A5010726674- Microgrid Control and Optimization
- Power Systems and Renewable Energy
- Multilevel Inverters and Converters
- Advanced DC-DC Converters
- Electric Motor Design and Analysis
- Sensorless Control of Electric Motors
- Power Quality and Harmonics
- Magnetic Bearings and Levitation Dynamics
- Advanced Algorithms and Applications
- Wind Turbine Control Systems
- HVDC Systems and Fault Protection
- Magnetic Properties and Applications
- Industrial Technology and Control Systems
- High-Voltage Power Transmission Systems
- Silicon Carbide Semiconductor Technologies
- Smart Grid and Power Systems
- Advanced Battery Technologies Research
- Islanding Detection in Power Systems
- Electromagnetic Compatibility and Noise Suppression
- Advanced Sensor and Control Systems
- Induction Heating and Inverter Technology
- Frequency Control in Power Systems
- Geomechanics and Mining Engineering
- Fuel Cells and Related Materials
- Industrial Automation and Control Systems
Tsinghua University
2014-2024
Yunnan Normal University
2024
Second Affiliated Hospital of Harbin Medical University
2023
Harbin Medical University
2023
Texas A&M University at Qatar
2014
China University of Mining and Technology
2012
Soochow University
2011
Chengdu Second People's Hospital
2010
Mitsubishi Electric (Japan)
2002
Voltage balance issue of dc-link capacitors is very important for applications a cascade multilevel converter or modular converter. In this paper, novel diode-clamped (DCM <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> C) topology proposed and power feedback control method developed. With the developed strategy, circuit becomes controllable closed loop which enables capacitor voltages to be clamped by low rating clamping diodes. The...
Conventional matrix converters (MCs) have limited voltage gain that is less than 0.866, whether for direct MC (DMC) or indirect (IMC). Existing Z-source (ZS)/discontinuous quasi-Z-source (qZS) DMCs and ZS IMCs achieved larger 0.866 gain; however, the former inherited complex commutation from DMC, latter involved a network in dc link led to non-all-silicon solution. In this paper, discontinuous qZS networks of existing ZS/qZS are used an IMC topology simplifying having high gain, but they...
Background: With the continuous development of permanent magnet synchronous motors (PMSM) and increasing demand for application flywheel battery, requirements PMSMs are also increasing. Methods: A multi-objective genetic algorithm is used to solve optimal design solution Results: Multi-objective fast accurate in calculation results, it easy obtain solution. The results show that cogging torque reduced by 23.6%, ripple 25%, average increased 1.2%. Conclusion: optimization was conducted on a...
Summary A new type of three‐phase quasi‐Z‐source indirect matrix converter (QZS‐IMC) is proposed in this paper. It uses a unique impedance network for achieving voltage‐boost capability and making the input current continuous conduction mode (CCM) to eliminate filter. The complete modulation strategy operate QZS‐IMC. Meanwhile, closed‐loop DC‐link peak voltage control proposed, estimated by measuring both capacitor voltages. With technique, high‐performance output can be achieved with an...
Current therapies cannot completely reverse advanced atherosclerosis. High levels of amino acids, induced by Western diet, stimulate mTORC1 (mammalian target rapamycin complex 1)-autophagy defects in macrophages, accelerating atherosclerotic plaque progression. In addition, autophagy-lysosomal dysfunction contributes to necrotic core enlargement and lipid accumulation. Therefore, it is essential investigate the novel mechanism molecules acid-mTORC1-autophagy signaling macrophages patients with
Purpose – The paper aims to propose a new type of three-phase quasi-Z-source indirect matrix converter (QZSIMC) extend the voltage gain for application in induction motor drives. Design/methodology/approach A unique H-shape network is connected between source and traditional achieve boost buck single-stage power conversion. complete space vector modulation (SVM) method proposed control QZSIMC. output amplitude can be boosted by shoot-through front-end rectifier, so whole system's extended....
Summary Quasi‐Z source indirect matrix converter (IMC) combines both advantages of conventional IMC and quasi‐Z inverter, for example, no direct current (DC) link capacitor, compact all‐silicon power converter, bidirectional flow, input factor controllable, high voltage gain; moreover, it does not require additional filter, because continuous network integrates LC filter function. However, there is literature to disclose common mode (CMV) issue IMC. In this paper, the first time, CMV...
This article aims to propose a highly reliable permanent magnet synchronous machine (PMSM) for flywheel energy-storage systems. Flywheel systems are large-capacity energy storage technologies suitable the short-term of electrical energy. PMSMs have been used in due their advantages. One key requirements is high reliability. A double redundant winding structure adopted ensure fault-tolerant operation PMSM. The stator designed with auxiliary teeth reduce short-circuit current. Moreover, number...
