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

A high-gain low-stress photovoltaic multi-level inverter and control method

A multi-level inverter, low-stress technology, applied in photovoltaic power generation, electrical components, conversion of AC power input to DC power output, etc., can solve the problem of maximum power point voltage reduction, DC capacitor voltage equalization, and photovoltaic power generation units The output voltage cannot meet the grid-connected requirements, etc., so as to reduce the control complexity and improve the output level

Active Publication Date: 2022-07-26
ZHENGZHOU UNIV
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, traditional multi-level inverters use a large number of diodes and capacitors, and the DC capacitors of flying-capacitor and diode-clamped inverters still have voltage equalization problems.
In addition, the output voltage of photovoltaic power generation units usually cannot meet the grid-connected requirements. Factors such as sunlight, temperature, and shadow may cause the maximum power point voltage to decrease, while traditional multi-level inverters do not have a boost function.

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
  • A high-gain low-stress photovoltaic multi-level inverter and control method
  • A high-gain low-stress photovoltaic multi-level inverter and control method
  • A high-gain low-stress photovoltaic multi-level inverter and control method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0053] like figure 1 As shown, a high-gain low-stress photovoltaic multi-level inverter includes a boost unit, an I-shaped switch structure, and an independent capacitor C 3 and two half-bridge structures; the inverter in this embodiment consists of a boost unit and an independent capacitor C 3 It is formed by connecting an I-shaped switch structure, and uses two half-bridge structures instead of H-bridges to switch the polarity of the output level.

[0054] The boosting unit includes a photovoltaic DC power supply E, an electrolytic capacitor C 1 , Electrolytic capacitor C 2 , switch tube S 2 , switch tube S 3 , switch tube S 4 , switch tube S 5 , switch tube S 6 and switch S without reverse diode 1 ; the switch tube S 1 The input end and the switch tube S 2 The input end of the photovoltaic DC power supply E is connected to the positive pole; the switch tube S 1 The output terminal with electrolytic capacitor C 1 anode, switch tube S 5 connected to the input end...

Embodiment 2

[0065] like figure 2 As shown, this embodiment provides an expandable high-gain low-stress photovoltaic multi-level inverter, including the high-gain low-stress photovoltaic multi-level inverter described in Embodiment 1 and an expandable module;

[0066]The expandable module includes a switch tube S 16 , switch tube S 17 , switch tube S 18 , switch tube S 19 , switch tube S 20 and electrolytic capacitor C 4 ; the switch tube S 16 The input end and the switch tube S 19 input terminal, electrolytic capacitor C 4 The anode is connected; the switch tube S 16 The output end and the switch tube S 18 connected to the input end; the switch tube S 17 The input end and the switch tube S 18 connected to the output end; the switch tube S 17 The output end and the switch tube S 20 , the electrolytic capacitor C 4 connected to the cathode.

[0067] The boost unit charges all the expandable modules at the same time, and each module can be discharged in series with the boost ...

Embodiment 3

[0069] This embodiment provides a control method for a high-gain and low-stress photovoltaic multi-level inverter:

[0070] A drive signal is generated, and the high-gain low-stress photovoltaic multi-level inverter described in Embodiment 1 is controlled by the drive signal to work in 17 working states and output 17 levels, and the high-gain low-stress photovoltaic multi-level inverter The level inverter outputs 4 times the voltage gain.

[0071] Specifically, as shown in Fig. 3(a)-3(d), the modulation principle is shown in Fig. 3(a)-3(d), the carrier stacking pulse width modulation technology is used, and 16 triangular carriers with the same amplitude and the same frequency are stacked in sequence, and a sine modulated wave is used. After comparison, the obtained 16-channel original pulse waveforms are logically combined to obtain the gate pulse drive signal used to drive the switch tube on and off. The inverter has a large number of output levels, and the principle of the ...

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 present invention provides a high gain and low stress photovoltaic multilevel inverter. The inverter uses 1 photovoltaic DC power supply, 3 capacitors and 15 switching devices to achieve 4 times the voltage gain and 17-level AC voltage output. The proposed inverter can generate more levels with fewer switching devices, which effectively reduces the output harmonic content of the inverter; the inverter process can be realized without the back-end H-bridge, which effectively reduces the voltage of the switching devices Stress; bidirectional current loop at each output level enables inductive load capability. In addition, the capacitor voltage ripple of the proposed inverter is small, and the advantages of capacitor voltage self-balancing simplify the complexity of the controller.

Description

technical field [0001] The invention relates to a high-gain and low-stress photovoltaic multilevel inverter and a control method, belonging to the field of electric energy conversion and new energy power generation, and in particular to the field of photovoltaic power generation. Background technique [0002] Renewable energy is widely used, and the demand for renewable energy in countries around the world is also increasing day by day. Renewable energy power generation, such as photovoltaic power generation, has become an increasingly important power generation method. The DC power generated by the photovoltaic module needs to supply power to the load or connect to the AC grid through the inverter, so the high-performance inverter is very important in the photovoltaic power generation system. [0003] Compared with two-level inverters, multi-level inverters have less electromagnetic interference and can output higher-quality sinusoidal waveforms while bearing higher voltag...

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 Patents(China)
IPC IPC(8): H02M7/5387H02M1/088H02M1/14H02M1/32
CPCH02M7/53871H02M1/088H02M1/14H02M1/32Y02E10/56
Inventor 王要强张亨泰赖锦木王金凤王克文梁军
Owner ZHENGZHOU 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