CN112019039A - Power interface circuit with high-grade surge protection and high EMI performance - Google Patents
Power interface circuit with high-grade surge protection and high EMI performance Download PDFInfo
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- CN112019039A CN112019039A CN202010883848.9A CN202010883848A CN112019039A CN 112019039 A CN112019039 A CN 112019039A CN 202010883848 A CN202010883848 A CN 202010883848A CN 112019039 A CN112019039 A CN 112019039A
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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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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
- H02H9/04—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage
- H02H9/041—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage using a short-circuiting device
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
- H02H9/04—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage
- H02H9/06—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage using spark-gap arresters
-
- 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
- H02M1/12—Arrangements for reducing harmonics from AC input or output
- H02M1/126—Arrangements for reducing harmonics from AC input or output using passive filters
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Emergency Protection Circuit Devices (AREA)
- Filters And Equalizers (AREA)
Abstract
The invention relates to a high-level surge protection high EMI performance power interface circuit, wherein the input end of the circuit is connected with a power supply, and the output end of the circuit is connected with a load; the protection circuit module comprises a first piezoresistor, a second piezoresistor, a third piezoresistor and a gas discharge tube; the first filter circuit module comprises more than one first-stage filter circuit, and the first-stage filter circuit comprises a first-stage differential mode filter capacitor, a first-stage first common mode filter capacitor, a first-stage second common mode filter capacitor and a common mode filter inductor; the second filter circuit module comprises a second-stage filter circuit, wherein the second-stage filter circuit comprises a first differential mode filter inductor, a second differential mode filter capacitor, a second-stage first common mode filter capacitor and a second-stage second common mode filter capacitor. The invention has three functions of electromagnetic safety, surge protection, electromagnetic interference resistance and the like, and has common-mode protection and differential-mode protection in the aspect of surge protection design.
Description
Technical Field
The invention relates to the technical field of circuit design, in particular to a high-level surge protection high-EMI performance power interface circuit.
Background
The alternating current power supply interface is connected with a power grid through a power line and provides electric energy for the electrical equipment. During operation, electrical products generate various interferences, such as interferences generated by power conversion circuits, high-frequency transformers, digital circuits and the like, which form conducted interference on a power grid and radiated interference on a space through a power interface.
When a high-power inductive load is switched on or off on a power grid or the power grid is struck by lightning, transient pulse interference and surge interference can be generated at a power interface, if the power interface is not subjected to protection filtering design, the interference can easily influence the normal work of equipment, and the lightning interference can even damage the equipment, so that the alternating current power interface needs to be subjected to electromagnetic compatibility design, the stable work of the equipment is ensured, and the traditional alternating current power interface cannot meet the requirement of increasingly severe electromagnetic environment adaptability.
Disclosure of Invention
The invention provides a high-level surge protection and high EMI performance power interface circuit, which is designed for relevant interference suppression and sensitivity resistance on the basis of an EMC principle and is compatible with an interface lightning protection design.
In order to achieve the above object, an embodiment of the present invention provides a high-level surge protection high EMI performance power interface circuit, an input end of which is connected to a power supply and an output end of which is connected to a load, and the high-level surge protection high EMI performance power interface circuit is characterized by comprising a protection circuit module, a first filter circuit module and a second filter circuit module which are electrically connected in sequence; wherein,
the protection circuit module comprises a first piezoresistor playing a role in differential mode protection, a second piezoresistor, a third piezoresistor and a gas discharge tube playing a role in common mode protection;
the first filter circuit module comprises more than one first-stage filter circuit, and the first-stage filter circuit comprises a first-stage differential mode filter capacitor for inhibiting differential mode interference on a line, a first-stage first common mode filter capacitor for providing a low-impedance loop for common mode interference, a first-stage second common mode filter capacitor and a common mode filter inductor for inhibiting common mode interference on the line;
the second filter circuit module comprises a second-stage filter circuit, wherein the second-stage filter circuit comprises a first differential mode filter inductor and a second differential mode filter inductor which are used for filtering alternating current on the circuit, a second differential mode filter capacitor which is used for inhibiting differential mode interference on the circuit, and a second-stage first common mode filter capacitor and a second-stage second common mode filter capacitor which are used for providing a low-impedance loop for common mode interference.
