CN208316588U - A kind of Width funtion adds the Switching Power Supply of surge voltage protection - Google Patents

Abstract

The utility model belongs to Switching Power Supply protection technique field, it is related to the Switching Power Supply that a kind of Width funtion adds surge voltage protection, main structure includes varistor module, three side pressure heat-sensitive modules, metal-oxide-semiconductor decompression and TVS pipe voltage-limiting protection module and switch power module, it further include power supply, HVCC, PGND, inductance coil LN5, the conventional electrical component in the circuit RCD and switching power circuit, use input voltage for the power supply of 80Vac-500Vac, generated peak voltage between control chip UN1 switch is absorbed using the circuit RCD, first order protection is carried out to switching power circuit using varistor module, second level protection is carried out to switching power circuit using three side pressure heat-sensitive modules, keep surge voltage phase voltage clamped in 390V, using metal-oxide-semiconductor decompression and TV S pipe voltage-limiting protection module carries out third level protection to switching power circuit, so that the voltage clamping between the capacitor EN1 and capacitor EN2 of the rear end switching tube QN1 carries out fourth stage protection to switching power circuit to 650V, using switch power module.

Description

A kind of Width funtion adds the Switching Power Supply of surge voltage protection

Technical field:

The utility model belongs to Switching Power Supply protection technique field, is related to the switch that a kind of Width funtion adds surge voltage protection Power supply, the Switching Power Supply scheme for wide input high reliability provide a kind of novel thinking, are suitable for platform area input voltage Excessively high three-phase meter and terminal scheme.

Background technique:

