阅读说明：本技术 三相功率因素校正装置 (Three-phase power factor correcting device ) 是由 钟郁纬 刘亚哲 黄士荣 王士昕 于 2021-10-25 设计创作，主要内容包括：本发明公开了一种三相功率因素校正装置,其包括一三相切换开关组、三个电感器与三个滤波电容器。三相切换开关组耦接于一第一输出端与一第二输出端之间。所有电感器耦接三相切换开关组。三相切换开关组通过电感器接收三相电磁干扰滤除电压,并转换三相电磁干扰滤除电压为一直流电压。所有滤波电容器分别耦接所有电感器,并耦接第二输出端,每一滤波电容器连接于对应的电感器与第二输出端之间,所有滤波电容器滤除三相电磁干扰滤除电压的共模噪声,以降低危险发生的机率。(The invention discloses a three-phase power factor correction device which comprises a three-phase change-over switch group, three inductors and three filter capacitors. The three-phase switch set is coupled between a first output end and a second output end. All the inductors are coupled with the three-phase switch group. The three-phase change-over switch group receives the three-phase electromagnetic interference filtering voltage through the inductor and converts the three-phase electromagnetic interference filtering voltage into a direct current voltage. All the filter capacitors are respectively coupled with all the inductors and the second output end, each filter capacitor is connected between the corresponding inductor and the second output end, and all the filter capacitors filter the common mode noise of the three-phase electromagnetic interference filtering voltage so as to reduce the probability of danger.)

1. A three-phase power factor correction device, comprising:

a three-phase switch set coupled between a first output end and a second output end;

the three inductors are coupled with the three-phase change-over switch set, wherein the three-phase change-over switch set is used for receiving the three-phase electromagnetic interference filtering voltage through the inductors and converting the three-phase electromagnetic interference filtering voltage into a direct-current voltage; and

and three filter capacitors respectively coupled to all the inductors and the second output terminal, each filter capacitor being connected between the corresponding inductor and the second output terminal, wherein the filter capacitors are configured to filter common mode noise of the three-phase emi filtered voltage.

2. The apparatus of claim 1, further comprising three first diodes, anodes of which are coupled to the second output terminal, cathodes of which are coupled to all the filter capacitors, respectively, wherein the first diodes are coupled to all the filter capacitors in parallel, respectively.

3. The apparatus of claim 2, further comprising three second diodes, anodes of the three second diodes being coupled to cathodes of all the first diodes, respectively, and cathodes of the three second diodes being coupled to the first output terminal.

4. The three-phase power factor correction device of claim 1, wherein the three-phase change-over switch group comprises:

two first electronic switches coupled in series between the first output terminal and the second output terminal;

two second electronic switches coupled in series between the first output terminal and the second output terminal; and

and two third electronic switches coupled in series between the first output terminal and the second output terminal, wherein a node between the two first electronic switches, a node between the two second electronic switches, and a node between the third electronic switches are coupled to all the inductors, respectively, and the first electronic switch, the second electronic switch, and the third electronic switch are configured to receive the three-phase emi filtered voltage and convert the three-phase emi filtered voltage into a dc voltage.

5. The apparatus of claim 4, wherein the first electronic switch, the second electronic switch, and the third electronic switch are N-channel MOSFETs.

6. The apparatus of claim 1, further comprising a voltage stabilizing capacitor coupled between the first output terminal and the second output terminal.

7. The apparatus of claim 1, wherein the inductor is coupled to a three-phase voltage source via an electromagnetic interference filter circuit, the three-phase voltage source is configured to generate a three-phase voltage, and the electromagnetic interference filter circuit is configured to receive the three-phase voltage and filter an electromagnetic interference signal of the three-phase voltage to generate a three-phase EMI filtered voltage.

8. The apparatus of claim 7, wherein the EMI filter circuit includes a plurality of capacitors and a plurality of inductors.

9. The apparatus of claim 1, wherein the three-phase switch bank is coupled to a dc-to-dc converter.

10. The apparatus of claim 9, wherein the dc voltage converter is a half-bridge dc voltage converter or a full-bridge dc voltage converter.

Technical Field

The present invention relates to a calibration device, and more particularly, to a three-phase power factor calibration device.

Background

The power factor refers to a relationship between the effective power and the total power consumption, i.e. a ratio of the effective power divided by the total power consumption, and in general, the power factor can be used to measure the degree of power utilization, and when the value of the power factor is larger, it represents that the power utilization is higher. The power factor corrector applied to the power supply is mostly used for controlling and adjusting the time and wave form of alternating current input, so that the alternating current input time and the wave form are consistent with those of direct current voltage as much as possible, the power factor value is close to 1, and the power consumed by a power equipment system is prevented from exceeding the specification and generating unnecessary interference.

