• 전력전자학회:학술대회논문집
• /
• 전력전자학회 1996년도 창립기념 전력전자학술발표회 논문집
• /
• pp.85-88
• /
• 1996

New power factor correction(PFC) technique based on the averaged model of boost converter is proposed. Without measurement of input current, power factor correction scheme derived from the averaged model is presented. With the measurements of input voltage and output voltage, the control signal is generated to make the shape of the line current same as the input voltage. The characteristics of input line current distortion is analyzed by considering the generation of duty cycle.

• 전기학회논문지
• /
• 제57권4호
• /
• pp.610-616
• /
• 2008

This paper presents a new robust sensorless control system for high performance induction motor drives fed by a matrix converter with variable structure. The lumped disturbances such as parameter variation and load disturbance of the system are estimated by a variable structure approach based on model reference adaptive scheme. A Reduced Order Extended Luenberger Observer(ROELO) is also employed to bring better responses at the low speed operation. Experimental results are shown to illustrate the performance of the proposed system.

• Journal of Power Electronics
• /
• 제12권1호
• /
• pp.113-119
• /
• 2012

This paper describes the design and control of a phase shift full bridge converter with a current doubler, which can be used for the on-board charger for the lead-acid battery of electric forklifts. Unlike the common resistance load, the battery has a large capacitance element and it absorbs the entire converter output ripple current, thereby shortening the battery life and degrading the system efficiency. In this paper a phase shift full bridge converter with a current doubler has been adopted to decrease the output ripple current and the transformer rating of the charger. The charge controller is designed by using the small signal model of the converter, taking into consideration the internal impedance of the battery. The stability and performance of the battery charger is then verified by constant current (CC) and constant voltage (CV) charge experiments using a lead-acid battery bank for an electric forklift.

• 동력기계공학회지
• /
• 제21권2호
• /
• pp.35-40
• /
• 2017

In this study, the multi-body dynamics model for a wave energy converter is established. The equations of motions for the mechanical parts of the wave energy converter are derived to analyze the dynamic behavior. A spring method with the same performance as the counter weight method is proposed. The counter weight method and spring method are analyzed for evaluating the performance of the wave energy converter. RecurDyn program which is a kind of commercial multi-body dynamics program is used to perform the dynamic simulation of the wave energy converter.

• Journal of Power Electronics
• /
• 제16권6호
• /
• pp.2016-2023
• /
• 2016

This paper presents a simple input-constrained current controller for a DC/DC boost converter with stability analysis that considers the nonlinearity of the converter model. The proposed controller is designed to satisfy the inherent input constraints of the converter under a physically reasonable assumption, which is the first contribution of this paper. The second contribution is providing a rigorous proof of the proposed control law, which keeps the closed-loop system along with the internal dynamics stable. The performance of the proposed controller is demonstrated through an experiment employing a 20-kW DC/DC boost converter.

• 전력전자학회논문지
• /
• 제20권6호
• /
• pp.573-579
• /
• 2015

A control algorithm of thyristor dual converter power system is proposed in this study for a railway power substation. The thyristor dual converter can use regenerative power without an additional system using control algorithm. An autonomous voltage and mode change method is also proposed to provide uninterrupted power to the railway. A 10 kW reduced model of the thyristor dual converter power system is built and tested to verify the validity of the proposed control algorithm.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2018년도 전력전자학술대회
• /
• pp.99-101
• /
• 2018

This paper present an input-series output-parallel active-clamp-forward converter for low voltage dc/dc xEV application. The converter can achieve ZVS turn-on for all switches. An accurate small signal model of the converter which includes the effect of leakage inductance is given and controller design based on modeling is described. Experimental and simulation results from a 3.2kW, 100kHz prototype are presented in order to verify the validity of the converter operation and the designed control parameters.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2001년도 전력전자학술대회 논문집
• /
• pp.491-495
• /
• 2001

Compare with diode or thyristor bridge AC/DC converter, the 3 phase PWM converter has some merits of low THD and unit power factor. So, in many critical application like as UPS, using PWM converter is the trends. 3 phase PWM converter had been studied widely already. But analytical design procedure can not found from publication for hardware design and controller design. So, in this paper, 3 phase PWM converter analysis review was given. And from the DC analysis result, parameter design was done. From the AC model, the voltage controller and current controller was designed. The gain of controllers was calculated by analytical method.

• 전기학회논문지
• /
• 제65권8호
• /
• pp.1400-1406
• /
• 2016

This paper presents a new adaptive converter control approach for electric motor systems whose voltage source is excited from photovoltaic (PV) power generators. First, an electric model is represented with dynamic states and output velocity of such DC motor systems. We propose a hybrid converter control law in which a state feedback control is applied as an auxiliary control framework. Moreover, control parameter estimation is derived to realize adaptive converter systems for effective control performance against stochastic PV power excitation in practice. We carry out stability analysis for such converter system by using a well-known eigenvalue theory. Lastly, numerical simulation is conducted to test reliability of the proposed converter control approach and prove its superiority in the control point of view.

• Transactions on Electrical and Electronic Materials
• /
• 제18권2호
• /
• pp.103-110
• /
• 2017

The number of applications of solar photovoltaic (PV) systems in power generation grids has increased in the last decade because of their ability to generate efficient and reliable power in a variety of low installation in domestic applications. Various PV converter topologies have therefore emerged, among which the modular multilevel converter (MMC) is very attractive due to its modularity and transformerless features. The modeling and control of the MMC has become an interesting issue due to the extremely large expansion of PV power plants at the residential scale and due to the power quality requirement of this application. This paper proposes a novel control method of MMC which is used to directly integrate the photovoltaic arrays with the power grid. Traditionally, a closed loop control has been used, although circulating current control and capacitors voltage balancing in each individual leg have remained unsolved problem. In this paper, the integration of model predictive control (MPC) and traditional closed loop control is proposed to control the MMC structure in a PV grid tied mode. Simulation results demonstrate the efficiency and effectiveness of the proposed control model.