CN109683107A - The EMI index adjusting, measuring method of Switching Power Supply - Google Patents

The EMI index adjusting, measuring method of Switching Power Supply Download PDF

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Publication number
CN109683107A
CN109683107A CN201811558179.7A CN201811558179A CN109683107A CN 109683107 A CN109683107 A CN 109683107A CN 201811558179 A CN201811558179 A CN 201811558179A CN 109683107 A CN109683107 A CN 109683107A
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China
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voltage
power supply
transformer
ground
switching power
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CN201811558179.7A
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CN109683107B (en
Inventor
赵双盟
叶利平
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SICHUAN CHANGHONG ELECTRONIC PARTS CO Ltd
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SICHUAN CHANGHONG ELECTRONIC PARTS CO Ltd
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/40Testing power supplies
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02MAPPARATUS 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
    • H02M1/00Details of apparatus for conversion
    • H02M1/44Circuits or arrangements for compensating for electromagnetic interference in converters or inverters

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Dc-Dc Converters (AREA)

Abstract

The present invention relates to testing fields, EMI test bring test complicated commissioning period long problem need to be carried out by large-scale regular laboratory for the EMI index of debugging Switching Power Supply, it is proposed a kind of EMI index adjusting, measuring method of Switching Power Supply, include: S1, when the anti-electromagnetic interference circuit of the primary side and primary side that there is connection transformer in measured switch power supply, removes the anti-electromagnetic interference circuit;The voltage on the primary ground of transformer and the voltage of secondary ground enter step S3, otherwise, the EMI index of representation switch power supply meets the requirements, and exits process if voltage difference between the two is greater than predetermined amplitude in S2, test Switching Power Supply;S3, according to the coil winding circle number of shield winding in the size relation adjustment transformer between the absolute value of the voltage of the absolute value and secondary ground of the voltage on primary ground, enter step S2.This method only needs the commissioning that switch power supply EMI index can be completed with the voltage of secondary ground primaryly of test transformer, the exploitation suitable for Switching Power Supply.