Traditional three-phase meter and terminal scheme is applied when high voltage input table area is using Switching Power Supply scheme, due to platform area Voltage is high and power network fluctuation and Switching Power Supply can be made to occur damaging or high-voltage capacitance bulge in high temperature hostile and lightning stroke The case where bursting, therefore common solution has: the 1. high-voltage capacitance concatenated modes high using multiple pressure voltages, such as: in A kind of more capacitor series average-voltage circuits disclosed in state's patent 201720752140.3 include 2 capacitor series average-voltage circuits, resistance R7, resistance R8, resistance R9, NPN triode Q5, PNP triode Q6；The one end the resistance R9 respectively with 2 capacitor series average-voltages Circuit electrical connection, the resistance R9 other end are electrically connected with the emitter of the emitter of NPN triode Q5 and PNP triode Q6 respectively； The one end resistance R7 is connect with the base stage of the one end resistance R8, the base stage of NPN triode Q5 and PNP triode Q6 respectively, and resistance R7 is another One end is electrically connected with the collector of NPN triode Q5, DC bus anode and a capacitor series average-voltage circuit respectively；Resistance R8 The other end is electrically connected with the collector of NPN triode Q6, DC bus cathode and another capacitor series average-voltage circuit respectively；In A kind of metalized multi-stage serial supervoltage capacitor disclosed in state's patent 201020259670.2 includes thin film dielectric layer, is vaporized on The metallization coating used on thin film dielectric layer as electrode, the metallization coating be in discontinuous multi-segment structure, section with It is blank isolation strip between section, setting thickeies coating on each section of metallization coating respectively, and the thickening coating respectively corresponds The blank isolation strip position of grade or junior；A kind of farad capacitor plural serial stage voltage disclosed in Chinese patent 200720030861.X Equalizing circuit include farad capacitor and, it is silicon-controlled and, current-limiting resistance and, it is characterised in that the anode of farad capacitor connects 5V voltage, The cathode of farad capacitor connects the anode of farad capacitor, the cathode ground connection of farad capacitor, and the anode of farad capacitor connects silicon-controlled yin Pole, silicon-controlled control electrode and the short circuit of silicon-controlled cathode；Silicon-controlled anode connects current-limiting resistance, and current-limiting resistance connects farad capacitor Cathode and silicon-controlled cathode, silicon-controlled control electrode and the short circuit of silicon-controlled cathode, silicon-controlled anode connect current-limiting resistance, The other end of current-limiting resistance is grounded；It is a kind of disclosed in Chinese patent 200880115065.3 to be formed as single electrolytic cell structure Electrochemical double layer capacitor series stack.Cascade multi-electrode stack of components has the electrode assembly of series connection electrical connection, described Electrode assembly has the double-sided activated-carbon electrode formed on a current collector, and Power tabs are connected to the electrode assembly of end, also mention It is supplied with electric power and solves matter, polymer pouches accommodate the electrolyte and electrode assembly, electrode assembly form two-sided activated carbon on a current collector Electrode, the EDLC stack the multiple massless regions for having multiple sections and separating the multiple section, and described section is to fold, and make Obtain the vertex that massless region is arranged on each fold；This mode reliability is low, to high-voltage capacitance and rear end MOS and control The requirement of coremaking piece is relatively high；2. using reducing protective circuit (Anti-surging decompression), the reliability of power supply, existing skill can be improved Scheme in art using the Switching Power Supply for inhibiting surge voltage protection is less, using the scheme of wide-voltage range input switch power supply It is more, such as: disclosed in Chinese patent 201510115200.6 it is a kind of suitable for wide-voltage range input high efficiency keep apart Powered-down source includes high-frequency isolation converter and converter logic control circuit, the high-frequency isolation transformer include two former ends around Group n1 and n2, a pair end winding n3 and six switching tube Q1~Q6；The source electrode of Q1 connects the of the same name of the first original end winding n1 End, one end of the drain electrode connection input voltage of Q1；The Same Name of Ends of the first original end winding n1 of drain electrode connection of Q2, the source electrode connection of Q2 The other end of input voltage；The source electrode of Q3 connects the Same Name of Ends of the second original end winding n2, the drain electrode of the drain electrode connection Q1 of Q3；Q4's The Same Name of Ends of the second original end winding n2 of drain electrode connection, the source electrode of the source electrode connection Q2 of Q4；The second former end of source electrode connection winding of Q5 The different name end of n2, the drain electrode of the drain electrode connection Q1 of Q5；The different name end of the second original end winding n2 of drain electrode connection of Q6, the source electrode of Q6 connect Connect the source electrode of Q2；First original end winding n1 and the second original end winding n2 connects capacitance CR1 and CR2 respectively, wherein CR1's One end connects the different name end of n1, and the other end connects the Same Name of Ends of n2, the different name end of one end connection n2 of CR2, and the other end connects Q6 Drain electrode；Change the former end equivalent winding of converter by the on-off of converter logic control circuit control switch pipe to realize Efficiency operation of the Switching Power Supply in entire wide range input voltage, specifically: when input voltage is lower, switching tube In common full-bridge mode state, switching tube Q5 and Q6, which are in, continues off state for Q1-Q4 work, and the equivalent former end winding of converter is N1, converter boost is relatively high at this time；When input voltage increases, switching tube Q1, Q2, Q5 and Q6 work in common full-bridge mode State, switching tube Q3 and Q4, which are in, continues off state, and the equivalent former end winding of converter is n1+n2, at this time converter boost ratio It decreases compared with premode；When input voltage continues to increase, converter enters half-bridge working condition, at this time switching tube Q1 and Q2 Work is in half-bridge mode, and switching tube Q3, Q4 and Q5 shutdown, switching tube Q6 constant conduction, the