SEAMLESS SWITCHING METHOD AND SYSTEM FOR MICRO-GRID SYSTEM

• Main Authors: SU, WEIFENG, LIU, ZHIQIANG, ZHANG, DONGSHENG, WEI, SANMIN, GOU, RUIFENG
• Format: Patent
• Language: Chinese; English; French
• Published: 02.07.2015
• Subjects: CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTINGELECTRIC POWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION; SYSTEMS FOR STORING ELECTRIC ENERGY

A seamless switching method and system for a micro-grid system. The method comprises: a first voltage collection module collecting values of various phase voltages at a grid side connected thereto; a PCS determining the power-loss ratio of the current voltage value of each phase voltage relative to a standard value, and counting the sum of the number of times of the power-loss ratios of various phase voltages being lower than a predetermined value; and if the PCS judges that the value of the sum is larger than a threshold value, executing V/F switching, and at the same time, triggering a PCC switch between the grid connected thereto and a micro-grid to be disconnected. By means of the manner of switching from on-grid to off-grid, the current impact is very small, and the smooth switching from on-grid to off-grid can be achieved. L'invention concerne un procédé et un système de commutation sans à-coups pour un système de micro-réseau. Le procédé comprend : un premier module de prélèvement de tension prélevant