Power compensation method for unbalanced direct power control of voltage controlled grid-connected inverter

A power compensation and power control technology, applied in the direction of reducing the asymmetry of the polyphase network, adjusting/eliminating/compensating the reactive power, eliminating/reducing the asymmetry of the polyphase network, etc. It can solve the problem of limiting the system control bandwidth and affecting the system dynamics and stable response

Inactive Publication Date: 2010-09-29
ZHEJIANG UNIV
View PDF4 Cites 47 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Although the positive and negative sequence currents of the VSC are expressed as direct currents in the positive and negative synchronous speed coordinate systems respectively, two PIs can be used to track without static error, but

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
  • Power compensation method for unbalanced direct power control of voltage controlled grid-connected inverter
  • Power compensation method for unbalanced direct power control of voltage controlled grid-connected inverter
  • Power compensation method for unbalanced direct power control of voltage controlled grid-connected inverter

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0028] The present invention will be further described below in conjunction with the accompanying drawings, and the purpose and effect of the present invention will become more obvious.

[0029] figure 2 The invention proposes a power compensation method for direct power control of a voltage-type grid-connected inverter (GC-VSI) under the condition of grid voltage asymmetry. Taking a 2kW VSC as an example, the structure of the VSC main circuit is as follows: image 3 As shown, a three-phase fully-controlled bridge 1 composed of grid 14 , line inductance 2 , line resistance 12 , IGBT switch tube 19 and its driver (or IPM module), DC bus capacitor 20 and DC link equivalent power supply 4 is included. The control loop includes: a control chip, a three-phase voltage Hall sensor 5 , a three-phase current Hall sensor 6 , and a single-phase voltage Hall sensor 3 . The control chip usually adopts DSP (such as TI's TMS320LF2812, etc.), and the control process implemented in the DSP ...

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 power compensation method for unbalanced direct power control of a voltage controlled grid-connected inverter, which is suitable for direct power control (the conventional direct power control) without synchronous speed rotational coordinate transformation. The method comprises the following steps of extracting negative sequence voltage signals and positive sequence current signals by collecting voltage and current signals of a three-phase electric network; and computing compensation items of active and reactive power according to selected control targets. In the method of the invention, the compensation items of active and reactive power are injected in the power reference signals of the conventional direct power control according to required control targets so as to respectively eliminate negative sequence current, double frequency fluctuation of the active power and double frequency fluctuation of the reactive power in the electric network, caused by unbalanced voltage in the electric network, and fit different application situations. The invention has the advantages of enhancing the capabilities of control and uninterrupted operation of the voltage controlled grid-connected inverter when the electric network is in an unbalanced fault.

Description

technical field [0001] The invention relates to a voltage-type inverter PWM control technology in the field of power electronics, in particular to a power compensation method for a voltage-type grid-connected inverter to enhance direct power control under the condition of grid voltage asymmetry. Background technique [0002] With its excellent input and output characteristics, voltage-type PWM inverters are widely used in wind power generation, photovoltaic power generation and other new energy generation, as well as high-voltage direct current transmission and other fields. Vector control (VC) and direct power control (DPC) are the main control strategies of voltage source PWM inverter. The research on the direct power control of the voltage source PWM inverter under normal power grid conditions has been relatively complete. However, since the areas rich in wind energy and solar energy are mostly remote and far away from the core large power grid, the power grid is relativ...

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): H02J3/18H02J3/38H02J3/26
CPCY02E40/32Y02E40/50Y02E40/30
Inventor 尚磊孙丹
Owner ZHEJIANG UNIV
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

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap