阅读说明：本技术 逆变器、逆变器电路及其构建方法 (Inverter, inverter circuit and construction method thereof ) 是由 汪洪亮 邱晓东 岳秀梅 罗安 于 2020-05-22 设计创作，主要内容包括：本申请公开了一种逆变器、逆变器电路及其构建方法。其中,逆变器电路,包括：相连接的逆变电路和分频电路；逆变电路,用于通过控制开关器件将输入的直流电变换成阶梯波并输出给分频电路；阶梯波包含多个不同频率的正弦波,各正弦波的频率为开关器件的开关频率的倍数；分频电路,用于滤除阶梯波中包含的不符合目标频率的正弦波,且提取阶梯波中包含的符合目标频率的正弦波作为输出的交流电；开关器件的开关频率为目标频率的1/N,N为大于1的正整数。通过一个较低的开关频率,就可以得到一个较高的交流电的频率,与相关技术相比,一方面,突破了开关器件的最高开关频率的制约,另一方面,也减少了开关器件的损耗。(The application discloses an inverter, an inverter circuit and a construction method thereof. Wherein, inverter circuit includes: the inverter circuit and the frequency division circuit are connected; the inverter circuit is used for converting the input direct current into step waves by controlling the switching device and outputting the step waves to the frequency dividing circuit; the step wave comprises a plurality of sine waves with different frequencies, and the frequency of each sine wave is a multiple of the switching frequency of the switching device; the frequency dividing circuit is used for filtering sine waves which do not accord with the target frequency and are contained in the step waves, and extracting the sine waves which accord with the target frequency and are contained in the step waves as output alternating current; the switching frequency of the switching device is 1/N of the target frequency, and N is a positive integer greater than 1. Compared with the related technology, on one hand, the limitation of the highest switching frequency of the switching device is broken through, and on the other hand, the loss of the switching device is also reduced.)

1. An inverter circuit, comprising: the inverter circuit and the frequency division circuit are connected;

the inverter circuit is used for converting the input direct current into step waves by controlling the switching device and outputting the step waves to the frequency dividing circuit; the step wave comprises a plurality of sine waves with different frequencies, and the frequency of each sine wave is a multiple of the switching frequency of the switching device;

the frequency dividing circuit is used for filtering the sine wave which does not accord with the target frequency and is contained in the step wave, and extracting the sine wave which accords with the target frequency and is contained in the step wave as output alternating current;

the switching frequency of the switching device is 1/N of the target frequency, and N is a positive integer greater than 1.

2. The inverter circuit of claim 1, wherein the frequency divider circuit comprises an L C resonant cell.

3. The inverter circuit according to claim 2, wherein the frequency dividing circuit comprises:

a first output terminal and a second output terminal for connecting a load;

the first input end and the second input end of the inverter circuit are respectively connected;

a first L C resonant cell, a second L C resonant cell, and a third L C resonant cell;

wherein a first end of the first L C resonant unit cell is connected to the first input terminal, and a second end is respectively connected to a first end of the second L C resonant unit cell and a first end of the third L C resonant unit cell;

a second end of the second L C resonant unit is connected with the first output end;

and the second end of the third L C resonant unit is respectively connected with the second input end and the second output end.

4. The inverter circuit according to claim 2, wherein the frequency dividing circuit comprises:

a first output terminal and a second output terminal for connecting a load;

the first input end and the second input end of the inverter circuit are respectively connected;

a fourth L C resonance cell and a fifth L C resonance cell;

wherein a first terminal of the fourth L C resonant cell is connected to the first input terminal and a first terminal of the fifth L C resonant cell, respectively, and a second terminal is connected to the first output terminal;

a second terminal of the fifth L C resonant unit is connected to the second input terminal and the second output terminal, respectively.

5. The inverter circuit according to claim 2, wherein the frequency dividing circuit comprises:

a first output terminal and a second output terminal for connecting a load;

the first input end and the second input end of the inverter circuit are respectively connected;

a sixth L C resonance unit and a seventh L C resonance unit;

wherein a first end of the sixth L C resonant unit is connected to the first input terminal, and a second end is connected to a first end and the first output terminal of the seventh L C resonant unit, respectively;

a second end of the seventh L C resonant unit is connected to the second input terminal and the second output terminal, respectively.

6. The inverter circuit according to claim 5, wherein the sixth L C resonant unit comprises a first inductor, a second inductor and a first capacitor, wherein a first end of the first inductor is used as a first end of the sixth L C resonant unit, a first end of the first inductor is connected with a first end of the first capacitor, and second ends of the first inductor and the second inductor are respectively connected with a second end of the first capacitor and a first end of the second inductor;

the seventh L C resonant unit comprises a third inductor, wherein the first end of the third inductor is used as the first end of the seventh L C resonant unit, and the second end of the third inductor is used as the second end of the seventh L C resonant unit.

