energy operator. First, the cascade delay signal cancellation algorithm is used to eliminate harmonics and DC offset of the grid voltage, and the grid voltage is unitized to eliminate the adverse effects of unbalanced amplitudes. After that the energy operator is applied to obtain the frequency and the phase angle of the thee-phase input voltages. Therefore, the inverter and the grid voltage can be accurately synchronized even under unbalanced grid voltage conditions with harmonic distortion and DC offset. Finally, simulation results are used to verify the effectiveness of the synchronous control method proposed in this paper.

In this paper the potential of the modulated model predictive control (MMPC) to control a matrix converter (MC) in the linear- and over-modulation zone is investigated. Input and output current references of MC are usually used to define the control objective in MMPC. By considering the predicted input and output currents of MC, a conventional space current vector modulation equation can be formed. As a result, control of the load and supply currents, good steady state performance and fixed switching frequency are achieved in the linear zone. Moreover, the transition time between the linear- and over-modulation modes is minimized by considering a new reference vector through a simple calculation. The feasibility of proposed method is demonstrated by simulation results and proved that the resulted controller includes the advantages of model predictive control (MPC) and space vector modulation (SVM) and effectively working in the different modes of operation.

One of the challenges brought forward by the gradual electrification undertaken by the aviation sector is the requirement of fault tolerance for machine drive systems to be used for critical on-board tasks such as propulsion or primary flight surface actuation. Their inherent advantages in both volumetric and gravimetric power density makes integrated drives the prime candidates for these applications. Despite the large advances in this field, few key area still need work. Key among which is fault tolerant current control strategies. This paper studies the application of resonant control techniques to achieve a scalable and fault tolerant current control strategy for multiphase machine.

This paper presents an enhanced modulation technique for dual converters with isolated supplies. This unified modulation technique is applicable for any positive voltage ratio between the isolated supplies. The modulation technique enhances the quality of converter output voltage. The effectiveness of the proposed technique is validated and results are presented for an open-end winding induction motor to demonstrate the advantages.

This paper explores the possibility of a semiconductor-based over-current bypass circuit for high current solid-state power controllers (SSPCs). Therefore, two different topologies of the bidirectional DC SSPCs: a. without over-current bypass circuit b. with an over-current bypass circuit are presented for the same power ratings. The first SSPC consists of a parallel matrix connection of the discrete MOSFET devices (conducts during nominal and over-current conditions) and the second one is designed with fewer MOSFET loops (conducts during nominal condition) and additional IGBT modules matrices to bypass the over-current. The thermal performances of both the SSPCs are evaluated analytically and compared during the nominal and over-current situations. Later, the PLECS simulation models of the SSPCs are developed and the junction temperature of the devices are estimated. The overall weight, power density, and cost of these two SSPCs are approximated for the comparison. It is found that the SSPC topology with bypass circuit exhibits better power density and lower cost. Therefore, it can be employed to replace the tradition circuit breakers for the more electric aircraft (MEA) in the near future.

The development and validation of an advanced two-level Voltage Source Back-to-Back Converter model, considering its multi-physics operation, is presented in this paper. Based on a set of input parameters, the proposed model evaluates the converter in terms of input current ripples, transient performance, losses, and total volume. The model is discussed separately in three parts: modulation and control analysis, semiconductor loss estimations and heatsink sizing, and passive components sizing, i.e. for the boost inductors and DC-link capacitor. The performance analysis and loss calculations are verified to be accurate using time-domain simulations and experimental loss measurements. Due to its computational efficiency and accuracy, the proposed model is suitable for use within an optimization design environment.

Mechanically-driven actuators, compressors and pumps are being replaced by the aircraft manufacturers that shift the trend towards “More Electric Aircraft” and hence reducing the mechanical linkages within the aircraft system. This elevates the dependence of the electrical power on the main engine, deicing and cabin environmental system which originates from the starter-generator. This paper presents a trade-off study for the design of high-performance starter-generator, surface-mounted permanent magnet machines, considering slot-pole combination, winding configuration and geometrical layout as degrees of freedom while satisfying the output power and strict volume requirements. 18S/12P combination seems a promising candidate for starter generator application which satisfy all the given requirements, giving the output power of 32kW at 14kRPM within the volume of 1407cm3.