Description

The EMI index adjusting, measuring method of Switching Power Supply
Technical field
The present invention relates to testing field, in particular to the EMI index adjusting, measuring method of a kind of Switching Power Supply.
Background technique
Currently, various countries are all very stringent to the access control of Switching Power Supply (SMPS), environment friend of the people to electronic product Good property proposes increasingly higher demands, such as whether electromagnetic interference (EMI) index of electronic product meets the requirements and have become it Can the mandatory condition that sold on the market in the development process of Switching Power Supply, be substantially side to the EMI commissioning of Switching Power Supply Test side commissioning until EMI reaches requirement, and the test of EMI be typically necessary the large-scale regular laboratory of authorized by state into Row, testing expense is very high, and the period is also longer, and the experimental condition how to have by common laboratory refers to the EMI of Switching Power Supply Mark is estimated, it is necessary to explore a kind of simple reliable and stable method.
Summary of the invention
The technical problems to be solved by the present invention are: the EMI index for commissioning Switching Power Supply need to be by large-scale regular reality It tests room and carries out the problem that EMI test bring tests complicated commissioning period length, propose a kind of EMI index commissioning side of Switching Power Supply Method.
The present invention solves above-mentioned technical problem, the technical solution adopted is that:
The EMI index adjusting, measuring method of Switching Power Supply, includes the following steps:
S1, when in measured switch power supply connect transformer primary side and primary side anti-electromagnetic interference circuit in the presence of, Remove the anti-electromagnetic interference circuit;
The voltage of the voltage on the primary ground of transformer and secondary ground in S2, test measured switch power supply, if between the two Voltage difference is greater than predetermined amplitude, then enters step S3, otherwise, the EMI index of representation switch power supply meets the requirements, and exits process;
S3, it is adjusted and is become according to the size relation between the absolute value of the voltage of the absolute value and secondary ground of the voltage on primary ground Coil winding the number of turns of shield winding, enters step S2 in depressor.
Preferably, the anti-electromagnetic interference circuit includes capacitor.
Preferably, the step S2 includes the following steps:
S201, the primary ground that transformer in Switching Power Supply is connect using the anode of oscilloprobe, oscilloprobe The secondary ground of transformer in cathode connection switch voltage obtains the voltage on the primary ground of transformer and the voltage of secondary ground;
The voltage difference of the voltage of S202, the voltage for calculating primary ground and secondary ground, if the voltage difference is greater than predetermined amplitude, S3 is then entered step, otherwise, the EMI index of representation switch power supply meets the requirements, and exits process.
Preferably, the step S3 includes the following steps:
If the absolute value of the voltage on S301, primary ground is more than or equal to the absolute value of the voltage of secondary ground, enter step Otherwise S302 enters step S303;
S302, the coil winding the number of turns for increasing shield winding in transformer, enter step S2;
S303, the coil winding the number of turns for reducing shield winding in transformer, enter step S2.
Preferably, the predetermined amplitude is 2V.
The beneficial effects of the present invention are:
Switching Power Supply is judged by the size of the voltage difference between secondary ground primaryly of transformer in Switching Power Supply Whether EMI requirement is met, and the spill-out of transformer interference can propose the voltage between primary ground and secondary ground through the invention Difference characterizes, and the coil winding the number of turns for adjusting shield winding is the parasitic capacitance of the primary and secondary side for balancing transformer, make The interference obtained between parasitic capacitance offsets, and reaches and reduces the interference lock that inside transformer generates to the greatest extent change in inside transformer The spilling of depressor interference, when above-mentioned voltage difference is less than or equal to predetermined amplitude, the EMI index of representation switch power supply is conformed to It asks, this method only needs the commissioning that switch power supply EMI index can be completed with the voltage of secondary ground primaryly of test transformer, It avoids in background technique in order to which the EMI index of commissioning Switching Power Supply need to carry out Switching Power Supply by large-scale regular laboratory EMI tests bring and tests long problem of complicated commissioning period.
Detailed description of the invention
Fig. 1 is the flow chart of the EMI adjusting, measuring method of the embodiment of the present invention;
Fig. 2 is the circuit diagram of Switching Power Supply;
Wherein, R1 is resistance one, R2 is resistance two, R3 is resistance three, R4 is resistance four, R5 is resistance five, R6 is resistance Six, R7 is resistance seven, R8 is resistance eight, R9 is resistance nine, R10 is resistance ten, C1 is capacitor one, C2 is capacitor two, C3 is electricity Appearance three, C4 are capacitor four, C5 is capacitor five, C6 is capacitor six, C7 is capacitor seven, CY1 is Y capacitance, and D1 is diode one, D2 is Diode two, D3 are diode three, D4 is rectifier bridge, L1 is inductance one, PGND is primary ground, GND is secondary ground, L be firewire, N is zero curve, U1 is chip, T1 is transformer, N1 is armature winding, N2 is secondary windings, N3 is auxiliary winding, Vout+ is to open The anode that anode, the Vout- of the voltage output in powered-down source are the cathode of the voltage output of Switching Power Supply, V+ is rectifier bridge output, V- is the cathode of rectifier bridge output, A is input rectifying filter circuit, B is residual current absorbing circuit, C is pwm control circuit, D It is output rectifier and filter for transformer translation circuit, E, F is anti-electromagnetic interference circuit.
Specific embodiment
