CN101699734A

CN101699734A - Circuit and method for derating in overheating and over-voltage protection of big power switch power supply

Info

Publication number: CN101699734A
Application number: CN200910185587A
Authority: CN
Inventors: 林勇; 刘杰
Original assignee: Anhui Zhengxin Kitchen Technology Co Ltd
Current assignee: Anhui Zhengxin Kitchen Technology Co Ltd
Priority date: 2009-11-20
Filing date: 2009-11-20
Publication date: 2010-04-28
Anticipated expiration: 2029-11-20
Also published as: CN101699734B

Abstract

The invention discloses a circuit and a method for derating in the overheating and over-voltage protection of a big power switch power supply. The method comprises the following steps of: acquiring voltage and temperature signals of an operating big power switch power supply; comparing the obtained voltage and temperature signals with the set voltage and temperature protection values; and if the voltage and temperature acquisition signal values of the tested operating big power switch are over the set voltage and temperature protection values respectively, namely the overheating or voltage protection occurs, gradually reducing the real-time working power of the operating big power switch power supply by using 10 percent of original working power as a derating value until the overheating or voltage protection does not occur any more. When the overheating or voltage protection occurs, by using the derating method, under a condition of not affecting operation of the big power switch power supply, the big power switch power supply is protected in real time, and the use efficiency of the big power switch power supply is obviously improved.

Description

High power switching power supply is overheated, derate circuit and method during overvoltage protection

Technical field

The present invention relates to that the field high power switching power supply is overheated, the overvoltage protection field, be specifically related to that a kind of high power switching power supply is overheated, derate circuit and method during overvoltage protection.

Background technology

High power switching power supply in the market, when overheated, overvoltage protection occurring, the protection equipment that directly shuts down makes the user can not continue use equipment.As high-power induction heating power may cause heating thing because of protection stop the heating, thereby cause the heating thing can not normally use, bring economic loss to the user; Electric welding machine causes the welding rod waste because of protection suddenly as welding for another example; As a same reason, charger can not continue charging because of protection, and causes inefficiency.

It is too high that overtemperature protection generally appears at ambient temperature, and equipment heat extraction blower fan hinders cisco unity malfunction for some reason, and equipment ventilates not smooth (in time do not clean as the air strainer dust is more, be obstructed into and out of the air port etc.); Overvoltage protection generally appears at the electric power system electric voltage exception, or the generator powered pressure is unstable, and factors such as the internal fault of equipment own cause.If the user just in use, overheated or overvoltage protection occurs, ordinary circumstance all can influence the quality of machined object.

Summary of the invention

The technical problem to be solved in the present invention provides that a kind of high power switching power supply is overheated, derate circuit and method during overvoltage protection; when overheated or overcurrent protection occurring; adopt the derate method; do not influencing under the work prerequisite of high power switching power supply, reaching the purpose of real-time guard high power switching power supply.

For addressing the above problem, technical scheme of the present invention is:

A kind of high power switching power supply is overheated, derate circuit during overvoltage protection, by pressure sampling circuit, sampled signal pulsewidth and frequency control circuit, voltage stabilizing circuit, single chip machine controlling circuit, the DC/DC converter control circuit, power amplification circuit and pwm control circuit are formed, it is characterized in that: described pressure sampling circuit is by resistance R x2, R24 and capacitor C 37 are formed, resistance R x2, R24 respectively has terminals to connect mutually by lead, another wiring termination DC power supply of resistance R x2, another terminals ground connection of resistance R 24, capacitor C 37 is connected in parallel on the two ends of resistance R 24;