As can be seen from the above, the low power factor represents low power efficiency, and the lower the power efficiency represents higher power consumption in the distribution network; if the lower power factor is not corrected and improved, the power company needs to provide virtual work irrelevant to the work besides the effective power, and correspondingly, the consumption of power transmission equipment such as a generator, a converter, a transmission tool, even a cable and the like needs to be increased to make up for the lower power factor; therefore, most electronic devices have power factor correctors to help improve their own energy utilization.

Fig. 1 is a circuit diagram of a three-phase power factor correction device in the prior art. Referring to fig. 1, the six-switch three-phase power factor correction circuit is composed of six power switches 10, each bridge arm has two upper and lower power switches 10, and each phase current can be controlled by the two power switches 10 on the bridge arm. Since the sum of the currents of the three phases is zero, it is sufficient to control only the currents of two phases, and thus in practical applications, the phase having the largest absolute value of voltage is not controlled, and only the other two phases are selected for control. This has the advantage of reducing the number of switching actions and thus the overall switching losses. However, the six-switch three-phase power factor correction circuit has too many switches, complex control and high cost, and when common-mode noise occurs, the two series-connected power switches 10 on each bridge arm have the risk of direct connection and short circuit, so that the requirement on the reliability of power drive control is high.

Therefore, the present invention provides a three-phase power factor correction device for solving the above-mentioned problems in the prior art.

Disclosure of Invention

The present invention is directed to a three-phase power factor corrector, which effectively suppresses electromagnetic interference caused by common mode noise, reduces the risk, and reduces the number of common mode inductors and common mode capacitors of an electromagnetic interference circuit, thereby facilitating circuit design, reducing cost, and improving voltage supply efficiency.

To achieve the above objective, the present invention provides a three-phase power factor correction device, which includes a three-phase switch set, three inductors and three filter capacitors. The three-phase switch set is coupled between a first output end and a second output end. All the inductors are coupled with the three-phase switch group. The three-phase change-over switch group receives the three-phase electromagnetic interference filtering voltage through the inductor and converts the three-phase electromagnetic interference filtering voltage into a direct current voltage. All the filter capacitors are respectively coupled to all the inductors and to the second output terminal, each filter capacitor is connected between the corresponding inductor and the second output terminal, and all the filter capacitors filter the common mode noise of the three-phase electromagnetic interference filtering voltage.

In an embodiment of the invention, the three-phase power factor correction device further includes three first diodes, anodes of the three first diodes are coupled to the second output terminal, cathodes of all the first diodes are coupled to all the filter capacitors, respectively, wherein all the first diodes are coupled to all the filter capacitors in parallel, respectively.

In an embodiment of the invention, the three-phase power factor correction device further includes three second diodes, anodes of the three second diodes are respectively coupled to cathodes of all the first diodes, and cathodes of all the second diodes are coupled to the first output terminal.

In an embodiment of the invention, the three-phase switch set includes two first electronic switches, two second electronic switches, and two third electronic switches. All the first electronic switches are coupled in series between the first output end and the second output end. All the second electronic switches are coupled in series between the first output end and the second output end. All the third electronic switches are coupled in series between the first output end and the second output end. And the nodes between the two first electronic switches, the nodes between the two second electronic switches and the nodes between the two third electronic switches are respectively coupled with all the inductors, wherein all the first electronic switches, all the second electronic switches and all the third electronic switches are used for receiving the three-phase electromagnetic interference filtering voltage and converting the three-phase electromagnetic interference filtering voltage into direct-current voltage.

In an embodiment of the invention, the first electronic switch, the second electronic switch and the third electronic switch are N-channel mosfets.

In an embodiment of the invention, the three-phase power factor correction device further includes a voltage stabilizing capacitor coupled between the first output terminal and the second output terminal.

In an embodiment of the invention, the inductor is coupled to a three-phase voltage source through an electromagnetic interference filter circuit, the three-phase voltage source is used for generating a three-phase voltage, and the electromagnetic interference filter circuit is used for receiving the three-phase voltage and filtering electromagnetic interference signals of the three-phase voltage to generate a three-phase electromagnetic interference filtering voltage.

In one embodiment of the present invention, the EMI filter circuit includes a plurality of capacitors and a plurality of inductors.

In an embodiment of the present invention, the three-phase switch set is coupled to a dc voltage converter.

In an embodiment of the invention, the dc voltage converter is a half-bridge dc voltage converter or a full-bridge dc voltage converter.

Based on the above, the three-phase power factor correction device utilizes the filter capacitor to filter the common mode noise of the three-phase electromagnetic interference filtering voltage, so as to effectively suppress the electromagnetic interference caused by the common mode noise, reduce the probability of danger occurrence, reduce the number of the common mode inductor and the common mode capacitor of the electromagnetic interference circuit, and further facilitate the design of the circuit, reduce the cost and improve the efficiency of voltage supply.

