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 order to ensure three-phase grid-connected inverter output voltage symmetry under unbalanced grid voltage, an improved control strategy is proposed in this paper. The proposed control strategy includes power, voltage and current three loops. The complex coefficient-filter (CCF) is used to obtain the positive and negative sequence of unbalance output voltage and current during the grid faults. By...
Under the condition of low short circuit capacity and high grid impedance of weak grid, the grid voltage is easily fluctuated due to the load change, affecting the power quality of the grid. In view of this problem, firstly, this paper analyzes the principle of the grid-connected voltage change caused by the load change. Secondly, an improved voltage-power control method (PQ-U) for three-phase grid-connected...
The high line impedance and load fluctuations of weak grid can easily lead to grid voltage fluctuations and other issues. In order to make the grid-connected PV inverter have strong robustness and improve the dynamic response speed, the active power control method of PV inverter based on passive theory is proposed. Firstly, the control strategy of the power outer loop is given, and the Euler-Lagrange...
The dynamic characteristic of traditional controllers is not good enough especially when DC voltage sags or load changes abruptly. Plus, static error would be generated if the input is an AC signal. In this paper, PR controller is used to solve above problems. This article presents the transfer function of PR controller by theoretical analysis, At last, both simulation and experiment achieved the...
This paper uses CT to gain the energy directly from the high-voltage power line, which is to address the problem of power supply for monitoring system of dynamic increasing capacity in high voltage side of transmission line. The draw-out power coil can induce voltage from the transmission line whose current ranges from 50 to 1000A. Then after rectifying, filtering, voltage reduction and voltage stabilization,...
The proposed constant on-time control DC-DC converter removes the need of conventional equivalent series resistor (ESR) compensation and simultaneously aims to eliminate equivalent series inductor (ESL) effect of the output capacitor. Since the on-time period is set simply by input and output voltages, the switching frequency in continuous conduction mode (CCM) operation is relatively constant over...
This paper analyzes a new control algorithm about the input power feed-forward loop control based on the traditional double-loop control strategy. The input power of PV system is used as a reference component of inner current closed-loop, so the reference of the current contains the message of input power. Thus the proposed algorithm can improve the dynamic response of the PV system if mutations appear...
Active power filter has been proved to be a useful approach to eliminate current harmonics caused by nonlinear loads. This paper proposes a fuzzy controller with self-adjustable factor to control DC-link voltage of active power filter. The distinctive advantage of the fuzzy controller is that its fuzzy control rules can be modified according to the real system states automatically and instantaneously,...
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.