A novel detection and localization approach of open-circuit switch fault for the grid-connected modular multilevel converter

IEEE Transactions on Industrial Electronics

Published On 2022/3/1

The open-circuit fault detection and localization (FDL) technique can improve the reliability of the modular multilevel converter (MMC). However, the conventional software-based FDL methods usually have a heavy computation burden or a limited localization speed. This article proposes a simplified and fast software-based FDL approach for the grid-connected MMC. First, the errors between the measured state variables (the output current and the circulating current) and their estimated values are calculated. By comparing these errors with their threshold values, the switch fault can not only be detected but also be localized to the specific arm. Then, the capacitor voltages in this faulty arm are collected, and the submodule (SM) with the highest capacitor voltage is selected. To confirm the switch fault in this SM, a modified Pauta criterion is presented to check the abnormal voltage data. As a result, the computation …

Journal

IEEE Transactions on Industrial Electronics

Published On

2022/3/1

Volume

70

Issue

1

Page

112-124

Authors

Frede Blaabjerg

Frede Blaabjerg

Aalborg Universitet

Position

Professor in Power Electronics Villum Investigator Denmark

H-Index(all)

197

H-Index(since 2020)

136

I-10 Index(all)

0

I-10 Index(since 2020)

0

Citation(all)

0

Citation(since 2020)

0

Cited By

0

Research Interests

Power Electronics

Renewable Energy

Wind Turbines

Power Systems

Electrical Engineering

University Profile Page

Remus Teodorescu

Remus Teodorescu

Aalborg Universitet

Position

Professor at

H-Index(all)

104

H-Index(since 2020)

72

I-10 Index(all)

0

I-10 Index(since 2020)

0

Citation(all)

0

Citation(since 2020)

0

Cited By

0

Research Interests

Power Electronics

Smart Batteries

AI

University Profile Page

Tomislav Dragičević

Tomislav Dragičević

Danmarks Tekniske Universitet

Position

Professor

H-Index(all)

72

H-Index(since 2020)

69

I-10 Index(all)

0

I-10 Index(since 2020)

0

Citation(all)

0

Citation(since 2020)

0

Cited By

0

Research Interests

Microgrids

Electric Drives

Power Electronics

Power Systems

Smart Grids

University Profile Page

Qian Xiao

Qian Xiao

Tianjin University

Position

Assitant Professor

H-Index(all)

15

H-Index(since 2020)

15

I-10 Index(all)

0

I-10 Index(since 2020)

0

Citation(all)

0

Citation(since 2020)

0

Cited By

0

Research Interests

Microgrids

DC Distribution Network

Multilevel Converters

BESS

Energy Router

University Profile Page

Yu Jin

Yu Jin

Harbin Institute of Technology

Position

H-Index(all)

10

H-Index(since 2020)

10

I-10 Index(all)

0

I-10 Index(since 2020)

0

Citation(all)

0

Citation(since 2020)

0

Cited By

0

Research Interests

Multilevel converters

Battery energy storage system

FACTs

University Profile Page

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IEEE Transactions on Industrial Electronics

Constant Current Precharging Algorithm for Solid State Power Controllers

Semiconductor-based solid-state power controllers (SSPCs) are a promising solution for dc system protection. During the connection of capacitive loads there is an inrush current because of zero initial energy in the capacitor, which can cause damage to the system. One of the main challenges of SSPCs is to suppress the current and voltage overshoot during precharging. In most of the precharging methods, additional circuitry is required, which adds weight, size, and complexity to the system. In this article, a constant current precharging algorithm is proposed. The main semiconductor device is utilized for precharging instead of adding an auxiliary circuit, thus reducing the required number of components. In addition, the proposed algorithm has a higher adaptability to the change of system parameters. Moreover, it is easily implementable to a wide range of semiconductor devices. Analytical evaluations are …

Wei Hua (花为)

Wei Hua (花为)

Southeast University

IEEE Transactions on Industrial Electronics

Robust Diagnosis of Partial Demagnetization Fault in PMSMs Using Radial Air-Gap Flux Density Under Complex Working Conditions

Partial demagnetization fault (PDF) is a common problem for permanent magnet synchronous motor (PMSM). The PMSM usually operates under complex working conditions (dynamic speed and various load), leading to the difficulty in robust PDF diagnosis. Hence, how to reliably and accurately diagnose PDF under complex working conditions has become a key issue in ensuring its safe operation. To address this issue, a robust PDF diagnosis method for PMSM is proposed based on radial air-gap flux density in this article. First, the d -axis magnetic network model of PMSM is established to extract the fault feature from the radial air-gap flux density. Then, by subtracting the offline-calculated radial air-gap flux density of stator current excitation from the online measured value, the open-circuit radial air-gap flux density can be calculated. Next, the equiangular interval resampling method is used to obtain the open …

Zhongbao Wei(魏中宝)

Zhongbao Wei(魏中宝)

Beijing Institute of Technology

IEEE Transactions on Industrial Electronics

Cathodic Supply Optimization of PEMFC System Under Variable Altitude

The efficiency of the proton exchange membrane fuel cell (PEMFC) system drops remarkably with the changed ambient pressure and temperature under variable altitudes. To enhance the adaptability of PEMFC, this article proposes a hierarchical optimal control strategy (HOCS) that guarantees the efficient operation of the PEMFC system during changes in altitude. In particular, the sparrow search algorithm (SSA) is exploited to optimize the air supply strategy under different operating conditions. To support the HOCS, a variable altitude model of PEMFC is established, which integrates the environmental impacts on components. A sliding mode controller (SMC) is employed to achieve precise and fast control of the air supply system across various situations. Comparative results validate the superiority of the proposed method in terms of the efficiency of the air compressor and the net power output. In a typical driving …

