CN201937492U

CN201937492U - Low-voltage seven-level inverter

Info

Publication number: CN201937492U
Application number: CN2011200105819U
Authority: CN
Inventors: 费万民; 黄银银; 张艳莉
Original assignee: Nanjing Normal University
Current assignee: Nanjing Normal University
Priority date: 2011-01-14
Filing date: 2011-01-14
Publication date: 2011-08-17
Anticipated expiration: 2021-01-14

Abstract

The utility model discloses a low-voltage seven-level inverter, which belongs to the technical field of power electronics and comprises a two-level inverter and a three-terminal network, wherein the two-level inverter consists of a direct-current power source and four MOSFETs (metal-oxide-semiconductor field effect transistors), and the three-terminal network consists of three energy storage capacitors and four power MOSFETs. The levels of 0, E/3, 2E/3, E, -E/3, -2E/3, -E can be obtained from a load by selecting proper switches for controlling on-off states. The seven-level inverter can be applied to occasions for high-fidelity power amplification and the like, is capable of remarkably improving the fidelity and the power conversion efficiency of a power amplifier, and has the remarkable advantages of high output waveform quality, less controllable elements in a conduction state of each mode, simplicity in control, easiness in realization and the like.

Description

A kind of low-voltage seven electrical level inverters

Technical field

The utility model relates to a kind of low harmonic power converter that is applied to the high-fidelity power amplification, belongs to electric and electronic technical field, is used for the high-performance power amplifier in the low voltage range.

Background technology

The high-power audio power amplifier is widely used in occasions such as television transmitting station, broadcast transmitting station, television set, high power acoustics, present existing technology is to adopt two traditional level power converter structures, it is the D class A amplifier A, as shown in Figure 1, wherein, T1-T4 is the MOSFET pipe with built-in backward diode, because the non-individual devices of backward diode, so, do not mark separately.Z is load.Traditional two-level inverter is compared with novel multi-electrical level inverter, and bandwidth is narrower, easily distortion, and the switching frequency height, power conversion efficiency is lower.Existing multi-level converter main circuit topological structure has the diode clamp multi-level converter, the striding capacitance multi-level converter, various cascade multilevel converters etc., in the main circuit that adopts these topological structures, have at least 4 power switchs to be in conducting state constantly in each that power output arranged, in the low voltage application occasion, the ratio that these on-state tube voltage drops account for output voltage is excessive, thereby cause power conversion efficiency to reduce, and, because existing multi-level converter is mainly used in mesohigh Power Conversion occasion, therefore, at each constantly, all to rely on a plurality of pipe series connection that are in off state, improve the output voltage grade of whole device, thereby it is comparatively complicated to cause its circuit to be formed, used power switch quantity is more.That is to say, existing multi-level power converter is used the low-voltage occasion, then cause unnecessary complexity of system and low power conversion efficiency.

Summary of the invention

The purpose of this utility model is to overcome above-mentioned defective of the prior art, and a kind of seven electrical level inverters that are applicable to the low-voltage occasion are provided, and can solve the technical problem that traditional two-level inverter, multi-electrical level inverter exist in the low voltage application occasion.

To achieve these goals, the technical solution adopted in the utility model is as follows:

A kind of low-voltage seven electrical level inverters, comprise by DC power supply and four MOSFET and manage two-level inverter, three energy storage capacitors of forming and the three-terminal network of being made up of four power MOSFET tubes, the drain electrode of dc power anode, the first energy storage capacitor positive pole, a MOSFET pipe, the drain electrode of the 3rd MOSFET pipe are connected together; The source electrode of described dc power cathode, the 3rd energy storage capacitor negative pole, the 2nd MOSFET pipe, the source electrode of the 4th MOSFET pipe are connected together; The drain electrode anodal and first power MOSFET tube of the negative pole of described first energy storage capacitor, second energy storage capacitor is connected together; The drain electrode anodal and the 3rd power MOSFET tube of the negative pole of described second energy storage capacitor, the 3rd energy storage capacitor is connected together; The source electrode of described first power MOSFET tube and second power MOSFET tube is connected together; The source electrode of described the 3rd power MOSFET tube and the 4th power MOSFET tube is connected together; After the drain electrode of described second power MOSFET tube and the 4th power MOSFET tube is connected, be connected together with the source electrode of load, a described MOSFET pipe, the drain electrode of the 2nd MOSFET pipe.

