A Microgrid Frequency Control Method Considering Equipment Adjustment Response Characteristics

Abstract

The invention discloses a microgrid frequency control method based on the adjusting response characteristic of devices. In the off-network operation process of a microgrid, an energy storage battery, a diesel generator, an energy management system and a measurement unit of a microgrid stable control device detect system frequency synchronously and judge whether deviation of the system frequency is out of limit or not; if deviation of the system frequency exceeds a definite value, the energy storage battery carries out charging / discharging, primary frequency modulation of the microgrid is achieved, and the system frequency is stabilized; the energy management system will monitor the discharging time of the energy storage battery synchronously; when the continuous discharging time of the energy storage battery exceeds a definite value, the energy management system outputs a power adjusting instruction to the diesel generator, the power output is adjusted, and secondary frequency modulation of the microgrid is achieved; when the continuous time of the deviation of the microgrid frequency exceeds a definite value, the microgrid stable control device will start load shedding or logic of a draught fan or the diesel generator until the microgrid frequency returns to normal. The method brings the adjusting capacity of the different devices in the microgrid into full play, and an adjusting system is simple in structure.

Description

technical field [0001] The invention relates to the field of microgrids and smart grids, in particular to a microgrid frequency control method taking into account equipment adjustment response characteristics. technical background [0002] The microgrid has a flexible operation mode, which can be operated both on-grid and off-grid. In the off-grid operation mode, due to the small power reserve capacity of the microgrid, the system frequency is easily affected by the intermittent energy with large fluctuations, which causes great difficulties for the stable operation of the microgrid. Aiming at the problem of microgrid frequency control, some methods have been proposed at home and abroad. These methods mainly stabilize the fluctuation of intermittent energy power by adjusting the output of the energy storage system. To a certain extent, these methods can eliminate the frequency deviation caused by intermittent energy power fluctuations in a short period of time, but for a mi...

AI Technical Summary

Problems solved by technology

To a certain extent, these methods can eliminate the frequency deviation caused by intermittent energy power fluctuations in a short period of time, but for a microgrid that operates off-grid for a long time, frequent adjustments to the energy storage system not only endanger its life, but also affect the capacity of the energy storage. will make high demands

Images