PWM Power Supply Using SiC RESURF JFETs with High Speed Switching

400V/2.5A 4H-SiC JFETs, having a reduced surface field (RESURF) structure have been fabricated. Measurements on the on-resistance, blocking, and switching characteristics were carried out. It was confirmed that the JFET has fast switching characteristics. A demonstration of a Pulse Width Modulation (PWM) decoder using JFETs was carried out. The input waveform, which is pulse width modulated 20.5MHz at 4.1MHz sine wave, as able to be decoded at 4.1MHz sine wave.

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Design and Construction of an Inverter for University ICT Loads

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.e6338.038620 ◽

2020 ◽

Vol 8 (6) ◽

pp. 374-378

Keyword(s):

Pulse Width ◽

Pulse Width Modulation ◽

Sine Wave ◽

Simulation Software ◽

Switching Scheme ◽

Pulse Width Modulated ◽

Driver Circuit ◽

Single Phase Inverter ◽

The University ◽

Design And Construction

In trying to restore a stable power generation in this part of the world for effective research studies and to improve administrative duties in the University of Nigeria Nsukka, this paper discusses the design and construction of a single phase inverter for information communication and technology equipment’s (ICT) which includes printers, computers, and network switches etc. The inverter system converts the DC voltage from a battery to AC voltage. The output is a pure sine wave, with the voltage and frequency of the standard grid (50Hz, 230V). A pulse width modulated (PWM) switching scheme together with a full bridge converter and filter is use to realize this design. The sinusoidal pulse width modulation (SPWM) switching scheme is the main logic control circuit of this inverter and provides a PWM output using operational amplifiers and microcontroller. This logic circuit is connected to a driver circuit to ensure sufficient gate driving current and voltage for the full bridge converter (H-bridge) switches (power MOSFET). The pulse signals are used to drive MOSFET in a H-bridge configuration to produce an output that is bipolar The output of this inverter switches from positive to negative (bipolar). This output from the MOSFET when filtered produces a sine wave output. This project is implemented and simulated using MATLAB simulation software.

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Simulation of Three Phase Sine Wave Generation for Pulse Width Modulation (PWM)

International Journal of Scientific and Research Publications (IJSRP) ◽

10.29322/ijsrp.9.04.2019.p8807 ◽

2019 ◽

Vol 9 (4) ◽

pp. p8807

Author(s):

Toe Toe Hlaing

Keyword(s):

Pulse Width ◽

Pulse Width Modulation ◽

Sine Wave ◽

Wave Generation ◽

Three Phase

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Dynamic vacuum pressure tracking control with high-speed on-off valves

Proceedings of the Institution of Mechanical Engineers Part I Journal of Systems and Control Engineering ◽

10.1177/0959651818780866 ◽

2018 ◽

Vol 232 (10) ◽

pp. 1325-1336 ◽

Cited By ~ 1

Author(s):

Gang Yang ◽

Kai Chen ◽

Linglong Du ◽

Jingmin Du ◽

Baoren Li

Keyword(s):

Mass Flow ◽

Pulse Width ◽

High Speed ◽

Pulse Width Modulation ◽

Sliding Mode ◽

Tracking System ◽

Vacuum Pressure ◽

Chamber Pressure ◽

Asymmetric Structure ◽

The Impact

A vacuum pressure tracking system with high-speed on-off valves is a discontinuous system due to the discrete nature of high-speed on-off valves. Chamber pressure changes in the system are determined by the mass flow rates during the processes of charging and discharging. Here, a sliding mode controller with an asymmetric compensator based on average mass flow rate is designed for accurate vacuum pressure tracking. The controller output signal is converted into the duty cycles of the high-speed on-off valves via a pulse width modulation pulsing scheme. Owing to the extreme asymmetry of the processes, an asymmetric structure comprising one high-speed on-off valve in the charging unit and three high-speed on-off valves in the discharging unit is applied to weaken the impact of asymmetry. In addition, an asymmetric compensator is also designed to modify the pulse width modulation pulsing scheme to further eliminate the asymmetry. Experimental results indicate that the proposed controller achieves better performance in pressure tracking with the asymmetric compensator overcoming process asymmetry and enhancing system robustness.

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