Speed Permanent Magnet Synchronous Generator Research Articles

Adaptive neuro fuzzy technology to enhance PID performances within VCA for grid-connected wind system under nonlinear behaviors: FPGA hardware implementation

Wind Energy Conversion Systems (WECSs) exhibit nonlinear behavior due to internal and external disturbances, which can significantly impact the control performance. Firstly, this paper proposes a Vector Control Approach (VCA) based on Adaptive Neuro Fuzzy (ANF) of Proportional Integral Derivative (PID) controllers for a variable speed Permanent Magnet Synchronous Generator (PMSG)-based WECS connected to the grid to address these issues. The proposed ANF-PID controller combines the robustness of the fuzzy logic with the neural network's performance to ensure high accuracy, excellent tracking, and robustness against the WECS's nonlinear behavior. The neural network automates the placement of fuzzy logic membership functions. Secondly, this paper suggests a real-time hardware implementation of the VCA based on ANF-PID using a Field Programmable Gate Array (FPGA) to reduce the processing time and the WECS's sampling period. The effectiveness of the VCA based on ANF-PID controllers is validated by conducting a numerical simulation within the Matlab-Simulink using the Xilinx System Generator tool, alongside an experimental in-the-loop hardware implementation using FPGA board. Different scenarios are conducted to validate the robustness and stability of the proposed VCA based on ANF-PID control schemes, which is compared to Conventional Fuzzy PID (C-FPID) and PID controllers. The results exhibit that the VCA based on ANF-PID controllers outperforms VCA-C-FPID and VCA-PID controllers in terms of precision, tracking accuracy, and robustness against the WECS's nonlinear behavior and the PMSG parameter variations. The performances of the proposed controllers are tested under some criteria. In fact, the proposed ANF-PID controller provides a Mean Absolute Error (MAE), a Mean Squared Error (MSE) and a Root Mean Squared Error (RMSE) of 8.1911 × 10−04, 8.4181 × 10−05 and 0.0092, respectively. Compared to the C-FPID controller, the proposed controller offers an improvement gain of 98.96 %, 99.61 %, and 93.79 % of MAE, MSE, and RMSE, respectively. When compared to the PID controller, its improvement is even more significant, with a reduction of 99.9919 %, 99.9999 %, and 99.9288 % of MAE, MSE, and RMSE, respectively. In addition, the ANF-PID-based VCA utilizes hardware resources on the FPGA efficiently, requiring only 65.60 % slices LUT, 0.28 % LUTRAM, and 22.99 % FF. This makes it a more cost-effective option compared to the VCA-C-FPID controller for diverse control systems.

Hardware-in-the-loop testing of grid-tied PMSG-based wind power generation system with optimum PI parameters

The regulators based on PI control law continue to be the key elements in many of the industrial systems for their control. Likewise, the wind power generation systems (WPGSs) also make extensive use of PI regulators in their control schemes. The enhanced performance of these WPGS depends on proper selection of the PI regulator parameters. This paper deals with the control of a grid-tied permanent magnet synchronous generator (PMSG)-based WPGS wherein, a new attempt has been depicted to apply the most optimum design of the involved PI regulator parameters for the proposed WPGS based on standard performance indices making use of four popular optimization algorithms namely genetic algorithm (GA), cultural algorithm (CA), particle swarm optimization (PSO) and artificial bee colony (ABC). An informative discussion has also been presented which would be useful for practicing engineers/researchers to select flexibly and reasonably the PI regulators parameters meant for the control of the proposed WPGS. A detailed simulation model developed in MATLAB/Simulink has been used to analyze the performance of the proposed PMSG-based WPGS employed with the most optimum values of PI regulator parameters. The performances of WPGS have been compared while the most optimum PI regulator parameters have been included in the control system, and also when incorporating the PI regulator parameters in WPGS control designed via classical d-partition technique. The results obtained under gradually changing wind speed profile show the improvement in the performance of WPGS in terms of peak overshoot, time response and waveform oscillations. The experimental validation of the control performances have been carried out by way of real-time hardware-in-the-loop (HIL) testing making use of Typhoon HIL402 emulator and TMS320F28335 digital signal controller. The obtained real time HIL results are in close agreement to the results obtained in simulations using MATLAB/Simulink. A deviation of less than 4% was observed in the percentage overshoot/undershoot of the PMSG speed and DC link voltage determined through simulation and experimental means under various wind speed conditions.