Tianliang Li

Tianliang Li

National University of Singapore

IEEE Transactions on Industrial Electronics

Modular and Fault-Tolerant Three-Axial FBG-Based Force Sensing for Transoral Surgical Robots

Transoral robotic surgery (TROS) has met a significant challenge to precise control of surgical instruments and depress the injury risks without force feedback. Therefore, we develop a modular high-precision three-axial fiber Bragg grating (FBG) force sensor with nonlinear decoupling, fault tolerance, and temperature compensation (TC) for seamless integration into transoral robots. The sensor comprises a one-body elastomer housing four optical fibers engraved with FBG each, arranged at a constant interval of 90° along the circumference to enhance three-axial force perception through redundancy. A novel dung Beetle optimization extreme learning machine (DBO-ELM) algorithm is proposed to tackle nonlinear coupling, FBG fracture, and temperature interference challenges leading to excellent performances of accurate and reliable measurement. The maximum full-scale error is less than 4% in each dimension …

Chunhua Yang

Chunhua Yang

Central South University

IEEE Transactions on Industrial Electronics

Multimodel Self-Learning Predictive Control Method With Industrial Application

In industrial sites, system operation conditions fluctuate due to changes in raw material and equipment status, making it critical to identify the operation conditions and obtain appropriate controllers accurately. Additionally, even for a specific operation condition, fixed control strategies may result in mismatches due to varying operational stages. To address the accurate control of industrial processes across multiple operation conditions, this article proposes a multimodel self-learning predictive control (MSLPC) method to simultaneously improve the accuracy of offline condition partition and online control performance. Specifically, in the offline stage, for complex and multidimensional industrial data, condition indicators are selected based on expert systems and data analytics, and a “presetting precise-fusion” two-stage operation condition learning (TSOCL) algorithm is proposed to accurately identify the operation …

Choon Ki Ahn

Choon Ki Ahn

Korea University

IEEE Transactions on Industrial Electronics

Model-Free Filter-Based Single-Loop Output-Feedback System Design for PMSMs With Critically Damped Performance

This article designs a filter-based output-feedback system to regulate the speed of permanent magnet synchronous motors (PMSMs), which structures a simple single-loop form compensated by feed-forward terms. The proposed controller design framework considerably reduces the dependence level of the PMSM model by requiring partial nominal parameter values for control law and removing the model structure and whole parameter information for the filter. The main advantages consist of two parts. First, the proposed observer employs the second-order pole-zero cancelation (PZC) technique to continuously extract the speed and acceleration from noisy position measurements by the rotary encoder, independent from the PMSM model. Second, the PZC filter-based proportional–integral control forms a single-loop feedback system including the active damping injection and disturbance observer, which assigns …

Sang-Won Lee

Sang-Won Lee

Kongju National University

IEEE Transactions on Industrial Electronics

Quasi-Resonant Fly-Buck Converter With Active Switching for Improved Output Voltage Boosting and Regulation

This article proposes a quasi-resonant fly-buck converter using an active switching operation at the isolated load side. The proposed circuit overcomes the cross-regulation and low voltage gain problems of the conventional fly-buck converter with the simple quasi-resonance operation between the inherent leakage inductance of a transformer and an auxiliary capacitor at the isolated secondary side. The converter implements the high step-up operation using an auxiliary switch; therefore, the reduced winding ratio of the transformer improves the power density of the circuit. In addition, this circuit implements the soft switching at all active components, and does not suffer from the reverse recovery problem at a diode. A 20 W prototype having an input voltage of 12 V was built to prove the theoretical analyses, and it regulated 5 V for 10 W and 15 V for 10 W at the primary nonisolated and secondary isolated load sides …

Xiaoshan Bai

Xiaoshan Bai

Technische Universiteit Delft

IEEE Transactions on Industrial Electronics

Efficient Performance Impact Algorithms for Multirobot Task Assignment With Deadlines

This article investigates the multirobot task assignment problem with deadlines, where a group of distributed heterogeneous robots needs to collaborate effectively to first maximize the number of successful search and rescue missions and then minimize the robots' total service time. First, a distributed performance impact algorithm is designed to obtain the initial assignment solution, where each robot can compute its assignment solution independently. Subsequently, based on different local search strategies, a disturbance mechanism and two improvement strategies, namely, first, global task inclusion first and decoupled 1-opt second phase and, second, global task inclusion first and coupled 1-opt second phase, are proposed to disrupt and refine the initial solution. The integration of the distributed performance impact algorithm with the two refinement strategies leads to a decoupled performance impact algorithm …

zhiliang zhang

zhiliang zhang

Nanjing University of Aeronautics and Astronautics

IEEE Transactions on Industrial Electronics

Digital Synchronous Rectifier Control Using Extended Harmonics Impedance Model for High-Frequency GaN-Based LLC Converters

Conventional LLC synchronous rectifier (SR) schemes use detection circuits to sense the signals of voltage or current. But it typically operates below 500 kHz, which is unsuitable for high-frequency applications as it may lose large SR duty cycle caused by high dv/dt and GaN devices usage. To address the serious challenge, a digital SR control using extended harmonics impedance model is proposed for GaN LLC converters. By building the impedance model, the SR on-time is calculated accurately in the microcontroller. It not only minimizes the on-time of SR body diode with high precision, but also owns high immunity. A 650-kHz 1.5-kW GaN LLC converter was built. With the output of 28 V/53.5 A, the efficiency is as high as 98.1% at 1.5 kW by using the proposed SR. The power density is also up to 524 W/in 3 . Compared to the conventional SR, the efficiency improves 1.6% at full load.