Optimal Nonlinear Adaptive Control for Voltage Source Converters via Memetic Salp Swarm Algorithm: Design and Hardware Implementation

Voltage source converter (VSC) has been extensively applied in renewable energy systems which can rapidly regulate the active and reactive power. This paper aims at developing a novel optimal nonlinear adaptive control (ONAC) scheme to control VSC in both rectifier mode and inverter mode. Firstly, the nonlinearities, parameter uncertainties, time-varying external disturbances, and unmodelled dynamics can be aggregated into a perturbation, which is then estimated by an extended state observer (ESO) called high-gain perturbation observer (HGPO) online. Moreover, the estimated perturbation will be fully compensated through state feedback. Besides, the observer gains and controller gains are optimally tuned by a recent emerging biology-based memetic salp swarm algorithm (MSSA), the utilization of such method can ensure a desirably satisfactory control performance. The advantage of ONAC is that even though the operation conditions are constantly changing, the control performance can still be maintained to be globally consistent. In addition, it is noteworthy that in rectifier mode only the reactive power and DC voltage are required to be measured, while in inverter mode merely the reactive power and active power have to be measured. At last, in order to verify the feasibility of ONAC in practical application, a hardware experiment is implemented.

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Fault Ride-Through Capability Enhancement of Type-4 WECS in Offshore Wind Farm via Nonlinear Adaptive Control of VSC-HVDC

Processes ◽

10.3390/pr7080540 ◽

2019 ◽

Vol 7 (8) ◽

pp. 540 ◽

Cited By ~ 2

Author(s):

Yiyan Sang ◽

Bo Yang ◽

Hongchun Shu ◽

Na An ◽

Fang Zeng ◽

...

Keyword(s):

Adaptive Control ◽

Power Plants ◽

Wind Farms ◽

Offshore Wind ◽

Voltage Source ◽

Time Varying ◽

Parameter Uncertainties ◽

Model Uncertainties ◽

Nonlinear Adaptive Control ◽

Fault Ride Through

This paper proposes a perturbation estimation-based nonlinear adaptive control (NAC) for a voltage-source converter-based high voltage direct current (VSC-HVDC) system which is applied to interconnect offshore large-scale wind farms to the onshore main grid in order to enhance the fault ride-through (FRT) capability of Type-4 wind energy conversion systems (WECS). The VSC-HVDC power transmission system is regraded as a favourable solution for interconnecting offshore wind farms. To improve the FRT capability of offshore power plants, a de-loading strategy is investigated with novel advanced control of the VSC-HVDC systems. The proposed NAC does not require an accurate and precise model and full state measurements since the combinatorial effects of nonlinearities, system parameter uncertainties, and external disturbances are aggregated into a perturbation term, which are estimated by a high-gain perturbation observer (HGPO) and fully compensated for. As the proposed NAC is adaptive to system model uncertainties (e.g., mismatched output impedance of the converters and the line impedance of transmission line), time-varying disturbance (e.g., AC grid voltage sags and line to ground faults), and unknown time-varying nonlinearities of the power-electronic system (e.g., unmodelled dynamics existed in valve and VSC phase-locked loop system), a significant robustness can be provided by the de-loading strategy to enhance the FRT capability. Simulation results illustrated that the proposed strategy can provide improved dynamic performance in the case of operation with a variety of reduced voltage levels and improved robustness against model uncertainties and mismatched system parameters comparing with conventional vector control.

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Distribution system power quality compensation using a HSeAPF based on SRF and SMC features

International Journal of Systems Assurance Engineering and Management ◽

10.1007/s13198-021-01185-w ◽

2021 ◽

Author(s):

Akram Qashou ◽

Sufian Yousef ◽

Abdallah A. Smadi ◽

Amani A. AlOmari

Keyword(s):

Power Distribution ◽

Distribution System ◽

Reactive Power ◽

Sliding Mode ◽

Distribution Network ◽

Harmonic Distortion ◽

Phase Locked Loop ◽

Voltage Source ◽

Voltage Source Converter ◽

Non Linear

AbstractThe purpose of this paper is to describe the design of a Hybrid Series Active Power Filter (HSeAPF) system to improve the quality of power on three-phase power distribution grids. The system controls are comprise of Pulse Width Modulation (PWM) based on the Synchronous Reference Frame (SRF) theory, and supported by Phase Locked Loop (PLL) for generating the switching pulses to control a Voltage Source Converter (VSC). The DC link voltage is controlled by Non-Linear Sliding Mode Control (SMC) for faster response and to ensure that it is maintained at a constant value. When this voltage is compared with Proportional Integral (PI), then the improvements made can be shown. The function of HSeAPF control is to eliminate voltage fluctuations, voltage swell/sag, and prevent voltage/current harmonics are produced by both non-linear loads and small inverters connected to the distribution network. A digital Phase Locked Loop that generates frequencies and an oscillating phase-locked output signal controls the voltage. The results from the simulation indicate that the HSeAPF can effectively suppress the dynamic and harmonic reactive power compensation system. Also, the distribution network has a low Total Harmonic Distortion (< 5%), demonstrating that the designed system is efficient, which is an essential requirement when it comes to the IEEE-519 and IEC 61,000–3-6 standards.

