The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In this paper, the relationship between real and reactive power sharing in islanded microgrid considering the complex impedance effect is analyzed. It is determined that traditional droop control has drawbacks in achieving accurate power sharing caused by the mismatched feeder line effect. In order to enhance the power sharing accuracy, an adaptive droop control using virtual impedance for islanded...
The photovoltaic (PV) source simulators are widely used to test solar inverters, evaluate their control algorithms and study their grid integration issues in the laboratory settings. Many commercial programmable dc power supplies can be re-programed to be PV simulators. Due to the bulky output dc capacitors, the dynamic response and the bandwidth of these PV simulators are significantly limited, which,...
This work explores reactive power compensation on a small photovoltaic generation at residential installation to enhance reliability on a Smart Grid. In order to accomplish this goal, the modulator values of the inverter are determined to obtain the allowable range of reactive power compensation in a photovoltaic system connected to the grid trough out a single-phase voltage source inverter. Mathematical...
The active power filter (APF) has already established itself as a prominent means of addressing harmonic pollution and other power quality issues. Current control of an APF is a key in achieving a good compensation performance. Generally, PI control is used owing to its simplicity and ease of implementation. However, using a proportional resonant (PR) controller can give an added advantage in tracking...
An improved deadbeat plus plug-in repetitive control scheme is proposed for grid-connected three-phase four-leg inverters to achieve fast and accurate feed-in grid current tracking. Discrete-time mathematical model of the three-phase four-leg grid-connected inverter is developed. An improved deadbeat (DB) plus plug-in repetitive control (RC) scheme is proposed to reject periodic disturbances while...
This paper presents the application of a multiple switching pattern selective harmonic elimination on three level inverter. The aim of this work is to eliminate low rank harmonics (3rd, 5th, 7th and 9th) from an AC voltage waveform generated by DC to AC converter and also control the fundamental component, the modulation algorithm is based on the Newton-Raphson method which is one of the simplest...
Microgrids with a high share of renewables may become the keystone of the new energy transition. With the present inverters interfacing the various DERs (Distributed Energy Resources) to microgrids, the stability of such power systems is threatened if the share of renewables increases. In this paper a robust solution to solve this problem is presented. The proposed solution is based on the concept...
The contribution deals with steady state estimation of an electromagnetic torque ripples and a current waveform of a two-phase induction motor (IM) supplied by an three-leg IGBT bridge connected voltage source inverter (VSI). The inverter's output voltage is controlled by a modified sinusoidal SPWM of the input DC voltage. The complex Fourier series analysis of the inverter's output voltage was made,...
Synchronverters are inverters that mimic the behavior of synchronous generators. In this paper, we propose modifications to the synchronverter algorithm to improve its stability and performance. The proposed modifications are implemented in software and do not require any changes in the inverter hardware. The first two modifications concern the control of the virtual field current in the synchronverter...
This paper presents the small signal model of a multi Photovoltaic (PV) inverter system to study the effect of controller and system parameters on the frequency modes of a microgrid. The paper describes the state space model of a system having two PV inverters connected by a line and working under droop control mode for active power sharing. The PV sources are working under load following mode and...
Due to the high-scale penetration of single-phase photovoltaic (PV) systems in distributed generation, a single-stage single-phase grid-connected PV system, with a nonlinear control strategy is presented in this paper. Using the general structure for synchronous dq0 frame, the controller is developed to obtain maximum power from the PV array regardless of the atmospheric conditions without the requirement...
In this work is present the comparison of two methods of controllers design and the model of a single phase inverter for island mode operation in a microgrid. These methods are: direct current conventional method based on frequency analysis that allows the design of a proportional-integral controller and a second method based on dc-ac coordinate transformation, that allows the design of a proportional...
A novel frequency-domain EMC modeling technique is proposed to predict the conducted electromagnetic interference (EMI) in a three-phase inverter system. The proposed model can predict the conducted emissions up to 30MHz. Moreover, the proposed model can analysis noise source and the noise propagation respectively. Based on the model, the influence of the IGBT stray capacitance on total EMI noise...
In this paper, a new continuouse current quasi Z-source inverter (CCQZSI) based on capacitor basic unit is proposed. By using n numbers of the basic units, the developed CCQZSI is proposed. High value of the boost factor is the main advantages of the proposed CCQZSI in comparison with the conventional Z-source inverter. This feature is obtained by considering same value of shoot-through (ST) duty...
This paper proposes a comprehensive analysis of switched boost inverter's (SBI) voltage and current equations, using specific switching method in continuous current mode (CCM) operation. The presented switching method makes SBI proper to be used in galvanic and electrochemical applications. The boundary amount of inductor between the two CCM and discontinuous current mode (DCM) operations is calculated...
In this work, three-phase single stage grid-connected photovoltaic system using current control inverter is simulated using Matlab/Simulink. To deal with varying irradiance conditions, the incremental conductance MPPT has been used, however in order to improve the power quality a three-level (NPC) inverter based SVM control together with LCL filter has been used. The main result of the project is...
This paper presents a new and simple voltage control strategy for three phase current source inverter (CSI) using finite-set model predictive control. The proposed method can ensure an interruptible power supply (UPS) for the local loads of an islanded grid connected CSI independently of the type of these loads. The control of the inverter's output voltages is performed using the discrete model prediction...
For LCL type grid-tied three-phase inverters, a model predictive controller is proposed. Through the controller, system performance indexes, i.e., current tracking, inductor loss, switching loss can be combined and then optimized. Since the controller is a constrained nonlinear problem, an on-line algorithm is presented which is based on branching and bounding method. Finally, through Matlab simulation...
A cyber-physical system (CPS) approach for branch and bound algorithm (BnB) based model predictive control (MPC) of permanent magnet synchronous machine (PMSM) drive system fed by three-level NPC inverter is proposed in this work. The proposed control strategy deals with both the physical states and a cyber state, i.e. the sampling frequency. With the help of cyber controller, the cyber resource and...
Based on double PWM structure, this paper analyzes the energy relationship between each part of the system according to the system energy flow in balanced energy state and unbalanced energy state and builds the energy mathematic model of double PWM. In order to solve the problems of DC bus voltage fluctuation and the mismatch in system output power and the motor power caused by the imbalance between...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.