equivalent former end winding of converter is n1+ n2；A kind of distribution terminal Width funtion input switch power supply disclosed in Chinese patent 201420107710.X, including rectifying and wave-filtering electricity Road, the current rectifying and wave filtering circuit output are connected with high frequency transformer and auxiliary switch circuit, the high frequency transformer and direct current Output circuit is connected with overvoltage crowbar, the auxiliary switch circuit and the high frequency transformer and control switch pipe circuit It is connected, the control switch pipe circuit is connected with the high frequency transformer and PWM switch controller, the PWM switch controller It is connected with feed circuit, the feed circuit is connected with the DC output circuit；201320338560.9 disclosure of Chinese patent A kind of efficient low-power consumption wide-voltage switch power supply, including sequentially connected input power, EMI protection circuit, rectifying and wave-filtering electricity Road, switch transformer module and output filter circuit are additionally provided with Anti-surging guarantor between the input power and EMI protection circuit Protection circuit, the anti-surge protection circuit are thermistor；A kind of Width funtion model disclosed in Chinese patent 201520286638.6 The Switching Power Supply enclosed includes Switching Power Supply DC, rectification circuit, bleeder circuit, current-limiting circuit and driving circuit, and the of rectification circuit The connection of the zero line of one current input terminal and external ac power source, the second current input terminal and external ac power source of rectification circuit Zero line side connection, the first current output terminal of rectification circuit the first current input terminal with bleeder circuit and driving circuit respectively Connection, the second current output terminal of rectification circuit is connect with the second current input terminal of bleeder circuit and driving circuit respectively, whole First current output terminal of current circuit is connect with one end of Switching Power Supply DC, the current output terminal and Switching Power Supply DC of driving circuit Other end connection, the current input terminal of the current output terminal of bleeder circuit and current-limiting circuit connects, and the electric current of current-limiting circuit is defeated The connection of the third current input terminal of outlet and driving circuit；A kind of super wide voltage disclosed in Chinese patent 201610048417.4 is defeated The Unisolated switch power circuit entered, including input terminal and output end, further include current rectifying and wave filtering circuit, metal-oxide-semiconductor bleeder circuit, Buck reduction voltage circuit and voltage-stabilizing output circuit, the input terminal current rectifying and wave filtering circuit, metal-oxide-semiconductor bleeder circuit, buck decompression electricity Road, voltage-stabilizing output circuit and output end are sequentially connected；The metal-oxide-semiconductor bleeder circuit includes MOSFET, second resistance, the first electricity Resistance, the first voltage-stabiliser tube and the 4th voltage-stabiliser tube, the pole D of the MOSFET are connect with current rectifying and wave filtering circuit, one end of second resistance and The pole D of the MOSFET connects, and the other end is connect with the pole G of the MOSFET；The pole S of the anode and MOSFET of 4th voltage-stabiliser tube It is connected, the connection of the pole G of one end and the MOSFET of cathode and first resistor, the other end of first resistor and the first voltage-stabiliser tube Cathode is connected, and the anode of the first voltage-stabiliser tube is connect with buck reduction voltage circuit；One kind disclosed in Chinese patent 201620280984.8 The circuit topological structure of efficient isolated multipath Width funtion output switch power source includes push-pull circuit, current rectifying and wave filtering circuit, synchronization Rectification BUCK circuit and circuit of reversed excitation, the input terminal of the push-pull circuit are connected with power supply, output end and current rectifying and wave filtering circuit Input terminal be connected, the output of current rectifying and wave filtering circuit is connected with synchronous rectification BUCK circuit, circuit of reversed excitation respectively, it is described synchronize it is whole The output end for flowing BUCK circuit is power supply low-voltage output, and the output end of the circuit of reversed excitation is power supply high-voltage output end；China A kind of Switching Power Supply topological circuit of the input of Width funtion disclosed in patent 201620909244.6 includes EMI circuit, input rectifying The input terminal of circuit, voltage comparator circuit, Boost circuit, full-bridge circuit and output rectification circuit, rectification circuit passes through EMI circuit is electrically connected with AC input lines road, and voltage comparison module is made of voltage comparator circuit and relay, the voltage ratio It is electrically connected compared with circuit with the output end of rectification circuit, the input terminal of the relay is electrically connected with rectification circuit, and voltage compares Circuit control relay closure is opened, and Boost circuit is electrically connected with an output end of relay, exports rectified current Road is electrically connected with an output end of full-bridge converter；A kind of output of Width funtion disclosed in Chinese patent 201621480332.5 Switching power circuit includes the high frequency transformer equipped with output winding and auxiliary winding, is connected to output on the output winding Current rectifying and wave filtering circuit is connected with auxiliary end current rectifying and wave filtering circuit, the anode connection of the auxiliary winding in the auxiliary winding In the power pins of chip, including voltage regulator circuit, the voltage regulator circuit is connected to auxiliary end current rectifying and wave filtering circuit and chip Between power pins, the voltage regulator circuit includes triode, resistance and zener diode, the collector and auxiliary of the triode End current rectifying and wave filtering circuit mutually year after year, the emitter of triode be connected with the power pins of chip, the base stage of the triode connects It connects on the cathode of zener diode and the plus earth of zener diode, the resistance is connected to the collector and base of triode Between pole.Therefore, a kind of Width funtion of R & D design adds the Switching Power Supply of surge voltage protection, is formed using metal-oxide-semiconductor and TVS pipe anti- Surge reduction voltage circuit has good social value and economic benefit, has a extensive future to improve security reliability.