In order to make the objectives, technical solutions, and advantages of the present invention clearer, right with reference to the accompanying drawings and embodiments The present invention is further elaborated.
As shown in Figure 1, the EMI index adjusting, measuring method of Switching Power Supply, includes the following steps:
S1, when in measured switch power supply connect transformer primary side and primary side anti-electromagnetic interference circuit in the presence of, Remove the anti-electromagnetic interference circuit;The influence of anti-electromagnetic interference circuit can so be removed, if anti-electromagnetic interference circuit is not It removes, cannot be introduced into the test of step S2;
The voltage of the voltage on the primary ground of transformer and secondary ground in S2, test measured switch power supply, if between the two Voltage difference is greater than predetermined amplitude, then enters step S3, otherwise, the EMI index of representation switch power supply meets the requirements, and exits process;
S3, it is adjusted and is become according to the size relation between the absolute value of the voltage of the absolute value and secondary ground of the voltage on primary ground Coil winding the number of turns of shield winding, enters step S2 in depressor.
Wherein, one end of the shield winding in switching mode power supply transformer can connect primary ground, and the other end of shield winding can Vacantly;EMI index refers to the corresponding value of the electromagnetic interference of Switching Power Supply.
The high pressure and secondary ground of the armature winding of above-mentioned connection transformer, or, anti-electromagnetic interference circuit connection transformer Primary ground and secondary ground, or, after the high pressure of the armature winding of anti-electromagnetic interference circuit connection transformer and secondary windings rectification Output, or, the primary ground of anti-electromagnetic interference circuit connection transformer and the data after secondary windings rectification, wherein anti-electromagnetism is dry Disturbing circuit may include capacitor.
In order to simplify test equipment, oscillograph can be used and carry out the voltage tester with secondary ground primaryly, above-mentioned steps S2 May include following steps:
S201, the primary ground that transformer in Switching Power Supply is connect using the anode of oscilloprobe, oscilloprobe The secondary ground of transformer in cathode connection switch voltage obtains the voltage on the primary ground of transformer and the voltage of secondary ground;
The voltage difference of the voltage of S202, the voltage for calculating primary ground and secondary ground, if above-mentioned voltage difference is greater than predetermined amplitude, S3 is then entered step, otherwise, the EMI index of representation switch power supply meets the requirements, and exits process.
Coil winding the number of turns of shield winding specifically how is adjusted, above-mentioned steps S3 may include following steps:
If the absolute value of the voltage on S301, primary ground is more than or equal to the absolute value of the voltage of secondary ground, enter step Otherwise S302 enters step S303;
S302, the coil winding the number of turns for increasing shield winding in transformer, enter step S2;
S303, the coil winding the number of turns for reducing shield winding in transformer, enter step S2.
By the test of many times of a variety of Switching Power Supplies, 2V is set by above-mentioned predetermined amplitude, the EMI switched in this case Index is preferable, is able to satisfy the requirement of most of safety standards.
Embodiment
As shown in Fig. 2, the Switching Power Supply in the present embodiment includes absorbing electricity for input rectifying filter circuit A, residual current Road B, pwm control circuit C, transformer translation circuit D, output rectifier and filter E and anti-electromagnetic interference circuit F.
Input rectifying filter circuit A is used to AC process be direct current, in the present embodiment can be by 220V or 230V AC rectification be 310V or so direct current, specifically include: rectifier bridge D4, two C2 of one C1 of capacitor, one L1 of inductance and capacitor, Wherein, the input of rectifier bridge D4 connects alternating current, the anode and inductance one of positive one C1 of V+ connection capacitor of rectifier bridge D4 output One end of L1, the cathode of two C2 of one C1 of capacitor and capacitor connect primary ground, the anode of other end connection two C2 of capacitor of one L1 of inductance Anode output as input rectifying filter circuit A.
Residual current absorbing circuit B is used to absorb the leakage inductance spike of transformer, prevents chip U1 over-voltage breakdown, specific to wrap It includes: four C4 of capacitor, two D2 of seven R7 of resistance, eight R8 of resistance and diode, wherein one end of four C4 of capacitor connects current rectifying and wave filtering circuit The anode output of A and the non-same polarity of armature winding N1, the other end of four C4 of capacitor are sequentially connected in series seven R7 of resistance and diode two The cathode of D2, the Same Name of Ends of the anode connection armature winding N1 of diode two and the pin 7 and pin 8 of chip U1, eight R8 of resistance Then on capacitor C4 in parallel.
Pwm control circuit C is used to detect output voltage and the duty ratio by changing chip U1 output to control transformer Output voltage, specifically include: chip U1, one R1 of resistance, two R2 of resistance, three R3 of resistance, three C3 of capacitor, one D1 of diode, electricity Hinder six R6 of four R4, five R5 of resistance and resistance, wherein the anode output of one end connection input rectifying filter circuit A of one R1 of resistance, One end of two R2 of other end series resistor of one R1 of resistance, pin 1, three C3 of capacitor of the other end connection chip U1 of two R2 of resistance One end and resistance three R3 one end, the other end ground connection of three C3 of capacitor, other end connection one D1 of diode of three R3 of resistance Cathode, the Same Name of Ends of the anode connection auxiliary winding N3 of one D1 of diode and one end of resistance R4, the other end connection of resistance R4 One end of resistance R5 and the pin 2 of chip U1, the primary ground of other end connection of resistance R5, one end connection chip U1's of resistance R6 Pin 4, the pin 5 of chip U1 connects primary ground.
