CN108075648B - EMI suppression circuit, switching power supply, direct current power supply and household appliance - Google Patents
EMI suppression circuit, switching power supply, direct current power supply and household appliance Download PDFInfo
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- CN108075648B CN108075648B CN201611028062.9A CN201611028062A CN108075648B CN 108075648 B CN108075648 B CN 108075648B CN 201611028062 A CN201611028062 A CN 201611028062A CN 108075648 B CN108075648 B CN 108075648B
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/44—Circuits or arrangements for compensating for electromagnetic interference in converters or inverters
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Abstract
The embodiment of the invention provides an EMI suppression circuit for a direct-current power supply, a switching power supply, the direct-current power supply and a household appliance, and belongs to the field of electromagnetic interference suppression. The switching power supply is used for converting alternating current from an alternating current power supply into direct current output, wherein the EMI suppression circuit comprises: the first end of the filter capacitor is connected to the grounding end, and the second end of the filter capacitor is connected to the output end of the switching power supply; the first end of the first capacitor is connected between the first end of the filter capacitor and the grounding end, and the second end of the first capacitor is connected to the direct-current negative output end of the rectifier module; and the first end of the second capacitor is connected to the live wire of the alternating current power supply, and the second end of the second capacitor is connected to the second end of the filter capacitor. Therefore, an effective control EMI grounding scheme can be provided, and the EMI problem of the switching power supply can be effectively eliminated.
Description
Technical Field
The invention relates to the technical field of electronics, in particular to an EMI (electro-magnetic interference) suppression circuit for a direct-current power supply, a switching power supply, the direct-current power supply and a household appliance.
Background
Due to the defect of low conversion efficiency of the linear power supply, the switching power supply with higher conversion efficiency is favored and popularized by a plurality of household appliance manufacturers.
The working principle of the switching power supply is as follows: the switch power supply directly integrates alternating current into direct current at an input end, controls the on-off of the current by the switch tube under the action of the high-frequency oscillation circuit to form high-frequency pulse current, and then outputs stable low-voltage direct current power supply with the help of the inductor. Commonly used switching tubes are transistors, thyristors, magnetic switches, etc. When the switching tube works in a cut-off area, the switching tube is equivalent to the disconnection of a mechanical switch; when the switch tube works in a saturation region, the switch tube is equivalent to the closing of a mechanical switch.
However, when the switching power supply repeatedly works in a cut-off and saturation region, the switch is continuously opened and closed, di/dt and du/dt energy accumulation is continuously formed in a PN junction, and the transient energy is not conductive enough and can be radiated to the space in the form of electromagnetic waves to form broadband radiation electromagnetic interference of dozens of megabytes to hundreds of megabytes, so that the current household electrical appliances have the common electromagnetic interference (EMI) problem.
In order to solve the problem that conducted EMI exceeds the standard in the prior art, a common-mode interference signal filter is usually arranged on one side close to a power port to suppress a common-mode signal. When the power consumption of the household electrical products is relatively large, the EMI solution generally has the following obvious disadvantages:
the first common mode rejection device is large in size, needs to occupy a large space of a circuit board and is not beneficial to design and layout of the circuit board;
secondly, the cost of the common mode rejection device is high;
thirdly, the heat productivity of the common mode rejection device is large, which causes the heat conversion efficiency of the whole machine to be reduced.
Therefore, an EMI suppression circuit that has a low price, a simple design, a small occupied volume, and a low heat loss and can effectively suppress the EMI problem of the switching power supply is an urgent technical problem to be solved in the industry at present.
It should be noted that the above technical problems are found by the inventors of the present invention in the course of practicing the present invention.
Disclosure of Invention
An object of an embodiment of the present invention is to provide an EMI suppression circuit for a dc power supply, which has a low price, a simple design, a small occupied volume, and a low heat loss, and can effectively suppress the EMI problem of a switching power supply; it is an object of another aspect of the present invention to provide a switching power supply including the above EMI suppression circuit, a dc power supply including the above switching power supply, and a household appliance including the above dc power supply, so as to solve at least the technical problems set forth in the background art.
