Grid-connected current control method suitable for MMC half-bridge series structure microgrid

A series structure, current control technology, applied in the direction of circuit devices, AC network circuits, single-network parallel feeding arrangements, etc., can solve the problems of inconspicuous control effect, poor dynamic performance, and difficult determination of control parameters, etc., to achieve global stability performance, solve the difficulty of parameter determination, and improve the stability

Pending Publication Date: 2020-08-07
LANZHOU UNIVERSITY OF TECHNOLOGY
View PDF0 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

If traditional current control methods such as hysteresis control, proportional integral control, and proportional resonance control are used, problems such as difficulty in determining control parameters and poor dynamic performance will result, and the control effect will not be obvious.

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
  • Grid-connected current control method suitable for MMC half-bridge series structure microgrid
  • Grid-connected current control method suitable for MMC half-bridge series structure microgrid
  • Grid-connected current control method suitable for MMC half-bridge series structure microgrid

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0039]The current control method involved in the present invention will be described in detail below with reference to the drawings and specific embodiments. In this embodiment, the technical solution of the present invention is given in detail, but the scope of protection of the present invention is not limited to the following embodiments.

[0040] The grid-connected topology of the MMC half-bridge series microgrid (MMC-MG) is as follows: figure 1 As shown, each phase has 2N generation modules (Generation Module, GM); in order to suppress the circulation, the upper and lower bridge arms of each phase are connected in series with inductor L; GM is composed of wind (photovoltaic) micro-source, AC / DC controllable rectifier circuit (DC / DC DC conversion circuit), energy storage device ES, half-bridge converter (Half-bridgeConverter, HC).

[0041] In normal operation, GM has two states of input and cut-off. When GM is in the input state (in HC, S1=1 (on), S2=0 (off)), its output ...

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 discloses a grid-connected current control method suitable for an MMC half-bridge series structure microgrid. The MMC-MG grid-connected system comprises 6N power generation modules GM, an MMC three-phase inversion link, a power grid and an AC load. The current control method comprises the following steps of establishing a state equation of the system by an MMC-MG equivalent circuit model, according to the established state equation, obtaining an Euler-Lagrange (EL) model, and selecting an error energy function, setting a damping term, and realizing grid-connected current controlof the MMC half-bridge series structure microgrid (MMC-MG) according to the obtained passive control law in combination with a classical proportional integral controller. The method has the advantagesof simple structure, good dynamic performance, low output current harmonic content, good stability and the like.

Description

technical field [0001] The invention relates to the technical field of micro-grid control, in particular to a grid-connected current control method of a MMC half-bridge series structure micro-grid (Modular Multilevel Converter Micro Grid, MMC-MG). Background technique [0002] In recent years, with the rapid development of microgrid technology, traditional H-bridge inverters no longer meet the needs of flexible control of power generation units and low harmonic pollution due to device withstand voltage performance and control performance. Modular multilevel converters (ModularMultilevel Converter, MMC) has been promoted and applied in the new microgrid system structure. MMC has the characteristics of multi-level output voltage, easy expansion of sub-modules, and low switching frequency. Combining the above advantages, micro-sources such as wind power, photovoltaics, and micro-gas turbines are connected to the DC side of MMC neutron modules through converters to construct a s...

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): H02J3/38
CPCH02J3/38H02J2203/20
Inventor 王兴贵王海亮薛晟李晓英郭群杨维满郭永吉
Owner LANZHOU UNIVERSITY OF TECHNOLOGY
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