Ultrahigh voltage modular multilevel flexible DC transmission neutral point grounding method

A modular multi-level, flexible DC power transmission technology, applied in emergency protection circuit devices, electrical components, circuit devices, etc. for limiting overcurrent/overvoltage, can solve problems such as inability to effectively uniform fault currents, and achieve occupancy Small ground area, high economy, and the effect of suppressing fault current

Inactive Publication Date: 2018-10-09
GLOBAL ENERGY INTERCONNECTION RES INST CO LTD +4
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0009] To sum up, the existing transformer wiring and grounding methods cannot effectively and consistently fault current

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Ultrahigh voltage modular multilevel flexible DC transmission neutral point grounding method
  • Ultrahigh voltage modular multilevel flexible DC transmission neutral point grounding method
  • Ultrahigh voltage modular multilevel flexible DC transmission neutral point grounding method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0053] The detailed content and specific embodiments of the present invention will be further described below in conjunction with the accompanying drawings.

[0054] See Figure 1 to Figure 17 As shown, the UHV modular multi-level flexible DC transmission midpoint grounding method of the present invention proposes a Ynyrd neutral point high resistance grounding method suitable for UHV flexible DC transmission based on Yny wiring transformers. Combined with UHV flexible DC transmission, and considering the magnitude of zero-sequence current and DC bias current, the parameter design of neutral grounding resistance is carried out. Mainly for the unipolar symmetrical solution, and the AC system is a directly grounded system, so the grid side of the transformer must be connected to the Yn connection method. In order to prevent the zero sequence current of the DC system from entering the AC side through the connecting transformer during a fault, it is required to connect the valve side ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention relates to an ultrahigh voltage modular multilevel flexible DC transmission neutral point grounding method, which belongs to the field of ultrahigh voltage flexible DC transmission. Themethod comprises the steps that: a balancing winding is additionally arranged on a transformer with Yny wiring; a capacity and a voltage class of the balancing winding are calculated; and neutral point grounding resistance parameters are designed. A connecting transformer adopts a Ynyrd neutral point high-resistance grounding mode, and in the method, the defect of large third harmonic loss when apower system at an early stage uses the Yny wiring transformer can be solved through additionally arranging a third wiring in delta connection as the balancing winding. The ultrahigh voltage modular multilevel flexible DC transmission neutral point grounding method has the advantages that the occupied area is small, a grounding transformer can be saved, the economic performance is higher, and themanufacturing difficulty is reduced.

Description

Technical field [0001] The invention relates to the field of UHV flexible direct current transmission, in particular to a midpoint grounding method of UHV modular multilevel flexible direct current transmission. Background technique [0002] UHV DC transmission technology refers to the transmission technology using higher voltage levels above 500kv and 750kv AC and ±500kv DC, including two parts: AC UHV transmission technology and DC UHV transmission technology. The study of UHV transmission technology abroad has a history of nearly 40 years. Regardless of whether it is UHV DC transmission or UHV AC transmission, it is to better improve the transmission capacity, realize high-power medium and long-distance transmission, and realize the interconnection of long-distance power systems to build a joint power system. [0003] my country has a vast territory, and the distribution of energy reserves and power loads is extremely uneven. In the construction of power grids, energy distribu...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): H02H9/02
CPCH02H9/02
Inventor 涂莉阳岳希杨杰钱康杨勇韩旭杉马彦宏辛业春宋祯子
Owner GLOBAL ENERGY INTERCONNECTION RES INST CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products