• 전력전자학회:학술대회논문집
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• 전력전자학회 2000년도 전력전자학술대회 논문집
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• pp.413-416
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• 2000

본논문에서는 유도전동기 속도 및 토크 제어시 고조파의 왜형률을 감소시키고 디지털 구현이 용이하며 선형제어 영역을 증가시킬 수 있는 스위칭 방식으로 Space voltage Vector PWM(Pulse Width Modulation) 설명하였으며 시뮬레이션하기 위한 user_tool로써 Matlab/Simulink를 이용하여 SVPWM을 구현하는 방법을 설명하였다 결과적으로 개루프 운전 시 유도기에 인가되는 기준전압을 각각 비과변조와 과변조 시 전압비율 변경방식을 사용하여 나타나는 응답으로 가상스위칭 시간 T1, T2, T0 와 속도, 상전류, 토크응답을 알아보았다.

• Journal of Power Electronics
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• 제15권6호
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• pp.1524-1532
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• 2015

Conventional space vector pulse width modulation based asymmetrical dual inverter configuration produces high common mode voltage (CMV) variations. This CMV causes the flow of common mode current, which adversely affects the motor bearings and electromagnetic interference of nearby electronic systems. In this study, a simple and generalized carrier based pulse width modulation (PWM) technique is proposed for dual inverter configuration. This simple approach generates various continuous and discontinuous modulating signals based PWM algorithms. With the application of the discontinuous modulating signal based PWM algorithm to the asymmetrical dual inverter configuration, the CMV can be reduced with a slightly improved quality of output voltage. The performance of the continuous and discontinuous modulating signals based PWM algorithms is explored through both theoretical and experimental studies. Results show that the discontinuous modulating signal based PWM algorithm efficiently reduces the CMV and switching losses.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2002년도 전력전자학술대회 논문집
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• pp.308-312
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• 2002

In this paper, EPLD(Erasable Programmable Logic Device) based induction motor drives with a SRP-PWM(Separatley Randomized Pulse Position PWM) is proposed. In the proposed RPWM (Random PWM), each of three phase pulses is located randomly in each switching interval. Based on the space vector modulation technique, the duty ratio of the pulses is calculated. To verify the validity of the proposed RPWM, the experimental study was tried. Along with the randomization of PWM pulses, the space vector modulation is also executed in the TMS320C31 DSP(Digital Signal Processor). The experimental results show that the voltage and switching noise harmonics are spread to a wide band area. Also, the performance of the proposed SRP-PWM and the conventional SVM-PWM are nearly the same from the viewpoing of the v/f constant control.

• Journal of Power Electronics
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• 제5권2호
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• pp.142-150
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• 2005

This paper presents a systematic approach to study the carrier based pulse width modulation (PWM) techniques applied to diode-clamped and cascade multilevel inverters by using multi-modulating patterns. This method is based on the description of controllable redundant parameters in the modulating signals. A unified mathematical formulation is presented for carrier based PWM methods, which obtains outputs similar to the corresponding space vector PWM. A full and separate control of the fundamental voltage, vector redundancies and phase redundancies can be obtained in the carrier based PWM. In this paper, the proposed PWM method and corresponding algorithm for generating multi-modulating signals will be formulated and demonstrated by our simulations.

• Journal of Electrical Engineering and Technology
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• 제9권2호
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• pp.489-500
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• 2014

This paper presents a simple modified unipolar carrier-based pulsewidth modulation (CB-PWM) strategy for the three-level neutral-point-clamped (NPC) voltage source inverter (VSI). Analytical expressions for the relationship between modulation reference signals and output voltages are derived. The proposed modulation technique for the three-level NPC VSI includes the maximum and minimum of the three-phase sinusoidal reference voltages with zero-sequence voltage injection concept. The proposed modified CB-PWM strategy incorporates a novel method that requires only of one triangular carrier wave for generate the gating pulses in three-level NPC VSI. It has the advantages of being simplifying the algorithm with no need of complex two/multi-carrier pulsewidth modulation or space vector modulation (SVM) and it's also simple to implement. The possibility of the proposed CB-PWM technique has been verified though computer simulation and experimental results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 A
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• pp.265-269
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• 1994

