Unlock instant, AI-driven research and patent intelligence for your innovation.

Transient stability analysis method for power system containing VSG-IIDG based on energy function

A transient stability analysis, power system technology, applied in electrical components, circuit devices, AC network circuits, etc., can solve problems such as sudden changes in the total energy function of the system, sudden changes in magnetic potential energy, and non-compliance with Lyapunov conditions.

Active Publication Date: 2019-04-19
NANJING UNIV OF SCI & TECH +1
View PDF2 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide an energy function-based transient stability analysis method for a VSG-IIDG power system to solve the sudden change of the magnetic potential energy of the system due to the change of the virtual power angle characteristics when the inverter current reaches saturation under the VSG strategy , which in turn leads to a sudden change in the total energy function of the system, which does not meet the Lyapunov condition

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
  • Transient stability analysis method for power system containing VSG-IIDG based on energy function
  • Transient stability analysis method for power system containing VSG-IIDG based on energy function
  • Transient stability analysis method for power system containing VSG-IIDG based on energy function

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0048] An energy function-based transient stability analysis method for power systems containing VSG-IIDG, comprising the following steps:

[0049] The first step is to model the virtual power angle characteristics of the inverter, and obtain the power angle characteristic equations of the inverter under the conditions of unsaturated current and saturated current, and the expressions are as follows:

[0050]

[0051] In the formula, V is the inverter output voltage when the inverter current is not saturated, U is the voltage on the infinite grid side, X ∑ is the reactance between the inverter and the infinite grid, I max After the current is saturated, the inverter fades into the maximum output current of the Norton equivalent current source.

[0052] At the boundary point between current saturation and unsaturation, the system will have a corresponding virtual power angle δ′ m , when the virtual power angle of the inverter is less than δ′ m When , the inverter works alo...

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 transient stability analysis method for a power system containing VSG-IIDG based on an energy function. The transient stability analysis method comprises the steps of: fitting virtual power angle characteristic curves of an inverter in different operating states, so that output electromagnetic power and virtual power angles of the inverter are represented by means of a unified model on the premise of not changing the virtual power angle characteristics, and the inverter performs power output according to the fitted virtual power angle characteristic curve; and finally, determining whether the system is stable correctly since the system energy function constructed according to electromagnetic power after fitting calculation strictly conforms to the Lyapunov condition. The constructed system energy function has negative definiteness and can determine whether the system is stable correctly, and is of great significance to analyze the transient stability of the system containing the VSG strategy inverter.

Description

technical field [0001] The invention relates to an inverter transient stability analysis technology, in particular to an energy function-containing VSG-IIDG power system transient stability analysis method. Background technique [0002] Distributed power generation (DG) is mainly integrated into the large power grid through power electronic converters such as inverters, while traditional inverters cannot provide the necessary voltage support, frequency support and damping required by the system for the grid, while virtual The introduction of synchronous generator (VSG) technology has solved the above problems well, but this type of inverter usually has a current limiting control link. Under large disturbances, when the inverter current will reach saturation, the inverter The inverter will fade into a current source, which will not only make the transient process of the inverter more complicated, but also change the virtual power angle characteristics of the inverter, which w...

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
IPC IPC(8): H02J3/00H02J3/38
CPCH02J3/00H02J3/38H02J2203/20
Inventor 焦永辉卜京龚睿殷明慧周前张宁宇汪成根刘建坤
Owner NANJING UNIV OF SCI & TECH