In order to achieve the above object, an embodiment of the present invention provides an EMI suppression circuit for a dc power supply, the dc power supply including a switching power supply and a rectifying module, wherein the switching power supply is configured to convert an ac high voltage power from an ac power supply into a dc low voltage power and output the dc low voltage power, and the rectifying module is configured to convert the ac high voltage power from the ac power supply into a dc high voltage power and output the dc high voltage power via dc positive and negative output terminals in the rectifying module, the EMI suppression circuit including:
a filter capacitor, wherein a first end of the filter capacitor is connected to a ground terminal, and a second end of the filter capacitor is connected to an output terminal of the switching power supply;
a first capacitor, a first end of which is connected to the first end of the filter capacitor, and a second end of which is connected to the dc negative output end of the rectifier module; and
and a second capacitor, wherein a first end of the second capacitor is connected to the live wire of the AC power supply, and a second end of the second capacitor is connected to the second end of the filter capacitor.
Preferably, the first capacitor and/or the second capacitor is a ceramic chip capacitor.
Preferably, the withstand voltage value of the first capacitor and/or the second capacitor is 3000VAC 220-.
Preferably, the capacitance of the first capacitor and/or the second capacitor is 101-104.
Another aspect of an embodiment of the present invention provides a switching power supply, including:
an AC-DC conversion unit for converting AC high voltage from an AC power supply into DC low voltage output; and
the EMI suppression circuit described above.
Preferably, the switching power supply further includes: and the anodes of the first rectifying diode and the second rectifying diode are respectively connected to a live wire and a zero wire of alternating voltage, and the cathodes of the first rectifying diode and the second rectifying diode are connected with the input end of the AC-DC conversion unit.
Preferably, the AC-DC conversion unit comprises one or more outputs, wherein each output is provided with an EMI suppression circuit as described above.
Another aspect of the embodiments of the present invention provides a dc power supply, including:
the switching power supply is used for converting the high-voltage alternating current of the alternating current power supply into low-voltage direct current to be output; and
and the rectification module is used for converting the high-voltage alternating current of the alternating current power supply into high-voltage direct current to be output.
Preferably, the rectifier module is a rectifier bridge.
In another aspect, an embodiment of the present invention provides a dc power supply, including: the dc power supply described above.
Preferably, the household appliance is an induction cooker, an electric cooker and other household appliances.
In the EMI suppression circuit provided in the technical scheme of the present invention, the filtering capacitor is connected across the output end of the switching power supply, and capacitors are connected across both sides of the filtering capacitor, so that the EMI suppression circuit can effectively provide a scheme for controlling EMI grounding and effectively eliminate the EMI problem of the switching power supply; compared with the common EMI filter circuit used for solving the EMI problem of the switching power supply in the prior art, the EMI suppression circuit adopting the grounding mode provided by the invention can more thoroughly eliminate the electromagnetic interference problem; and the electronic components adopted in the EMI suppression circuit are simple, the cost is low, the vigorous popularization of the EMI suppression circuit is favorably realized, and the EMI suppression circuit is particularly suitable for popularization and application in all household appliances.
Additional features and advantages of embodiments of the invention will be set forth in the detailed description which follows.
Drawings
The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the embodiments of the invention without limiting the embodiments of the invention. In the drawings:
fig. 1 is a schematic structural diagram of an EMI suppression circuit for a switching power supply according to an embodiment of the present invention;
fig. 2 is a schematic structural diagram of a switching power supply according to an embodiment of the present invention;
FIG. 3 is a schematic diagram of a DC power supply according to an embodiment of the present invention;
fig. 4 shows EMI test results for a switching power supply loop when the EMI suppression circuit in an embodiment of the invention is not included in the switching power supply loop;
fig. 5 shows EMI test results for a switching power supply circuit when the EMI suppression circuit in the embodiment of the present invention is included in the switching power supply circuit.
Description of the reference numerals
AC L AC power live wire ACN AC power zero wire
10 EMI filter circuit C1、C2Capacitor with a capacitor element
C3Filter capacitor VOOutput terminal of switch power supply
20 switching power supply D1、D2Rectifier diode
Input end V + and output end of V-rectifier bridge of AC rectifier bridge
GND ground 30 DC power supply
Detailed Description
The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.
One skilled in the art will recognize that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. It will be understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element or intervening elements may also be present. Further, "connected" or "coupled" as used herein may include wirelessly connected or wirelessly coupled. As used herein, the term "and/or" includes all or any element and all combinations of one or more of the associated listed items.
