Partial Power Conversion and High Voltage Ride-Through Scheme for a PV-Battery Based Multiport Multi-Bus Power Router

ABSTRACT:

 With the development of renewable energy technology, distributed power supply mode with multi energy and multi-directional power flow including utility grid, renewable energy and energy storage unit has gradually become a research hotspot. An AC/DC hybrid multi-port power routing (MPPR) system which based on partial power conversion (PPC) of dual DC buses is proposed in this paper. The photovoltaic (PV) port, the battery port and two DC voltage buses form a power router. PV maximum power point tracking (MPPT) and high-voltage ride through (HVRT) of the grid-tied inverter are implemented by the same auxiliary port voltage modulation. The PPC based PV conversion features that only the power determined by voltage difference between PV panel and the series connected DC bus is dealt with, which significantly reduces the loss compared to the full power conversion (FPC) for PV. The detailed control schemes of all converters and energy transmit are given. The simulation and experimental results verify the effectiveness of the proposed scheme.

 KEYWORDS:

1.      Partial power conversion

2.      Multi-port power routing

3.      High voltage ride-through

4.      PV-battery

5.      Grid-connected system

SOFTWARE: MATLAB/SIMULINK

 BLOCK DIAGRAM:

 

 

Figure 1. The MPPR Topology Of PV-Battery Grid-Connected System.

 

EXPECTED SIMULATION RESULTS:

 

Figure 2. Simulation Result Of Case I.

Figure 3. The Steady-State Waveform In 0-1s.

Figure 4. Simulation Result Of Case II.

CONCLUSION:

This article proposes a PV-battery based multi-port power routing. Compared with the traditional PV-battery grid-connected system, the proposed MPPR in this paper has two main characteristics implemented by one auxiliary port simultaneously: first is the partial power conversion of the DC/DC stage, which significantly improves the power transfer efficiency. Secondary, MPPR realizes HVRT on the premise of maintaining normal PV output, and auxiliary port is adaptive to the grid-side voltage swell by adjusting its voltage so as to improve the voltage level of three phase converter DC bus. The system can flexibly realize the power exchange between three ports, two DC buses and the grid.

REFERENCES:

 

[1] A. Sangwongwanich, Y. Yang, and F. Blaabjerg, ``High-performance con- stant power generation in grid-connected PV systems,'' IEEE Trans. Power Electron., vol. 31, no. 3, pp. 1822_1825, Mar. 2016.

[2] C. Zhong, Y. Zhou, X. Zhang, and G. Yan, ``Flexible power-point-tracking- based frequency regulation strategy for PV system,'' IET Renew. Power Gener., vol. 14, no. 10, pp. 1797_1807, Jul. 2020.

[3] H. Fathabadi, ``Improving the power ef_ciency of a PV power generation system using a proposed electrochemical heat engine embedded in the system,'' IEEE Trans. Power Electron., vol. 34, no. 9, pp. 8626_8633, Sep. 2019.

[4] Y. Liu, S. You, and Y. Liu, ``Study of wind and PV frequency control in U.S. power grids_EI and TI case studies,'' IEEE Power Energy Technol. Syst. J., vol. 4, no. 3, pp. 65_73, Sep. 2017.

[5] H. Sugihara, K. Yokoyama, O. Saeki, K. Tsuji, and T. Funaki, ``Economic and ef_cient voltage management using customer-owned energy storage systems in a distribution network with high penetration of photovoltaic systems,'' IEEE Trans. Power Syst., vol. 28, no. 1, pp. 102_111, Feb. 2013.