New energy storage system for centralized access of flexible traction transformer and control method

Abstract

The invention discloses a new energy storage system with a centralized access flexible traction transformer and a control method. The new energy storage system comprises the flexible traction transformer, an isolated DC / DC converter, a DC bus, a new energy power generation system and an energy storage system. The flexible traction transformer is connected with the isolated DC / DC converter; the isolated DC / DC converter is connected with the new energy power generation system and the energy storage system through a DC bus. The new energy power generation system is connected with the direct current bus and is used for accessing power to the direct current link of the flexible traction transformer through the isolated DC / DC converter; the energy storage system is used for effectively stabilizing the intermittency and fluctuation of new energy power generation; the number of the connected cascade modules can be reasonably and flexibly designed according to the capacity of the connected new energy, the new energy is effectively consumed while the optimal cost and the maximum benefit are guaranteed, and the utilization rate of the new energy and regenerative braking energy is improved under the condition that coordination control is relatively simple; traction net transformation is not involved, and engineering implementation is easy.

Description

technical field [0001] The invention relates to the field of new energy storage systems, in particular to a new energy storage system and a control method that is centrally connected to a flexible traction transformer. Background technique [0002] There have been a large number of research results and application cases of new energy power generation in the field of power systems, and the use of new energy power generation for electrified railway traction performance is still a relatively new research direction. [0003] At present, domestic and foreign researches on the access of new energy to electrified railways mainly focus on the power supply of low-voltage systems such as station power and signals and communications, and there are few studies on access to traction power supply systems. The connection of new energy power generation to the traction power supply system will involve complex connection structures and control methods. The prior art provides a control system...

AI Technical Summary

Problems solved by technology

The connection of new energy power generation to the traction power supply system will involve complex connection structures and control methods

The prior art provides a control system involving in-phase traction power supply and off-site power generation grid connection, but this method does not consider the coexistence of multiple new energy sources, nor does it involve how to connect multiple new energy sources to the traction power supply system; There is also a distributed power generation system and control method involving access to traction substations. This method is to install new energy converging power cables in the corridors along the railway, and then connect to the traction bus of traction substations. Large cable consumption, increased number of access points lead to complex power flow distribution and other problems, and the fluctuation and intermittency of new energy will directly affect the stability of the traction network through the traction bus, and aggravate the resonance of the vehicle network; it also involves a distributed power supply system for the AT traction network. However, there are still defects that new energy fluctuations affect the traction network

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