Referring to fig. 1, a schematic structural diagram of an EMI suppression circuit for a switching power supply according to an embodiment of the present invention is shown, in which a switching power supply applying the EMI suppression circuit is connected to a live line and a neutral line of an ac power supply, and is capable of converting ac power output by the ac power supply into dc power, and a rectifier module is used for converting ac high voltage power from the ac power supply into dc high voltage power and outputting the dc high voltage power via dc positive V + and negative V-output terminals of the rectifier module, and a more specific structure of the EMI suppression circuit 10 is shown in fig. 1, and includes: filter capacitor C3Capacitor C1And a capacitor C2(ii) a Filter capacitor C3One end of the filter is connected to a ground end GND and a filter capacitor C3The other end of the first switch is connected to the output end of the switching power supply; capacitor C1One end of which is connected to the filter capacitor C3One end connected to the GND side of the ground terminal, a capacitor C1The other end of the rectifier is connected to a direct current negative output end V-of the rectifier module; and a capacitor C2One end of the filter is connected to a live line AC L of an alternating current power supply, and the other end is connected to a filter capacitor C3It will be appreciated that the connection of the electronics of the EMI suppression circuit 10 to the AC mains line AC L or neutral ACN should be indirect, and more particularly the electronics may be based on the power interface for connection to the line AC L or neutral ACN to enable connection to the AC mains line AC L or neutral ACN1、C2、C3And the grounding end GND effectively filters the interference signal at the switch-in end of the switching power supply in a grounding mode, so that a strong electromagnetic interference signal generated by the switching power supply in the working process is eliminated, and particularly the interference signal with the frequency range of 30MHz-230MHz which is difficult to process by using the filtering EMI suppression circuit in the prior art can be eliminated. In some optional embodiments of the present invention, the carrier of the EMI suppression circuit is a PCB, the PCB is a single-sided board or a multi-layered board, when the carrier adopts a multi-layered board, the ground terminal in this embodiment should separately define a ground plane, and when the carrier adopts a single-sided board, the ground terminal in this embodiment should be defined as a special ground loop; therefore, the interference signal can be quickly grounded, and the elimination efficiency of the interference signal is improved.
The following will continue to disclose the model selection parameters for the various components in the EMI suppression circuit 10: capacitor C1Capacitor C2For high voltage-resistant capacitors, preferably ceramic chip capacitors, a capacitor C is required1And C2The withstand voltage value of (2) can at least exceed the voltage value of an alternating current power supply; when the circuit 10 is applied to a household electrical appliance, the withstand voltage value of the capacitor should be set to 220-3000 VAC. Capacitor C1Capacitor C2Is 101-104, it is understood that the representation of the capacitance isThe method should be well known to those skilled in the art, with a capacitance magnitude of 101 representing a 10 by 10 power PF, and a capacitance magnitude of 104 representing a 10 by 10 power PF; therefore, the normal work of the switching power supply can be guaranteed, and the switching power supply cannot be burnt out. Filter capacitor C in the embodiment of the invention3The type and capacitance of the filter capacitor C are not limited, and the filter capacitor C is connected to the output terminal of the switching power supply in the embodiment of the invention3And coupling grounding of interference signals is realized.
In order to prove that the EMI suppression circuit provided in the embodiment of the present invention has a good suppression effect on electromagnetic interference, the inventors further employ a control experiment on the embodiment of the present invention, wherein reference objects in the control experiment are: the switching power supply circuit does not comprise the EMI suppression circuit provided by the embodiment of the invention; the experimental subjects were: the switching power supply circuit identical to the reference object is different only in that the experimental object adopts the EMI suppression circuit 10 provided by the embodiment of the present invention. Fig. 4 and 5 show the EMI parameter data outputted from the reference subject and the experimental subject, respectively, and it can be seen from the comparison of the data that the EMI parameter of the reference subject exceeds the normal EMI index by 16dB, while the EMI parameter of the experimental subject has a margin of 3dB compared with the normal EMI index. It can thus be determined very intuitively: the EMI suppression circuit provided by the embodiment of the invention can effectively suppress the EMI problem of the switching power supply loop.
