• Journal of Power Electronics
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• v.18 no.6
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• pp.1819-1829
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• 2018

A three-phase, three-switch, and three-level boost-type PWM rectifier (Vienna rectifier) is proposed as an active front-end power factor correction (PFC) rectifier for telecom loads. The proposed active front-end PFC rectifier system is modeled by the switching cycle average model. The relation between duty ratios and DC link capacitor voltages is derived in terms of the system input currents. Furthermore, the feasible switching states are identified and applied to the proposed system to reduce the switching stress and DC ripples. A detailed equivalent circuit analysis of the proposed front-end PFC rectifier is conducted, and its performance is verified through simulations in MATLAB. Simulation results are verified using an experimental setup of an active front-end PFC rectifier that was developed in the laboratory. Simulation and experimental results demonstrate the improved power quality parameters that are in accordance with the IEEE and IEC standards.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.3
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• pp.355-364
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• 2013

Respect to the input AC voltage and output DC voltage, conventional three-phase PWM rectifier is classified as the voltage type rectifier with boost capability and the current type rectifier voltage with buck capability. Conventional PWM rectifier can not at the same time the boost and buck capability and its bridge is weak in the shoot- through state. These problems can be solved by Z-source PWM rectifier which has all characteristic of voltage and current type PWM rectifier. By shoot-through duty ratio control, the Z-source PWM rectifier can buck and boost at the same time, also, there is no need to consider the dead time. This paper proposes the input AC voltage sensorless control method of a three-phase Z-source PWM rectifier in order to accomplish the unity input power factor and output DC voltage control. The proposed method is estimated the input AC voltage by using input AC current and output DC voltage, hence, the sensor for the input AC voltage detection is no needed. comparison of the estimated and detected input AC voltage, estimated phase angle of the input voltage, the output DC voltage response for reference value, unity power factor, FFT(Fast Fourier Transform) of the estimated voltage and efficiency are verified by PSIM simulation.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.48 no.8
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• pp.440-447
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• 1999

This paper proposes a control method for three-phase PWM rectifier with only single current sensor in DC link side. A PWM modulation strategy for reconstructing three phase currents from the DC link current is given. The states of the retifier switch are modified so that all phase currents can be reconstructed in a switching period although one or two of active vectors is applied only for a short time. Therefore, a new current control using an adjustment scheme of the modulation signal for three-phase PWM rectifier will be discussed, and verified the experimental results.

• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.19-21
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• 2007

This paper proposes an input waveform improvement using VIENNA Rectifier(three-phase/level/switch). VIENNA Rectifier is based on the combination of a three-phase diode bridge and dc/dc converter. It features low input current ripple and sinusoidal mains current form.

• Proceedings of the KSR Conference
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• 1999.05a
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• pp.328-335
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• 1999

Three phase full bridge rectifier has been used to obtain dc voltage from three phase ac voltage source. The rectifier system has drawbacks that power factor is low and power flow is unidirectional. Therefore, when dc voltage increases due to regeneration of power the dynamic resister for dissipation of regeneration power must be installed. But three phase PWM converter can be controlled to operate with unity power factor and bidirectional power flow. Therefore when the PWM converter is used as do supply system, the dissipating resistor is not necessary. On this thesis, in order to design a controller having good performance, the hee phase PWM converter is completely modeled by using circuit DQ-transformation and thus a general and simple instructive equivalent circuit is obtained; the inductor set becomes a second order gyrator-coupled system and three phase inverter becomes a transformer as well. Under given phase angle(${\alpha}$) and modulation index(MI) of the three phase inverter, the dc and ac characteristics are obtained by analysis of the transformed equivalent circuit The validity of the equivalent circuit is confirmed through PSPICE simulation. And based on the dc and ac characteristics a controller with unity power factor is proposed.

• Journal of Power Electronics
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• v.12 no.4
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• pp.559-566
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• 2012

A new design method for the LCL filters of three-phase voltage source PWM rectifiers is presented in this paper. Based on the single-phase harmonic equivalent model, the harmonic voltage of the rectifier side is calculated to design the LCL filter parameters by an iterative algorithm, in which the resonance frequency $f_{res}$ and the ratio r between the grid-side inductance and the rectifier-side inductance are selected as known constants. The design criteria and process are introduced and the influence on the design result by the value of the resonance frequency $f_{res}$, ratio r is analyzed. Finally an example (600V, 500kW) is tested by simulation and experiment to verify the validity of the new design method.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.36 no.2
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• pp.107-113
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• 1987

A complete design of a new digital control circuit for a three-phase controlled rectifier is presented. The circuit consists of a gating signal generating ROM, down counter and adder. Proposed scheme is simple and quite adequate to the microprocessor-based digitally controlled systems. The basic principle and operation characteristics of the circuit are described and experimental-results show good dynamic performance. Synchronization problem with noisy reference is also discussed. The basic phylosophy developed can be extended to the other phase control system, e.g., cycloconverters, ac voltoge controllers, etc.

• The Transactions of the Korean Institute of Power Electronics
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• v.6 no.4
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• pp.348-361
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• 2001

The three-phase diode rectifier with capacitive filter is highly sensitive to line voltage unbalance. Because of its inherent nonlinear characteristics, small line voltage unbalance may cause highly unbalanced line current, causing detrimental effects on power quality. This paper presents a theoretical basis on this 'unbalance amplification effect' and derives an analytical model of line current characteristics under unbalanced line voltage condition for various modes of operation. The results provide a basic guideline for optimal design of a three-phase diode rectifier with capacitive filter that is most commonly used for interfacing various power conversion equipments to power lines.

• Journal of Power Electronics
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• v.19 no.1
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• pp.288-295
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• 2019

Rectifiers are widely used in industrial applications. Although detailed models of rectifiers are usually used to evaluate their performance, they are complex and time-consuming. Therefore, the Average Value Model (AVM) has been introduced to meet the demand for a simple and accurate model. This type of rectifier modeling can be used to simplify the simulations of large systems. The AVM of diode rectifiers has been an area of interest for many electrical engineers. However, healthy diode rectifiers are only considered for average value modeling. By contrast, faults occur frequently on diodes, which eventually cause the diodes to open-circuit. Therefore, it is essential to model bridge rectifiers under this faulty condition. Indeed, conventional AVMs are not appropriate or accurate for faulty rectifiers. In addition, they are significantly different in modeling. In this paper, a novel application of the parametric average value of a three-phase line-commutated rectifier is proposed in which one diode of the rectifier is considered open-circuited. In order to evaluate the proposed AVM, it is compared with experimental and simulation results for the application of a brushless synchronous generator field. The results clearly demonstrate the accuracy of the proposed model.

• Proceedings of the KIEE Conference
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• 1997.07f
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• pp.2237-2239
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• 1997

The conventional three phase rectifier with Bulk LC output filter has been widely used in the industry because of simple circuit, low cost and high power factor (90%). One of the biggest drawback of this rectifier is bulky and havy. This is serious especially for aerospace applications. To solve this problem a new simple rectifier is presented. Operation of the proposed rectifier is illustrated and verifyed by PSpice simulation.