Stability Analysis of Active Front End and Permanent Magnet Synchronous Generator With Back EMF-Based Sensorless Control for DC Marine Vessels

This article studies the influence of sensorless control on the permanent magnet synchronous generator (PMSG) and pulsewidth modulation (PWM) converter (active front end rectifier, AFE) system for dc marine vessels. Back EMF-based sensorless control is adopted in this article because the minimum speed of PMSG in a dc marine vessel is enough for obtaining a sufficient back EMF signal. First, the output impedance of “PMSG+AFE” system with a typical topology and controller is deduced by small-signal analysis. The stability analysis with constant power load (CPL) is analyzed, including the influence of sensorless control bandwidth on PMSG with a significant per-unit impedance value. Since the inductance parameter affects both the current control and sensorless control, the influence of error in the estimated inductance parameter on the stability of “PMSG+AFE” system is analyzed. To verify the proposed impedance model, output impedance is measured in the simulation and experiment. The stability analysis with the proposed impedance model and load impedance of CPL is provided in MATLAB, and simulation results and experimental measurements are given to verify the analysis.

Enhancing Grid Integration and Design of Low Speed PMSGs by Exploiting SRF-PLL-Based Sensorless Control and Holistic Modeling

This article proposes a holistic co-design framework with a low-cost approach for a permanent magnet synchronous generator (PMSG) that enables to optimizes both the electromagnetic and mechanical design, in conjunction with the injection of the maximum available power towards the power grid through a controlled electronic back-to-back converter. The proposed sensorless controller includes a hybrid PLL with a dynamically adjustable tabulated gains system and a feedforward frequency estimator. These add-ons allow to precisely track the speed and angle of the rotor shaft for near-zero speeds. This methodology includes the development of analytical models for the structural, magnetic and electrical components. The efficiency and performance of the machine and controller is verified by simulation under different load conditions and high angular speed variability of a 1.5 kW scale prototype in JMAG and Matlab & Simulink™ environments, reaching an efficiency of 80%.

Adaptive Position Observer for Multimode Wind-BES Based Microgrid Interfaced to Distribution Network

This article presents a robust adaptive position observer (RAPO) for implementing encoder-less speed control for permanent magnet synchronous generator (PMSG). The PMSG is driven by a wind turbine. The basic structure of sliding mode observer (SMO) includes a discontinuous signum function and low pass filter, which introduces not only chattering but also delay in the estimated position. To deal with the issue of classical SMO, RAPO consisting of sigmoid function based continuous super twisting SMO (CSTSMO) followed by a multilayered fourth order generalized integrator (MFGI) is used for this purpose. The CSTSMO is robust and with continuous switching function, it provides results with less chattering. The MFGI filters out the lower order dominating harmonics and ensues the fundamental signals, which helps in calculating accurate position and speed of PMSG. This technique is implemented on a wind battery energy storage based microgrid, which is operable in <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">off</small> -grid as well as in grid interfaced mode. This microgrid is suitable for rural areas, which suffers from the grid unavailability. Seamless transition between the operating modes is included for avoiding transients in the system during de-synchronization or resynchronization of utility grid. Furthermore, the system is proficient to mitigate some of the power quality issues. The system model is built in MATLAB/Simulink software and simulated results are validated through hardware results.

Permanent Magnet Synchronous Generator Connected to a Grid via a High Speed Sliding Mode Control

Wind power generation has recently received a lot of attention in terms of generating electricity, and it has emerged as one of the most important sources of alternative energy. Maximum power generation from a wind energy conversion system (WECS) necessitates accurate estimation of aerodynamic torque and system uncertainties. Regulating the wind energy conversion system (WECS) under varying wind speeds and improving the quality of electrical power delivered to the grid has become a difficult issue in recent years. A permanent magnet synchronous generator (PMSG) is used in the grid-connected wind-turbine system under investigation, followed by back-to-back bidirectional converters. The machine-side converter (MSC) controls the PMSG speed, while the grid-side converter (GSC) controls the DC bus voltage and maintains the unity power factor. The control approach is second-order sliding mode controls, which are used to regulate a nonlinear wind energy conversion system while reducing chattering, which causes mechanical wear when using first-order sliding mode controls. The sliding mode control is created using the modified super-twisting method. Both the power and control components are built and simulated in the same MATLAB/Simulink environment. The study successfully decreased the chattering effect caused by the switching gain owing to the high activity of the control input.

Studies Regarding the Modeling of a Wind Turbine with Energy Storage

This paper presents the modeling in Matlab-Simulink of a stand-alone wind turbine system with energy storage dedicated for small power wind turbines of 3kW with a variable speed permanent magnet synchronous generator (PMSG), diode rectifier bridge, buck-boost converter, bidirectional charge controller, transformer, inverter, ac loads and energy storage devices. Are presented the general system configuration, the Simulink block diagram and the main simulated characteristics resulting from the dynamic performances during the wind speed variation.

