Virtual inertia control system of independent wind storage DC micro-grid

Abstract

The invention discloses a virtual inertia control system of an independent wind storage DC micro-grid. By the control system, potential energy of rotating equipment in a wind-power DC micro-grid is fully developed; DC bus voltage is associated with rotating speed adjustment of a permanent-magnet direct-driven wind turbine generator set; and electromagnetic power of a PMSG is quickly adjusted in a system disturbance by employing the rapidity of power electronic control, so that the rotating speed of a rotor of a permanent magnet synchronous motor changes, the energy in the rotor is released or absorbed and the inertia of the independent DC micro-grid is improved. By a virtual inertia control strategy disclosed by the invention, the voltage stability of the DC micro-grid can be improved, charge-discharge current of a storage battery can also be improved, the storage battery is protected and the service lifetime of the storage battery is prolonged.

Description

technical field [0001] The invention relates to a control system, in particular to a virtual inertia control system of an independent wind-storage DC microgrid. Background technique [0002] Under the dual pressure of energy demand and environmental protection, the international community has turned more attention to the technical field of distributed power generation that can not only improve the efficiency of traditional energy utilization but also make full use of various renewable energy sources. Micro-grid technology is an effective way to exert the efficiency of distributed power, which has important economic significance and social value. Traditional research on microgrids is mainly focused on AC microgrids, but with the emergence of a large number of DC microsources and the increase in demand for DC power on the load side, DC microgrids have gradually gained people's attention. Compared with the AC microgrid, the DC microgrid has higher efficiency, stronger transmis...

AI Technical Summary

Problems solved by technology

The lack of system inertia will cause the following problems: (1) When the system is disturbed, the bus voltage will deviate from the rated value instantaneously, causing the protection to operate, causing load shedding, power off-grid and other faults; (2) system load mutation or load When the motor starts suddenly, the charging and discharging current of the battery increases instantaneously and even exceeds the maximum current of the battery, causing damage to the battery and further affecting the stability of the system; (3) When the load fluctuates in a small range, the battery is charged and discharged in a short time, increasing the Many unnecessary charge and discharge times greatly reduce the service life of the battery

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