Described sampled signal pulsewidth and frequency control circuit are made up of capacitor C 6, C13 and C14, transformer T2, bridge rectifier Bridge2 and optocoupler TLP521-1 (U2) and TLP521-1 (U4), capacitor C 6, C13 and C14 form filter circuit, capacitor C 6, C13 are in parallel with capacitor C 14 after connecting mutually by lead, wherein the two ends of the series circuit of being made up of capacitor C 6, C13 are connected with power connector Jpower1, line between capacitor C 6, the C13 is provided with terminals, from then on terminals are drawn lead, are connected on the power connector Jpower1; The output of filter circuit, promptly the two ends of capacitor C 14 are connected in parallel on 1,3 ends of transformer T2, and rectification circuit Bridge2 is made up of four diodes, after the input of rectification circuit Bridge2 is parallel with capacitor C 15, is carried in 2,4 ends of transformer T; Output 3 ground connection of rectification circuit Bridge2, output 1 is serially connected with inductance L 0 respectively by lead, and this output of rectification circuit Bridge2 and the line between the inductance L 0 are provided with terminals, and from then on terminals are drawn lead, serial connection capacitor C 18 back ground connection; Another terminals of inductance L 0 also by ground connection behind the lead serial connection capacitor C 18x, also are provided with terminals on these terminals of inductance L 0 and the line between the capacitor C 18x, and from then on terminals are drawn lead, are connected to a direct current power supply; Two

inputs

1,2 of optocoupler TLP521-1 (U2) are connected with connector Jphase1 after being serially connected with resistance R 3, R4 by lead respectively, also are parallel with diode D2 between two inputs of optocoupler TLP521-1 (U2) 1,2; Be connected to wire jumper JP1 between two outputs 3,4 of optocoupler TLP521-1 (U2), wherein an end of the corresponding access with wire jumper JP1 of the output 4 of optocoupler TLP521-1 (U2) also connects+DC power supply of 5V altogether, line between one end of the corresponding access with wire jumper JP1 of the output 3 of optocoupler TLP521-1 (U2) is provided with terminals, from then on terminals are drawn lead, are connected with the resistance R 25 and the capacitor C 17 back ground connection that are in parallel; Two

inputs

1,2 of optocoupler TLP521-1 (U4) insert connector Jin1 by lead serial connection swept resistance R29 and resistance R 01 back respectively, two outputs 3,4 of optocoupler TLP521-1 (U4) are respectively by ground connection behind lead series resistor R34 and the diode D7, wherein also be provided with terminals on the output 4 of optocoupler TLP521-1 (U4) and the line between the diode D7, from then on terminals are drawn lead, receive terminals of capacitor C 01 and resistance R 31 respectively, another terminals ground connection of capacitor C 01, another wiring termination+18V DC power supply of resistance R 31; Also lead to lead on the output 3 of optocoupler TLP521-1 (U4), be respectively equipped with three terminals on the lead, these three terminals are wired to terminals of capacitor C 32, resistance R 40 and the negative electrode of diode D6 respectively, another terminals of capacitor C 32 and resistance R 34 be ground connection altogether, another terminals of resistance R 40 insert the main end, and the anode of diode D6 connects+the 5V DC power supply;

Described voltage stabilizing circuit includes voltage-stabiliser tube 7818, Vin end and Vout end connect a direct current power supply and+18V DC power supply respectively, GND holds ground connection;