Summary of the invention:

The purpose of the utility model is to overcome disadvantage of the existing technology, designs a kind of Width funtion and surge voltage is added to protect The Switching Power Supply of shield realizes the high surge for solving to generate when transformer platform area overtension and live power load switch, lightning stroke The problem of voltage and long-time high input voltage cause Switching Power Supply to damage and burst.

To achieve the goals above, the utility model relates to Width funtion add surge voltage protection Switching Power Supply main body Structure includes varistor module, three side pressure heat-sensitive modules, metal-oxide-semiconductor decompression and TVS pipe voltage-limiting protection module and Switching Power Supply mould Four funtion parts of block further include the conventional electricity of power supply, HVCC, PGND, the circuit inductance coil LN5, RCD and switching power circuit Department of the Chinese Academy of Sciences's part；Varistor module, three side pressure heat-sensitive modules, metal-oxide-semiconductor decompression and TVS pipe voltage-limiting protection module and switch power module Power information, which is cooperatively connected, carries out level Four protection to switching power circuit；UA, UB, UC and UN of the power supply of input terminal are respectively to correspond to Three-phase and four-line input ac power in A phase, B phase, C phase and N phase voltage input；RCD return routing resistance DN6, capacitor CN3, Varistor RN17 and varistor RN18, which is cooperatively connected, to be constituted；The main structure of varistor module include varistor RN1, Varistor RN2 and varistor RN3, varistor RN1 are connected in parallel between the UA of input ac power and UN, varistor RN2 is connected in parallel between the UB of input ac power and UN, and varistor RN3 is connected in parallel between the UC of input ac power and UN； The main structure of three side pressure heat-sensitive modules is by compound pressure thermistor RN4, compound pressure thermistor RN5 and compound pressure thermistor RN6 is electrically connected to form, and compound pressure thermistor RN4 is connected between 2 ends of UA and inductance coil LN5 of input ac power, Compound pressure thermistor RN5 is connected between 2 ends of UB and inductance coil LN5 of input ac power, compound pressure thermistor RN6 is connected between 2 ends of UC and inductance coil LN5 of power supply；The main body knot of metal-oxide-semiconductor decompression and TVS pipe voltage-limiting protection module Structure is electrically connected to form by diode DN8, diode DN10, diode DN20 and switching tube QN1, diode DN8, diode DN10 And it is connected in parallel between 3 ends of inductance coil LN5 and 4 ends of inductance coil LN5 after diode DN20 series connection, switching tube QN1 series connection The output end behind 3 ends of inductance coil LN5；The main structure of switch power module includes capacitor EN1, capacitor EN2 and control It is connected in parallel between 3 ends of inductance coil LN5 and 4 ends of inductance coil LN5 after coremaking piece UN1, capacitor EN1 and capacitor EN2 series connection, Control chip UN1 is connected on output end behind 4 ends of inductance coil LN5.

The utility model compared with prior art, uses input voltage for the power supply of 80Vac-500Vac, compared with input voltage Range for the general power supply of 220V/380V (tolerance is ± 20%) is wide, absorbs control chip UN1 using the circuit RCD and opens Generated peak voltage between pass carries out first order protection to switching power circuit using varistor module, using three ends It presses heat-sensitive module to carry out second level protection to switching power circuit, keeps surge voltage phase voltage clamped in 390V, using MOS Pipe decompression and TVS pipe voltage-limiting protection module carry out third level protection to switching power circuit, so that the capacitor of the rear end switching tube QN1 Voltage clamping between EN1 and capacitor EN2 carries out fourth stage guarantor to switching power circuit using switch power module to 650V Shield；Its conducting resistance is small, and loss is low, provides safe and reliable protection for the high voltage at scene and high surge lightning stroke voltage input Measure, practicability and strong applicability.

Detailed description of the invention:

Fig. 1 is the main structure circuit theory schematic diagram of the utility model.

Fig. 2 be the utility model relates to switching power circuit structural schematic diagram.

Specific embodiment:

The utility model is described further by way of example and in conjunction with the accompanying drawings.

Embodiment 1:

