Taufik

A new AC-DC converter using bridgeless SEPIC

A new bridgeless power factor correction circuit (PFC) based on single ended primary inductance converter (SEPIC) is proposed. The number of component conducted at each subinterval mode is reduced compared to the existing topologies. Analysis of the converter operated in discontinuous-conduction mode (DCM) is discussed. Experimental circuit for the proposed converter is developed with universal input voltage capability for 50V DC output voltage connected to 100W load. The simulation and experimental results are presented to show the performances of the proposed circuit.

A parallel energy-sharing control for fuel cell-battery-ultracapacitor hybrid vehicle

This paper proposes a parallel energy-sharing control for fuel cell hybrid vehicles (FCHVs) application. The hybrid source consists of fuel cells (FCs) stack, battery packs and Ultracapacitor (UC) modules. In the proposed parallel energy sharing control, each source is connected to a DC bus via power electronics converters. A total of six control loops are applied in the supervisory system in order to regulate the DC bus voltage, control of power flow and at the same time to monitor the state of charge (SOC) of each energy storage device. Simulation with experiment verifications are carried out to verify the proposed energy control system.

Online Learning Neural Network Control of Buck-Boost Converter

This paper proposes a neural network control scheme of a DC-DC buck-boost converter using online learning method. In this technique, a back propagation algorithm is derived. The controller is designed to stabilize the output voltage of the DC-DC converter and to improve performance of the Buck-Boost converter during transient operations. Furthermore, to investigate the effectiveness of the proposed controller, some operations such as starting-up and reference voltage variations are verified. The numerical simulation results show that the proposed controller has a better performance compare to the conventional PI-Controller method.

Performance study of Series Loaded Resonant converter using super barrier rectifiers

In power electronics efficiency improvement is constantly being sought out through venues such as improved topologies or improved devices. Series Loaded Resonant (SLR) DC-DC converter is a type of soft-switching topology widely known for providing improved efficiency. This paper investigates the efficiency and transient performance of SLR when a new type of diode called Super Barrier RectifierTM is being used. The design of SLR, results from computer simulations, and hardware measurements will be discussed. The efficiency measurements from all conduction modes in SLR using three types of diodes (pn, schottky, and SBR) will be presented along with transient study of one of SLRs continuous conduction mode.

Development of wind tunnel for laboratory wind turbine testing

This paper presents the development of a wind tunnel that will be used for wind turbine testing in a controlled environment. The prototype is designed to be able to provide wind speeds of up to 20 m/s (∼43mph) depending on the cross sectional area of the tunnel chamber. A 42 inch tube axial fan is driven by a 5hp induction motor using a variable frequency drive to allow continuously variable wind speeds from near zero up to the maximum wind speed. The fan is rated to produce ∼25,000 CFM and the corresponding wind speed is therefore dependent on chamber cross sectional area. There will be two chamber sizes possible. One is 2.5 feet by 2.5 feet and the other is 3.25 feet by 3.25 feet. The larger cross section allows larger turbines to be tested while the smaller cross section allows higher wind speeds to be reached. The paper also describes some possible applications of the apparatus in the academic environment.

A new multiphase multi-interleaving buck converter with bypass LC

As the number of transistors in microprocessors increases, their power demand increases accordingly. This poses design challenges for their power supply module called VRM (Voltage Regulator Module) especially when operated at sub voltage range. This paper presents the design of a new multiphase multi-interleaving topology that addresses these challenges. A lab scaled hardware prototype of the new topology shows improved load regulation, output voltage ripple and dynamic response time compared to a commercially available power supply module.

Harmonic analysis of input current of single- phase controlled bridge rectifier

Harmonic analysis of input current of single phase uncontrolled rectifier is widely known. However, little has been known about harmonic of the input current of single phase controlled or thyristor rectifier. This paper presents such an analysis using the bridge configuration for the controlled rectifier circuit. Results obtained from mathematical derivation, computer simulation, and hardware measurements will also be discussed.

Multiphase Interleaving Buck Converter with Input-Output Bypass Capacitor

As the number of transistors in microprocessors increases per Moore’s Law their power requirement increases accordingly. This poses design challenges for their power supply module especially when microprocessors operate at sub voltage range. This paper presents a new multiphase topology that addresses these challenges. Laboratory tests on a hardware prototype of the topology shows improved performance compared to a commercially available power supply module.

The DC House project: An alternate solution for rural electrification

The DC House project started in 2010 which aims to provide an alternative solution to rural electrification, especially for geographically hard-to-reach areas. The DC House offers an individual or family-based as opposed to the community-based rural electrification. This makes the DC House solution scalable, affordable, and flexible. It does this by operating its components and system based on low-power, low-voltage DC electrical system to directly run DC loads; thus, bypassing losses associated with the traditional AC voltage system. The DC House also uses human-powered energy sources, making it even more sustainable in producing electricity. The development of the DC House system along with its components will be presented. Recent status of the DC House including the various projects undertaken to construct it and plans for its field testing will also be summarized.

Harmonics and Dynamic Response of a Virtual Air Gap Variable Reactor

As more sustainable energy generation is integrated into power grid, the control of power flow in an efficient and effective manner becomes more and more essential. A new innovative device is presented that allows the control of line power flow without the high harmonics and efficiency losses of traditional methods. This paper presents the dynamic response and the harmonics of a laboratory prototype Virtual Air Gap Variable Reactor (VAG-VR) and compares them with those of a thyristor controlled reactor (TCR). Variable Reactors have many applications in the power industry. Their use allows control of line power flow, voltage regulation, as well as damping of power oscillations and sub synchronous resonances. A variable reactor is most commonly implemented as a TCR by switching in and out a constant reactance to achieve an averaged variable reactance. By using a virtual air gap, implementation of a continuously variable reactance is possible with a better dynamic response and without introducing the harmonics created by the thyristor switching of a TCR.