Referring to fig. 2, a switching power supply according to an embodiment of the present invention is shown, where the switching power supply 20 includes: AC-DC conversion unit, C1、C2And C3(ii) a Filter capacitor C3One end of the filter is connected to a ground end GND and a filter capacitor C3Is connected to the output terminal of the AC-DC conversion unit; capacitor C1One end of which is connected to the filter capacitor C3One end connected to the GND side of the ground terminal, a capacitor C1The other end of the rectifier is connected to a direct current negative output end V-of the rectifier module; and a capacitor C2One end of the rectifier module is connected to an alternating current power supply live wire AC L of the rectifier module, and the other end of the rectifier module is connected to a filter capacitor C3One end connected to an output end of the AC-DC conversion unit; wherein the AC-DC conversion unit comprises an AC-DC chip for exchanging AC power from the AC power supplyConverting the current into the direct current and outputting VOThe V isOTypically a low voltage output power supply, for powering a low voltage control circuit (not shown) connected to the switching power supply; it should be noted that when the load circuit and V are controlled at low voltageOWhen connected, capacitor C3Form a loop with the load circuit so that at C3Both upper and lower ends of (C) have noise although3Here a filter circuit, but because of the presence of this loop, C results3Both ends have noise at the upper and lower parts, and the noise intensity is generally unequal, which is very easy to be in C3Again forming a source of EMI radiation; therefore, the second step is performed in step C3Are respectively provided with a capacitor C1And a capacitor C2So that C is3The noise at both ends is quickly grounded to eliminate the EMI noise. In some optional embodiments of the present invention, the switching power supply 20 further comprises a first rectifying diode D1And a second rectifying diode D2The rectifier diode D1、D2Is connected to the live AC L of the AC power supply, the rectifier diode D1、D2Is connected to the zero line ACN of the alternating current power supply, thereby realizing the rectification of the input current of the AC-DC conversion unit and ensuring the voltage V output by the AC-DC conversion unitOQuality and conversion efficiency. In some alternative embodiments of the present invention, when the low voltage control circuit needs multiple working outputs (not shown) of the AC-DC conversion unit, the EMI suppression circuit 10 is respectively provided for each output of the AC-DC conversion unit, so that the electromagnetic interference radiation of the switching power supply loop can be reduced more effectively by filtering the electromagnetic interference signals in the respective branches.
Referring to fig. 3, which is a schematic structural diagram of a dc power supply according to another embodiment of the present invention, the dc power supply 30 includes a switching power supply portion for converting a high-voltage ac power of an ac power supply into a low-voltage dc power for output, and the detailed structure of the switching power supply portion can refer to the above embodiments, so that details are not described herein. Therefore, the electromagnetic interference generated when the low-voltage end is controlled to work is reduced by controlling the high-voltage load circuit to work at the low-voltage control end. It should be noted that the rectifier bridge in the embodiment of the present invention may also be replaced by other rectifier modules having a rectifier function, and all of them should fall within the protection scope covered by the present invention.
In another embodiment of the present invention, there is also provided a home appliance including a direct current power supply. The structure of the dc power supply can refer to the above embodiments, and therefore, will not be described herein. The direct current power supply is arranged for the household appliance, so that electromagnetic interference radiation of the household appliance can be effectively reduced. More specifically, the household appliance may be an induction cooker, an electric cooker or other household appliances, thereby reducing electromagnetic interference radiation of the household appliances.
Although the embodiments of the present invention have been described in detail with reference to the accompanying drawings, the embodiments of the present invention are not limited to the details of the above embodiments, and various simple modifications can be made to the technical solutions of the embodiments of the present invention within the technical idea of the embodiments of the present invention, and these simple modifications all belong to the protection scope of the embodiments of the present invention.
It should be noted that the various features described in the above embodiments may be combined in any suitable manner without departing from the scope of the invention. In order to avoid unnecessary repetition, the embodiments of the present invention do not describe every possible combination.
Those skilled in the art can understand that all or part of the steps in the method for implementing the above embodiments may be implemented by a program instructing related hardware, where the program is stored in a storage medium and includes several instructions to enable a (may be a single chip, a chip, etc.) or a processor (processor) to execute all or part of the steps of the method described in the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.
In addition, any combination of various different implementation manners of the embodiments of the present invention is also possible, and the embodiments of the present invention should be considered as disclosed in the embodiments of the present invention as long as the combination does not depart from the spirit of the embodiments of the present invention.
Claims (11)
1. An EMI suppression circuit for a DC power supply, the DC power supply comprising a switching power supply and a rectification module, wherein the switching power supply is used for converting AC high voltage power from an AC power supply into DC low voltage power for output, so as to supply power to a low voltage control circuit connected with the switching power supply, the rectification module is used for converting AC high voltage power from the AC power supply into DC high voltage power for output via DC positive and negative output terminals in the rectification module, so as to work with a high voltage load, and electromagnetic interference generated when the low voltage control circuit controls to work is reduced by controlling the high voltage load to work at the low voltage control circuit, the EMI suppression circuit comprising:
the first end of the filter capacitor is connected to a grounding end, and the second end of the filter capacitor is connected to the output end of the switch power supply;
a first end of the first capacitor is connected to the first end of the filter capacitor, and a second end of the first capacitor is connected to a direct current negative output end of the rectifier module; and
a second capacitor having a first terminal connected to a hot line of the AC power source and a second terminal connected to the second terminal of the filter capacitor,
the first capacitor and the second capacitor are respectively connected to the two ends of the filter capacitor, so that noise at the two ends of the filter capacitor is rapidly grounded to eliminate EMI noise.
