Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Method for carrying out model prediction control on grid-side converter of photovoltaic power generation system under unbalanced voltage

A photovoltaic power generation system, model predictive control technology, applied in the direction of photovoltaic power generation, conversion of irreversible DC power input to AC power output, single network parallel feeding arrangement, etc., can solve the problem that the model predictive control method cannot be applied and the control system is complex , large amount of calculation and other problems, to achieve the effect of avoiding rotation coordinate transformation, simple control structure, and small amount of calculation

Inactive Publication Date: 2014-02-19
HENAN NORMAL UNIV
View PDF3 Cites 26 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The existing solutions are all unbalanced control methods for vector control strategies, which cannot be applied to model predictive control methods, and require the process of rotating coordinate transformation or performing positive and negative sequence decomposition operations on control variables. The control system is relatively complex, and the amount of calculation bigger

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
  • Method for carrying out model prediction control on grid-side converter of photovoltaic power generation system under unbalanced voltage
  • Method for carrying out model prediction control on grid-side converter of photovoltaic power generation system under unbalanced voltage
  • Method for carrying out model prediction control on grid-side converter of photovoltaic power generation system under unbalanced voltage

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0013] The present invention will be further described below in conjunction with the accompanying drawings. Photovoltaic power generation system structure such as figure 1 As shown, the photovoltaic array is connected to the grid through a dc-dc converter, a DC bus, and a grid-side converter through a filter reactor and a step-up transformer. The output current of the grid-side converter directly determines the current harmonic content output to the grid.

[0014] The mathematical model of the grid-side converter in the two-phase static α-β coordinate system is

[0015] (1)

[0016] In the formula, u gα , u gβ are the α and β axis components of the grid voltage, respectively; u cα , u cβ are the α and β axis components of the output voltage of the converter, respectively; i gα , i gβ are the α and β axis components of the grid current, respectively; L g , R g Respectively, the inductance value of the reactor and the equivalent resistance of th...

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 method for carrying out model prediction control on a grid-side converter of a photovoltaic power generation system under unbalanced voltage. According to the technical scheme, the method is characterized by including the first step of carrying out analytic calculation to obtain reference current of the AC side of the converter according to voltage of a sampling grid, delayed signals and given initial power, the second step of obtaining prediction current through a prediction model under the action of voltage vectors, the third step of selecting the voltage vector, which minimizes the absolute value of the difference between the current reference value and the current prediction value, as the optimal voltage vector through a value function, and the fourth step of selecting a switch position signal corresponding to the optimal voltage vector as a switching signal for controlling a power device. Under the condition of network voltage unbalance, it is guaranteed that DC bus voltage is stable and grid-side current is sinusoidal through the control of balance of the power of the two sides of the converter. The whole process is based on a two-phase static coordinate frame, and rotational coordinate conversion is avoided. Moreover, the control method does not include the positive and negative sequence decomposition and phase locking steps, the control structure is simple, and the calculated amount is small.

Description

[0001] technical field [0002] The invention relates to a model predictive control method for a grid-side converter of a photovoltaic power generation system under unbalanced voltage, and belongs to the field of power electronic power conversion device control. Background technique [0003] Compared with the traditional vector control based on PI controller, model predictive control has the advantages of simple structure, fast dynamic response, no need to adjust controller parameters, etc. It is an advanced control method with broad application prospects. The model predictive control method is applied to the operation control of the converter in the photovoltaic power generation system, which can obtain accurate and fast current regulation effect. However, when the model predictive control method is used for control, it is assumed that the three-phase grid voltage is balanced. When the grid voltage is unbalanced, the DC bus voltage will generate double-frequency pulsation ...

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): H02J3/38H02M7/48
CPCY02E10/56
Inventor 施艳艳王萌苏明坤高金辉
Owner HENAN NORMAL UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com