Harmonic Distortion Caused by Single-Phase Grid-Connected PV Inverter

We propose a high-performance and robust control of a transformerless, single-phase PV inverter in the standalone mode. First, modeling and design of a DC-DC boost converter using a nonlinear back-stepping control was presented. The proposed converter uses a reference voltage that is generated by the Perturb and Observe (P&O) algorithm in order to extract the maximum power point (MPP) by responding accurately to varying atmospheric conditions. Another goal for using the boost converter is to raise the voltage at the input of the inverter without using a transformer in this system, thus making the system more compact and less expensive. Secondly, the single-phase H-bridge inverter was controlled by using back-stepping control in order to eliminate the error between the output voltage of the inverter and the desired value, even if there is acute load variation at the output of the inverter. The stability of the boost converter and H-bridge inverter was validated by using Lyapunov’s stability theory. Simulation results show that the proposed PV system with back-stepping controllers has a good extraction of the MPP with an efficiency of 99.93% and 1 ms of response time. In addition, the sinusoidal form of the output voltage of the inverter is fixed to 220 V and the total harmonic distortion of the output voltage was found to be less than 1%.

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A Review on Recent Advances and Future Trends of Transformerless Inverter Structures for Single-Phase Grid-Connected Photovoltaic Systems

Energies ◽

10.3390/en11081968 ◽

2018 ◽

Vol 11 (8) ◽

pp. 1968 ◽

Cited By ~ 20

Author(s):

Kamran Zeb ◽

Imran Khan ◽

Waqar Uddin ◽

Muhammad Adil Khan ◽

P. Sathishkumar ◽

...

Keyword(s):

Single Phase ◽

Semiconductor Device ◽

Harmonic Distortion ◽

Phase System ◽

Renewable Energy Resources ◽

Loss Analysis ◽

Pv Systems ◽

Pv Inverter ◽

Recent Developments ◽

And Control

The research significance of various scientific aspects of photovoltaic (PV) systems has increased over the past decade. Grid-tied inverters the vital elements for the effective interface of Renewable Energy Resources (RER) and utility in the distributed generation system. Currently, Single-Phase Transformerless Grid-Connected Photovoltaic (SPTG-CPV) inverters (1–10 kW) are undergoing further developments, with new designs, and interest of the solar market. In comparison to the transformer (TR) Galvanic Isolation (GI)-based inverters, its advantageous features are lower cost, lighter weight, smaller volume, higher efficiency, and less complexity. In this paper, a review of SPTG-CPV inverters has been carried out. The basic operational principles of all SPTG-CPV inverters are presented in details for positive, negative, and zero cycles. A comprehensive analysis of each topology has been deliberated. A comparative assessment is also performed based on weaknesses, strengths, component ratings, efficiency, total harmonic distortion (THD), semiconductor device losses, and leakage current of various SPTG-CPV inverters schemes. Typical PV inverter structures and control schemes for grid connected three-phase system and single-phase systems are also discussed, described, and reviewed. Comparison of various industrial grids-connected PV inverters is also performed. Loss analysis is also performed for various topologies at 1 kW. Selection of appropriate topologies for their particular application is thoroughly presented. Then, discussion and forthcoming progress are emphasized. Lastly, the conclusions are presented. More than 100 research publications on the topic of SPTG-CPV inverter topologies, configurations, and control schematics along with the recent developments are thoroughly reviewed and classified for quick reference.

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Synchronous Reference Frame Repetitive Control of a Single-Phase Three-Level Dual-Buck Photovoltaic Inverter

Electronics ◽

10.3390/electronics7100226 ◽

2018 ◽

Vol 7 (10) ◽

pp. 226 ◽

Cited By ~ 1

Author(s):

Jung-Yong Lee ◽

Younghoon Cho

Keyword(s):

Reference Frame ◽

Control Strategy ◽

Single Phase ◽

Harmonic Distortion ◽

Current Control ◽

Output Current ◽

Pv Inverter ◽

Synchronous Reference Frame ◽

Conduction Mode ◽

Repetitive Controller

This paper proposes a synchronous reference frame (SRF) control strategy for a single-phase, three-level, dual-buck photovoltaic (PV) inverter. The concept of virtual d-q transformation is adapted to the current control of the inverter, and the repetitive controller is implemented in the SRF. With the proposed control strategy, the memory allocation quantity for the repetitive controller is decreased and the capability of the current reference tracking is maximized. Thus, the proposed method significantly reduces the total harmonic distortion (THD) of the output current in both the continuous conduction mode (CCM) and the discontinuous conduction mode (DCM). In addition, the distortion of the output current is mostly composed of odd harmonics. Odd harmonic expressed to the even harmonic in SRF can be calculated using Park’s transformation. Therefore, a repetitive controller can improve dynamics by considering only even harmonic components in SRF rather than including all harmonics. The simulation and the experimental results verify the effectiveness of the proposed control strategy. The proposed method not only reduces the THD of the output current in both the CCM operation and the DCM operation, but also improves the dynamics of the current controller.

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An improved control method to suppress DC injection to the grid for grid-connected single-phase PV inverter with less harmonic distortion

2016 IEEE International Conference on Recent Trends in Electronics, Information & Communication Technology (RTEICT) ◽

10.1109/rteict.2016.7807949 ◽

2016 ◽

Cited By ~ 1

Author(s):

Abdul Wahab Ahmad ◽

Yunjian Peng ◽

Jionghong Chen ◽

Fangmo Han

Keyword(s):

Single Phase ◽

Control Method ◽

Harmonic Distortion ◽

Pv Inverter

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Multi-Point Time-Synchronized Waveform Recording for the Analysis of Wide-Area Harmonic Propagation

Applied Sciences ◽

10.3390/app10113869 ◽

2020 ◽

Vol 10 (11) ◽

pp. 3869 ◽

Cited By ~ 1

Author(s):

Stanislav Babaev ◽

Ravi Shankar Singh ◽

Sjef Cobben ◽

Vladimir Ćuk ◽

Allan Downie

Keyword(s):

Single Phase ◽

Low Voltage ◽

Harmonic Distortion ◽

Distribution Networks ◽

Harmonic Load ◽

Medium Voltage ◽

Voltage Distortion ◽

Pv Inverter ◽

Distributed Measurement ◽

Selection Of

This paper focuses on studying the phenomenon of harmonic distortion propagation through distribution networks. This phenomenon is governed by a combination of factors involving the nature of harmonic loads and their dynamic interaction, the influence of background voltage distortion, and harmonic impedance values. The objective of the proposed research includes evaluation of the network response at different nodes to harmonic current injections via utilizing a time-synchronized distributed measurement system. The study is performed in a fully controlled and flexible test network with three medium voltage/low voltage (MV/LV) distribution substations and several managed LV harmonic sources, namely PV inverter, single-phase EV charger and emulated harmonic load with reference current injections. A selection of the results is analyzed and interpretation of the observed phenomena is given with implications that synchronized harmonic measurements can be considered as potential powerful instruments for analyzing power quality disturbances.

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