Transformer translation circuit D is used to pulse high-voltage being transformed to pulse low-voltage, specifically includes: transformer T1, Middle transformer T1 includes armature winding N1, secondary windings N2, auxiliary winding N3 and shield winding (being not shown in Fig. 2), shielding around The primary ground of one end connection of group, the other end of shield winding is hanging, the non-same polarity connection input rectifying filtering of armature winding N1 The anode output of circuit A, the anode of Same Name of Ends connection two D2 of diode of armature winding N1, the Same Name of Ends connection of auxiliary winding N3 The anode of one D1 of diode, the non-same polarity ground connection of auxiliary winding N3, the non-same polarity of secondary windings N2 connect secondary ground, it is secondary around Anode output of the Same Name of Ends of group N2 as transformer.
The pulse low-voltage that output rectifier and filter E is used to convert through transformer is processed into the low electricity of stable direct current Pressure, specifically includes: nine R9 of resistance, three D3 of diode, five C5 of capacitor, ten R10 of six C6 of capacitor, seven C7 of capacitor and resistance, wherein two Three D3 of pole pipe anode connection secondary windings N2 Same Name of Ends, three D3 of diode cathode connection, six C6 of capacitor anode, capacitor The anode of seven C7 and one end of ten R10 of resistance, and positive Vout of the one end of ten R10 of resistance as the voltage output of Switching Power Supply +, another termination secondary ground of the cathode of six C6 of capacitor, ten R10 of cathode and resistance of seven C7 of capacitor, the other end of ten R10 of resistance It is attempted by three D3 of diode after the cathode Vout- of voltage output as Switching Power Supply, nine R9 connection capacitor of resistance, five C5.
Anti- electromagnetic interference circuit F includes Y capacitance CY1, and wherein Y capacitance is call in row, and essence is exactly capacitor, Y capacitance The high pressure of one end connection armature winding of CY1, the other end of Y capacitance connect secondary ground.
Shield winding is initially set to 10 circle of enameled wire coiling of 0.19mm in above-mentioned switch transformer, that is to say, that shielding Coil winding the number of turns of winding is 10Ts, carries out whether test EMI meets the requirements with the following method:
Step 1: needing to connect transformer in removal Switching Power Supply first there are anti-electromagnetic interference circuit in the present embodiment Armature winding high pressure and secondary ground between anti-electromagnetic interference circuit, that is, the present embodiment in Y capacitance CY1;
Step 2: the anode of oscilloprobe connects the primary ground of transformer in Switching Power Supply, the cathode of oscilloprobe is connect The secondary ground of transformer in switching voltage.The voltage that test obtains the primary ground of transformer is 6.240V, obtains time of transformer Voltage between grade ground is 160.0mv, and voltage difference between the two is that 6.08V is greater than scheduled assignment 2V, represents EMI and does not meet It is required that;
The above-mentioned complete Switching Power Supply via line impedance stable network (LISN) for not removing anti-electromagnetic interference circuit is set Standby connection EMI special test equipment spectrum analyzer carries out traditional laboratory EMI test, and test obtains (the quasi- peak of EMI QP Value) it meets the requirements, AV (average value of EMI) is undesirable, and the standard that EMI conduction test passes through is that QP and AV is intended to meet It is required that is, final result is that EMI index is undesirable consistent with the result of the qualitative test of step two of the invention.
Step 3: then needing to increase shielding because the absolute value of the voltage on primary ground is greater than the absolute value between secondary ground The number of turns of winding, it is 15 circles that coil winding the number of turns of shield winding is increased by 10 circles, uses the anode of oscilloprobe again The primary ground of transformer in Switching Power Supply is connect, the cathode of oscilloprobe connects the secondary ground of transformer in switching voltage, tests Voltage to the primary ground of transformer is 80mV, and obtaining the voltage between the secondary ground of transformer is -5.36v, between the two Voltage difference is that 5.44V is greater than scheduled assignment 2V, and it is undesirable to represent EMI;
Do not remove after above-mentioned complete Switching Power Supply shield winding is modified by step 3 and anti-electromagnetic interference circuit as Laboratory EMI test object, Switching Power Supply via line impedance stable network (LISN) equipment connect EMI special test equipment frequency spectrum Analyzer carries out traditional laboratory EMI test, and test show that QP (quasi-peak value of EMI) meets the requirements, AV (average value of EMI) It is undesirable, and the standard that EMI conduction test passes through is that QP and AV is intended to meet the requirements, that is, final result is that EMI refers to Mark undesirable, this is consistent with the result of the qualitative test of step three of the invention.
Step 4: then needing to reduce shielding because the absolute value of the voltage on primary ground is less than the absolute value between secondary ground The number of turns of winding, it is 13 circles that coil winding the number of turns of shield winding is increased by 15 circles, uses the anode of oscilloprobe again The primary ground of transformer in Switching Power Supply is connect, the cathode of oscilloprobe connects the secondary ground of transformer in switching voltage, tests Voltage to the primary ground of transformer is 2.24V, and obtaining the voltage between the secondary ground of transformer is 1.36v, between the two Voltage difference is that 880mV is less than in scheduled assignment 2V, represents EMI and meets the requirements;
Do not remove after above-mentioned complete Switching Power Supply shield winding is modified by step 3 and anti-electromagnetic interference circuit as Laboratory EMI test object, Switching Power Supply via line impedance stable network (LISN) equipment connect EMI special test equipment frequency spectrum point Analyzer carries out traditional laboratory EMI test, and test show that QP (quasi-peak value of EMI) meets the requirements, and AV (average value of EMI) meets It is required that is, final result is that EMI index meets the requirements, this is consistent with the result of the qualitative test of step four of the invention.