Preferably, in the protection circuit module, the first piezoresistor is connected in parallel with a second piezoresistor and a third piezoresistor which are connected in series, one end of the second piezoresistor is connected with a live wire, one end of the third piezoresistor is connected with a zero wire, the other ends of the second piezoresistor and the third piezoresistor are connected in a collinear manner with one end of the gas discharge tube, and the other end of the gas discharge tube is connected with a ground wire.
As a preferred scheme, in the first filter circuit module, two ends of the first-stage differential-mode filter capacitor are respectively connected to a live wire and a null wire, one end of the first-stage first common-mode filter capacitor is connected to the live wire, one end of the first-stage second common-mode filter capacitor is connected to the null wire, the other ends of the first-stage first common-mode filter capacitor and the first-stage second common-mode filter capacitor are connected to a ground wire in a collinear manner, two ends of the common-mode filter inductor are respectively connected to the live wire and the null wire, and the first-stage first common-mode filter capacitor and the first-stage second common-mode filter capacitor are located between the first-.
Preferably, components in the interface circuit are arranged according to a signal flow direction, and a principle of protection before filtering is followed.
As a preferred scheme, the differential mode capacitor in the interface circuit selects an X capacitor with a rated voltage of more than 250V, and the common mode capacitor selects a Y capacitor with a rated voltage of 250V.
Preferably, the interface position of the interface circuit needs to be added with a fuse.
Compared with the prior art, the embodiment of the invention has the beneficial effects that: the circuit is provided with the primary filter circuit, the secondary filter circuit and the tertiary filter circuit simultaneously, and has three functions of electromagnetic safety, surge protection, anti-electromagnetic interference and the like, in the aspect of surge protection design, the common-mode protection and the differential-mode protection are provided, and compared with a commonly adopted TVS circuit, the piezoresistor and the gas discharge tube have higher through-current capacity and have the advantage of low price. In the aspect of EMI resistance design, only one stage of filter circuit is generally designed, the invention can effectively meet the requirements of high-level surge protection, high EMI performance and safety of an AC power supply, and can delete the stage number of the filter circuit according to the subsequent actual test condition when the EMI test allowance is higher, thereby having higher flexibility.
Drawings
In order to more clearly illustrate the technical solution of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.
Fig. 1 is a circuit diagram of a power interface with high EMI performance for high-level surge protection according to an embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1, the high-level surge protection high EMI performance power interface circuit provided in the embodiment of the present invention has an input terminal connected to a power supply and an output terminal connected to a load, and includes a protection circuit module 1, a first filter circuit module 2, and a second filter circuit module 3, which are electrically connected in sequence; wherein,
the protection circuit module 1 comprises a first piezoresistor RV1 playing a role in differential mode protection, a second piezoresistor RV2 playing a role in common mode protection, a third piezoresistor RV3 and a gas discharge tube GDT 1;
the first filter circuit module 2 includes more than one first-stage filter circuit, in this embodiment, two first-stage filter circuits are provided, which are a first-stage filter circuit 201 and a second first-stage filter circuit 202;
the first primary filter circuit 201 includes a differential mode filter capacitor C1 for suppressing differential mode interference on the line, a first common mode filter capacitor C2 and a second common mode filter capacitor C3 for providing a low impedance loop for common mode interference, and a common mode filter inductor L1 for suppressing common mode interference on the line;
the second primary filter circuit 202 includes a differential mode filter capacitor C4 for suppressing differential mode interference on the line, a common mode filter capacitor C5 and a common mode filter capacitor C6 for providing a low impedance loop for common mode interference, and a common mode filter inductor L2 for suppressing common mode interference on the line;
the second filter circuit module 3 includes a second-stage filter circuit, and the second-stage filter circuit includes a first differential-mode filter inductor L3 and a second differential-mode filter inductor L4 for filtering the alternating current on the circuit, a second-stage differential-mode filter capacitor C7 for suppressing the differential-mode interference on the circuit, and a second-stage first common-mode filter capacitor C8 and a second-stage second common-mode filter capacitor C9 for providing a low-impedance loop for the common-mode interference.