7. The inverter circuit according to claim 5, wherein the sixth L C resonant unit comprises a fourth inductor and a second capacitor, a first end of the fourth inductor is used as a first end of the sixth L C resonant unit, a second end of the fourth inductor is connected with a first end of the second capacitor, a second end of the second capacitor is used as a second end of the sixth L C resonant unit;

the seventh L C resonant unit comprises a fifth inductor and a third capacitor, wherein the first end of the fifth inductor is used as the first end of the seventh L C resonant unit, the second end of the fifth inductor is connected with the first end of the third capacitor, and the second end of the third capacitor is used as the second end of the seventh L C resonant unit.

8. An inverter comprising the inverter circuit according to any one of claims 1 to 7.

9. A method of constructing an inverter circuit according to any one of claims 1 to 7, comprising:

determining the target frequency of the alternating current to be output by the frequency dividing circuit;

determining the switching frequency of a switching device in the inverter circuit according to the target frequency;

determining parameters of a switching device according to the switching frequency so as to build an inverter circuit according to the determined parameters of the switching device;

judging whether the content of the sine waves which are contained in each step wave and meet the target frequency meets the requirement or not aiming at a plurality of preset step waves with different shapes;

acquiring a plurality of different topological structures of a preset frequency division circuit for the step wave meeting the requirement, and solving element parameters which can enable the frequency division circuit to meet preset constraint conditions based on each topological structure;

and selecting one topological structure from the topological structures with solutions, so that a frequency division circuit built based on the selected topological structure and the obtained element parameters can filter the sine waves which are contained in the step wave and do not accord with the target frequency and extract the sine waves which are contained in the step wave and accord with the target frequency.

10. The method for constructing an inverter circuit according to claim 9, wherein the separately obtaining the frequency and the content of the sine wave included in each of the step waves comprises:

and for each step wave, carrying out Fourier transform, and decomposing to obtain the frequency and the content of the sine wave contained in the step wave.

Technical Field

The present disclosure relates to the field of inverter technologies, and in particular, to an inverter, an inverter circuit, and a method for constructing the inverter circuit.

Background

An inverter is a converter that converts an input direct current into an alternating current.

Disclosure of Invention

The present application aims to provide an inverter, an inverter circuit and a construction method thereof, so as to solve the problems that in the related art, the frequency of sinusoidal alternating current output by the inverter is limited by the switching frequency of a switching device, and the frequency of the switching device is increased to cause the loss of the switching device to be increased.

The purpose of the application is realized by the following technical scheme:

an inverter circuit comprising: the inverter circuit and the frequency division circuit are connected;

the inverter circuit is used for converting the input direct current into step waves by controlling the switching device and outputting the step waves to the frequency dividing circuit; the step wave comprises a plurality of sine waves with different frequencies, and the frequency of each sine wave is a multiple of the switching frequency of the switching device;

the frequency dividing circuit is used for filtering the sine wave which does not accord with the target frequency and is contained in the step wave, and extracting the sine wave which accords with the target frequency and is contained in the step wave as output alternating current;

the switching frequency of the switching device is 1/N of the target frequency, and N is a positive integer greater than 1.

Optionally, the frequency dividing circuit comprises an L C resonant cell.

Optionally, the frequency dividing circuit includes:

a first output terminal and a second output terminal for connecting a load;

the first input end and the second input end of the inverter circuit are respectively connected;

a first L C resonant cell, a second L C resonant cell, and a third L C resonant cell;

wherein a first end of the first L C resonant unit is connected to the first input terminal, and a second end is respectively connected to a first end of the second L C resonant unit and a first end of the third L C resonant unit;

a second end of the second L C resonant unit is connected with the first output end;

and the second end of the third L C resonant unit is respectively connected with the second input end and the second output end.

Optionally, the frequency dividing circuit includes:

a first output terminal and a second output terminal for connecting a load;

the first input end and the second input end of the inverter circuit are respectively connected;

a fourth L C resonance cell and a fifth L C resonance cell;

wherein a first terminal of the fourth L C resonant cell is connected to the first input terminal and a first terminal of the fifth L C resonant cell, respectively, and a second terminal is connected to the first output terminal;

a second terminal of the fifth L C resonant unit is connected to the second input terminal and the second output terminal, respectively.

Optionally, the frequency dividing circuit includes:

a first output terminal and a second output terminal for connecting a load;

the first input end and the second input end of the inverter circuit are respectively connected;

a sixth L C resonance unit and a seventh L C resonance unit;

wherein a first end of the sixth L C resonant unit is connected to the first input terminal, and a second end is connected to a first end and the first output terminal of the seventh L C resonant unit, respectively;

a second end of the seventh L C resonant unit is connected to the second input terminal and the second output terminal, respectively.

