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Author

Shuyue Lin

Bio: Shuyue Lin is an academic researcher from University of Warwick. The author has contributed to research in topics: Control theory (sociology) & Turbine. The author has an hindex of 2, co-authored 3 publications receiving 13 citations.

Papers
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Journal ArticleDOI
TL;DR: In this paper , a Gaussian distribution-based inertial control (GDBIC) scheme was proposed to improve the frequency nadir without rotor speed over-deceleration.
Abstract: Accordingto recent grid codes, large-scale wind turbines (WTs) are required to provide fast frequency response (FFR). The existing stepwise inertial control methods suggest immediate incremental power injection by WTs, followed by the abrupt over-production termination to avoid over-deceleration of the rotor speed. These methods have a drawback that they impose severe secondary frequency drops (SFD), or they consider an unrealistic constant wind speed during their inertial control support. This paper proposes a novel Gaussian distribution-based inertial control (GDBIC) scheme that can improve the frequency nadir without rotor speed over-deceleration. Upon detecting a power imbalance, WT increases the output power with an incremental power and declines it following Gaussian distribution trajectory controlled by a standard deviation parameter, ensuring by this convergence of the rotor speed to a stable equilibrium. The proposed scheme is also capable of responding to a second cascade event. The performance of the GDBIC is tested on the wind-integrated IEEE 9-bus system and the IEEE 39-bus system in DIgSILENT PowerFactory. It is also compared with other methods reported in literature. Furthermore, experimental tests are used to verify the performance of the proposed scheme, using two different hardware-in-the-loop testing facilities. The blade fatigue is studied using Fatigue, Aerodynamics, Structures, and Turbulence (FAST) Code. The simulation and experimental results showed that the release of the kinetic energy in rotors using the proposed GDBIC scheme allows significant improvement of the frequency nadir, with no SFD, as well as contribute to reliable operation during abrupt wind changes.

11 citations

Journal ArticleDOI
TL;DR: This work designs an MFAC torque controller to regulate the pump torque of the HWT and compared to an H_inf torque controller and shows better rotor speed stabilisation performance in comparison with the gain-scheduling PI controller and PIAW.
Abstract: The hydrostatic wind turbine (HWT) is a type of wind turbine that uses hydrostatic transmission (HST) drivetrain to replace the traditional gearbox drivetrain. Without the fragile and expensive gearbox and power converters, HWT can potentially reduce the maintenance costs owing to the gearbox and power converter failures in wind power system, especially in offshore cases. We design an MFAC torque controller to regulate the pump torque of the HWT and compared to an H_inf torque controller. Then we design an MFAC pitch controller to stabilise the rotor speed of HWT and compared to a gain-scheduling proportional-integral (PI) controller and a gain-scheduling PI controller with anti-windup (PIAW). The results indicate that MFAC torque controller provides more effective tracking performance than the H_inf controller, and that MFAC pitch controller shows better rotor speed stabilisation performance in comparison with the gain-scheduling PI controller and PIAW.

9 citations

Proceedings ArticleDOI
01 Nov 2016
TL;DR: In this article, a new control algorithm for the virtual infinite capacitor (VIC) is proposed, which is based on a voltage control loop designed for the average model of the converter working in discontinuous conduction mode (DCM).
Abstract: In this paper, we provide a new control algorithm for the virtual infinite capacitor (VIC), which is based on a voltage control loop designed for the average model of the converter working in discontinuous conduction mode (DCM). The voltage controller generates a current reference which is used to generate the gate pulses for the switches via nonlinear open-loop control. The DCM operation combined with some simple improvements to the circuit allow the converter to be operated with soft switching (zero current or zero voltage switching). As a result, we obtain a VIC that operates at much lower switching frequency than was possible before, with very high precision of the voltage regulation, low ripple voltage and low power losses. We demonstrate the usefulness of this VIC as the filter capacitor of the two-phase interleaved power factor compensator (PFC). Our application example is a 230V AC grid connected PFC with an output voltage of 390V DC, feeding a 475W load. We achieve outstanding voltage smoothing performance with a constant switching frequency of 50kHz, significantly lower than what was used in [1], [2].

