A Novel Control Strategy of Suppressing DC Current Injection to the Grid for Single-Phase PV Inverter

He, Guoqing; Xu, Dehong; Chen, Min

doi:10.1109/tpel.2014.2317288

Cited by 64 publications

(32 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The dc current injection is mainly caused by the measurement errors from current sensors, and it may affect the normal operation of distribution transformers. To cope with this issue, an additional dc suppression loop can be introduced to control the dc current injection as discussed in [40]. Regarding the safety issue, the PV module frames should be grounded in transformerless PV systems in order prevent electric shocks and fire hazards.…”

Section: Circuit Configuration and Leakage Current Eliminationmentioning

confidence: 99%

Highly Reliable Transformerless Photovoltaic Inverters With Leakage Current and Pulsating Power Elimination

Tang

Yao

Loh

et al. 2016

IEEE Trans. Ind. Electron.

184

View full text Add to dashboard Cite

This paper presents a transformerless inverter topology, which is capable of simultaneously solving leakage current and pulsating power issues in grid-connected photovoltaic (PV) systems. Without adding any additional components to the system, the leakage current caused by the PVto-ground parasitic capacitance can be bypassed by introducing a common mode (CM) conducting path to the inverter. The resulting ground leakage current is therefore well controlled to be below the regulation limit. Furthermore, the proposed inverter can also eliminate the well-known double line frequency pulsating power that is inherent in single-phase PV systems. By properly injecting CM voltages to the output filter capacitors, the pulsating power can be decoupled from the dc-link. Therefore, it is possible to use long lifetime film capacitors instead of electrolytic capacitors to improve the reliability of the PV system. The mechanism of leakage current suppression and the closedloop control of pulsating power decoupling are discussed in the paper in details. A 500 W prototype was also built and tested in the laboratory, and both simulation and experimental results are finally presented to show the excellent performance of the proposed PV inverter.  Index Terms-Leakage current, power decoupling, singlephase system, transformerless photovoltaic inverter

show abstract

Section: Circuit Configuration and Leakage Current Eliminationmentioning

confidence: 99%

Highly Reliable Transformerless Photovoltaic Inverters With Leakage Current and Pulsating Power Elimination

Tang

Yao

Loh

et al. 2016

IEEE Trans. Ind. Electron.

184

View full text Add to dashboard Cite

show abstract

“…On the other hand, the authors in [13], [14] are discussing a measurement technique to detect the dc offset between the inverter output terminals using RC filters and voltage transformers, in which the common mode voltage problems should be effectively considered. Similarly, the authors in [15], [16] are discussing the dc current component measurement and mitigation using output low-pass filters and voltage sensors for single-phase and three-phase systems. Also in [17], the authors are using a reactor with a specific design combined with a current transformer and an LC filter to mitigate the dc component.…”

Section: Introductionmentioning

confidence: 99%

Coupled-Inductor-Based DC Current Measurement Technique for Transformerless Grid-Tied Inverters

Abdelhakim

Mattavelli

Yang

et al. 2018

IEEE Trans. Power Electron.

View full text Add to dashboard Cite

Grid-tied photovoltaic (PV) inverters must fulfill several requirements, including high efficiency and reduced cost and complexity of the overall system. Hence, transformerless operation is advantageous in order to achieve the prior requirements. Meanwhile, such operation results in several demerits, like the dc current component injection into the grid. This component should be effectively mitigated in order to avoid some impacts, like the saturation of the transformers in the distribution network. On the other hand, limiting this component up to few milliamperes is seen to be a challenging issue due to the various measurement errors.Accordingly, different blocking and measurement techniques have been proposed and studied to overcome this issue, where some demerits are seen behind each technique like the implementation complexity, the common mode voltage problems, and the high filter requirements. Moreover, none of them measures the dc component directly, but predicts its value using different approaches.Hence, this letter proposes a new technique to measure this dc current component with high accuracy using a coupled-inductor combined with a small range hall effect current sensor in order to achieve the lowest possible cost with the highest possible accuracy. The proposed technique is introduced, analyzed, and tested experimentally to verify its principle of operation. Also experimental measurement of the dc current component using a 5 kVA transformerless grid-tied voltage source inverter (VSI) is introduced with and without the proposed technique in order to validate its operation.

show abstract

“…Current harmonics may come from nonlinear load operations produced by power electronic devices and applications which are injected into the supply network through point of common coupling (PCC). In smart grid systems, these problems may arise with involvement of multiple energy sources and systems which include PV grid connected system [1][2][3]. To mitigate the current harmonics, shunt active power filter (SAPF) is used rather than series APF which mitigates voltage harmonics.…”

Section: Introductionmentioning

confidence: 99%

“…To mitigate the current harmonics, shunt active power filter (SAPF) is used rather than series APF which mitigates voltage harmonics. Current harmonics are more crucial rather than voltage harmonics because in most situations, the voltage harmonics is resulted by voltage drop across the source impedance due to current harmonics inside the power system [1][2][3][4].…”

Section: Introductionmentioning

confidence: 99%

“…A good APF can successfully perform with Total harmonic Distortion (THD) of below than 5%, which obeys IEEE Standard 519-2014 (IEEE Recommended Practices and Requirements for Harmonic Control in Electric Power Systems) [6]. Apart from that, the speed of convergence of not more than 60 ms or 3 cycles of 50 Hz is required to be acceptable in many practical applications [3]. The harmonics extraction algorithms can be categorized to frequency domain, time domain and artificial intelligence techniques.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Improved ADALINE Harmonics Extraction Algorithm for Boosting Performance of Photovoltaic Shunt Active Power Filter under Dynamic Operations

Zainuri¹,

Radzi²,

Soh³

et al. 2016

Journal of Electrical Engineering and Technology

View full text Add to dashboard Cite

-This paper presents improved harmonics extraction based on Adaptive Linear Neuron (ADALINE) algorithm for single phase photovoltaic (PV) shunt active power filter (SAPF). The proposed algorithm, named later as Improved ADALINE, contributes to better performance by removing cosine factor and sum of element that are considered as unnecessary features inside the existing algorithm, known as Modified Widrow-Hoff (W-H) ADALINE. A new updating technique, named as Fundamental Active Current, is introduced to replace the role of the weight factor inside the previous updating technique. For evaluation and comparison purposes, both proposed and existing algorithms have been developed. The PV SAPF with both algorithms was simulated in MATLABSimulink respectively, with and without operation or connection of PV. For hardware implementation, laboratory prototype has been developed and the proposed algorithm was programmed in TMS320F28335 DSP board. Steady state operation and three critical dynamic operations, which involve change of nonlinear loads, off-on operation between PV and SAPF, and change of irradiances, were carried out for performance evaluation. From the results and analysis, the Improved ADALINE algorithm shows the best performances with low total harmonic distortion, fast response time and high source power reduction. It performs well in both steady state and dynamic operations as compared to the Modified W-H ADALINE algorithm.

show abstract

A Novel Control Strategy of Suppressing DC Current Injection to the Grid for Single-Phase PV Inverter

Cited by 64 publications

References 26 publications

Highly Reliable Transformerless Photovoltaic Inverters With Leakage Current and Pulsating Power Elimination

Highly Reliable Transformerless Photovoltaic Inverters With Leakage Current and Pulsating Power Elimination

Coupled-Inductor-Based DC Current Measurement Technique for Transformerless Grid-Tied Inverters

Improved ADALINE Harmonics Extraction Algorithm for Boosting Performance of Photovoltaic Shunt Active Power Filter under Dynamic Operations

Contact Info

Product

Resources

About