The Width funtion that the present embodiment is related to adds the main structure of the Switching Power Supply of surge voltage protection to include varistor mould Block 1, three side pressure heat-sensitive modules 2, metal-oxide-semiconductor (field-effect tube) decompression and TVS pipe (transient diode) voltage-limiting protection module 3 and switch 4 four funtion parts of power module further include power supply, HVCC (constant-current high-voltage DC power supply), PGND (power ground), inductance coil The conventional electrical component in the circuit LN5, RCD and switching power circuit；Varistor module 1, three side pressure heat-sensitive modules 2, metal-oxide-semiconductor drop Pressure and TVS pipe voltage-limiting protection module 3 and 4 power information of switch power module, which are cooperatively connected, carries out level Four guarantor to switching power circuit Shield；UA, UB, UC and UN of the power supply of input terminal are respectively the A phase, B phase, C phase in corresponding three-phase and four-line input ac power It is inputted with N phase voltage；RCD returns routing resistance DN6, capacitor CN3, varistor RN17 and varistor RN18 mating connection structure At；The main structure of varistor module 1 includes varistor RN1, varistor RN2 and varistor RN3, varistor RN1 is connected in parallel between the UA of input ac power and UN, and varistor RN2 is connected in parallel between the UB of input ac power and UN, Varistor RN3 is connected in parallel between the UC of input ac power and UN；The main structure of three side pressure heat-sensitive modules 2 is by compound pressure heat Quick resistance RN4, compound pressure thermistor RN5 and compound pressure thermistor RN6 are electrically connected to form, compound pressure thermistor RN4 string It is associated between 2 ends of UA and inductance coil LN5 of input ac power, compound pressure thermistor RN5 is connected on input AC electricity Between 2 ends of the UB and inductance coil LN5 in source, compound pressure thermistor RN6 is connected on the 2 of the UC and inductance coil LN5 of power supply Between end；The main structure of metal-oxide-semiconductor decompression and TVS pipe voltage-limiting protection module 3 is by diode DN8, diode DN10, diode DN20 and switching tube QN1 are electrically connected to form, and are connected in parallel on inductor wire after diode DN8, diode DN10 and diode DN20 series connection It encloses between 3 ends of LN5 and 4 ends of inductance coil LN5, switching tube QN1 is connected on output end behind 3 ends of inductance coil LN5； The main structure of switch power module 4 includes capacitor EN1, capacitor EN2 and control chip UN1, capacitor EN1 and capacitor EN2 series connection It is connected in parallel between 3 ends of inductance coil LN5 and 4 ends of inductance coil LN5 afterwards, control chip UN1 is connected on inductance coil LN5's Output end behind 4 ends.

The Width funtion that the present embodiment is related to adds the input voltage of the Switching Power Supply of surge voltage protection to be 80Vac-500Vac, The input voltage of general power supply is 220V/380V, and tolerance is ± 20%, and Width funtion adds the Switching Power Supply of surge voltage protection Input voltage range than general power supply wide input voltage range；The circuit RCD can absorb institute between control chip UN1 switch The peak voltage of generation；Varistor module 1 carries out first order protection to switching power circuit；Three side pressure heat-sensitive modules 2 are split Powered-down source circuit carries out second level protection, keeps surge voltage phase voltage clamped in 390V；Metal-oxide-semiconductor decompression and TVS pipe pressure limiting Protective module 3 carries out third level protection to the circuit of Switching Power Supply so that the capacitor EN1 and capacitor EN2 of the rear end switching tube QN1 it Between voltage clamping to 650V；Switch power module 4 carries out fourth stage protection to switching power circuit；It is varistor RN1, pressure-sensitive Resistance RN2 and varistor RN3 is the varistor of S20K510E2K7；Compound pressure thermistor RN4, compound pressure temperature-sensitive electricity Resistance RN5 and compound pressure thermistor RN6 is the three side pressure thermistors of MZ11-10E300-500RM/4D391；Diode DN8, diode DN10 and diode DN20 are the TVS pipe of SMBJ180CA, and switching tube QN1 is the metal-oxide-semiconductor of 4N90L；Capacitor EN1 and capacitor EN2 is 47Uf/400V capacitor, and control chip UN1 is the VIPER267KD chip that ST company routinely produces, control Coremaking piece UN1 built-in voltage is 1050V, and the operating ambient temperature of control chip UN1 is -40 DEG C -75 DEG C, has pressure-resistant surplus It is high, performance is good, safe and reliable and over-voltage, overcurrent and short-circuit protection function, support three-phase and four-line full-wave rectification input.

The Width funtion that the present embodiment is related to adds the Switching Power Supply of surge voltage protection to carry out the mistake that the wide scope of power supply inputs Journey are as follows: as phase voltage Vin (min)=80V, V (HVCC is to PGND)=80 × 1.732 × 1.414=196V of rear end, switch Power supply normally starts, and as phase voltage Vin (max)=500V, the movement of three side pressure heat-sensitive modules 2 keeps phase voltage clamped in 390V, Rear end is depressured by metal-oxide-semiconductor and TVS pipe voltage-limiting protection module 3 arrives the voltage clamping between capacitor EN1 and capacitor EN2 650V, it is working properly less than the built-in voltage 1050V of control chip UN1, to realize the wide scope input of Switching Power Supply.