9 citations

Journal ArticleDOI
01 Oct 2022
TL;DR: In this paper , a faulty feeder detection method based on the characteristics of transient zero-mode current (TZMC) in multi-frequency bands is proposed, which is tested through simulations on the PSCAD/EMTDC platform.
Abstract: In a small-current grounding system, the pole-to-ground fault may cause the voltage drop in the fault pole and the voltage rise in the other poles. In flexible DC distribution systems, Severe voltage variation may shorten the insulation lifetime of the equipment, which leads to great concerns on the safety issue. In addition, the existence of high transition resistance degrades the accuracy of fault detection methods, thus further affecting the reliability of the system. Therefore, it is essential to explore an advanced technology for faulty feeder detection. This study proposes a faulty feeder detection method based on the characteristics of transient zero-mode current (TZMC) in multi-frequency bands. The change rate of zero-mode voltage is applied as the protection activation criterion. Then, the characteristic matrix is constructed via computing the fuzzy entropy of TZMC in each frequency band. Finally, the faulty feeder can be identified by conducting fuzzy C-means on the characteristic matrix. This proposed method is tested through simulations on the PSCAD/EMTDC platform, which successfully demonstrates its outstanding adaptability, reliability, and accuracy.

4 citations

Journal ArticleDOI
TL;DR: In this paper , a decentralized fault section location method is proposed, which is implemented by the primary and secondary fusion intelligent switch (PSFIS) with two preloaded algorithms: autoencoder (AE) and backpropagation neural network.
Abstract: In industrial applications, the existing fault location methods of resonant grounding distribution systems suffer from low accuracy due to excessive dependence on communication, lack of field data, difficulty in artificial feature extraction and threshold setting, etc. To address these problems, this study proposes a decentralized fault section location method, which is implemented by the primary and secondary fusion intelligent switch (PSFIS) with two preloaded algorithms: autoencoder (AE) and backpropagation neural network. The relation between the transient zero-sequence current and the derivative of the transient zero-sequence voltage in each section is analyzed, and its features are extracted adaptively by using AE, without acquiring network parameters or setting thresholds. The current and voltage data are processed locally at PSFISs throughout the whole procedure, making it is insusceptible to communication failure or delay. The feasibility and effectiveness of the approach are investigated in PSCAD/EMTDC and real-time digital simulation system, which is then validated by field data. Compared with other methods, the experiment results indicate that the proposed method performs well in various scenarios with strong robustness to harsh on-site environment and roughness of data.

2 citations


Cited by
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Journal ArticleDOI
TL;DR: In this paper , an indirect adaptive iterative learning control (iAILC) scheme is proposed for both linear and nonlinear systems to enhance the P-type controller by learning from set points.
Abstract: In this article, an indirect adaptive iterative learning control (iAILC) scheme is proposed for both linear and nonlinear systems to enhance the P-type controller by learning from set points. An adaptive mechanism is included in the iAILC method to regulate the learning gain using input–output measurements in real time. An iAILC method is first designed for linear systems to improve control performance by fully utilizing model information if such a linear model is known exactly. Then, an iterative dynamic linearization (IDL)-based iAILC is proposed for a nonlinear nonaffine system, whose model is completely unknown. The IDL technique is employed to deal with the strong nonlinearity and nonaffine structure of the systems such that a linear data model can be attained consequently for the algorithm design and performance analysis. The convergence of the developed iAILC schemes is proved rigorously, where contraction mapping, two-dimensional (2-D) Roesser’s system theory, and mathematical induction are employed as the basic analysis tools. Simulation studies are provided to verify the developed theoretical results.

31 citations

Journal ArticleDOI
TL;DR: In this paper , an indirect adaptive iterative learning control (iAILC) scheme is proposed for both linear and nonlinear systems to enhance the P-type controller by learning from set points.
Abstract: In this article, an indirect adaptive iterative learning control (iAILC) scheme is proposed for both linear and nonlinear systems to enhance the P-type controller by learning from set points. An adaptive mechanism is included in the iAILC method to regulate the learning gain using input–output measurements in real time. An iAILC method is first designed for linear systems to improve control performance by fully utilizing model information if such a linear model is known exactly. Then, an iterative dynamic linearization (IDL)-based iAILC is proposed for a nonlinear nonaffine system, whose model is completely unknown. The IDL technique is employed to deal with the strong nonlinearity and nonaffine structure of the systems such that a linear data model can be attained consequently for the algorithm design and performance analysis. The convergence of the developed iAILC schemes is proved rigorously, where contraction mapping, two-dimensional (2-D) Roesser’s system theory, and mathematical induction are employed as the basic analysis tools. Simulation studies are provided to verify the developed theoretical results.