Described single chip machine controlling circuit includes single chip computer AT MEGA8 (U8), the PD0 end of single chip computer AT MEGA8 (U8) is connected to connector CON7 with the PD1 end altogether by lead, the PB6 end is connected to connector CON4 with the PB7 end altogether by lead, PB2 end, PB3 end, PB4 end and PB5 are connected to connector CON5 altogether by lead, PC2 end, PC3 end and PC4 end by lead respectively correspondence be connected to a connector CON2; Be respectively equipped with terminals from the line between the connector CON2 of the PD2 of single chip computer AT MEGA8 (U8) end, PC3 end and PC4 end and corresponding connection, from each terminals respectively to the left and right both sides draw lead, be total to ground connection after being connected in series capacitor C 36, C35, C34 on the wherein left lead respectively, connect altogether behind series resistor R38, R37, the R36 respectively on the lead of right side+the 5V DC power supply; The PD7 end of single chip computer AT MEGA8 (U8) is by lead serial connection capacitor C 7 back ground connection, wherein the line between PD7 end and the capacitor C 7 is provided with terminals, draw the terminals that lead is received the change resistance POT2 that slides from terminals, other two terminals that become resistance POT2 that slide connect respectively+5V DC power supply and ground; The PC6 of single chip computer AT MEGA8 (U8) end is received the resistance R 26 that is in parallel and terminals of capacitor C 41, another wiring termination+5V DC power supply of resistance R 26, another terminals ground connection of capacitor C 41 by lead; The PB0 end of single chip computer AT MEGA8 (U8) is serially connected with resistance R 19 backs by lead and inserts the shutdown end; The PB1 end of single chip computer AT MEGA8 (U8) is connected with the resistance R 39 amplifier LM358 of mutual series connection by lead, line between resistance R 39 and the amplifier LM358 is provided with two terminals, the terminals that wherein connect capacitor C 16 are the main end, these two terminals are concatenated into the terminals of capacitor C 16 and wire jumper JP2 respectively by lead, another terminals ground connection of capacitor C 16, another wiring termination+5V DC power supply of wire jumper JP2; The normal phase input end of amplifier LM358 is connected with resistance R 39, be connected in series to slide by lead between the inverting input of amplifier LM358 and the output and become resistance R30, the amplifier LM358 inverting input and the line that becomes between the resistance R30 that slides are provided with terminals, from then on terminals are drawn lead, receive terminals of resistance R 2, another terminals ground connection of resistance R 2; The positive-negative power end of amplifier LM358 connects respectively+18V DC power supply and ground, and the positive power source terminal of amplifier LM358 is also by lead serial connection capacitor C 2 back ground connection; Wherein, resistance R 39 and capacitor C 16 are formed the D/A change-over circuit, and amplifier LM358 and peripheral circuit thereof are formed the difference regulating circuit;

Described DC/DC converter control circuit includes the ambipolar linear Integrated chip of monolithic MC34063, the IPK of the ambipolar linear Integrated chip of monolithic MC34063 end, IDC end and ISWC end are by connecing altogether with the VCC end behind the lead series resistor R6+DC power supply of 18V, the TCAP of the ambipolar linear Integrated chip of monolithic MC34063 holds terminals receiving two capacitor C parallel with one another 3 and C3x by lead, and another terminals of capacitor C 3 and C3x are ground connection altogether; The ISWE end of the ambipolar linear Integrated chip of monolithic MC34063 is by lead serial connection diode D1, and the negative electrode of diode D1 links to each other with the ISWE end, wherein the ISWE of the ambipolar linear Integrated chip of monolithic MC34063 end is provided with terminals with the line of diode D1, from then on terminals are drawn lead, being serially connected with ground connection behind inductance L 1 and three capacitor C parallel with one another 24, C30 and the C31, capacitor C 24, C30 and C31 also connect altogether+DC power supply of 5V; The COMP end of the ambipolar linear Integrated chip of monolithic MC34063 is by ground connection behind the lead series resistance R10; On the line between the COMP of the ambipolar linear Integrated chip of monolithic MC34063 end and the resistance R 10 and be respectively equipped with terminals on the line between inductance L 1 and the electric capacity, be in series with resistance R 8 by lead between these two terminals;

