Characteristics Behavior of Shunt DC Electric Spring For Mitigating DC Microgrid Issues

 ABSTRACT:

There is a huge pervasive consideration of integrating renewable energy sources (RES) to DC power system. Most of the modern loads are DC. Photovoltaic (PV) integrated DC microgrids feature remarkable advantages such as providing DC which can be directly utilized in DC grids that eliminates major step of ACDC conversion. However, intermittency of RES and presence of some non- idealistic like voltage fluctuation, droop effect, faults and harmonics causes instability problems in DC microgrid. This leads to voltage weakening, potential blackout and damage to equipment. To deal with inconsistency and improbability of RES new emerging demand side management (DSM) technology has been developed called Electric Spring (ES). ES can be employed in AC or DC grid for supply-demand management. DC Electric Spring (DC-ES) is a unique method of distributed voltage control over traditional single point control by effectively handling supply. This paper comprises one of the types of DC-ES called the shunt DC-ES for voltage regulation and Fault Ride Through (FRT) support with various mode of operation on DC bus. To demonstrate the performance analysis and to alleviate DC microgrid issues, DC-ES is implemented on 48V DC system. Moreover, the detail comprehensive characteristics behavior of shunt DC-ES is presented and validated using MATLAB software.

KEYWORDS:

1.      DC-Electric Spring

2.      DC Microgrid

3.      Fault Ride Through

4.      Renewable energy sources

SOFTWARE: MATLAB/SIMULINK

CONCLUSION:

 This paper presents an effective proficiency of shunt DC-ES to fix the CL voltage and to improve Fault Ride Through (FRT) capability of DC system in case of low power DPGS like PV. The comprehensive investigation highlights the characteristics performance of shunt DC-ES for voltage variations during various DC system contingencies without energy consumption. The presented results verifies the successful performance of shunt DC-ES for mitigating different issues in DC microgrids such as voltage regulation and FRT support. It is found that the shunt configuration of DC-ES exactly follows its ideal characteristics with an excellent dynamic response.

REFERENCES:

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