Non-isolated photovoltaic grid-connected inverter and control method thereof

A control method and inverter technology, which are applied in photovoltaic power generation, control/regulation systems, irreversible DC power input conversion to AC power output, etc. The cost increases and the loss of the grid-connected inverter increases, so as to reduce the harmonics of the grid-connected current, improve the quality of the grid-connected waveform, and reduce the reverse recovery loss.

CN102684522AInactive Publication Date: 2012-09-19SHANGHAI CONVERTERGY ENERGY TECH
6 Cites 10 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Publication Date
2012-09-19
Estimated Expiration
Not applicable · inactive patent

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The invention discloses a non-isolated photovoltaic grid-connected inverter and a control method thereof and belongs to the technical field of power electronics converters. The inverter comprises a power supply circuit (10), a high-frequency chopper circuit (20) and a low frequency inverter circuit (30), wherein the power supply circuit (10) is formed by a photovoltaic array and an input filter capacitor, the high-frequency chopper circuit (20) is formed by a first to a second power switch tube, a first diode and a first to a second filter inductor, the low frequency inverter circuit comprises a third, a fourth, a fifth and a sixth power switch tube, the first power switch tube and the second power switch tube are high frequency switches, and the third power switch tube, the fourth power switch tube, the fifth power switch tube and the sixth power switch tube are low frequency switches. The non-isolated photovoltaic grid-connected inverter and the control method thereof have the advantages that leakage current of the grid-connected inverter can be eliminated, grid-connected current waveforms qualities are improved, simultaneously the efficiency is high, the controlling is simple, the reliability is high and the like.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention relates to the technical field of new energy power generation, in particular to a power converter and a corresponding control method. Background technique

[0002] Photovoltaic grid-connected power generation is the most important way of solar power generation application. According to statistics, more than 90% of the installed capacity of photovoltaic power generation equipment in the world is for grid-connected applications.

[0003] Photovoltaic grid-connected inverter is a bridge connecting solar photovoltaic power generation equipment to the grid, and is one of the most critical devices in photovoltaic grid-connected power generation systems. Classified according to the isolation method, photovoltaic grid-connected inverters can be divided into power frequency transformer isolation type, high frequency transformer isolation type and non-isolation type. Compared with the other two photovoltaic grid-connected inverters, the non-isolat...

Examples

Embodiment Construction

[0024] In order to make the technical means, creative features, goals and effects achieved by the present invention easy to understand, the present invention will be further described below in conjunction with specific illustrations.

[0025] The main circuit of the non-isolated photovoltaic grid-connected inverter provided by the present invention is as attached figure 1 As shown, it includes a power supply circuit (10), a high-frequency chopper circuit (20) and a low-frequency inverter circuit (30).

[0026] Wherein the power supply circuit (10) consists of a photovoltaic array (PV) and an input filter capacitor (C in ) form, the high-frequency chopping circuit (20) is made up of the first power switch tube (S 1 ), the second power switch tube (S 2 ), the first diode (D 1 ), the first filter inductor (L 1 ) and the second filter inductor (L 2 ) constitutes, the low-frequency inverter circuit (30) is made up of the 3rd, the 4th, the 5th and the 6th power switch tube (S ...