The direct power control of three-phase AC-DC converter under unbalance voltage condition

This paper has presents the integrated approach for three-phase PWM AC-DC converter for obtaining the symmetrical components under unbalanced supply condition. The input structures for conventional direct power control have been modified with three simpler sequence networks instead it coupled by a detailed three-phase system method. In the cases of an unbalanced three-phase system, it causes the presence of unbalanced current and voltages thus produce the negative components on the grid voltage. Otherwise, the unbalance voltage in a three-phase power system causes severe performance degradation of a grid-connected VSI. Therefore, the imbalance voltage can be resolved by separating from the individual elements of voltage and current into symmetrical components called as a sequencing network. Consequently, the input power is relatively improved during unbalanced condition. It proven through the measurement of Total Harmonic Distortion (THD) from the conventional direct power control in individual elements is much higher compared than it resolved in separate components. Therefore, three symmetrical components are necessary for imbalance supply condition to obtaining almost sinusoidal grid currents

A CONVERSION OF ICE SYSTEM INTO ELECTRIC VEHICLE

Nowadays, an electric vehicle (EV) is increasingly popular among researchers and professionals due to greenhouse gas emission issues and energy supply shortage in coming years. However, the development of the EV through conversion method is still cloudy to general peoples. This paper depicts the development of converting the commercial internal combustion engine (ICE) based donor vehicle into the electric vehicle while retaining its original transmission. The aim is to provide the minimum step of conversion process without ignoring the safety aspect. The conversion method is described step-by-step to provide better understanding to the reader. The conversion process begins with the disassembling of combustion engine while the transmission box is remained in place. The electric motor-transmission coupling plates which consist of inner and outer parts are designed as accurate as possible based on the shape and measurement of both shaft and chassis. The controller unit is the heart and brain of the EV will do all the heavy lifting by interlink the batteries with the electric motor. The batteries that consist of several Lithium Polymer (LiPo) cell will provide all the energy to power up the controller and to drive the electric motor. The interaction between this three components (batteries, controller and electric motor) as well as safety issue is thoroughly elaborated. At the end, the performances of completed EV with high acceleration rate is analyzed and presented

Analysis of direct power control AC-DC converter under unbalance voltage supply for steady-state and dynamic response

This paper presents an analysis of Direct Power Control (DPC) technique for the Three-Phase Pulse Width Modulation (PWM) AC-DC converter under unbalanced supply condition. Unbalance condition will cause the presence of unbalanced current and voltages thus produce the negative components on the grid voltage as well as severe performance degradation of a grid connected Voltage Source Inverter (VSI). The input structures for conventional DPC has been modified with a three simpler sequence networks instead of coupled by a detailed Three-Phase system method. The imbalance voltage can be resolved by separating from the individual elements of voltage and current into symmetrical components called Sequence Network. Consequently, the input power relatively improved during unbalanced condition almost 70% through the measurement of Total Harmonic Distortion (THD) from the conventional Direct Power Control (DPC) in individual elements which is higher compared to separate components. Hence, several analyses are performed in order to analyze the steady state and dynamic performance of the converter, particularly during the load and DC voltage output reference variations

Analysis Of Multiphase Transformer Supplying A Static And Dynamic Load

Transformers are able to step up or step down an output voltage from their input. It also can be used to directly supply an electrical motor when a constant frequency operation is required. Here, the research is focusing on designing a three-to-five phase transformer that acts as static phase converters for supplying a balance five-phase load. The designing process of the transformer is described based on the graphical phasor diagram that is flexible and easy to be implemented. At the end, the performances of the designed transformer are evaluated using a static and dynamic load. The designed three-to-five phase transformer is able to maintain a balance five phase voltage for several type and level of load as shown in experimental result