With the low voltage application is target, the utility model proposes a kind of seven new electrical level inverters, has following beneficial effect: output waveform quality height, and power conversion performance is good; The controlled member that is in conducting state under each pattern is few, efficient is high; Control is simple, be easy to significant advantage such as realization.

Description of drawings

Fig. 1 is the circuit diagram of two level power converters traditional in the prior art.

Fig. 2 is the circuit diagram of the utility model low-voltage seven electrical level inverters.

Embodiment

Below in conjunction with drawings and Examples, the utility model is described in further details.

As shown in Figure 2, inverter of the present utility model comprises by DC power supply E and four having the three-terminal network that traditional two-level inverter (as shown in Figure 1), energy storage capacitor C1-C3, power MOSFET tube T5-T8 that the MOSFET pipe T1-T4 of built-in backward diode forms form; Wherein, positive source, capacitor C1 positive pole are connected together with the drain electrode of MOSFET pipe T1, T3; The source electrode of power cathode, capacitor C3 negative pole and MOSFET pipe T2, T4 is connected together; The drain electrode of the positive pole of the negative pole of capacitor C1, capacitor C2 and MOSFET pipe T5 is connected together; The drain electrode of the positive pole of the negative pole of capacitor C2, capacitor C3 and MOSFET pipe T7 is connected together; The source electrode of MOSFET pipe T5 and T6 is connected together; The source electrode of MOSFET pipe T7 and T8 is connected together; After the drain electrode of MOSFET pipe T6 and T8 is connected, be connected together with the source electrode of load Z, MOSFET pipe T1, the drain electrode of MOSFET pipe T2.

When MOSFET pipe T1, T4 conducting, other pipe shutoff, the voltage on the load Z is supply voltage E; When MOSFET pipe T4, T5 conducting, other pipe shutoff, the voltage on the load Z is 2/3 of supply voltage E; When MOSFET pipe T7 and T4 conducting and the shutoff of other pipe, the voltage on the load Z is 1/3 of supply voltage E; When MOSFET pipe T2, T4 conducting and other pipe turn-offed, the voltage on the load Z was 0; When MOSFET pipe T2, T3 conducting, other pipe shutoff, the voltage on the load Z is negative supply voltage-E; When MOSFET pipe T3 and T6 conducting, when other pipe turn-offs, the voltage on the load Z is-E/3; When MOSFET pipe T8 and T3 conducting and the shutoff of other pipe, the voltage on the load Z is-2E/3.Promptly by selecting the state of suitable switch through and off, can obtain 0 on the load Z, E/3,2E/3, E ,-E/3 ,-2E/3 ,-seven level such as E.

Seven electrical level inverters of the present utility model can be applied to occasions such as high-fidelity power amplification, can significantly improve the fidelity and the power conversion efficiency of power amplifier.

Claims

1. low-voltage seven electrical level inverters, comprise by DC power supply and four MOSFET and manage two-level inverter, three energy storage capacitors of forming and the three-terminal network of forming by four power MOSFET tubes, it is characterized in that the drain electrode of dc power anode, first energy storage capacitor (C1) positive pole, MOSFET pipe (T1), the drain electrode of the 3rd MOSFET pipe (T3) are connected together; The source electrode of described dc power cathode, the 3rd energy storage capacitor (C3) negative pole, the 2nd MOSFET pipe (T2), the source electrode of the 4th MOSFET pipe (T4) are connected together; The drain electrode of the positive pole of the negative pole of first energy storage capacitor (C1), second energy storage capacitor (C2) and the 5th power MOSFET tube (T5) is connected together; The drain electrode of the positive pole of the negative pole of second energy storage capacitor (C2), the 3rd energy storage capacitor (C3) and the 7th power MOSFET tube (T7) is connected together; The source electrode of the 5th power MOSFET tube (T5) and the 6th power MOSFET tube (T6) is connected together; The source electrode of the 7th power MOSFET tube (T7) and the 8th power MOSFET tube (T8) is connected together; After the drain electrode of the 6th power MOSFET tube (T6) and the 8th power MOSFET tube (T8) is connected, be connected together with the source electrode of load (Z), described MOSFET pipe (T1), the drain electrode of the 2nd MOSFET pipe (T2).