CN213637544U

CN213637544U - Novel nine-level inverter

Info

Publication number: CN213637544U
Application number: CN202022982198.1U
Authority: CN
Inventors: 李文娟; 颜世博
Original assignee: Harbin University of Science and Technology
Current assignee: Harbin University of Science and Technology
Priority date: 2020-12-11
Filing date: 2020-12-11
Publication date: 2021-07-06
Anticipated expiration: 2030-12-11

Abstract

The utility model discloses a novel nine level inverter, this inverter include six IGBT switch tubes T1, T2, T3, T4, T5, T6, eight diodes D1, D2, D3, D4, D5, D6, D7, D8, four DC power supply V1, V2, V3, V4 and load resistance R. The utility model discloses can output nine different level combinations, have that power switch quantity is less, power loss is little, efficiency is higher, single switch tube switching number of times is few, the more stable advantage of work, and alternating current output voltage harmonic content is little, and the waveform distortion rate is low, can be applied to the occasion higher to the electric energy quality requirement.

Description

Novel nine-level inverter

Technical Field

The utility model belongs to power conversion equipment field, concretely relates to novel nine level inverter.

Background

With the improvement of living standard, people have more and more demands on electric energy. The use of electric energy inevitably involves an electric energy conversion technology, and an inverter can convert direct current into alternating current, which is a common device in electric energy conversion. In the inversion process, the output voltage waveform is close to a sine wave as much as possible, and the voltage distortion rate is too high, which causes various defects such as heat generation, interference, damage to electric equipment and the like. Theoretically, the more the number of levels of the inverter is, the closer the output waveform is to a sine wave, and the traditional three-level inverter is not suitable for occasions with high precision requirements.

Therefore, in order to obtain a better output waveform and to operate better using electrical equipment, a new type of nine-level inverter needs to be developed.

SUMMERY OF THE UTILITY MODEL

In order to overcome the existing problems, the utility model provides a novel nine-level inverter, which comprises six IGBT switch tubes T₁、T₂、T₃、T₄、T₅、T₆Eight diodes D₁、D₂、D₃、D₄、D₅、D₆、D₇、D₈Four DC power supplies V₁、V₂、V₃、V₄And a load resistance R.

Switch tube T₁Collector and DC power supply V₂Positive electrode and switching tube T₃Is connected with the collector of the switching tube T₁Emitter and switch tube T₂Collector electrode of (2), diode D₁Anode of (2), diode D₂Is connected with the load, and a switching tube T₂Collector and switch tube T₁Emitter, diode D₁Anode of (2), diode D₂Is connected with the load, and a switching tube T₂Emitter and power supply V₁Negative electrode of (2) and switching tube T₄Is connected with the emitting electrode of the switching tube T₃Collector of the switching tube T1 and the DC power supply V₂Is connected with the positive pole of the switching tube T₃Emitter and DC power supply T₃Is connected with the negative pole of the switching tube T₄Collector and DC power supply V₄Is connected with the positive pole of the switching tube T₄Emitter and switch tube T₂Emitter and dc power supply V₁Is connected with the negative pole of the switching tube T₅Collector and diode D₁、D₄Is connected with the negative pole of the switching tube T₅Emitter and diode D₂、D₃The positive pole of the switch tube T is connected with the positive pole of the anode₆Collector ofPolar and diode D₅、D₈Is connected with the negative pole of the switching tube T₆Emitter and diode D₆、D₇The positive electrodes of (a) and (b) are connected.

The utility model discloses four DC power supply V that use₁、V₂、V₃、V₄The voltage ratio is 1:1:2:2, and nine levels of effect are achieved through the action between the switching conversion of the switching tube and the four direct current power supplies, so that the distortion rate of the output waveform voltage is lower. The utility model provides a novel nine level dc-to-ac converter, at arbitrary moment, only two switch tubes are in the state of opening, can reduce the switch tube and open the number of times, extension switch tube life. And the nine-level inverter can achieve the nine-level effect only by using six switching tubes, so that the cost can be effectively saved.