The concept of multiport dc-dc converter was proposed to reduce the conversion stages of dc microgrid on more electric aircraft (MEA). The structure of multiport dc-dc converter is basically developed from the dual active bridge (DAB) converter because of its galvanic isolation and bidirectional power flow. A power electronics converter as a key element of the electrical power distribution system may cause stability issues. To address these challenges, the impedance characteristic of the multiport converter will be analyzed. In this paper, a transfer function based small signal model is developed and validated with a switching model, to figure out the characteristic of input impedance of triple active bridge (TAB) converter. Preliminary experimental results are presented to be as a support.

This paper gave a design guide of the direct matrix converter (DMC) open circuit fault diagnosis methods in industrial applications. Two fault diagnosis methods are presented in this paper. One fault diagnosis method is for a DMC using a space vector modulation (SVM) strategy. The other fault diagnosis method is for a DMC using a finite-control-set model-predictive-control (FCS- MPC) strategy. The design guide is given based on the comparison of these two fault diagnosis methods.

A modulated model predictive control (M2PC) scheme for an indirect matrix converter is proposed in this paper, including an active damping method to mitigate the input filter resonance. The control strategy allows the instantaneous power control and the output current control at the same time, operating at a fixed frequency. An optimal switching pattern is used to emulate the desired waveform quality features of space vector modulation and achieve zero-current switching operations. The active damping technique emulates a virtual resistor which damps the filter resonance. Simulation results present a good tracking to the output-current references, unity input displacement power factor, the low input-current distortions and a reduced common-mode voltage (CMV).

Dual-active-bridge (DAB) DC-DC isolated converter is widely used in many applications e.g. power supplies, transportations and renewable power systems. In this paper, general modulation characterization and optimization of DAB converters have been analyzed and advanced modulation methods are proposed. Simulations and experiments are implemented to verify the effectiveness of the proposed modulation strategies.

This paper describes the application of a simplified indirect model predictive current control strategy for a direct Matrix Converter. The direct matrix converter has a large number of available switching states which implies that the implementation of predictive control high computational cost. In this paper, a predictive current control strategy is proposed in order to simplify the computational cost while avoiding the use of weighting factors. The method is based on the fictitious dc-link concept, which has been used in the past for the classical modulation and control techniques of the direct matrix converter. The proposed controller is enhanced with a fixed switching predictive strategy in order to improve the performance of the full system. Simulated results confirm the feasibility of the proposed controller demonstrating that it is an alternative to classical predictive control strategies for the direct matrix converter.

Predictive control has recently emerged as a promising alternative to more traditional methods for the control and modulation of power converters. This paper presents an overview of predictive control techniques applied to matrix converters. The paper highlights that predictive control strategy is a promising alternative to conventional modulator based linear control for matrix converters due to its simplicity and flexibility to include additional constraints within the control to have it suitable for different applications. In addition to describing many advantages of predictive control techniques, its limitations and weaknesses are also discussed along with some future trends and applications. Most important control aspects of predictive control are demonstrated through simulation analysis.

This paper studies strategies to minimize the electromechanical interaction (EMI) within aircraft power systems. With the growth of electrical power on-board aircraft, the interaction between the electrical systems and the engine core will become significant. The behaviour of electrical loads (on/off, transient etc.) will have significant impacts on the engine shaft, such as producing transient vibrations, creating stability problems and reducing the efficiency etc. To avoid these problems, an advanced electrical power management system (PMS) is required. This paper introduces novel loading methods for PMS applications to minimize the interactions between electrical and mechanical systems. The strategies, referred as Single Level Multi-edge Switching Loads (SLME), Multilevel Loading (MLL), and Multi-load Single Level Multi-edge Switching Loads (MSLME) are developed based on the Posicast method. An insight look of the developed technique has been studied using the zero-pole root locus. It is demonstrated that the excited poles in the system are cancelled by the addition of zeros, and thus suppressed the EMI vibrations.