Claims (5)

1. the EMI index adjusting, measuring method of Switching Power Supply, which comprises the steps of:
S1, when in measured switch power supply connect transformer primary side and primary side anti-electromagnetic interference circuit in the presence of, remove The anti-electromagnetic interference circuit;
The voltage of the voltage on the primary ground of transformer and secondary ground in S2, test measured switch power supply, if voltage between the two Difference is greater than predetermined amplitude, then enters step S3, otherwise, the EMI index of representation switch power supply meets the requirements, and exits process;
S3, transformer is adjusted according to the size relation between the absolute value of the voltage of the absolute value and secondary ground of the voltage on primary ground Coil winding the number of turns of middle shield winding, enters step S2.
2. the EMI index adjusting, measuring method of Switching Power Supply as described in claim 1, which is characterized in that the anti-electromagnetic interference electricity Road includes capacitor.
3. the EMI index adjusting, measuring method of Switching Power Supply as described in claim 1, which is characterized in that the step S2 includes such as Lower step:
S201, the primary ground that transformer in Switching Power Supply is connect using the anode of oscilloprobe, the cathode of oscilloprobe The secondary ground of transformer in connection switch voltage obtains the voltage on the primary ground of transformer and the voltage of secondary ground;
The voltage difference of the voltage of S202, the voltage for calculating primary ground and secondary ground, if the voltage difference is greater than predetermined amplitude, into Enter step S3, otherwise, the EMI index of representation switch power supply meets the requirements, and exits process.
4. the EMI index adjusting, measuring method of Switching Power Supply as described in claim 1, which is characterized in that the step S3 includes such as Lower step:
If the absolute value of the voltage on S301, primary ground is more than or equal to the absolute value of the voltage of secondary ground, S302 is entered step, it is no Then, S303 is entered step;
S302, the coil winding the number of turns for increasing shield winding in transformer, enter step S2;
S303, the coil winding the number of turns for reducing shield winding in transformer, enter step S2.
5. the EMI index adjusting, measuring method of Switching Power Supply as claimed in claim 1 or 2 or 3 or 4, which is characterized in that described predetermined Amplitude is 2V.
CN201811558179.7A 2018-12-19 2018-12-19 EMI index adjusting and measuring method of switching power supply Active CN109683107B (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111740615A (en) * 2020-06-13 2020-10-02 深圳市海洋王照明工程有限公司 Temperature and humidity detection device and switching power supply circuit thereof
EP3982526A4 (en) * 2019-06-20 2023-07-12 Sanden Corporation Switched-mode power supply device and vehicle-mounted electric compressor equipped with same, and method for manufacturing switched-mode power supply device
CN116718862A (en) * 2023-08-07 2023-09-08 杭州得明电子有限公司 Shielding effect detection method for flyback transformer shielding layer