A novel nine-level inverter topology structure diagram is shown in figure 1, the inverter has 9 working states, and equivalent circuit diagrams of the 9 working states are shown in figures 2-10.

Working state 1: let the left side of the resistor be the positive reference direction, let V₁＝V₂＝V_dc，V₃＝V₄＝2V_dcSwitch tube T₂And T₃The switch tube is in an on state, the other switch tubes are in an off state, and the voltage V on the load resistor R is at the moment_R＝V₁+V₂+V₃＝4V_dc

And 2, working state: switch tube T₃And T₅Is in an on state, the other switch tubes are in an off state, and the voltage V on the load resistor R_R＝V₂+V₃＝3V_dc

And 3, working state: switch tube T₃And T₁Is in an on state, the other switch tubes are in an off state, and the voltage V on the load resistor R_R＝V₃＝2V_dc

And the working state 4: switch tube T₂And T₆Is in an on state, the other switch tubes are in an off state, and the voltage V on the load resistor R_R＝V₁＝V_dc

And (5) working state: switch tube T₅And T₆Is in an on state, the other switch tubes are in an off state, and the voltage V on the load resistor R_R＝0

The working state 6: switch tube T₁And T₆Is in an on state, the other switch tubes are in an off state, and the voltage V on the load resistor R_R＝-V₂＝-V_dc

And the working state 7: switch tube T₂And T₄Is in an on state, the other switch tubes are in an off state, and the voltage V on the load resistor R_R＝-V₄＝-2V_dc

The working state is 8: switch tube T₄And T₅Is in an on state, the other switch tubes are in an off state, and the voltage V on the load resistor R_R＝-V₁-V₄＝-3V_dc

The working state 9: switch tube T₁And T₄Is in an on state, the other switch tubes are in an off state, and the voltage V on the load resistor R_R＝-V₁-V₂-V₄＝-4V_dc

Drawings

Fig. 1 is a topology structure diagram of a novel nine-level inverter of the present invention.

Fig. 2 is an equivalent circuit diagram of a novel nine-level inverter operating state 1 according to the present invention.

Fig. 3 is an equivalent circuit diagram of a novel nine-level inverter operating state 2 according to the present invention.

Fig. 4 is an equivalent circuit diagram of a novel nine-level inverter operating state 3 according to the present invention.

Fig. 5 is an equivalent circuit diagram of a novel nine-level inverter operating state 4 according to the present invention.

Fig. 6 is an equivalent circuit diagram of a novel nine-level inverter operating state 5 according to the present invention.

Fig. 7 is an equivalent circuit diagram of a novel nine-level inverter operating state 6 according to the present invention.

Fig. 8 is an equivalent circuit diagram of a novel nine-level inverter operating state 7 according to the present invention.

Fig. 9 is an equivalent circuit diagram of a novel nine-level inverter operating state 8 according to the present invention.

Fig. 10 is an equivalent circuit diagram of a novel nine-level inverter operating state 9 according to the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