Drawings

Fig. 1 is a circuit diagram of a three-phase power factor correction device in the prior art.

Fig. 2 is a circuit diagram of a three-phase power factor correction device according to a first embodiment of the present invention.

Fig. 3 is a circuit diagram of a three-phase power factor correction device according to a second embodiment of the present invention.

Description of the symbols:

10 power switch 12 three-phase power factor correcting unit

14 three-phase change-over switch group 16 inductor

18 filter capacitor 20 electromagnetic interference filter circuit

22 three-phase voltage source 24 first phase voltage source

26 second phase voltage source 28 third phase voltage source

30 first electronic switch 32 second electronic switch

34 third electronic switch 36 controller

38 voltage-stabilizing capacitor 40 DC voltage converter

42 first diode 44 second diode

Detailed Description

Embodiments of the invention will be further illustrated by the following description in conjunction with the related drawings. Wherever possible, the same reference numbers will be used throughout the drawings and the description to refer to the same or like parts. In the drawings, the shape and thickness may be exaggerated for simplicity and convenience. It is to be understood that elements not specifically shown in the drawings or described in the specification are of a type well known to those of ordinary skill in the art. Many variations and modifications may be made by one of ordinary skill in the art in light of the teachings of the present invention.

Unless specifically stated otherwise, some conditional clauses or words, such as "may", "might", or "might", are generally intended to convey that the embodiments of the disclosure have, but may also be interpreted as having, features, elements, or steps that may not be required. In other embodiments, these features, elements, or steps may not be required.

Reference hereinafter to "one embodiment" or "an embodiment" means that a particular element, structure, or feature described in connection with at least one embodiment is referred to. Thus, the appearances of the phrase "one embodiment" or "an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

Certain terms are used throughout the description and following claims to refer to particular components. However, those of ordinary skill in the art will appreciate that the various elements may be referred to by different names. The specification and claims do not intend to distinguish between components that differ in name but not function. In the description and claims, the terms "include" and "comprise" are used in an open-ended fashion, and thus should be interpreted to mean "include, but not limited to. Further, "coupled" herein includes any direct and indirect connection. Therefore, if a first element is coupled to a second element, the first element may be directly connected to the second element through an electrical connection or a signal connection such as wireless transmission or optical transmission, or may be indirectly connected to the second element through another element or a connection means.

The present invention is described with respect to the following examples, which are intended to be illustrative only, since various changes and modifications may be made therein by those skilled in the art without departing from the spirit and scope of the present invention, the scope of the present invention should be determined only by the appended claims. Throughout the specification and claims, unless the context clearly dictates otherwise, the words "a" and "an" include the word "a" or "an" and "the" include the element or component. Furthermore, as used herein, the singular articles "a", "an", and "the" include plural referents or components unless the context clearly dictates otherwise. Also, as used in this description and throughout the claims, the meaning of "in" can include "in" and "on" unless the content clearly dictates otherwise. The words used in the specification and claims have the ordinary meaning as is accorded to such words in the art, in the context of the present invention and in the context of the particular situation disclosed herein, unless otherwise indicated. Certain terms used to describe the invention are discussed below or elsewhere in this specification to provide additional guidance to the practitioner in describing the invention. The use of examples anywhere throughout the specification, including any examples of words discussed herein, is intended merely to be illustrative, and certainly not to limit the scope or meaning of the invention or any exemplary words. As such, the present invention is not limited to the various embodiments set forth in this specification.

Fig. 2 is a circuit diagram of a three-phase power factor correction device according to a first embodiment of the present invention. A first embodiment of the three-phase power factor correction device of the present invention is described below with reference to fig. 2. The three-phase power factor correction device 12 includes a three-phase switch set 14, three inductors 16 and three filter capacitors 18. The three-phase switch set 14 is coupled between a first output terminal and a second output terminal of the three-phase power factor correction device 12, wherein the first output terminal is different from the second output terminal. All of the inductors 16 are coupled to the three-phase switch bank 14. All the filter capacitors 18 are respectively coupled to all the inductors 16 and to the second output terminal, and each filter capacitor 18 is connected between the corresponding inductor 16 and the second output terminal.

All the inductors 16 receive the three-phase electromagnetic interference filtering voltages ER, ES, and ET, respectively, so that the three-phase switch group 14 receives the three-phase electromagnetic interference filtering voltages ER, ES, and ET through the inductors 16, and converts the three-phase electromagnetic interference filtering voltages ER, ES, and ET into a direct current voltage D. Meanwhile, all the filter capacitors 18 respectively filter the common mode noise of the three-phase electromagnetic interference filtering voltages ER, ES and ET, so as to effectively suppress the electromagnetic interference caused by the common mode noise. The filter capacitor 18 can greatly reduce the common mode voltage, and the larger the capacitance value of the filter capacitor 18 is, the smaller the high frequency capacitance is, and most of the common mode current flows through the filter capacitor 18.

