Dual frame control scheme with a plug-in frequency domain based repetitive controller for three phase PWM boost rectifier under distorted and unbalanced supply voltages

In this paper, a proposed control strategy is presented to improve the performance of the pulse width modulation (PWM) boost type rectifier when operating under different supply voltage conditions (balanced, unbalanced, and distorted three-phase supply voltages). The proposed control strategy is divided into two parts, the first part is voltage controller and the second part is current controller. In the voltage controller, Repetitive Controller (RC) is used to reduce the even order harmonics in the regulated output dc voltage so small output capacitor (filter) is used instead of large capacitor. RC also reduces the even order harmonics which appear in the reflected dc current (IMAX), this leads to reduce the odd order harmonics which appear in the input currents. While in the current controller, Enhanced Phase Locked Loop (EPLL) technique is used to obtain sinusoidal and balanced three phases, to construct the reference currents, which are in phase with the fundamental supply voltages. Therefore, the supply-side power factor is kept close to unity. A proportional controller is used to give excellent tracking between the line and the reference currents. The complete system with the proposed control strategy are simulated using Matlab/Simulink. The results for the complete system using repetitive voltage controller are obtained and compared to the results of the system with the conventional voltage controller (Proportional-Integral (PI) controller connected in series with a Low Pass Filter (LPF)). The results with the repetitive controller show better response and stable operation in the steady state under different input voltage conditions, as well as in the transient response under changing the load condition.

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Hierarchical Control Scheme for Droop Controlled Parallel Three Phase Voltage Source Inverters in Low Voltage AC MicroGrid

International Review of Automatic Control (IREACO) ◽

10.15866/ireaco.v9i5.9903 ◽

2016 ◽

Vol 9 (5) ◽

pp. 279 ◽

Cited By ~ 3

Author(s):

El Hassane Margoum ◽

Nissrine Krami ◽

Luis Seca ◽

Carlos Moreira

Keyword(s):

Low Voltage ◽

Hierarchical Control ◽

Voltage Source ◽

Phase Voltage ◽

Voltage Source Inverters ◽

Three Phase ◽

Control Scheme ◽

Ac Microgrid

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Analysis of Three-Phase Wye-Delta Connected LLC

Energies ◽

10.3390/en14123606 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3606

Author(s):

Jing-Yuan Lin ◽

Chuan-Ting Chen ◽

Kuan-Hung Chen ◽

Yi-Feng Lin

Keyword(s):

Frequency Domain ◽

Time Domain ◽

Operation Time ◽

Time Domain Analysis ◽

Domain Analysis ◽

Frequency Domain Analysis ◽

Complete Analysis ◽

Plane Analysis ◽

Analysis Methods ◽

Three Phase

Three-phase wye–delta LLC topology is suitable for voltage step down and high output current, and has been used in the industry for some time, e.g., for server power and EV charger. However, no comprehensive circuit analysis has been performed for three-phase wye–delta LLC. This paper provides complete analysis methods for three-phase wye–delta LLC. The analysis methods include circuit operation, time domain analysis, frequency domain analysis, and state–plane analysis. Circuit operation helps determine the circuit composition and operation sequence. Time domain analysis helps understand the detail operation, equivalent circuit model, and circuit equation. Frequency domain analysis helps obtain the curve of the transfer function and assists in circuit design. State–plane analysis is used for optimal trajectory control (OTC). These analyses not only can calculate the voltage/current stress, but can also help design three-phase wye-delta connected LLC and provide the OTC control reference. In addition, this paper uses PSIM simulation to verify the correctness of analysis. At the end, a 5-kW three-phase wye–delta LLC prototype is realized. The specification of the prototype is a DC input voltage of 380 V and output voltage/current of 48 V/105 A. The peak efficiency is 96.57%.

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