A Reliability Assessment Method for Microgrids Dependent on Operating Conditions

Abstract

The present invention proposes an operating condition dependency-based microgrid reliability evaluation method and belongs to the microgrid technical field. The evaluation method includes the following steps that: (1) original data are processed, so that scenes represented by at least one data variable are obtained, and the output values of a micro power source under each scene are determined; (2) the power difference value of the microgrid is calculated, and the charging and discharging power of an energy storage device is determined; (3) voltage and current distribution in the microgrid under each scene is calculated; (4) based on the voltage and current distribution, the probability of occurrence of the dependency of various kinds of fault conditions is calculated according to a power electronic device fault model, a power conversion circuit topology structure and a protection device action probability model in the microgrid; and various types of faults are listed, influence on a reliability index caused by the faults is evaluated according to a load switching strategy enabling optimal economical efficiency; and (6) statistical analysis is performed on results obtained in step (5), so that the annual reliability index of the microgrid can be obtained. With the method of the present invention adopted, the reliability of the operation of the microgrid can be evaluated more accurately.

Description

technical field [0001] The invention belongs to the technical field of micro-grids, and relates to a method for evaluating the reliability of micro-grids. Background technique [0002] As a new hotspot in the field of power system research, microgrid can bring many benefits to the power system. Due to the limitations of the manufacturing process and technical level of the micro-power supply at the present stage, the economic advantages of the micro-grid cannot be reflected. The advantages of improving the reliability of power supply are the main driving force to promote the research of the micro-grid. The high failure rate of power electronic devices and imperfect protection schemes in the microgrid will have a negative impact on the reliability of the system's power supply. At present, most of the assessment methods involving the impact of component failures in the grid on the reliability of microgrids use the sequential Monte Carlo method based on the Markov chain, the wo...

AI Technical Summary

Problems solved by technology

In addition, the variability of operating conditions has brought new challenges to the relay protection scheme of the microgrid. The failure probability of conventional protection methods is very high; The circuit becomes a non-negligible influencing factor in the reliability evaluation

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