Maximum power tracking of variable‐speed wind energy conversion systems based on a near‐optimal servomechanism control system

AbstractIn this article, integral servomechanism based state‐dependent Riccati equation (SDRE) nonlinear output feedback control for wind energy conversion systems (WECSs) has been proposed. The numerical off‐line solving the proposed SDRE control requires to formulate algebraic Riccati equation and algebraic Lyapunov equation. This method approximates the solution of SDRE with Taylor series expansions which are solved with MATLAB solvers. The maximum power point tracking is achieved by defining relation between the optimal angular shaft speed and maximum power providing optimal tip speed ratio in variable‐speed WECSs. The proposed control can significantly reduce the angular shaft speed errors of the permanent magnet synchronous generator (PMSG)‐based WECSs without use of disturbance observers to compensate model uncertainties, modeling errors and noise as in the conventional SDRE control method. The simulation results demonstrate the superior results under mean average errors and root mean square error evaluation methods of the angular shaft speed of PMSG. The performance of the proposed integral servomechanism based SDRE control system has been improved by 80.67% and 80.05% in both scenarios compared to the conventional SDRE control based on compensation technique with disturbance observers.

Analysis and Performance Of Grid Connected Straight Driven Pmsg Based Wind Turbines

Permanent-magnet synchronous generator (PMSG) are used widely in wind turbine applications. The performance analysis of PMSG can be enhanced by adopting a number of control mechanisms with the benefit of advanced optimization techniques. Renewable energy is harnessed from continuously replenishing natural processes. Some commonly known are sunlight, water, wind, tides, geothermal heat and various forms of biomass. The focus on renewable energy has over the past few decades intensified greatly. This paper presents modeling and control strategy for the grid connected wind turbine system based on Permanent Magnet Synchronous Generator (PMSG). The considered system is based on back-to-back converter topology. The Grid Side Converter (GSC) achieves the DC bus voltage control and unity power factor. The Machine Side Converter (MSC) assures the PMSG speed control. The PMSG is used as a variable speed generator and connected directly to the turbine without gearbox. The pitch angle control is not either considered in this study. Further, Optimal Tip Speed Ratio based MPPT control strategy is used to ensure the most energy efficiency whatever the wind speed variations. A filter (L) is put between the GSC and the grid to reduce current ripple and to improve the injected power quality.During grid faults, a hierarchical coordinated control scheme for the generator-side converter, main grid-side converter and auxiliary grid-side converter, depending on the grid voltage sags, is presented to enhance the low voltage ride through (LVRT) capability of the direct-driven PMSG WT.&#x0D;

Voltage control for variable speed wind turbine using buck converter based on PID controller

Currently, energy diversification is needed to overcome the limitations of fossil energy as a fuel for electricity generation. In Indonesia, one source of renewable energy that has great potential is wind energy. Wind energy conversion system is an environmentally friendly electricity generator with unlimited availability. However, the electrical energy produced depends on the fluctuating wind speed so that it produces a fluctuating voltage. Variable speed wind turbine is one of the most widely used wind turbine types because it has better efficiency but requires control to overcome the fluctuations in the voltage generated. This paper presents voltage control on a prototype variable speed wind turbine with a permanent magnet synchronous generator (PMSG) and buck converter. The output voltage generated by the PMSG will be rectified by a three-phase uncontrolled rectifier. Voltage control is done through the duty cycle settings on the buck converter that is connected to the battery for energy storage. PID controller is used to set the duty cycle of PWM pulses with a switching frequency of 31.5 kHz. The Propotional Integrator Differensiator (PID) controller is embedded in the microcontroller. Based on the test results, the resulting output voltage can be held constant at 14V by providing variations in wind speed changes which are simulated through PMSG speed changes. Transient responses with the fastest settling time of 1.2 s were obtained with the PID controller parameter values Kp = 0.6, Ki = 0.15 and Kd = 0.6.

SSO risk evaluation for grid-connected PMSG-based wind farm based on sequential Monte Carlo simulation

In a grid-connected wind farm based on permanent magnet synchronous generators (PMSGs), the wind speed and the number of operating PMSGs are the two most important influencing factors with stochastic nature on subsynchronous oscillation (SSO) from the point view of the farm. This paper proposes a method of unstable SSO risk evaluation for grid-connected PMSG-based wind farm based on sequential Monte Carlo simulation (SMCS). The determination of critical wind speed (CWS) of SSO and the sequential simulation strategy of wind speed states and PMSG states in a wind farm at the same wind speed (S-WF) as well as in a wind farm at different wind speeds (D-WF), are studied. Five indices evaluating the expectation, duration, frequency and energy loss of SSO risk are proposed. Moreover, a strategy to reduce SSO risk by adjusting the cut-in wind speed is discussed. The effectivenesses of the discussed issues in the paper are proved by the case studies of a 750-PMSG wind farm based on the actual wind speed data collected.

