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.
DC/DC converters have been tremendously utilized nowadays. In some special applications such as military, aerospace, and precision instrumentation, the output voltage ripple of DC/DC converters has to be maintained in an acceptable level to achieve superior performance. For example, DC/DC converters are tied with inverter for adjustable speed motor controls or renewable energy interface with utility...
A networked control method for multi-inverter parallel system is proposed in this paper. Current-sharing control strategy and communication design are described. TOD (Try-Once-Discarded) scheduling mode is used to realize the real-time and accurate transmission, and the Joint scheduling algorithm of TOD is implemented to predict the networked control system performance with network time-delay. The...
A dual mode time-sharing inverter has higher efficiency than other type grid-connected inverter due to only one power stage of it working in high frequency state at any time. In this paper, small signal modeling of this inverter is carried out, which reveals that the control-to-grid current transfer function of this inverter has a right half plane zero at low frequency during the “Boost” operating...
This paper describes a fast torque control system of permanent magnet synchronous motor (PMSM) based on model predictive control (MPC) considering overmodulation region of inverter. In overmodulation region, output voltage of inverter contains harmonic voltage which influences performance of current control and can't be avoided. To consider influences of harmonic voltage, we use a harmonic voltage...
DC injection limits into the AC network are an important power quality control requirement for grid-connected photovoltaic systems. Most publications on DC offset controllers focus only on their steady state performance. It is important to consider their dynamic performance especially in terms of speed of response and stability. In this paper a mathematical model for a digitally implemented DC offset...
Multiple motors connected to a single closed-loop inverter drive is a common type of drive topology which has wide application in steel processing industry, electric railway systems and electric vehicles. But condition monitoring for this type of drive configuration remains largely unexplored. This paper proposes a new method to detect the stator turn-to-turn fault in a multiple-motor drive system...
The fast changes in the reactive power consumption can cause considerable variations at the load-side and can influence on the operation of other power consumers which and point of common coupling (PCC) voltage. In this paper, a current control strategy based on sigma delta modulation (SigmaDeltaM) is presented for the interfacing DG inverter. The inverter is called sigma-delta based current controlled...
Three-phase four-leg inverter has powerful ability to effectively treat unbalance and nonlinear loads, which outputs three phase symmetrical voltages. A novel control scheme with PD output voltage instantaneous-value feedback inner loop for voltage PID is proposed based on the model of three-phase four-leg inverter. The inner loop is designed to improve dynamic performance and the voltage external...
Islanding detection and anti-islanding protection are the essential functions of the gird-connected inverter in DG systems. This paper focuses on the non-detection zone (NDZ) with passive islanding detection method for the DG system with the current control scheme. The parameters of the point of common coupling such as the voltage amplitude and frequency are studied through mathematical derivation...
The aim of this paper is to propose an over current limitation and voltage control strategy for a grid connected inverter with a LC output filter used in distributed generation and in case of voltage sag. This strategy relies on the control of LC output filter voltage with a resonant controller. This controller has to control current and load voltage throughout voltage sag. Generally, resonant controller...
The paper proposes frequency shift acceleration control (FSAC) for anti-islanding of an inverter-based distributed generator. The key concept is to disturb an islanded system frequency by controlling reactive current output in d-q frame, and accelerate the resulting frequency shift using an acceleration gain. Design method of the acceleration gain is proposed using analytical approaches, based on...
This paper presents a modified adaptive Kalman filter for sensorless current control of a three-phase inverter based distributed generation system. The delay introduced by measurements and the digital signal processor is compensated using a modified Kalman filter. The states of control variables can be estimated one sample in advance and the number of the measurement sensors can be reduced. For system...
This paper proposes a stationary frame-based sensorless predictive current controller with zero steady state error for inverter based distribution generation systems. Analytical expressions for the error sources in the predictive current controller are derived. The stability margin for the predictive current control gain is also presented. A digital adaptive algorithm based on the steepest descent...
LCL filter offers a better choice of attenuating switching frequency harmonics, since compared with L or LC filters the value of required inductance is smaller. But LCL filter may cause resonance which is a disaster for the systempsilas stability. In order to solve the problem, a two-current-loop control strategy which includes grid-current outer loop and filter-capacitor-current inner loop is used...
A new current control method for the utility interactive inverter based on deadbeat control with FPGA based hardware controller is proposed. In the utility interactive system, the utility line voltage should be included in the system model, so the procedure to derive the discrete time system model is the key point to achieve the accurate control characteristics. In the proposed method, different approaches...
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.