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A Novel Adaptive Control Approach Based on Available Headroom of the VSC-HVDC for Enhancement of the AC Voltage Stability

Energies ◽

10.3390/en14113222 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3222

Author(s):

Duc Nguyen Huu

Keyword(s):

Adaptive Control ◽

Voltage Stability ◽

Reactive Power ◽

Control Method ◽

Offshore Wind ◽

Voltage Source ◽

Long Distance ◽

Control Approach ◽

Hvdc System ◽

Voltage Support

Increasing offshore wind farms are rapidly installed and planned. However, this will pose a bottle neck challenge for long-distance transmission as well as inherent variation of their generating power outputs to the existing AC grid. VSC-HVDC links could be an effective and flexible method for this issue. With the growing use of voltage source converter high-voltage direct current (VSC-HVDC) technology, the hybrid VSC-HVDC and AC system will be a next-generation transmission network. This paper analyzes the contribution of the multi VSC-HVDC system on the AC voltage stability of the hybrid system. A key contribution of this research is proposing a novel adaptive control approach of the VSC-HVDC as a so-called dynamic reactive power booster to enhance the voltage stability of the AC system. The core idea is that the novel control system is automatically providing a reactive current based on dynamic frequency of the AC system to maximal AC voltage support. Based on the analysis, an adaptive control method applied to the multi VSC-HVDC system is proposed to realize maximum capacity of VSC for reactive power according to the change of the system frequency during severe faults of the AC grid. A representative hybrid AC-DC network based on Germany is developed. Detailed modeling of the hybrid AC-DC network and its proposed control is derived in PSCAD software. PSCAD simulation results and analysis verify the effective performance of this novel adaptive control of VSC-HVDC for voltage support. Thanks to this control scheme, the hybrid AC-DC network can avoid circumstances that lead to voltage instability.

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Adaptive Control for Voltage Source Converter Connected to Weak Grid Based on Backstepping Method

2020 IEEE 9th Power India International Conference (PIICON) ◽

10.1109/piicon49524.2020.9112923 ◽

2020 ◽

Author(s):

Pritha Paitandy ◽

Surya Prakash ◽

Sukumar Mishra

Keyword(s):

Adaptive Control ◽

Voltage Source ◽

Voltage Source Converter ◽

Backstepping Method ◽

Weak Grid ◽

Grid Based

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Adaptive SRF-PLL Based Voltage and Frequency Control of Hybrid Standalone WECS with PMSG-BESS

International Journal of Emerging Electric Power Systems ◽

10.1515/ijeeps-2018-0072 ◽

2018 ◽

Vol 19 (6) ◽

Cited By ~ 1

Author(s):

Anjana Jain ◽

R. Saravanakumar ◽

S. Shankar ◽

V. Vanitha

Keyword(s):

Reactive Power ◽

Frequency Control ◽

Storage System ◽

Synchronous Generator ◽

Energy Storage System ◽

Voltage Regulation ◽

Operating Conditions ◽

Voltage Source ◽

Voltage Source Converter ◽

Control Scheme

Abstract The variable-speed Permanent Magnet Synchronous Generator (PMSG) based Wind Energy Conversion System (WECS) attracts the maximum power from wind, but voltage-regulation and frequency-control of the system in standalone operation is a challenging task A modern-control-based-tracking of power from wind for its best utilization is proposed in this paper for standalone PMSG based hybrid-WECS comprising Battery Energy Storage System (BESS). An Adaptive Synchronous Reference Frame Phase-Locked-Loop (SRF-PLL) based control scheme for load side bi-directional voltage source converter (VSC) is presented for the system. MATLAB/Simulink model is developed for simulation study for the proposed system and the effectiveness of the controller for bi-directional-converter is discussed under different operating conditions: like variable wind-velocity, sudden load variation, and load unbalancing. Converter control scheme enhances the power smoothening, supply-load power-matching. Also it is able to regulate the active & reactive power from PMSG-BESS hybrid system with control of fluctuations in voltage & frequency with respect to varying operating conditions. Proposed controller successfully offers reactive-power-compensation, harmonics-reduction, and power-balancing. The proposed scheme is based on proportional & integral (PI) controller. Also system is experimentally validated in the laboratory-environment and results are presented here.