A Controller for Optimum Electrical Power Extraction from a Small Grid-Interconnected Wind Turbine

Currently, wind power is the fastest-growing means of electricity generation in the world. To obtain the maximum efficiency from the wind energy conversion system, it is important that the control strategy design is carried out in the best possible way. In fact, besides regulating the frequency and output voltage of the electrical signal, these strategies should also extract energy from wind power at the maximum level of efficiency. With advances in micro-controllers and electronic components, the design and implementation of efficient controllers are steadily improving. This paper presents a maximum power point tracking controller scheme for a small wind energy conversion system with a variable speed permanent magnet synchronous generator. With the controller, the system extracts optimum possible power from the wind speed reaching the wind turbine and feeds it to the grid at constant voltage and frequency based on the AC–DC–AC conversion system. A MATLAB/SimPowerSystems environment was used to carry out the simulations of the system. Simulation results were analyzed under variable wind speed and load conditions, exhibiting the performance of the proposed controller. It was observed that the controllers can extract maximum power and regulate the voltage and frequency under such variable conditions. Extensive results are included in the paper.

Model-based design of variable speed non-salient pole permanent magnet synchronous generator for urban water pipeline energy harvester

This paper proposes the model-based design methodology of a 60-kW direct drive variable speed permanent magnet synchronous generator (PMSG) used in an urban water pipeline energy harvesting system. The whole study aims to design the PMSG considering different system parameters of the energy harvesting system such as the mechanical parameters, electric circuit, power electronics and the variable speed drive operation. The electric and geometric parameters of the PMSG is then designed based on different design constraints imposed by the system. To incorporate the effect of the variable speed drive into the PMSG electric parameters, this work introduces a parameter called κ, which can map the electric parameter variations with the variation of the PMSG input speed profile. This proposed work achieved a successful coupling among the system mechanical and variable speed drive parameters with the PMSG electric and geometric parameters. The coupling is performed in a python-based environment which couples MATLAB and Altair FLUX. The results are tested and validated against the desired values of the PMSG which shows a good agreement among different results. This whole design process can be useful in achieving a model-based design that can provide a detail analysis option before prototyping and testing different components of the harvester system.

Variable speed PMSG design and implementation for wind driven welding power source

PurposeThe purpose of this paper is the attempt to model a variable speed permanent magnet synchronous generator (PMSG) for extracting a standalone power source to assuage the needs of a welding application. The emphasis orients to evolve a framework for the effective exploration of renewable energy resource and prevent the injection of grid harmonics.Design/methodology/approachThe system involves the use of self-commutated dc-dc converter interfaces to extradite the current and voltage requirements of the welding attributes. The philosophy incites a pulse width formulation for reducing the voltage ripples in the dc output and improving the time response characteristics.FindingsThe proper selection of closed loop Fuzzy tuned PI control ensures the restriction on the magnitude of the current drawn from the source, enhances the dynamic response and betters steady state response.Originality/valuePMSG-based welding power source with parallel-connected cascaded buck fed cuk converters. MATLAB-based simulation of the methodology offer interesting results in the sense it orchestrates the range of converter operation and the ability to provide a high-quality weld without polluting the ac mains. The experimental prototype further proliferates to validate the simulated performance and claims a space for its use in the real-world utilities.

Speed controller of wind turbine emulator using variable speed drive based on PI method

The wind turbine system as a power plant is growing rapidly in line with the electrical energy needs and limitations of fossil energy as a source of electrical energy. Many research has been carried out to develop wind turbine systems and improve system efficiency. Research on wind turbine systems requires wind turbine emulators to simulate the behaviour of wind turbines against changes in wind speed. In this paper presents a design of speed controller based on PI controller for a Wind Turbine Emulator (WTE) using a Variable Speed Drive (VSD). WTE consists of VSD, microcontroller, 3 phase induction motor, Permanent Magnet Synchronous Generator (PMSG) and speed sensor. PMSG speed depends on wind speed. At certain wind speeds, PMSG will rotate at a certain value. WTE will adjust the speed of the induction motor according to a certain wind speed to drive PMSG. Motor and PMSG rotation speed are measured by rotary encoder sensor as speed sensor and feedback for WTE. Proportional-integral method is used to control the speed of a 3 phase induction motor through VSD analogue input. Based on experiment result, PI controller can adjust speed of induction motor so that PMSG will rotate according to a certain wind speed. WTE with PI controller controls the speed of induction motor at settling time 9s to simulate wind speed through PMSG speed controlling.