The utility model relates to a novel nine-level inverter, including DC power supply V₁、V₂、V₃、V₄IGBT switch tube T₁、T₂、T₃、T₄、T₅、T₆Diode D₁、D₂、D₃、D₄、D₅、D₆、D₇、D₈And a load resistor R, characterized by a switching tube T₁Collector and DC power supply V₂Positive electrode and switching tube T₃Is connected with the collector of the switching tube T₁Emitter and switch tube T₂Collector electrode of (2), diode D₁Anode of (2), diode D₂Is connected with the load, and a switching tube T₂Collector and switch tube T₁Emitter, diode D₁Anode of (2), diode D₂Is connected with the load, and a switching tube T₂Emitter and power supply V₁Negative electrode of (2) and switching tube T₄Is connected with the emitting electrode of the switching tube T₃Collector and switch tube T₁Collector and dc power supply V₂Is connected with the positive pole of the switching tube T₃Emitter and DC power supply T₃Is connected with the negative pole of the switching tube T₄Collector and DC power supply V₄Is connected with the positive pole of the switching tube T₄Emitter and switch tube T₂Emitter and dc power supply V₁Is connected with the negative pole of the switching tube T₅Collector and diode D₁、D₄Is connected with the negative pole of the switching tube T₅Emitter and diode D₂、D₃The positive pole of the switch tube T is connected with the positive pole of the anode₆Collector and diode D₅、D₈Is connected with the negative pole of the switching tube T₆Emitter and diode D₆、D₇The positive electrodes of (a) and (b) are connected. Switch tube T₅And diode D₁、D₂、D₃、D₄Switch tube T6 and diode D₅、D₆、D₇、D₈Two bidirectional switches are formed. The utility model relates to a novel nine level dc-to-ac converter only two switch tubes be in the on-state at arbitrary moment, and all the other switch tubes are in the off-state.

The utility model relates to a novel nine level inverter total nine operating condition, its principle as follows:

The working state 6: switch tube T₁And T₆In the open stateIn the state that the other switch tubes are in the off state, the voltage V on the load resistor R_R＝-V₂＝-V_dc

The working state 9: switch tube T₁And T₄Is in an on state, the other switch tubes are in an off state, and the voltage V on the load resistor R_R＝-V₁-V₂-V₄＝-4V_dc。

Claims

1. A novel nine-level inverter comprises a DC power supply V₁、V₂、V₃、V₄IGBT switch tube T₁、T₂、T₃、T₄、T₅、T₆Diode D₁、D₂、D₃、D₄、D₅、D₆、D₇、D₈And a load resistor R, characterized by a switching tube T₁Collector and DC power supply V₂Positive electrode and switching tube T₃Is connected with the collector of the switching tube T₁Emitter and switch tube T₂Collector electrode of (2), diode D₁Anode of (2), diode D₂Is connected with the load, and a switching tube T₂Collector and switch tube T₁Emitter, diode D₁Anode of (2), diode D₂Is connected with the load, and a switching tube T₂Emitter and power supply V₁Negative electrode of (2) and switching tube T₄Is connected with the emitting electrode of the switching tube T₃Collector and switch tube T₁Collector and dc power supply V₂Is connected with the positive pole of the switching tube T₃Emitter and DC power supply T₃Is connected with the negative pole of the switching tube T₄Collector and DC power supply V₄Is connected with the positive pole of the switching tube T₄Emitter and switch tube T₂Emitter and dc power supply V₁Is connected with the negative pole of the switching tube T₅Collector and diode D₁、D₄Is connected with the negative pole of the switching tube T₅Emitter and diode D₂、D₃The positive pole of the switch tube T is connected with the positive pole of the anode₆Collector and diode D₅、D₈Is connected with the negative pole of the switching tube T₆Emitter and diode D₆、D₇The positive electrodes of (a) and (b) are connected.

2. The novel nine-level inverter as claimed in claim 1, wherein the inverter switching tube T₅And diode D₁、D₂、D₃、D₄Switch tube T6 and diode D₅、D₆、D₇、D₈Two bidirectional switches are formed.

3. A novel nine-level inverter as claimed in claim 1, wherein only 2 of the 6 switching tubes of the inverter are in conduction at any one time.

4. A novel nine-level inverter as claimed in claim 1, wherein the inverter uses a lower dc power source to obtain a higher output voltage.

5. The novel nine-level inverter as claimed in claim 1, wherein the inverter can reduce switching frequency of the switching tube and prolong the service life of the switching tube.

6. A novel nine-level inverter as claimed in claim 1, characterized in that the dc supply voltage V of the inverter is₁、V₂、V₃、V₄The voltage value ratio is 1:1:2: 2.