2. The EMI suppression circuit of claim 1, wherein:
the first capacitor and/or the second capacitor are ceramic chip capacitors.
3. The EMI suppression circuit of claim 1 or 2, wherein:
the withstand voltage value of the first capacitor and/or the second capacitor is 3000 VAC-.
4. The EMI suppression circuit of claim 1 or 2, wherein:
the capacitance of the first capacitor and/or the second capacitor is 101-104.
5. A switching power supply, comprising:
an AC-DC conversion unit for converting AC high voltage from an AC power supply into DC low voltage output; and
the EMI suppression circuit of any one of claims 1-4.
6. The switching power supply according to claim 5, further comprising:
and the anodes of the first rectifying diode and the second rectifying diode are respectively connected to a live wire and a zero wire of alternating voltage, and the cathodes of the first rectifying diode and the second rectifying diode are connected with the input end of the AC-DC conversion unit.
7. The switching power supply according to claim 5, wherein the AC-DC conversion unit comprises one or more outputs, wherein each output is provided with an EMI suppression circuit according to any one of claims 1-4.
8. A direct current power supply, comprising:
a switching power supply according to any one of claims 5 to 7 for converting high voltage AC from an AC power supply to a low voltage DC output; and
and the rectifying module is used for converting the high-voltage alternating current of the alternating current power supply into high-voltage direct current to be output.
9. The direct current power supply of claim 8, wherein:
the rectifying module is a rectifying bridge.
10. A household appliance, characterized by comprising a direct current power supply according to claim 8 or 9.
11. The household appliance according to claim 10, wherein the household appliance is an induction cooker, an electric cooker or the like.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201611028062.9A CN108075648B (en) | 2016-11-18 | 2016-11-18 | EMI suppression circuit, switching power supply, direct current power supply and household appliance |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201611028062.9A CN108075648B (en) | 2016-11-18 | 2016-11-18 | EMI suppression circuit, switching power supply, direct current power supply and household appliance |
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| CN108075648A CN108075648A (en) | 2018-05-25 |
| CN108075648B true CN108075648B (en) | 2020-07-14 |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201467002U (en) * | 2009-05-22 | 2010-05-12 | 王中美 | Power supply energy-saving circuit for household appliances and office equipment |
| JP2010268623A (en) * | 2009-05-15 | 2010-11-25 | Hitachi Koki Co Ltd | Charger |
| CN102044961A (en) * | 2010-12-23 | 2011-05-04 | 深圳市航嘉驰源电气股份有限公司 | Circuit for eliminating noise of switching power supply |
| CN102882365A (en) * | 2011-07-12 | 2013-01-16 | 南京博兰得电子科技有限公司 | Grounding method for adaptor power supply |
| CN103944353A (en) * | 2013-01-17 | 2014-07-23 | 常州隆辉照明科技有限公司 | High reliability bias power supply |
| CN105047385A (en) * | 2015-08-17 | 2015-11-11 | 江苏科谷电子有限公司 | High-frequency transformer and electronic magnetic interference (EMI) suppression circuit including same |
-
2016
- 2016-11-18 CN CN201611028062.9A patent/CN108075648B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010268623A (en) * | 2009-05-15 | 2010-11-25 | Hitachi Koki Co Ltd | Charger |
| CN201467002U (en) * | 2009-05-22 | 2010-05-12 | 王中美 | Power supply energy-saving circuit for household appliances and office equipment |
| CN102044961A (en) * | 2010-12-23 | 2011-05-04 | 深圳市航嘉驰源电气股份有限公司 | Circuit for eliminating noise of switching power supply |
| CN102882365A (en) * | 2011-07-12 | 2013-01-16 | 南京博兰得电子科技有限公司 | Grounding method for adaptor power supply |
| CN103944353A (en) * | 2013-01-17 | 2014-07-23 | 常州隆辉照明科技有限公司 | High reliability bias power supply |
| CN105047385A (en) * | 2015-08-17 | 2015-11-11 | 江苏科谷电子有限公司 | High-frequency transformer and electronic magnetic interference (EMI) suppression circuit including same |
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