PWM-Based Optimal Model Predictive Control for Variable Speed Generating Units

This article investigates the dc-link voltage control of an active rectifier that is supplied by a variable speed permanent magnet synchronous generator. This configuration is commonly encountered in gearless wind energy conversion systems as well as in variable speed generating units. The proposed control strategy uses an optimal voltage vector based modulated model predictive control (MPC) to achieve direct power control. The studied scheme combines the advantages of finite control set MPC and control techniques that use pulsewidth modulator. The fast dynamics of the former are obtained during large transients, and the constant switching frequency operation, of the latter, is ensured in steady state. At each sampling instant, all the switching states are evaluated and the two adjacent states that give minimum error in the controlled variables are selected. The duty cycle of each of these vectors is computed through linear combination and appropriately limited for overmodulation. Simulations and cosimulation results presented in this article show interesting results. The control strategy has been developed on a field-programmable gate array control platform and experimental results at steady state are shown, with the aim to demonstrate the computational feasibility of the control strategy.

IoT Applications in Wind Energy Conversion Systems

Abstract Renewable energy reliability has been the main agenda nowadays, where the internet of things (IoT) is a crucial research direction with a lot of opportunities for improvement and challenging work. Data obtained from IoT is converted into actionable information to improve wind turbine performance, driving wind energy cost down and reducing risk. However, the implementation in IoT is a challenging task because the wind turbine system level and component level need real-time control. So, this paper is dedicated to investigating wind resource assessment and lifetime estimation of wind power modules using IoT. To illustrate this issue, a model is built with sub-models of an aerodynamic rotor connected directly to a multi-pole variable speed permanent magnet synchronous generator (PMSG) with variable speed control, pitch angle control and full-scale converter connected to the grid. Besides, a large number of various sensors for measurement of wind parameters are integrated with IoT. Simulations are constructed with Matlab/Simulink and IoT ’Thingspeak’ Mathworks web service. IoT has proved to increase the reliability of measurement strategies, monitoring accuracy, and quality assurance.

Control of a new stand-alone wind turbine-based variable speed permanent magnet synchronous generator using quasi-Z-source inverter

In this paper a new variable speed permanent magnet synchronous generator (PMSG)-based stand-alone wind energy conversion system (SWECS) is proposed. The interface between the PMSG and the isolated load is accomplished by a quasi-Z-source inverter (qZSI) with battery storage system. The battery-assisted qZSI can balance the stochastic fluctuations of the wind power injected to the load and improve the voltage and frequency control. In addition to the battery storage, a dump load is used in the proposed SWECS to better maintain the active power balance and stability of the dc-link voltage during over-generation condition as well as sudden load changes. The proposed control system is able to provide an uninterrupted and reliable supply to sensitive loads under various power generation scenarios of the SWECS and sudden changes in the load demand. Moreover, the proposed controller provides maximum power point tracking (MPPT) which is essential for optimum operation of the SWECS. The validity of the proposed system is proved by simulation results carried out using MATLAB/SIMULINK.

High-order sliding mode control for variable speed PMSG wind turbine based disturbance observer

This paper introduces a model-based control system for variable speed wind energy conversion system (VSWECS)-based permanent magnet synchronous generator (PMSG). Comparing to traditional wind turbines operating methods, these variable speed systems have the advantages of increasing the energy capture and reducing the mechanical stress. In order to exploit this latest advantage, a high order sliding mode (HOSM) control strategy has been developed to enhance system performances, ensure the maximum power point tracking (MPPT) and track the generator reference speed. Moreover, for the WT system, the turbine torque is considered as an immeasurable disturbance. Therefore, using a modified disturbance observer will allow direct tracking of the maximum power point. The stability analysis of the system has been proved using the Lyapunov theory. Finally, simulation results have been presented to verify the proposed approach efficiency.

Sliding Mode Control for PMSG-based Wind Power System

Variable structure control has proven particularly suitable to variable speed wind energy conversion system control, being easy to implement by the already existing electronics. Its main drawback is an increase of mechanical stress due to chattering, which can however be alleviated by various methods. This paper proposes a sliding mode approach for tracking the energetic optimum of a variable speed permanent magnet synchronous generator PMSG. The sliding surface is systematically derived from imposing a desired reduced-order dynamics and allows the turbine operation more or less close to the optimal regimes characteristic, according to an imposed trade-off between the torque (control input) ripple and the optimum tracking. In this way, by torque controlling the generator, a multipurpose (energy-reliability) optimization is actually achieved.