19 citations

Journal ArticleDOI
TL;DR: This active capacitor can replace large, expensive, and unreliable electrolytic capacitors connected on a dc bus for power filtering and can deal with a wide frequency band of harmonics so that it does not need a priori knowledge of the ripple frequencies.
Abstract: We propose an indirect approach to control an active capacitor, realized using a bidirectional converter, meant for dc voltage filtering (ripple elimination). This active capacitor can replace large, expensive, and unreliable electrolytic capacitors connected on a dc bus for power filtering. It can deal with a wide frequency band of harmonics so that it does not need a priori knowledge of the ripple frequencies. Thanks to the simple decentralized controller proposed in this paper, our active capacitor can be connected directly to the dc bus like a passive filtering capacitor, and no extra connections are needed. Compared with the various direct approaches, a unique feature of the proposed indirect approach is that the buffering capacitor energy $V_{S}^{2}$ is directly regulated and much better dynamics of $V_{S}^{2}$ under sudden load variations are obtained. The control algorithm has been verified by both simulation and experiments, with our circuit being connected to a 350-W commercial power factor compensator.

12 citations

Journal ArticleDOI
TL;DR: A plug-and-play (PnP) realization of the virtual infinite capacitor, which can be connected directly to the dc bus like a passive capacitor without any extra connections, and how to achieve the strictly positive-real property of the overall dc bus by a careful choice of controllers and filters is discussed.
Abstract: The virtual infinite capacitor (VIC) is a nonlinear active capacitor for dc voltage filtering (ripple elimination). It can replace large and unreliable electrolytic capacitors, and it is intended for dc systems where random fluctuations of the dc bus voltage may occur. We propose a plug-and-play (PnP) realization of the VIC, which can be connected directly to the dc bus like a passive capacitor without any extra connections. The proposed control algorithm automatically adjusts the reference voltage of the VIC so that it will be equal to the equilibrium voltage of the dc bus. For the stability of complex interconnected systems, it is recommended that the impedance of the components should be strictly positive real. By studying the output impedance of PnP VIC, we discuss how to achieve the strictly positive-real property of the overall dc bus by a careful choice of controllers and filters. The results were tested by simulations and experiments on a circuit comprising a commercial power factor compensator with an average of 390 V output and a variable resistive load (up to 345 W).

9 citations

Proceedings ArticleDOI
01 Oct 2017
TL;DR: The flying capacitor multilevel converter (FCMC) with one switched-capacitor cell under asymmetric working condition is evaluated, as a highly efficient hardware realization for the virtual infinite capacitor (VIC).
Abstract: We evaluate the flying capacitor multilevel converter (FCMC) with one switched-capacitor cell under asymmetric working condition, as a highly efficient hardware realization for the virtual infinite capacitor (VIC). The VIC is a type of electronic circuit, recently introduced to replace large, expensive and unreliable electrolytic capacitors, mainly intended for smoothing random fluctuations of a DC bus voltage V. By the proposed novel control algorithm, the pulsating power that the VIC takes away from the DC bus is shared among the main buffering and the flying capacitors, with the proportion set by a prescribed value. This facilitates to reduce the physical size of the converter, and hence achieve higher power density. This flying capacitor converter operates in an unconventional way, as the flying capacitor voltage is highly variable and hence the converter works under an asymmetric scenario. An average model of this specific working mode is presented, with the design of a linearized current controller. To improve the capacitance reduction ratio, the average value the of flying capacitor voltage is regulated to a relatively high value, instead of V/2. This is achieved by adjusting the phase shift of the PWM carriers. Both continuous and discontinuous conduction modes are investigated, and verified by simulation.

8 citations