Preferably, in the protection circuit module, the first piezoresistor is connected in parallel with a second piezoresistor and a third piezoresistor which are connected in series, one end of the second piezoresistor is connected with a live wire, one end of the third piezoresistor is connected with a zero wire, the other ends of the second piezoresistor and the third piezoresistor are connected in a collinear manner with one end of the gas discharge tube, and the other end of the gas discharge tube is connected with a ground wire.
As a preferred scheme, in the first filter circuit module, two ends of the first-stage differential-mode filter capacitor are respectively connected to a live wire and a null wire, one end of the first-stage first common-mode filter capacitor is connected to the live wire, one end of the first-stage second common-mode filter capacitor is connected to the null wire, the other ends of the first-stage first common-mode filter capacitor and the first-stage second common-mode filter capacitor are connected to a ground wire in a collinear manner, two ends of the common-mode filter inductor are respectively connected to the live wire and the null wire, and the first-stage first common-mode filter capacitor and the first-stage second common-mode filter capacitor are located between the first-.
Preferably, components in the interface circuit are arranged according to a signal flow direction, and a principle of protection before filtering is followed.
Preferably, the differential mode capacitor in the interface circuit is an X capacitor (capacitor for suppressing power supply electromagnetic interference) with a rated voltage of more than 250V, and the common mode capacitor is a Y capacitor with a rated voltage of 250V. The X capacitor and the Y capacitor are safety capacitors and are used for filtering in an anti-interference circuit. The X capacitor and the Y capacitor are used in a power supply filter, play a role in power supply filtering and respectively play a role in filtering common mode interference and differential mode interference. The normal capacitor retains charge for a long time after the external power source is disconnected, and is electrically reached if touched by hand, while the safety capacitor does not have this problem. The X capacitance is a capacitance connected between two lines (L-N) of the power line, and the Y capacitance is a capacitance connected between two lines (L-E, N-E) of the power line and the ground respectively. The value of the Y capacitance cannot be too large based on the limitation of the leakage current, and typically the X capacitance is of the uF class and the Y capacitance is of the nF class. The X capacitor suppresses differential mode interference, and the Y capacitor suppresses common mode interference.
Preferably, the interface position of the interface circuit needs to be added with a fuse because the piezoresistor failure mode is a short circuit, which may cause a large current.
The circuit has strong comprehensiveness, and meets the requirements of high-level surge protection, high EMI performance and safety. The circuit protection capability of the equipment of the circuit in the actual test can reach the following indexes:
while the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention.
Claims (6)
1. A high-grade surge protection high EMI performance power interface circuit is characterized by comprising a protection circuit module, a first filter circuit module and a second filter circuit module which are electrically connected in sequence, wherein the input end of the protection circuit module is connected with a power supply, and the output end of the protection circuit module is connected with a load; wherein,
the protection circuit module comprises a first piezoresistor playing a role in differential mode protection, a second piezoresistor, a third piezoresistor and a gas discharge tube playing a role in common mode protection;
the first filter circuit module comprises more than one first-stage filter circuit, and the first-stage filter circuit comprises a first-stage differential mode filter capacitor for inhibiting differential mode interference on a line, a first-stage first common mode filter capacitor for providing a low-impedance loop for common mode interference, a first-stage second common mode filter capacitor and a common mode filter inductor for inhibiting common mode interference on the line;
the second filter circuit module comprises a second-stage filter circuit, wherein the second-stage filter circuit comprises a first differential mode filter inductor and a second differential mode filter inductor which are used for filtering alternating current on the circuit, a second differential mode filter capacitor which is used for inhibiting differential mode interference on the circuit, and a second-stage first common mode filter capacitor and a second-stage second common mode filter capacitor which are used for providing a low-impedance loop for common mode interference.