In the last past years, some countries are enforcing stringent grid codes to regulate the connection of Wind Energy Conversion Systems (WECSs) to the electrical network, mainly because of the high penetration of electric power from this renewable source. Additionally, the trend of wind turbines has shown an ongoing power rating growth, reaching sizes up to 10 MW. Multilevel converters have appeared as a solution for large WECSs, due to its high reliability, controllability and the capability to reach high power ratings. This paper presents a control strategy for the application of the Modular Multilevel Matrix Converter in Multimegawatts Wind Turbines. Extensive computer simulations and a downscaled laboratory prototype, with twenty-seven power cells, are presented to validate the effectiveness of the proposed control system.

The Modular multilevel matrix converter (M3C) is a promising topology for medium-voltage, high-power applications. Due to the modular structure, it is scalable, produces high quality output waveforms and can be fault tolerant. However, the M3C suffers from capacitor-voltage fluctuation if the output frequency is similar to the input frequency. This problem could limit the circuit's application in the adjustable speed drives (ASD). This paper introduces a theoretical analysis in the phasor-domain to find the branch energy equilibrium point of the M3C when operating with equal input and output frequencies. On the basis of this equilibrium point, a branch current reallocation based energy balancing control method is proposed to equalize the energy stored in the nine converter branches. With this novel control method, the M3C can effectively overcome the capacitor voltage fluctuation without using balancing techniques based on common mode voltage or applying reactive power at the input side.

This paper presents novel integration options for passive inductor which include: motor-shaped rotational and motor-shaped rotor-less inductor for high speed motor drive system. The novel options have been designed and their performance is compared with the conventional EE core inductor using finite element analysis. It is observed that there is a significant reduction in total losses at fundamental frequency along with substantial reduction in the AC copper loss at 10, 15 and 20 kHz switching frequencies, when the proposed integrated options are utilized. For the motor-shaped rotational inductor, the total losses at fundamental frequency and AC copper loss at different switching frequencies are reduced by 26.1% and 73.8% (at different switching frequencies) respectively. There is a reduction in overall volume by 3.6%, but this comes with 11.7% increase in weight. For the motor-shaped rotor-less inductor, the total losses at fundamental frequency and AC copper loss at different switching frequencies are reduced by 10.4% and 73.8% (at different switching frequencies) respectively. There is a reduction in overall volume by 3.6% but this comes with 6.1% increase in weight. The proposed designs can share the cooling system of the motor thus, eliminating the requirement of separate cooling system.

This paper presents a novel approach to integrate the output filter inductor in permanent magnet synchronous motor (PMSM) drive system. The integrated output filter inductor is based on utilizing the motor magnetics as a filter inductance instead of introducing a separate filter inductor. Thus, eliminating added filter inductor losses and associated weight and volume. The vector controlled model, taking modulation and switching effect in to account, has been developed using MATLAB/Simulink tool for the proposed integrated output filter inductor. The currents obtained from MATLAB/Simulink model are then injected into the Finite Element model to validate the concept. The performance of the proposed and conventional system is analyzed in terms of mean electromagnetic torque, torque ripple, motor losses, inductor losses, weight and volume.

The Future Global Electricity Network is expected to have large integration of renewable generators, and to be widely interconnected. As a consequence, the multi-modular bidirectional AC/AC power conversion architectures will play a major role in improving power flow controllability, power quality and availability. This paper proposes a new power converter topology suitable for AC/AC conversion in medium and high voltage applications, based on the matrix concept. The proposed topology combines the advantages of matrix converters with those of modular converters, providing high modularity and scalability, reduced weight and volume, minimum number of conversion stages and minimum energy storage. Galvanic isolation is provided at medium frequency, reducing size and cost of the transformer. The paper introduces the converter concept and commutation strategy and proposes a modified Venturini modulation in order to provide a per-switching cycle control of the Volt-Second balance across the transformer.

