• 전기학회논문지
• /
• 제60권11호
• /
• pp.2049-2055
• /
• 2011

In this paper a new current control method is proposed for the discontinuous conduction mode of boost converter. The proposed method using a current gain feedforward compensation adjusts a measured inductor current value and then, calculated an average current precisely in the discontinuous conduction mode as well as continuous conduction mode. By applying the proposed method, the current measurement error is significantly reduced to 2% regardless of the operating points. The proposed method is analyzed and its performance is investigated in simulation. To verify the feasibility of the proposed scheme, a 10kW 3-phase interleaved boost converter was built and experimental results are matched to the simulation results.

• 전력전자학회논문지
• /
• 제22권3호
• /
• pp.231-239
• /
• 2017

A novel current control technique with fast response and application in an unbalanced system is proposed in this paper. Contrary to the conventional PI and dead-beat current control techniques, the proposed method is adopted to the valley current mode control (VCMC) and average current mode control (ACMC) methods to overcome the phase delay caused by conventional methods. The advantages of the proposed system are simplicity of structure and ease of implementation. The VCMC and ACMC methods are established and applied to the buck converter, boost converter, three-phase PWM converter, and three-phase inverter. The control performances of the proposed systems are shown by computer simulations and verified by experimental results.

• Journal of Power Electronics
• /
• 제19권1호
• /
• pp.201-210
• /
• 2019

This paper proposes a multimode hybrid control strategy that can achieve zero-voltage switching of primary switches and zero-current switching of secondary rectifier diodes in a wide input voltage range for full-bridge LLC resonant converters. When the input voltage is lower than the rated voltage, the converter operates in Mode 1 through the variable-frequency control strategy. When the input voltage is higher than the rated voltage, the converter operates in Mode 2 through the VF and phase-shift control strategy until the switching frequency reaches the upper limit. Then, the converter operates in Mode 3 through the constant-frequency and phase-shift control strategy. The secondary-side diode current will operate in the discontinuous current mode in Modes 1 and 3, whereas it will operate in the boundary current mode in Mode 2. The current RMS value and conduction loss can be reduced in Mode 2. A detailed theoretical analysis of the operation principle, the voltage gain characteristics, and the realization method is presented in this paper. Finally, a 500 W prototype with 100-200 V input voltage and 40 V output voltage is built to verify the feasibility of the multimode hybrid control strategy.

• 전기학회논문지P
• /
• 제58권1호
• /
• pp.20-26
• /
• 2009

In this paper, the switching mode conversion type pulse charger by fly-back converter method for lead battery of the solar cell generator equipment is proposed. And we propose the control circuit and design method of insulated switching mode convert type pulse charger by fly-back convert method in the lead battery. The proposed system can minimize the current consumption by digital pulse. Also the proposed system can generate the constant 10[KHz] frequency, transmit the signal with main control system in the power control system. And it supervises the state of lead battery using one chip micro processor. The proposed the switching mode conversion type pulse charger by the fly-back converter method can charge fast and stabilize lead battery with nominal value 12[V], 20[AH]. Also we propose the design procedure of the power control circuit for turn ratio of fly-back inductor and determining method of values such as the charging current, bulk current, partial current, over current value and fixed charging voltage. The experiment results for the voltage and current wave for partial, bulk, over and fixed charging period show the good charging effect and performance. And the PCB and internal coupling diagram of the switching mode conversion type pulse charger by fly-back converter method is presented.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1991년도 하계학술대회 논문집
• /
• pp.857-860
• /
• 1991

This paper describes a High-Speed 8-bit Current-Mode BiCMOS A/D Converter. The characteristics of this A/D Converter are as fellows. First, as ADC is operating in current-mode we can obtain the properties of increase of converting speed, low noise, and wideband. Second, the properties of high switching speed in bipolar transistor and of high packing density, low power consumption in MOS trnsistor are combined. Finally we reduce chip area by designing it with subranging mode and improve the converting speed by performing subtraction directly, which doesn't need D/A convertings, using current switching element. This converter is composed of two 4-bit ADC, current soure array which provides signal and reference current, current comparator and encoding network.

• Journal of Electrical Engineering and Technology
• /
• 제12권5호
• /
• pp.1970-1979
• /
• 2017

Ultra Lift Luo Converter (ULC) gained considerable research interest in recent years. The stability analysis of voltage mode and peak current mode controlled ULC in continuous conduction mode is analyzed in this paper. The Eigen value theory is used for the stability analysis of voltage mode controlled ULC. Then to characterize the dynamics of inner current loop, the expressions of closed loop transfer function and loop gain are determined. An algorithm has been developed to analyze the stability of the peak current mode controlled ULC. The theoretical results are correlated with the simulation results obtained using PSIM 9.1(SMARTCTRL 1.0) software. Finally it is proposed to fabricate a prototype and validate the performance by suitable experimental setup.

• 전력전자학회논문지
• /
• 제20권2호
• /
• pp.130-136
• /
• 2015

This study describes the structure and operation modes of vertical stabilization (VS) converter for international thermonuclear experimental reactor (ITER) and proposes a protection method. ITER VS converter supplies voltage (${\pm}1000V$)/current (${\pm}22.5kA$) to superconducting magnets for plasma current vertical stabilization. A four-quadrant operation must be achieved without zero-current discontinuous section. The operation mode of the VS converter is separated in 12-pulse mode, 6-pulse mode and circulation current mode according to the magnitude of the load current. Protection measures, such as bypass and discharge, are proposed for abnormal conditions, such as over current, over voltage, short circuit, and voltage sag. VS converter output voltage is controlled to satisfy voltage response time within 20 msec. Bypass operation is completed within 60 msec and discharge operation is performed successfully. The feasibility of the proposed control algorithm and protection measure is verified by assembling a real controller and implementing a power system including the VS converter in RTDS for a hardware-in-loop (HIL) facility.

• 전기학회논문지
• /
• 제58권2호
• /
• pp.301-307
• /
• 2009

In the paralleled converter module with peak current mode control, current imbalance appears when the voltage controllers with integral control of converter module are not exactly identical. In this paper, the voltage controller is designed to equal the current command of each converter module using the current command bus. The current balance controller is also proposed to balance the average currents of converter modules with imbalaced inductance. It is designed to have good transient response. Proposed method is implemented with the paralleled 2-module and 4-module boost converters with imbalanced inductance. Experimental results verify the performance of current share during both steady and transient states of converter.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2001년도 하계학술대회 논문집 B
• /
• pp.1052-1054
• /
• 2001

This paper describes a boost converter to be operated at the boundary of continuous current mode(CCM) and discontinuous current mode(DCM) for power factor correction and low cost. A control method to be utilized in simulation is a average-current mode method in case of operating in CCM. The simulation results show that Better is the CCM converter then the DCM converter in harmonic content and input current waveform. And A Double-boost converter is superior to single-boost converter for input-current harmonic.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 학술대회 논문집 전문대학교육위원
• /
• pp.14-16
• /
• 2004

This paper describes a boost converter to be operated at the boundary of continuous current mode(CCM) and discontinuous current mode(DCM) for power factor correction and low cost. A control method to be utilized in simulation is a average Current mode method in case of operating in CCM. The simulation results show that Better is the CCM converter then the DCM converter in harmonic content and input current waveform. And A Double-boost converter is superior to single-boost converter for input-current harmonic.