The traditionally matrix converter is a buck AC-AC power conversion and the maximum voltage gain limited to 0.866. paper proposes new indirect quasi-Z-source converter, extend for application in induction motor drives, then operation principle control scheme are clarified. A simulated 4 kW drive carried out. Theoretical calculations feasibility of proposed topology verified. can boost larger than one.
Active Power Filters (APFs) are widely applied devices in the power quality field for control flexibility and effective attenuation of harmonic, reactive negative components grid current voltage. As interface connecting an APF with grid, LCL-filter is preferred over L-filter its smaller size lower price. However, a third-order system hence causes stability problems by resonance phenomenon. To suppress resonances, either active or passive damping methods should be conducted. Passive simple...
The development of micro-grids and renewable energy requires storage systems with larger capacity higher power rating. flywheel array has the advantages simplicity, reasonable cost good scalability, which is suitable for micro-grid large-scale wind farm. In this paper, on one hand, coordinated control strategies in parallel AC bus DC conducted proposed, function between change rate state charge (SOC) by time its value derived. On other needs to avoid over-charge over-discharge, thus it's...
This paper presents a novel position sensor-less method based on Model Reference Adaptive System (MRAS) for the control of Variable Speed Constant Frequency (VSCF) Doubly Fed Induction Generator (DFIG). In this components stator flux in stationary reference coordinates are used both and adjustable models. The model is given by equations with as outputs while rotor to calculate using quantities such currents, flux. order get accurate model, modified integrator has been used. No current...
Conventional matrix converters have a limited voltage gain less than 0.866 and also require many power switches additional input filter that ensures low current harmonics to the grid. Quasi-Z source (qZS) indirect converter can provide high ensure sinusoidal without filter, which requires 12 in rectifier stage. In this paper, simplified qZS is proposed overcome aforementioned limitations achieve (1) higher 0.866, (2) switches, (3) LC-filter function integrated network avoid filter. The new...
A new space vector modulation (SVM) strategy is proposed for quasi-Z-source indirect matrix converter (QZS-IMC) to reduce common-mode voltage and ensure a high transfer ratio. QZS-IMC's analyzed, the subdivided sectors are employed rearrange switching sequence in inverter stage, which can power loss. The method mitigates peak value of by 42% reduces losses stage. Experimental results verify method.
A new calculation method to estimate the power loss and working temperature of IGBT diode devices in an inverter is presented. This based on measurement data IGBT's transient steady state characteristics under different conditions thermal equivalent network model actual system. Finally, experiment a drive system including permanent magnet synchronous motor was done. The result shows that program very effective for design inverters.
Doubly fed induction machine(DFIM) has excellent speed regulation performance, which can meet the demand of frequency and voltage power grid solve problem efficiency reduction pump-turbine resulting from change hydraulic head when applied to pumped storage. To omit drainage process runner chamber before DFIM start-up, a control method soft-starting with slight load is proposed ensures that increases smoothly zero required for gridconnection. The field current compensator rotor position angle...
This paper presents a simplified model predictive control (MPC) method for current of twelve-phase permanent magnet synchronous motor (PMSM). For the PMSM driven by two-level converter, total number switching states is 4096. Even only considering 24 largest voltage vectors, computational burden still heavy. In this paper, vectors are divided into 6 sectors evenly. Assuming that currents equal to reference ones, then can be calculated and located in sectors. Therefore, cost function need...
The junction temperature of IGBT is the key factors that could influence whole system's reliability and efficiency. An electro-thermal method was implemented to estimate devices in this paper. power found out based on losses transient thermal impedance model. comparison between experiment using a 50 A/600 V module calculation results shows effective.
This paper presents a model reference adaptive system (MRAS)-based charging and discharging control method for twelve-phase permanent magnetic synchronous motor (PMSM) in flywheel energy storage (FESS). The proposed speed estimation strategy can make the FESS operate at high regardless of declining precision reliability sensors. Considering mutual coupling among 4 sets three-phase stator windings, compensation is developed to achieve independent sets. Furthermore, combined with strategy,...
This paper proposes a novel hybrid active power filter (HAPF) for 6 kV/10 kV medium-voltage distribution network. Passive (PPF) and small-rated (APF) using diode neutral-point-clamped (NPC) three-level inverter, which is shunted to fundamental resonance circuit (FRC), are directly connected in series without any matching transformer, thus forming the shunt HAPF. Its principle control strategies were discussed. In order decrease tracking error of harmonic compensation current improve dynamic...