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.
The research on the application of the 3-phase high power PWM (Pulse Width Modulation) rectifier in the battery charge and discharge device has been a hotspot in the field of power electronics and control. As the traditional PID controller is difficult to achieve the optimum parameters, this paper proposes a new control method of PWM rectifier based on Genetic Algorithm (GA). The design of the PWM...
The design of the voltage loop and current loop of three-phase high power factor PWM rectifier was introduced, the strategy of dual-mode control that combine fuzzy control to PI regulator is proposed, which use fuzzy controller to obtain quick dynamic response when deviation is in small range and adopt PI regulator to realize no static error when deviation is in long range, improving the control accuracy...
A new asymmetrical hybrid multilevel inverter topology is presented. The new topology improve the number of the output voltage level greatly through cascading two five-level H-bridge cells. A hybrid PWM strategy is proposed for the new topology that the switches of different cells works in different switching frequency to low switching losses. Lastly, an experimental 17-level asymmetrical inverter...
This assay supposed one kind of asymmetrical multi-level inverter that based on the topology of cells cascading, every cell in this inverter is composed of one two-levels inverter series with several three-levels H bridges, the controlling system is constructed by DSP and FPGA. This article described the topology of this inverter and its controlling methods in detail. In final, tested this inverter's...
Modelling and simulation of closed loop controlled class D current source resonant inverter (CSRI) for ferromagnetic load is presented in this paper. The converter can operate effectively even for fluctuating source and it operates in zero-current switching mode. The switching devices are connected through a common ground and need only a single DC power supply for the gate driver circuitry. The aim...
A simple but powerful design method based on real-coded Genetic algorithms (GAs) to solve the minimization of the Total Harmonic Distortion (THD) criterion is obtained. GAs provides a much simpler approach to off-line tuning of Pulse width Modulation (PWM) switching angles than the rather complicated non-genetic optimization algorithms. Genetic algorithms are exploratory search and optimization procedures...
There is a strong trend in the photovoltaic (PV) inverter technology to use transformerless topologies in order to acquire higher efficiencies. This paper presents a single-phase five-level grid connected PV inverter with a novel dual reference modulation technique. Two reference signals identical to each other with an offset equivalent to the amplitude of the rectified inverted sine carrier signal...
Here introduces a monitor system technically based on ARM7 embedded micro processor (HMS30C7202) and Micro C/OS-II embedded operating system. The paper provides the scheme of the principal, introduces the connection method of outside signals, tells about how to transplant the Micro C/OS-II to the operating system, and shows the programming emphases and some source code of the majority of the program.
In order to meet the requirement of magnetic suspension bearings for high speed machine, the three-level PWM switching power amplifiers are designed and tested. The carrier triangular wave phase shift method is used in the design. The comparative study on the three-level PWM switching power amplifier with the two-level PWM switching power amplifier indicates that the three-level PWM technique can...
Firstly, to minimize the ripples of the electric magnetic torque and flux linkage produced in the conventional direct torque control (DTC) system for permanent magnet synchronous motors (PMSM); this paper proposes a expected space vector modulation (ESVM) strategy of DTC. The expected voltage was produced by SVM. PI controller was used in flux and torque controller, instead of hysteresis comparator...
The high efficiency power management IC (PMIC) with switching device is presented in this paper. PMIC is controlled with PWM control method in order to have high power efficiency at high current level. Dynamic threshold voltage CMOS (DT-CMOS) with low on-resistance is designed to decrease conduction loss. The threshold voltage of DT-CMOS drops as the gate voltage increases, resulting in a much higher...
LED has been applied in many aspects in daily life because of its advantages, and this trend will go on. Therefore, the research and design of the LED lighting driver becomes popular. In this article, system level design of a LED lighting driver based on switching power is described. The chip is designed with hysteretic control mode, and the peripheral circuit topology structure is buck converter...
The multilevel inverter utilization have been increased since the last decade. These new type of inverters are suitable in various high voltage & high power application due to their ability to synthesize waveforms with better harmonic spectrum and faithful output. This paper presents, two proposed scheme adopting the multicarrier pulse width modulation concept. The multicarrier pulse width modulation...
This paper presents analysis of time-ratio-controlled autotransformer as a mitigating device for voltage sag disturbance. Control circuit based on load RMS and voltage sag sensing circuit based on peak detection are employed. Commonly dynamic voltage restorer and STATCOM are employed for mitigation of voltage sag. The proposed system has less number of switching devices in comparison to commonly used...
This paper presents a novel model for average current control that can be applied to the buck-cascaded buck-boost converter (BuCBB) with two independently controlled switches in universal input power factor correction (PFC) circuits. The proposed BuCBB PFC model consists an averaged BuCBB topology with all the switching elements replaced by dependent sources and an average current control scheme with...
The magnetic circuit of switched reluctance motor (SRM) is seriously nonlinear because certain parts of the stator and rotor may go into magnetic saturation and the mutual inductance will be large when the motor works at two-phase excitation. These factors make the control of winds current very difficult. This paper analyzed the inductance of 8/6 SRMs including mutual inductance. Then a novel current...
This paper mainly discusses several key technologies in high performance BLDCM. A brief summarization on present studies in the field of aviation and aerospace for the enhancement of reliability, efficiency and variable speed capability is given, and its research direction in the future also is looked ahead.
In a three-phase PWM voltage-source inverter, there have voltage losses that cannot be neglected between the reference voltage and the actual output voltage due to the dead time effect. The distortion of voltage leads to serious problems such as current waveform distortion and torque oscillation of motor driving systems. In this paper, an improved method which effective reduces the losses of voltage...
This paper analyzes the maximal power loss in the output diode of flyback switching converter operating in both continuous conducting mode (CCM) and discontinuous conducting mode (DCM). Comparing with the previous work, this paper extends the condition, under which the maximal power loss of the output diode occurs, from the CCM to the DCM. Three correlative tasks are included. Firstly, through an...
This paper deals with topologies of circuits and strategies of modulation for multilevel inverters. There is a close relationship between these two factors. A new Hybrid multilevel inverter based on the features of the NPC inverter and the Cascade inverter is recommended. Its three modulation strategies and voltages spectrum characteristics are analyzed. The spectrum expressions of the continuous...
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.