The switching dead time avoiding a bridge leg short circuit in PWM voltage source inverter produces distortions of the controlling inverter output performance such as current waveform, voltage vector, and torque. In this paper, the influence of dead time is investigated. The on-line space voltage vector modulation method is used for current controller. It is possible to compensate dead time by space voltage vector modulation which generates additional pulse compensating voltage distortion caused by dead time. In addition, narrow pulse which is generally neglected can be compensated. All the algorithms, including field-oriented control are performed by one chip microprocessor 80C196MC and DSP TMS320C31. Experimental results probe that the proposed scheme provides a good inverter output performance.

• Journal of Power Electronics
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• 제17권1호
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• pp.88-95
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• 2017

To reduce common-mode voltage (CMV), various reduced CMV pulse width modulation (RCMV-PWM) algorithms have been proposed, including active zero state PWM (AZSPWM) algorithms, remote state PWM (RSPWM) algorithms, and near state PWM (NSPWM) algorithms. Among these algorithms, AZSPWM algorithms can reduce CMV, but they increase the number of switchings compared to the conventional space vector PWM (CSVPWM). This paper presents a new AZSPWM algorithm for reductions in both the CMV and total number of switchings in BLAC motor drives. Since the proposed AZSPWM algorithm uses only active voltage vectors for motor control, it reduces CMV by 1/3 compared to CSVPWM. The proposed AZSPWM algorithm also reduces the total number of switchings compared to existing AZSPWM algorithms by eliminating the switchings required from one sector to the next. The performance of the proposed algorithm is verified by analyses, simulations, and experimental results.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제51권7호
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• pp.387-398
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• 2002

In this paper, a new Three-Phase Lead-Lag Random Pulse Position PWM(LL-RPWM) scheme is proposed and implemented for decreasing audible acoustic noise of motor drives. In the proposed RPWM(Random PWM), each of three phase pulses is located randomly in each switching interval. Based on the space vector modulation technique, the duty ratio of the pulses is calculated. Along with the randomization of the PWM pulses, we can obtain the effects of spread spectra of voltage, current as in the case of randomly changed switching frequency. To verify the validity of the proposed LL-RPWM, the simulation and experimental study was tried. Along with the randomization PWM pulses, the space vector modulation is also executed in the C167 micro-controller. The simulation and experimental results show that the voltage and current harmonics are spread to a wide band area and that the audible acoustic noise is reduced by the proposed RPWM method.

• Journal of Power Electronics
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• 제16권1호
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• pp.388-397
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• 2016

An error-compensated pulse width modulator (ECPWM) is proposed to improve the baseband harmonic performance and the switching loss of voltage source inverters (VSIs). Selecting between harmonic distortion and switching loss is a design tradeoff in the conventional space vector pulse width modulation. In this work, an accumulated difference in produced and desired phase voltages is considered to adjust the reference signal. This mechanism can compensate for the voltage error in the previous carrier period. With error compensation every half-carrier period, the proposed ECPWM allows one-half reduction in carrier frequency without scarifying baseband harmonic distortion. The proposed modulator is applied to a three-phase VSI with R-L load and a motor-speed-control system for experiments. The measured efficiency and operating temperature of switches confirm the effectiveness of the proposed scheme.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2016년도 추계학술대회 논문집
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• pp.230-231
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• 2016

본 논문은 공간벡터 변조 방법에서부터 Six-step 동작까지의 새로운 과변조 방법을 제시하였다. 극전압을 푸리에 시리즈를 이용하여 분석하였고 지령 상전압에서부터 펄스 폭 변조 스위칭 신호까지의 알고리즘을 제안하였다. Matlab 시뮬레이션을 통해 검증하였다.