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.
Tokamak coil power supply for superconductivity coil of ITER(International Thermonuclear Experimental Reactor) requires fast dynamic performance of di/dt and smooth changeover of current direction. To meet the specification high performance this power supply is designed for 12-pulse thyristor dual converter with interphase reactor(IPR). The study about improving current control transient response...
This paper describes the design of a digital control for PWM current source rectifiers (CSRs) in the range of 1 - 10MVA. A cascaded control structure is proposed: the inner loop controls the grid currents and the outer loop controls the dc-link current. The proposed grid-current control combines state feedback for active damping of the LC-filter with a servo compensator to increase robustness and...
New constant-voltage constant-current ac power supply is presented. Our original Variable Capacitance Device is utilized in the power stage as linear reactance device. This circuit theoretically makes no distortion of output voltage waveform and a high efficiency can be obtained. For output voltage/current control and input power-factor correction, two Variable Capacitance Devices were employed as...
Smart grids offer a wide application domain for power electronics. In fact, every distributed energy resource (DER) includes an electronic power processor (Switching Power Interface, SPI) which controls the currents drawn from the grid and can be driven to optimize the power flow, improve voltage stability and increase distribution efficiency. For these aims, such distributed SPIs must perform cooperatively...
This paper presents a hysteresis based current control PWM named "Hi-PWM”, which has several advantages such as quick response of current, less fluctuation of switching frequency and less harmonic components. In this paper, the analysis of Hi-PWM applied railway traction system is explained. This paper also shows temperature and loss simulation of power device using Hi-PWM and experiment result...
This paper presents a novel selective control algorithm for a shunt active filter. Based on the proposed control algorithm, the active filter drains controlled currents in order to improve the performance of the passive filters and also to minimize a specific harmonic component of the system voltages. The controlled currents produced by the active filter are determined through the system voltages,...
PM motor drive systems are widely used for industrial drives. However, PM motors basically produce the torque ripple due to the fluctuation of the magnetic field distribution. Dead time of the inverter, offset of sensors and current measurement errors lead to the torque ripple, too. The torque ripple leads vibration noises. In this paper, we proposed a torque ripple suppression method based on perfect...
This paper propose a new current control system for IPMSM to reduce harmonic currents caused by the overmoduration and a non-sinusoidal magnetic flux distribution on the rotor. The harmonic currents have problems with making a current control system of IPMSMs unstable easily. The proposed current control system has two current controllers. One of them controls fundamental current to satisfy the required...
A new magnetic-flux saturation model has been developed for permanent magnet synchronous motors. In the new model, simple first-order functions Φd(id, iq) and Φq(id, iq) express the relationships between d-q axis currents and each axis magnetic flux, considering magnetic saturation and cross-coupling effects. Taking advantage of these new features, we developed a current controller that introduced...
The proposed paper studies the transient operation of a grid connected power converter designed for microgrid applications. A control system consisting of an improved droop characteristic control using synchronous frame PI regulators including a feed-forward disturbance decoupling controller is developed and tested. The proposed control system can operate in two main operating modes: islanded and...
A robust self-interleaving mechanism for parallel hysteresis current controlled inverters is proposed, with sustained switching under all load conditions. A fast interleaving technique that can be applied for normal load conditions is combined with a self-interleaving mechanism, which ensures correct switching during voltage clamping operation. A minimum switching frequency and maximum duty cycle...
Regular control of parallel active power filter (PAPF) based on the p-q theory is studied in this paper. After evolutional reduction of the control diagram and mathematic derivation of the p-q theory, a generalized conclusion is drawn: regular control scheme could be regarded as a composite control with feedback of dc-link voltage and feedforward of the fundamental load current; under different compensation...
In this paper, modeling and control of spiral motor is proposed. The voltage equation and motion equation of the spiral motor is proposed. Based on this modeling, control system for the spiral motor is proposed. The proposed controller consists of three parts; the first part is PI current controller with back EMF compensation specialized for spiral motor, the second part is disturbance observer based...
Integration of renewable energy sources (RES) with significant capacity, including photovoltaic (PV) generation systems, into the grid is expected within ten years. Such RESs bring to the grid not only their benefits but also some technical problems, as increase of harmonic currents. Compliance with the technical requirements for harmonic current is necessary for successful increase of RES capacity...
Harmonic resonances of the distribution power system have become a significant issue in recent years, due to extensive use of either nonlinear loadings or inverter-based distributed generation systems. This paper presents resonant current regulation to enhance the damping capability of the discrete frequency tuning active filter for suppressing power system harmonics. The resonant current regulator,...
This paper presents a hysteresis based current control PWM named “Hi-PWM”, which has several advantages such as quick response of current, less fluctuation of switching frequency and less harmonic components. In this paper, the improvement of Hi-PWM is explained, which realizes switching frequency control and output voltage calculation. This paper also shows simulation results driving induction motor...
Speed and current closed loops control represent the heart of any advanced AC servo drive. These inner loops usually feature high-dynamic feedback control, with possible axes decoupling and a straight feedforward action of the back-electromotive force (back-EMF). More sophisticated techniques as single-rate or multi-rate control could be exploited for both speed and current closed loops, and their...
Generally, one should use one large input capacitor rated from thousands of micro farads to ten-thousands of micro farads when applying reflex method for battery charger. However, large capacitor is very expensive. This paper proposes a novel control strategy with separate charging time to reduce the loading of the input capacitor, so that one may use a smaller input capacitor, and then reduce the...
Feedback sensor isolation is often an expensive necessity in power converters, for reasons of safety and electromagnetic compatibility. A disturbance observer-based control strategy for a dual-output resonant converter is proposed to overcome this problem. Current control of two LED loads is achieved through estimation rather than measurement. Robustness against temperature changes, which have significant...
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...
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.