All of the inductors 16 may be coupled to a three-phase voltage source 22 through an emi filter circuit 20. the three-phase voltage source 22 includes a first phase voltage source 24, a second phase voltage source 26, and a third phase voltage source 28. The first phase voltage source 24, the second phase voltage source 26 and the third phase voltage source 28 are all coupled to the EMI filter circuit 20. The EMI filter circuit 20 further includes a plurality of capacitors and a plurality of inductors. The first phase voltage source 24, the second phase voltage source 26 and the third phase voltage source 28 of the three-phase voltage source 22 generate three-phase voltages R, S and T, respectively, and the emi filter circuit 20 receives the three-phase voltages R, S and T and filters emi signals of the three-phase voltages R, S and T to generate three-phase emi filtered voltages ER, ES and ET. Since the filter capacitor 18 filters the common mode noise of the three-phase emi filtered voltages ER, ES and ET, the number of common mode inductors and common mode capacitors of the emi circuit 20 can be reduced, thereby facilitating circuit design, reducing cost and improving voltage supply efficiency.

In some embodiments of the present invention, the three-phase switch set 14 may include two first electronic switches 30, two second electronic switches 32, and two third electronic switches 34. The first electronic switch 30, the second electronic switch 32 and the third electronic switch 34 can be implemented by N-channel mosfets, but the invention is not limited thereto. The first electronic switch 30 is coupled in series between the first output terminal and the second output terminal, the second electronic switch 32 is coupled in series between the first output terminal and the second output terminal, and the third electronic switch 34 is coupled in series between the first output terminal and the second output terminal. A node between the two first electronic switches 30, a node between the two second electronic switches 32 and a node between the two third electronic switches 34 are coupled to all inductors 16, respectively. The control terminals of the first electronic switch 30, the second electronic switch 32 and the third electronic switch 34 are coupled to a controller 36. The controller 36 controls the first electronic switch 30, the second electronic switch 32, and the third electronic switch 34 to receive the three-phase emi filtered voltages ER, ES, and ET, and convert the three-phase emi filtered voltages ER, ES, and ET into the dc voltage D. Since the filter capacitor 18 filters out common mode noise of the three-phase emi filtered voltages ER, ES and ET, and the common mode noise exists between the series-connected electronic switches, the risk of a shoot-through short occurring in the series-connected electronic switches can be reduced.

The three-phase power factor correction device 12 may further include a voltage stabilizing capacitor 38 coupled between the first output terminal and the second output terminal, wherein the voltage stabilizing capacitor 38 is used for stabilizing the dc voltage D. The three-phase switch set 14 may further be coupled to a dc voltage converter 40, such as a half-bridge dc voltage converter or a full-bridge dc voltage converter, through the first output terminal and the second output terminal, but the invention is not limited thereto. The dc voltage converter 40 can step down or step up the dc voltage to generate another dc voltage for the load.

Fig. 3 is a circuit diagram of a three-phase power factor correction device according to a second embodiment of the present invention. A second embodiment of the three-phase power factor correction device of the present invention is described below with reference to fig. 3. The difference between the second embodiment and the first embodiment is that the three-phase power factor correction device 12 of the second embodiment further includes three first diodes 42, the anodes of which are coupled to the second output terminal, the cathodes of all the first diodes 42 are respectively coupled to all the filter capacitors 18, and all the first diodes 42 are respectively coupled to all the filter capacitors 18 in parallel. The first diode 42 is used to prevent common mode noise from appearing at the second output terminal, and help the filter capacitor 18 to filter common mode noise of the three-phase emi filter voltages ER, ES, and ET. In addition, in the second embodiment, the three-phase power factor correction device 12 may further include three second diodes 44, anodes of which are respectively coupled to cathodes of all the first diodes 42, and cathodes of all the second diodes 44 are coupled to the first output terminal. The second diode 44 provides a charging path for the zener capacitor 38 when the three-phase power factor correction device 12 is turned on. In practical example, the first diode 42 and the second diode 44 are used when the ripple peak of the regulator capacitor 38 is less than 800 volts and the ripple valley is greater than 0 volts.

According to the embodiment, the three-phase power factor correction device utilizes the filter capacitor to filter the common mode noise of the three-phase electromagnetic interference filtering voltage so as to effectively inhibit the electromagnetic interference caused by the common mode noise, reduce the probability of danger occurrence, reduce the number of the common mode inductor and the common mode capacitor of the electromagnetic interference circuit, further facilitate the design of the circuit, reduce the cost and improve the efficiency of voltage supply.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, so that equivalent variations and modifications in the shape, structure, characteristics and spirit of the present invention as described in the claims should be included in the scope of the present invention.