• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.1
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• pp.58-69
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• 2016

This paper describes the design and implementation of a new diode clamped multilevel inverter for variable frequency drive. The diode clamp multilevel inverter has been widely used for low power, high voltage applications due to its superior performance. However, it has some limitations such as increased number of switching devices and complex PWM control. In this paper, a new topology is proposed. New topology requires only (N-1) switching devices and (N-3) clamping diodes compared to existing topology. A modified APO-PWM control method is used to generate gate pulses for inverter. The proposed inverter topology is coupled with single phase induction motor and its performance is tested by MATLAB simulation. Finally, a prototype model has built and its performance is tested with single phase variable frequency drive.

• Proceedings of the KIPE Conference
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• 2001.12a
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• pp.185-189
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• 2001

This paper presents a precision voltage control technique of a single phase PWM inverter for a constant voltage and constant frequency(CVCF) applications. The proposed control employes a PLL compensating loop which minimize the steady state error and phase delay. The computer simulation and experiment are carried out for the actual single phase PWM inverter and the results well demonstrate the effectiveness of the proposed control.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.5
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• pp.29-36
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• 2010

In this paper, we propose a single-phase inverter system using new modulation method. The proposed system is composed of a buck-boost converter and an inverter and controlled by PWAM scheme. PWAM method is a new modulation method which is the incorporation of PWM(Pulse Width Modulation) and PAM(Pulse Amplitude Modulation) methods. The DC voltage which is the input voltage of buck-boost converter is converted into a variable DC voltage by buck-boost converter. Also, the variable DC voltage which is the output voltage of buck-boost converter is converted into a sinusoidal AC voltage by inverter. The input voltage of inverter is processed by PWM switching in PWM section and bypassed in PAM section. By using PWAM method, switching action is not existed in PAM section and thus the times of switching is reduced. As a result, the switching loss can be reduced.

• Journal of IKEEE
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• v.26 no.4
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• pp.584-589
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• 2022

For DC-AC power conversion from a high-voltage photovoltaic panel to a single-phase grid, the two-stage transformerless inverter with a buck-boost converter followed by a full-bridge inverter is widely used. To avoid an excessive leakage current due to the large parasitic capacitance of the photovoltaic panel, the full-bridge inverter can only adopt the bipolar PWM which results in much higher power loss compared to the unipolar PWM. In order to overcome such a poor efficiency, this paper proposes a new topology in which an IGBT and a diode for circuit isolation are added to the buck-boost converter. The proposed circuit isolation method allows the unipolar PWM in the full-bridge inverter without any increase in the leakage current so that the overall efficiency can be improved. The validity of the proposed solution is verified by computer simulation and power loss calculation.

• The Transactions of the Korean Institute of Power Electronics
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• v.21 no.1
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• pp.27-33
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• 2016

A pulse-width modulation (PWM) method for common mode noise reduction in a PWM inverter connected to a single-phase grid is proposed in this study. The extensively used conventional switching method may experience common mode voltage problems, which generate current leakage and electromagnetic induction problems. In the proposed switching method, the neutral point of the output voltage is always fixed at both ends of the input voltage to reduce common mode noise. The validity of the proposed method is proven through simulation and experimental results.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.67 no.2
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• pp.82-89
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• 2018

This paper presents a novel prototype of dual mode control based phase shift ZVS PWM high frequency load resonant inverter with lossless snubber capacitors in addition to a single active auxiliary resonant snubber for electromagnetic induction heating(IH) foam metal based consumer fluid dual packs(DPA) heater. The operating principle in steady state and unique features of this voltage source soft switching high frequency inverter circuit topology are described in this paper. The lossless snubber and auxiliary active resonant snubber assisted constant frequency phase shift ZVS PWM high frequency load resonant inverter employing IGBT power modules actually is capable of achieving zero voltage soft commutation over a widely specified power regulation range from full power to low power. The steady state operating performances of this dual mode phase shift PWM series load resonant high frequency inverter are evaluated and discussed on the basis of simulation and experimental results for induction heated foam metal heater which is designed for compact and high efficient moving fluid heating appliance in the consumer pipeline systems.

• Journal of Power Electronics
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• v.12 no.4
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• pp.548-558
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• 2012

In this paper, a novel offset-based single-state pulse width modulation (PWM) method for achieving zero common-mode voltage (CMV) and reducing switching losses in multilevel inverters is presented. The specific active switching state of the zero common-mode (ZCM) voltage that approximates the reference voltage can be deduced from the switching state sequence of the reduced CMV phase disposition PWM (CMV PD PWM) method. From the reference leg voltages for the zero common-mode voltage, an N-to-2-level transformation defines a virtual two-level inverter and the corresponding nominal leg voltage references. The commutation process of the reduced CMV PD PWM method in a multilevel inverter and its outputs can be simply followed in a nominal switching time diagram for the virtual inverter. The characteristics of the reduced CMV PD PWM and the single-state PWM for zero common-mode voltage are analyzed in detail in this paper. The theoretical analysis of the proposed PWM method is verified by experimental results.

• Journal of Power Electronics
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• v.11 no.3
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• pp.285-293
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• 2011

This paper proposes two SRM driving systems using a variable dc-link voltage controlled by a single-phase inverter. Two SRM converter topologies of a half bridge type and a full bridge type are proposed according to the power circuits of an inverter. The phase current can be controlled by means of a PWM controller at the inverter, and the turn-on/off angle at the phase switches can be controlled by a position sensor at the converter in the drive system. The inverter acts as a peak-current limiter if the transient current exceeds its maximum value. SRMs using the proposed topologies maintain high efficiency due to energy regeneration after the turn-off of power switches. The operational modes of the proposed topologies are verified by simulation and experimental results.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.11
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• pp.33-41
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• 2014

This paper is research result for a development of sapphire silicon ingot glowing(SSIG) PWM converter system for 80kW 10kA. The system include 3-phase AC-DC diode rectifier of input voltage AC 380V and 60Hz, DC-AC single phase full bridge PWM inverter of high frequency, AC-DC single-phase full wave rectifier using center-tapped of transformer for low voltage 8.0V and large current 10,000A of output specification, tungsten resistor load 0.1[$m{\Omega}$]. PWM switching frequency for IGBT inverter control set 30kHz. The suggested researching contents are designed data sheets of power converter system, PSIM simulation, operating characteristics and analysis results of developed SSIG system. This paper propose

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.553-557
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• 2000

This paper proposes the method to reduce output leakage current in single phase induction motor driven a PWM inverter. A proposed method applies to a new PWM switching algorism to reduce low-order harmonic in an inverter system with a feedback circuit of leakage current. Simulation is done to confirm a validity of method Proposed.