2. The high-level surge-protection and high-EMI performance power interface circuit according to claim 1, wherein in the protection circuit module, the first voltage dependent resistor is connected in parallel with a second voltage dependent resistor and a third voltage dependent resistor which are connected in series, one end of the second voltage dependent resistor is connected to a live wire, one end of the third voltage dependent resistor is connected to a neutral wire, the other ends of the second voltage dependent resistor and the third voltage dependent resistor are connected in a collinear manner to one end of the gas discharge tube, and the other end of the gas discharge tube is connected to a ground wire.
3. The high-level surge-protection high-EMI performance power interface circuit according to claim 1, wherein in the first filter circuit module, two ends of the first-level differential-mode filter capacitor are respectively connected to a live line and a neutral line, one end of the first-level first common-mode filter capacitor is connected to the live line, one end of the first-level second common-mode filter capacitor is connected to the neutral line, the other ends of the first-level first common-mode filter capacitor and the first-level second common-mode filter capacitor are connected to a ground line in a collinear manner, two ends of the common-mode filter inductor are respectively connected to the live line and the neutral line, and the first-level first common-mode filter capacitor and the first-level second common-mode filter capacitor are located between the first-level differential-.
4. The high-level surge-protection and high-EMI performance power interface circuit as recited in claim 1, wherein components in said interface circuit are laid out according to signal flow direction, following a protection-first followed by filtering principle.
5. The high-level surge-protection and high-EMI performance power interface circuit of claim 1, wherein the differential-mode capacitor in the interface circuit is an X capacitor with a voltage rating of 250V or more, and the common-mode capacitor is a Y capacitor with a voltage rating of 250V.
6. A high level surge protection and high EMI performance power interface circuit as recited in claim 1, wherein said interface location of said interface circuit requires the addition of a fuse.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010883848.9A CN112019039A (en) | 2020-08-28 | 2020-08-28 | Power interface circuit with high-grade surge protection and high EMI performance |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010883848.9A CN112019039A (en) | 2020-08-28 | 2020-08-28 | Power interface circuit with high-grade surge protection and high EMI performance |
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| CN112019039A true CN112019039A (en) | 2020-12-01 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202010883848.9A Pending CN112019039A (en) | 2020-08-28 | 2020-08-28 | Power interface circuit with high-grade surge protection and high EMI performance |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112865057A (en) * | 2021-03-19 | 2021-05-28 | 厦门赛尔特电子有限公司 | Electromagnetic protection circuit |
| CN113315366A (en) * | 2021-05-13 | 2021-08-27 | 珠海格力电器股份有限公司 | Filtering device, electrical equipment and filtering method thereof |
| CN113824298A (en) * | 2021-08-27 | 2021-12-21 | 广西电网有限责任公司电力科学研究院 | Power frequency power supply filter circuit |
| CN113872433A (en) * | 2021-10-15 | 2021-12-31 | 青岛鼎信通讯股份有限公司 | Topology for improving anti-surge capacity of LCL type grid-connected inverter |
| CN113964832A (en) * | 2021-11-01 | 2022-01-21 | 青岛鼎信通讯股份有限公司 | Topology for reducing influence of power quality equipment on carrier meter reading |
| CN114567154A (en) * | 2022-01-24 | 2022-05-31 | 中国电子科技集团公司第十八研究所 | Power filter with surge current suppression function |
| WO2022166390A1 (en) * | 2021-02-05 | 2022-08-11 | 中兴通讯股份有限公司 | Filter circuit, protection device and electrical device |
| WO2022199683A1 (en) * | 2021-03-26 | 2022-09-29 | 长春捷翼汽车零部件有限公司 | Charging device interface circuit and charging device |
| WO2023273294A1 (en) * | 2021-06-29 | 2023-01-05 | 杭州米福科技有限公司 | Front-end auxiliary circuit of high-power capacitive load instrument |
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| CN114567154A (en) * | 2022-01-24 | 2022-05-31 | 中国电子科技集团公司第十八研究所 | Power filter with surge current suppression function |
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Application publication date: 20201201 |