The Width funtion that the present embodiment is related to adds the Switching Power Supply of surge voltage protection to carry out high voltage or surge voltage input Process are as follows: first varistor module 1 act, phase voltage it is clamped arrive 390V, capacitor CN13, capacitor CN17 and the capacitor of rear end Tri- 1nF/400V safety capacitors of CN18 are filtered, when normal voltage and low-voltage input, varistor module 1 and three side pressures Heat-sensitive module 2 is failure to actuate, then diode DN1, diode DN2, diode DN3, diode DN4, diode DN5, diode DN11, diode DN12 and eight EM520 rectifier diodes of diode DN13 complete full-wave rectification, pass through capacitor CN19 and capacitor Two 0.22uF/310V safety capacitor decouplings of CN20, it is then dry by the common mode inductance filtering common mode of the 40mH of inductance coil LN5 It disturbs, rear end is depressured by metal-oxide-semiconductor and TVS pipe voltage-limiting protection module 3 arrives the voltage clamping between capacitor EN1 and capacitor EN2 650V, to realize the high voltage of Switching Power Supply or inhibit high surge voltage input；Since switching tube QN1 is in pressure reduction It will appear the incomplete phenomenon of switch, from 1206 resistance of external 100 Ω in the circuit RCD of rear end transformer: varistor RN15 It with varistor RN16, can be improved VGS (video monitoring running guarantee system), switching loss reduced, in the rear end switching tube QN1 It is clamped to 650V when, V (DS)=Vin (max)+Vor+V (leakage

Sense)=650V+80V+70V=900V, it is adjusted by reducing transformer leakage inductance and RCD loop parameter, V can be made (DS) control is within 900V, and leakage inductance is small, and noise is low, so that the built-in voltage surplus of control chip UN1 is big, resistance RN7, resistance RN8 and the 390K current-limiting resistance of movement RN9 tri- 1206 can reduce the power consumption under normality and when long-time high voltage protective, Capacitor EN1 and capacitor EN2 are filtered, varistor RN11, varistor RN12, varistor RN13 and varistor RN14 For conventional equalizing resistance.

Claims (1)

1. the Switching Power Supply that a kind of Width funtion adds surge voltage protection, it is characterised in that main structure include varistor module, Three side pressure heat-sensitive modules, metal-oxide-semiconductor decompression and four funtion parts of TVS pipe voltage-limiting protection module and switch power module further include Power supply, HVCC, PGND, the circuit inductance coil LN5, RCD and switching power circuit conventional electrical component；Varistor module, Three side pressure heat-sensitive modules, metal-oxide-semiconductor decompression and TVS pipe voltage-limiting protection module and switch power module power information are cooperatively connected to switch Power circuit carries out level Four protection；UA, UB, UC and UN of the power supply of input terminal are respectively corresponding three-phase and four-line input AC electricity A phase, B phase, C phase and the input of N phase voltage in source；RCD returns routing resistance DN6, capacitor CN3, varistor RN17 and pressure-sensitive electricity RN18 mating connection is hindered to constitute；The main structure of varistor module includes varistor RN1, varistor RN2 and pressure-sensitive electricity RN3 is hindered, varistor RN1 is connected in parallel between the UA of input ac power and UN, and varistor RN2 is connected in parallel on input ac power UB and UN between, varistor RN3 is connected in parallel between the UC of input ac power and UN；The main body knot of three side pressure heat-sensitive modules Structure is electrically connected to form by compound pressure thermistor RN4, compound pressure thermistor RN5 and compound pressure thermistor RN6, compound pressure heat Quick resistance RN4 is connected between 2 ends of UA and inductance coil LN5 of input ac power, and compound pressure thermistor RN5 is connected on Between 2 ends of the UB and inductance coil LN5 of input ac power, compound pressure thermistor RN6 is connected on the UC and inductance of power supply Between 2 ends of coil LN5；The main structure of metal-oxide-semiconductor decompression and TVS pipe voltage-limiting protection module is by diode DN8, diode DN10, diode DN20 and switching tube QN1 are electrically connected to form, diode DN8, diode DN10 and diode DN20 series connection after simultaneously It is associated between 3 ends of inductance coil LN5 and 4 ends of inductance coil LN5, switching tube QN1 is connected on 3 ends of inductance coil LN5 Output end below；The main structure of switch power module includes capacitor EN1, capacitor EN2 and control chip UN1, capacitor EN1 and electricity It is connected in parallel between 3 ends of inductance coil LN5 and 4 ends of inductance coil LN5 after holding EN2 series connection, control chip UN1 is connected on inductance Output end behind 4 ends of coil LN5.