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102231318A (en) * 2011-04-11 2011-11-02 上海新进半导体制造有限公司 Method and transformer for reducing common-mode interference in sandwich winding transformer
US20140375352A1 (en) * 2011-09-15 2014-12-25 University Of Washington Through Its Center For Commercialization Systems and methods for sensing environmental changes using light sources as sensors
CN107479006A (en) * 2017-07-27 2017-12-15 深圳Tcl新技术有限公司 The power supply EMI rejection abilities assessment system and method for a kind of electronic equipment
CN108872880A (en) * 2018-05-29 2018-11-23 珠海格力电器股份有限公司 Switching power supply EMI testing device and method

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102231318A (en) * 2011-04-11 2011-11-02 上海新进半导体制造有限公司 Method and transformer for reducing common-mode interference in sandwich winding transformer
US20140375352A1 (en) * 2011-09-15 2014-12-25 University Of Washington Through Its Center For Commercialization Systems and methods for sensing environmental changes using light sources as sensors
CN107479006A (en) * 2017-07-27 2017-12-15 深圳Tcl新技术有限公司 The power supply EMI rejection abilities assessment system and method for a kind of electronic equipment
CN108872880A (en) * 2018-05-29 2018-11-23 珠海格力电器股份有限公司 Switching power supply EMI testing device and method

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3982526A4 (en) * 2019-06-20 2023-07-12 Sanden Corporation Switched-mode power supply device and vehicle-mounted electric compressor equipped with same, and method for manufacturing switched-mode power supply device
CN111740615A (en) * 2020-06-13 2020-10-02 深圳市海洋王照明工程有限公司 Temperature and humidity detection device and switching power supply circuit thereof
CN116718862A (en) * 2023-08-07 2023-09-08 杭州得明电子有限公司 Shielding effect detection method for flyback transformer shielding layer
CN116718862B (en) * 2023-08-07 2023-10-27 杭州得明电子有限公司 Shielding effect detection method for flyback transformer shielding layer

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