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Adaptive Control Scheme for Grid Tied SPV System with DSTATCOM Capabilities: Review

Journal of University of Shanghai for Science and Technology ◽

10.51201/jusst/21/07195 ◽

2021 ◽

Vol 23 (07) ◽

pp. 678-689

Author(s):

Bilal Ahmad Ganie ◽

◽

Dr. (Mrs.) Lini Mathew ◽

Keyword(s):

Adaptive Control ◽

Stage Structure ◽

Voltage Regulation ◽

Control Technique ◽

Voltage Source ◽

Voltage Source Converter ◽

Current Harmonics ◽

Control Approach ◽

Photovoltaic Array ◽

Static Compensator

This study provides an adaptive control approach of VSC (voltage source converter) coupled with SPV (solar photovoltaic array), in a 3P3W (three-phase three-wire) system with three single-phase non-linear loads having Distributed Static Compensator (DSTATCOM) abilities using P and O (perturb & observe) methodology. The adaptive control technique converges quickly and has a low mean square error. For the correction of power factor and zero voltage regulation modes, the system is studied and simulated. The system’s great efficacy at high voltages is due to its one-stage structure. Grid current harmonics are significantly below the IEEE-519 norm. The suggested system is modeled and simulated with the available sim power system toolbox in MATLAB/Simulink, and the system’s behavior under different loads and environmental circumstances is confirmed.

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Research on Serial VSC-LCC Hybrid HVdc Control Strategy and Filter Design Scheme

Energies ◽

10.3390/en13092260 ◽

2020 ◽

Vol 13 (9) ◽

pp. 2260

Author(s):

Fan Cheng ◽

Lijun Xie ◽

Zhibing Wang

Keyword(s):

Reactive Power ◽

Filter Design ◽

Control Strategies ◽

Short Circuit ◽

Voltage Source ◽

Voltage Source Converter ◽

Level Control ◽

Hvdc System ◽

High Voltage Direct Current ◽

Design Scheme

This paper investigated the characteristics of a novel type of hybrid high voltage direct current (HVdc) converter, which is composed by line commutated converter series with voltage source converter. The system and valve level control strategies are introduced, which can provide ac system voltage support. A novel filter design scheme composed by resonant filers for hybrid HVdc are also proposed, which can decrease the capacity of reactive power compensation equipment without deteriorate harmonic characteristics. The ac voltage of HVdc fluctuation level caused by transmitted power variation will be effectively reduced, with the coordination between filter design scheme and converter control. In addition, the influence of ac grid strength is also analyzed by equivalent source internal impedance represented by short circuit ratio (SCR). Finally, the +800 kV/1600 MW hybrid HVdc system connecting two ac grids under different SCR cases are studied, and the PSCAD/EMTDC simulation results have validated the effectiveness for proposed strategy.

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Solar PV Based Shunt Active Filter with p-q Theory Control for Improvement of Power Quality

Journal of Circuits System and Computers ◽

10.1142/s021812661750133x ◽

2017 ◽

Vol 26 (09) ◽

pp. 1750133 ◽

Cited By ~ 3

Author(s):

R. Balamurugan ◽

R. Nithya

Keyword(s):

Fuzzy Logic Controller ◽

Reactive Power ◽

Salient Feature ◽

Voltage Source ◽

Voltage Source Converter ◽

Solar Pv ◽

Pv System ◽

Shunt Active Power Filter ◽

Shunt Active Filter ◽

Point Of Common Coupling

In this paper, fuzzy logic controller (FLC)-based three-phase shunt active power filter with photovoltaic (PV) system is proposed. This filter comprises voltage source converter (VSC) with DC link capacitor at the input side and is supplied by PV system. The salient feature of the filter is that it provides reactive power compensation with line current harmonic reduction and also neutral compensation at point of common coupling (PCC). The PV system and a battery are connected with VSC through DC–DC converter. This paper also proposes a control algorithm using instantaneous [Formula: see text]-[Formula: see text] theory that generates a reference current to counteract the harmonics. The FLC controls the DC link voltage in reference to the above reference current. The performance of the proposed filter for compensation is confirmed by using the MATLAB/Simulink environment and results are validated.

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L-Index Modulated Voltage Source Converter

International Journal of Emerging Electric Power Systems ◽

10.2202/1553-779x.1986 ◽

2008 ◽

Vol 9 (5) ◽

Author(s):

Damian O Dike ◽

Satish M Mahajan

Keyword(s):

Power System ◽

Reactive Power ◽

Reactive Power Compensation ◽

Voltage Source ◽

Voltage Source Converter ◽

Flexible Ac Transmission ◽

Self Tuning ◽

Modulation Signal ◽

Status Indicator ◽

Ac Transmission

A strategy is presented for the self-tuning of a voltage source converter (VSC) based Flexible AC Transmission Systems (FACTS) according to the prevailing system condition. L-index, which is a power system voltage stability status indicator, and its associated parameters are used to automatically regulate the modulation signal of the VSC. This will lead to a proportionate adjusting of the magnitude of the current injected into, or absorbed from, the interconnected load bus by the FACTS device. This regulating scheme will enhance seamless and optimal reactive power compensation by utilizing the dynamic operational nature of present day distressed power system networks. Results obtained using this method when applied to selected load buses of the IEEE 14 bus system under varying practical scenarios showed its capability to appropriately control FACTS devices operation to accommodate system changing conditions. It is hoped that the outcome of this work will provide efficient tools for the determination of power system status, ensure optimal utilization of the dynamic reactive power compensation devices and reduce system outages.

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