Described power amplification circuit is made up of triode Qa5, Qa6, Qa7, Qa8, Qb5, Qb6, Qb7, Qb8, the emitter of triode Qa5 is connected by lead with the emitter of triode Qa7, the collector electrode of the collector electrode of triode Qa5 and triode Qa7 connects respectively+18V DC power supply and ground, the base stage of the base stage of triode Qa5 and triode Qa7 inserts output outa behind the connecting resistance Ra3 altogether, and the collector electrode of triode Qa5 is also by ground connection behind the lead serial connection capacitor C a1; The emitter of triode Qa6 is connected by lead with the emitter of triode Qa8, the collector electrode of the collector electrode of triode Qa6 and triode Qa8 connects respectively+18V DC power supply and ground, the base stage of the base stage of triode Qa6 and triode Qa8 inserts output outb behind the connecting resistance Ra4 altogether, and the collector electrode of triode Qa6 is also by ground connection behind the lead serial connection capacitor C a4; Line between the emitter of the emitter of triode Qa5 and triode Qa7 is provided with first terminals, line between the collector electrode of the collector electrode of triode Qa6 and triode Qa8 is provided with second terminals, first terminals and second terminals are wired to connector Ja1 respectively, also be respectively equipped with terminals on the line between first terminals, second terminals and the connector Ja1, from then on two terminals are drawn lead, connect ground connection behind diode Da3, the Da4 respectively; The emitter of triode Qb5 is connected by lead with the emitter of triode Qb7, the collector electrode of the collector electrode of triode Qb5 and triode Qb7 connects respectively+18V DC power supply and ground, the base stage of the base stage of triode Qb5 and triode Qb7 inserts output outc behind the connecting resistance Rb3 altogether, and the collector electrode of triode Qb5 is also by ground connection behind the lead serial connection capacitor C b3; The emitter of triode Qb6 is connected by lead with the emitter of triode Qb8, the collector electrode of the collector electrode of triode Qa6 and triode Qb8 connects respectively+18V DC power supply and ground, the base stage of the base stage of triode Qb6 and triode Qb8 inserts output outd behind the connecting resistance Rb4 altogether, and the collector electrode of triode Qb6 is also by ground connection behind the lead serial connection capacitor C b4; Line between the emitter of the emitter of triode Qb5 and triode Qb7 is provided with first terminals, line between the collector electrode of the collector electrode of triode Qb6 and triode Qb8 is provided with second terminals, first terminals and second terminals are wired to connector Jb1 respectively, also be respectively equipped with terminals on the line between first terminals, second terminals and the connector Jb1, from then on two terminals are drawn lead, connect ground connection behind diode Db3, the Db4 respectively;

Described pwm control circuit includes the socket chip, and the I_SENSE0 end of socket chip is connected to connector Jsense1 by lead, and the shutdown control end inserts the PB0 end of single chip computer AT MEGA8 (U8) in the described single chip machine controlling circuit;

A kind of high power switching power supply is overheated, derate method during overvoltage protection, and it is characterized in that: its method may further comprise the steps:

(1), gathers the voltage and the temperature signal of the high power switching power supply moving, the voltage of the high power switching power supply that is being moved and temperature sampling signal;

(2), the voltage of the high power switching power supply of gained and the voltage and the temperature protection value of temperature sampling signal and setting are compared, and the nominal operation power of the high power switching power supply that moving of record;

(3), draw voltage and the voltage of temperature sampling signal and setting and the comparative result that the temperature protection value compares of high power switching power supply according to above-mentioned steps, if the voltage of the tested high power switch that is moving and temperature sampling signal value are respectively greater than voltage and the temperature protection value set, when overheated or overvoltage protection promptly occurring, then reduce the operating power of high power switching power supply, make high power switching power supply under the state that is lower than nominal operation power, move, if this moment no longer occurs overheated or overvoltage protection, the operating power after then high power switching power supply reduces continues operation; If overheated or overvoltage protection still appears in this moment, reduce the operating power of high power switching power supply again, as this moment no longer occurring overheated or overvoltage protection, then high power switching power supply continues operation under this operating power state; If overheated or overvoltage protection still occurs, continue to reduce the operating power of high power switching power supply again, repeat above-mentioned steps repeatedly, up to no longer occur overheated or overvoltage protection till.

Described high power switching power supply is overheated, derate method during overvoltage protection, and the amount that it is characterized in that described each reduction operating power is the 10-5% of nominal operation power.

Beneficial effect of the present invention:

The present invention is not influencing under the work prerequisite of high power switching power supply occurring overheated or during overcurrent protection, adopting the derate method, real-time guard high power switching power supply, obviously improved the use actual effect of high power switching power supply.

Description of drawings

Fig. 1 is a circuit structure schematic diagram of the present invention.