Optionally, the sixth L C resonance unit comprises a first inductor, a second inductor and a first capacitor, wherein a first end of the first inductor is used as a first end of the sixth L C resonance unit, a first end of the first inductor is connected with a first end of the first capacitor, and second ends of the first inductor are respectively connected with a second end of the first capacitor and a first end of the second inductor;

the seventh L C resonant unit comprises a third inductor, wherein the first end of the third inductor is used as the first end of the seventh L C resonant unit, and the second end of the third inductor is used as the second end of the seventh L C resonant unit.

Optionally, the sixth L C resonant unit includes a fourth inductor and a second capacitor, a first end of the fourth inductor is used as a first end of the sixth L C resonant unit, and a second end of the fourth inductor is connected to a first end of the second capacitor;

the seventh L C resonant unit comprises a fifth inductor and a third capacitor, wherein the first end of the fifth inductor is used as the first end of the seventh L C resonant unit, the second end of the fifth inductor is connected with the first end of the third capacitor, and the second end of the third capacitor is used as the second end of the seventh L C resonant unit.

An inverter comprising an inverter circuit as claimed in any one of the preceding claims.

A method of constructing an inverter circuit as claimed in any one of the preceding claims, comprising:

determining the target frequency of the alternating current to be output by the frequency dividing circuit;

determining the switching frequency of a switching device in the inverter circuit according to the target frequency;

determining parameters of a switching device according to the switching frequency so as to build an inverter circuit according to the determined parameters of the switching device;

judging whether the content of the sine waves which are contained in each step wave and meet the target frequency meets the requirement or not aiming at a plurality of preset step waves with different shapes;

acquiring a plurality of different topological structures of a preset frequency division circuit for the step wave meeting the requirement, and solving element parameters which can enable the frequency division circuit to meet preset constraint conditions based on each topological structure;

and selecting one topological structure from the topological structures with solutions, so that a frequency division circuit built based on the selected topological structure and the obtained element parameters can filter the sine waves which are contained in the step wave and do not accord with the target frequency and extract the sine waves which are contained in the step wave and accord with the target frequency.

Optionally, respectively acquire every frequency and content of the sinusoidal wave that the ladder wave contains, include:

and for each step wave, carrying out Fourier transform, and decomposing to obtain the frequency and the content of the sine wave contained in the step wave.

This application adopts above technical scheme, has following beneficial effect:

the inverter circuit converts an input direct current into a step wave by controlling a switching device, the step wave is subjected to Fourier transform and can be decomposed into sine waves with different frequencies, the sine waves comprise sine waves with the lowest frequency consistent with the switching frequency of the switching device and also comprise sine waves with the frequency greater than the switching frequency and being multiples of the switching frequency, L C resonance has the following characteristics that L C series resonance impedance is zero (equivalent to short circuit), L C parallel impedance is infinite (equivalent to open circuit), a resonance network is constructed on the basis of the construction, the output gain of the sine waves with the target frequency tends to be maximum, the output gain of the sine waves with other frequencies obtained by the Fourier transform decomposition tends to be zero, the sine waves with the target frequency can be output to a load instead of the sine waves with the target frequency, on the basis, a novel concept, namely frequency division is provided in the scheme of the inverter circuit, the switching frequency of the switching device is 1/N of the target frequency of the actually required alternating current, N is a positive integer greater than 1, in other words, the target frequency is N times of the switching frequency, the switching frequency is extracted, the alternating current is extracted as a target frequency of the alternating current, the target frequency division, the alternating current is extracted by the frequency division technology, the step wave, the alternating current output is reduced by the target frequency, and the alternating current output by the high frequency, the target frequency, the high frequency, the alternating current frequency is reduced by the high frequency, the target frequency, the high frequency of the alternating current frequency, the alternating current frequency is further the alternating current frequency.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic view of a step wave.

Fig. 2 is a schematic view of another step wave.

Fig. 3 is a schematic view of another step wave.

Fig. 4 is a schematic structural diagram of an inverter circuit according to an embodiment of the present application.

Fig. 5 is a schematic structural diagram of a frequency division circuit according to another embodiment of the present application.

Fig. 6 is a schematic structural diagram of a frequency division circuit according to another embodiment of the present application.

Fig. 7 is a schematic structural diagram of a frequency division circuit according to another embodiment of the present application.

Fig. 8 is a schematic structural diagram of a frequency division circuit according to another embodiment of the present application.

Fig. 9 is a schematic structural diagram of a frequency division circuit according to another embodiment of the present application.

Fig. 10 is a schematic structural diagram of an inverter circuit according to another embodiment of the present application.

Fig. 11 is a schematic diagram of a waveform output according to another embodiment of the present application.

Fig. 12 is a flowchart of a method for constructing an inverter circuit according to another embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the technical solutions of the present application will be described in detail below. It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the examples given herein without making any creative effort, shall fall within the protection scope of the present application.

An inverter is a converter that converts an input direct current into an alternating current.