Reactive power control and performance analysis of doubly fed induction generatorin micro grid

Indonesian Journal of Electrical Engineering and Computer Science Vol. 28, No. 3, December 2022, pp. 1214~1226 ISSN: 2502-4752, DOI: 10.11591/ijeecs.v28.i3.pp1214-1226  1214 Reactive power control and performance analysis of doubly fed induction generatorin micro grid Syed Sarfaraz Nawaz1, Sandipam Tara Kalyani2 1 Department of Electrical and Electronics Engineering, Gokaraju Rangaraju Institute of Engineering and Technology, Hyderabad, India 2 Department of Electrical and Electronics Engineering, Jawaharlal Nehru Technological University, Hyderabad, India Article Info ABSTRACT Article history: For both financial and environmental considerations, the power system includes a large number of solar and wind generating plants. In reality, wind energy has always been used using a doubly fed induction generator (DFIG) based variable speed wind turbine. This study examines the effectiveness of indirect control of a doubly fed induction generator for closed loop reactive power adjustment. A wind energy conversion system with continuous grid power's design, analysis, and MATLAB simulation are also covered. For DFIG to work reliably and be controlled to ensure stability for the power system, a seamless transition mode change is required. The horizontal axis wind turbine technology provides the necessary reactive power into the grid under all unexpected circumstances. The concept of DFIG mathematical modelling is covered. Various simulated outputs at loading circumstances are shown, along with separate control of active and reactive powers and variations in prime mover speed and excitation. This study examines the performance enhancement of DFIG using its grid-based proportional integral (PI), proportional integral derivative (PID), and fractional order proportional integral derivative (FOPID) controllers. Based on the thorough simulation findings, the type of control system that gives the efficient performance of DFIG in grid is ultimately decided. These simulation results demonstrate how the suggested controllers outperform the current controllers in terms of improving system performance. Received Feb 18, 2022 Revised Aug 16, 2022 Accepted Sep 6, 2022 Keywords: Doubly fed induction generator Fractional order PID Proportional integral Proportional integral derivative Reactive power This is an open access article under the CC BY-SA license. Corresponding Author: Syed Sarfaraz Nawaz Department of Electrical and Electronics Engineering GokarajuRangaraju Institute of Engineering and Technology Hyderabad, India Email: 1. INTRODUCTION The concept of free waste production, saving andstrong electric power arises as a result ofthe only source of natural energy, fossil fuelsshrinkage, global warming and gas emissions. Renewableenergy sources play an important role in solving most past problems. Doubly fed induction generator (DFIG) can increase productivity, lower costs and losses, modify the power feature, offer variable speed, and regulate both real and reactive power [1]-[4]. The doubly fed induction generator is one of the most popular generators utilised in high power wind generation (DFIG). The rotor of the DFIG is connected to the grid via a back-to-back power electronic converter [5]-[10], whilst the stator is connected directly to the micro grid. The grid is directly connected to the DFIG stator windings, while the grid is connected to the rotor windings via back-to-back converters, rotor side converters, and grid side converters (GSC) [11]–[16]. These controller controlspower and dc link voltage respectively. The capacity to operate across a wide range of Journal homepage: http://ijeecs.iaescore.com Indonesian J Elec Eng & Comp Sci ISSN: 2502-4752  1215 wind speeds and the reduction in size and cost of power converters are two advantages of this type of machine [17]-[19]. Recent studies have focused on the use of sophisticated and robust controllers like regulation, pole placement and tracking (RST), Sliding mode controller, backstepping, and active disturbance rejection control active disturbance rejection control (ADRC) to enhance DFIG control and extract the most dependable and steady power from it. However, this kind of controllers has several drawbacks when dealing with grid defaults [20]-[24]. The control method used which is intended to control the outputpower provided grid. Such common controlsas a proportional-integral (PI) controller and proportional integral derivative (PID) is used because of its simplicity solid structure and performance. However, the maindisadvantages of these conventional controllers (PI and PID) arethat their performance is deteriorating due to changesoperating system conditions causeddemand increase [25], [26]. The major goals of this study are to develop a comprehensive MATLAB/Simulink mathematical model. Additionally, it provides a thorough comparison of the simulation results for PI, PID, and FOPID controllers. The auto tuner in MATLAB/Simulink is used to obtain the parameters of PI and PID controllers. Using grey wolf optimisation (GWO), the FOPID controller's parameters are obtained (GWO). These outcomes demonstrate how effective the suggested controllers perform. The DFIG block diagram is shown in Section 2. Then, in Section 3, the DFIG converter control operation is described. Section 4 presents the Simulink model of the DFIG with the added load. Section 5 discusses the Simulink MATLAB model of the DFIG based on PI, PID, or FOPID controller. Section 6 presents a mathematical model of the DFIG, while section 7 discusses the design of the controllers. Section 8 offers the simulation findings. The paper concludes with its conclusions in the end. 2. BLOCK DIAGRAM OF DFIG Figure 1 depicts the DFIG system's fundamental block diagram. The stator and rotor are coupled by the power electronic control system. The stator side converter's primary function is to maintain a steady DC link voltage. The back-to-back converter's reactive power consumption can be easily managed to keep the power factor at unity. Although the converter's capacity for power distribution reduces inaccuracy to a ratio of 1/4 of the output power of turbines, it nevertheless functions as a further device for compensation. Figure 1. Block diagram representation of DFIG The asynchronous machine's stator is directly connected to the grid, or the supply. The rotor of the asynchronous machine and the DC machine are combined in this lab model. When the direct current (DC) machine is running at a different speed, the rotor side converter acts as an inverter or adaptor. The identical procedure will be used by the grid side converter. Utilizing a prime mover (DC machine) running at varied speeds, the armature voltage control approach is utilised to achieve different DFIG speeds. The capacitor bank is connected to the stator terminals of the input device to provide the magnetic field required for the machine to function. Reactive power control and performance an (...truncated)