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.
With the ever-increasing requirements in industrial manufacturing as well as in the daily life activities of modern society, the control systems equipped with two or more parallel PWM rectifiers rather than solely with a PWM rectifier are widely used to meet the system demands of higher productivity, reliability and safety. Although the control result of the system using conventional PI controller...
This work presents the extended capabilities of a single-phase Pulse Width Modulation (PWM) rectifier to achieve a unity power factor (PF) in the Point of Common Coupling (PCC). It can act as a dynamic var compensator, fixed var compensator and Active Power Filter (APF). To accomplish such tasks a control scheme based in two cascaded loops is used. The outer loop regulates the dc bus voltage and provides...
Pulse width modulated rectifier is a very popular topic nowadays. The modern industrial production demands continuous and lossless conversion of electrical energy parameters. This need leads to wide spread of power semiconductor converters. The rapid development in power electronics enables to apply sophisticated control methods that eliminate negative side effects of the power converters on the supply...
Two techniques are presented to balance the filter capacitor voltages of a multipulse rectifier with the active injection operating on a variable-frequency supply. The active injector consists of a low-rated bidirectional switch that modifies the behavior of a 12-pulse rectifier at either low or high frequency, resulting in 24-pulse or multilevel pulse width modulation operation, respectively. The...
Traditional control method of PWM(Pulse Width Modulation) rectifier has good dynamic and steady-state performance, But when PWM Rectifier worked under unbalanced voltages, various harmony powers occurred. Quality of output voltage and input current had been affected. Analyze unbalanced voltage and current through the method of symmetrical component, and two vector-oriented control strategy based on...
Nowadays, most of the electrical railway tractions, especially the high-speed tractions are using AC-DC-AC power driving system. The best choice for the AC-DC link is four-quadrant PWM rectifier, which can provide controllable DC link voltage and better power factor for the grid. In high power drive applications, the switch frequency of the power semiconductor device cannot be very high, usually less...
In this paper is presented the structure and working principle of the cascaded H-bridge multilevel converter with PWM rectifier and phase-shift transformer. Using the leak inductance as the filter reactor of the PWM rectifier can reducing the volume and cost of the converter; the phase-shift secondary side of the transformer can eliminate the current harmonics caused by the single power unit, restraining...
This paper presents an adaptive PWM control scheme of four-cell interleaved boost-type switching-mode rectifier, used as an input stage of auxiliary power supply of electrical vehicles, and its operation under regular, as well as under specific operating conditions - failure of one or more IGBTs.
Three-phase high-power rectifier has widely applied to electromotor and high-power AC-DC transformation, but there are many problems such as many harmonic waves and low power factor about high-power rectifier. Along with much request of green electrical source, it is more and more important to reduce its disturbance to electrical network. High-frequency PWM rectifier can adjust output voltage and...
This paper proposed a main circuit topology of cascaded compound current quality compensated device. Compared to the conventional topology, it used double PWM converter technology. PWM rectifier provided a stable DC voltage for the device, implemented input power factor approximately 1 and also achieved decoupling control of DC voltage and output current. PWM inverter used harmonic and reactive compound...
A control strategy of positive and negative sequence controllers for three phase voltage source PWM rectifier based on power-equation principle is proposed aim at eliminating the harmonic of dc output voltage. The strategy calculates the commands of positive and negative sequence currents using the equation principle of instantaneous power, and designs positive and negative sequence controllers to...
The main advantages of the high speed machine are small size and high power density. However, the high speed machine suffers from higher loss density and cooling difficulty due to small cooling area, especially the high frequency harmonic currents produced by the power conversion system increase the loss and temperature of high speed machine. The output high frequency AC power of the high speed PM...
In order to improve the performance of complementary half controlled three phase PWM boost rectifier, an improved control scheme including the current coordinate control and grid voltage oriented control is proposed. The current coordinate control is applied to obtain sinusoidal grid-side input currents and steady DC bus voltages. Grid voltage oriented control is applied to eliminate the impact of...
The objective of this paper is to model and simulate a three-phase Voltage Source Pulse Width Modulation (PWM) Rectifier Based on Direct Current Control feeding an indirect vector controlled Induction Motor Drive (VCIM) and 3-Level SVM based PMSM Drive. Based on the mathematical model of PWM rectifier, the dual close loop engineering design with decoupled feed-forward control is applied in the three...
A novel main circuit topology of voltage quality compensator (VQC) is proposed in this paper, composed of PWM rectifier and cascade H-bridges inverter. The three phase inverter is decoupling controlled. PWM rectifier is adopted to maintain the dc-bus voltage stably and provide or absorb real power. The inverter is controlled by carrier phase shifting with FPGA. The simulation model is set up on the...
The goal of the control strategy for three-phase pulse width modulation (PWM) rectifiers operating under unbalanced voltage conditions is to avoid ripple in the DC-link voltage and harmonics in the input AC currents. A stationary frame control scheme which regulates the instantaneous active power at the converter poles for minimizing of input/output harmonics is used. The design of the control loops...
This paper presents a PWM three-phase rectifier controlled to demand a sinusoidal source current in phase with the positive-sequence fundamental source voltage, providing unity displacement power factor. The operation of the rectifier is controlled so that in case of a nonlinear load connected to the grid, the power converter also operates as an active power filter, improving the global power quality...
This paper proposes a modified one-cycle-control (OCC) scheme for regulation of three-phase pulsewidth-modulated (PWM) rectifiers under unbalanced and distorted supply conditions. Mathematical analysis is presented to show the dominant harmonic voltage across the dc-link of PWM rectifier when controlled by the existing OCC scheme. Such ripple voltage may aggravate the harmonic distortion in input...
The application of conventional traction supply system for urban railway transportation implies huge energy waste and electrical pollution, in which the energy regenerated from the braking of vehicles cannot be feedback into AC grid. What's more, its DC output voltage fluctuates seriously with external loads, and AC harmonics on the grid side forms electrical pollution to the outside. This paper proposes...
The authors have devised a novel PWM control scheme capable of controlling a designated order harmonic while other low harmonic components are eliminated, based on the conventional low harmonic component elimination PWM control scheme. And it experimentally proved that the harmonic voltage in power systems could be suppressed, by means of controlling a self-commutated rectifier as a shunt active filter...
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.