Active Magnetic Bearing (AMB) technology is becoming attractive for several reasons such as high speed operations, high reliability and vibrations exemption. Moreover, AMB can behave as active vibration dampers and provide a real-time control of the shaft. For all these advantages, AMBs are particularly attractive for high power - high speed applications. These desirable features come at the cost of an increased complexity of the system, which now includes a power electronic converter and a control system dedicated to the AMBs. This paper focus on the overall system design, from the AMB design, to the power electronic converter design and control, for an AMB featuring Wheatstone bridge winding configuration. The magnetic design has been developed analytically and validated by means of Finite Elements simulation, to generate up to 2kN of axial forces. The power conversion system is based on three full bridges, one to magnetize the bearing and two to control the axial forces independently on the x and y axes. In order to achieve high bandwidth current control able to generate the desired orthogonal forces, a predictive control strategy has been proposed, for the several advantages it can provides such as fast dynamic response, no need of modulation, easy inclusion of nonlinearities and constraints of the system, possibility of incorporating nested control loops in only one loop and the flexibility to include other system requirements in the controller. The control system has been validated in Matlab/PLECS simulation, including the effect of parameters mismatches in the coils.

The matrix converter current recirculating path during an open circuit condition is given in detail with the aim of contributing more expert knowledge to a fault detection system for matrix converter. Simulation results were obtained demonstrating how current recirculates in the matrix converter and the clamp circuit during an open-circuit fault. Healthy output phase currents can be canceled to zero due to current recirculating via the clamp circuit. This result could contribute expert knowledge to a fault detection system to avoid false fault detection and diagnosis.

Droop control methods are widely used in dc microgrids due to its simplicity and easy implementation. However, DC bus voltage deviation increases as the droop gain increases although accuracy of power sharing is improved. In order to overcome this paper proposes an improved voltage regulation method under high droop gain circumstance with consideration of cable impedance. It allows accurate power sharing and the low voltage-regulation simultaneously. The reduced-order model is developed neglecting fast converter dynamics. The effect of this proposed method on stability is also studied by eigenvalues method. Time domain simulation in Matlab/Simulink validates all the analysis.

In this paper is presented an alternative to generate sinusoidal output voltage waveforms using predictive control in an indirect matrix converter while achieving sinusoidal source currents on the input side. These objectives are accomplished by using a predictive control scheme which calculates the future values of the variables to be controlled in order to choose the converter state that produces the minimal error between them and their references. The proposed predictive method is tested by simulation results, obtaining sinusoidal output voltage and achieving a desired input displacement factor, with a low THD on both source currents and load voltages.

This paper deals with reverse characteristics of normally-off SiC JFET and application of it in matrix converter. Forward and reverse conduction characteristics of SiC JFET are extracted and the demands for driving it are presented. Furthermore, it is employed in 2-phase to 1-phase matrix converter with and without antiparallel SiC diode. Then static and dynamic performances of it are investigated in different conditions to present the influence of eliminating the external diode. The results and methodology provide a useful and practical tool in a SiC power converter design.

With the increasing interest in matrix converter technology, in industrial, aerospace and military applications, it is desirable for these converters to continue to operate in faulty conditions. Albeit with diminished performance in some regard. However for continued operation it is necessary to localise any converter faults quickly and accurately. This paper presents a low frequency modulation table based fault localisation system for matrix converters using Space Vector Modulation (SVM). With the fault detection system implemented as a fuzzy inference system.

Variable-speed diesel generation systems have advantages when compared to fixed-speed generators. For example reduced fuel consumption at some operating points, less maintenance, increased life of the engine because it is operated with a lower thermal signature. Moreover, higher power output can be obtained by operating the diesel engine at high rotational speeds, improving the power to size ratio. A 4-leg matrix converter can be used to feed a stand-alone load or isolated grid, providing a path for the circulation of the zero sequence load current. In this work the control systems appropriate for variable-speed diesel engines feeding a 4-leg matrix converter are discussed. Control systems based on two revolving axes and zero sequence controllers are discussed in this work. Experimental results obtained from a prototype are presented and fully analysed.

This paper investigates some of the challenges encountered during the implementation of a high speed digital control for a Silicon Carbide JFET matrix converter which has been designed to meet a specific power density of 20kW/litre with forced air cooling. After a brief introduction on the main features of the hardware implementation of this unique power converter, an insight into the control strategy and controller platform adopted is given with a particular attention to the performance implications of the gate drive circuitry. Results to show the effect of gate driver and controller induced commutation time limitations on output waveform quality are presented.