Embodiment

Referring to Fig. 1,2, a kind of high power switching power supply is overheated, derate circuit during overvoltage protection, by pressure sampling circuit, sampled signal pulsewidth and frequency control circuit, voltage stabilizing circuit, single chip machine controlling circuit, the DC/DC converter control circuit, power amplification circuit and pwm control circuit are formed, pressure sampling circuit is by resistance R x2, R24 and capacitor C 37 are formed, resistance R x2, R24 respectively has terminals to connect mutually by lead, another wiring termination DC power supply of resistance R x2, another terminals ground connection of resistance R 24, capacitor C 37 is connected in parallel on the two ends of resistance R 24;

Sampled signal pulsewidth and frequency control circuit are made up of capacitor C 6, C13 and C14, transformer T2, bridge rectifier Bridge2 and optocoupler TLP521-1 (U2) and TLP521-1 (U4), capacitor C 6, C13 and C14 form filter circuit, capacitor C 6, C13 are in parallel with capacitor C 14 after connecting mutually by lead, wherein the two ends of the series circuit of being made up of capacitor C 6, C13 are connected with power connector Jpower1, line between capacitor C 6, the C13 is provided with terminals, from then on terminals are drawn lead, are connected on the power connector Jpower1; The output of filter circuit, promptly the two ends of capacitor C 14 are connected in parallel on 1,3 ends of transformer T2, and rectification circuit Bridge2 is made up of four diodes, after the input of rectification circuit Bridge2 is parallel with capacitor C 15, is carried in 2,4 ends of transformer T; Output 3 ground connection of rectification circuit Bridge2, output 1 is serially connected with inductance L 0 respectively by lead, and this output of rectification circuit Bridge2 and the line between the inductance L 0 are provided with terminals, and from then on terminals are drawn lead, serial connection capacitor C 18 back ground connection; Another terminals of inductance L 0 also by ground connection behind the lead serial connection capacitor C 18x, also are provided with terminals on these terminals of inductance L 0 and the line between the capacitor C 18x, and from then on terminals are drawn lead, are connected to a direct current power supply; Two

inputs

Voltage stabilizing circuit includes voltage-stabiliser tube 7818, Vin end and Vout end connect a direct current power supply and+18V DC power supply respectively, GND holds ground connection;

Single chip machine controlling circuit includes single chip computer AT MEGA8 (U8), the PD0 end of single chip computer AT MEGA8 (U8) is connected to connector CON7 with the PD1 end altogether by lead, the PB6 end is connected to connector CON4 with the PB7 end altogether by lead, PB2 end, PB3 end, PB4 end and PB5 are connected to connector CON5 altogether by lead, PC2 end, PC3 end and PC4 end by lead respectively correspondence be connected to a connector CON2; Be respectively equipped with terminals from the line between the connector CON2 of the PD2 of single chip computer AT MEGA8 (U8) end, PC3 end and PC4 end and corresponding connection, from each terminals respectively to the left and right both sides draw lead, be total to ground connection after being connected in series capacitor C 36, C35, C34 on the wherein left lead respectively, connect altogether behind series resistor R38, R37, the R36 respectively on the lead of right side+the 5V DC power supply; The PD7 end of single chip computer AT MEGA8 (U8) is by lead serial connection capacitor C 7 back ground connection, wherein the line between PD7 end and the capacitor C 7 is provided with terminals, draw the terminals that lead is received the change resistance POT2 that slides from terminals, other two terminals that become resistance POT2 that slide connect respectively+5V DC power supply and ground; The PC6 of single chip computer AT MEGA8 (U8) end is received the resistance R 26 that is in parallel and terminals of capacitor C 41, another wiring termination+5V DC power supply of resistance R 26, another terminals ground connection of capacitor C 41 by lead; The PB0 end of single chip computer AT MEGA8 (U8) is serially connected with resistance R 19 backs by lead and inserts the shutdown end; The PB1 end of single chip computer AT MEGA8 (U8) is connected with the resistance R 39 amplifier LM358 of mutual series connection by lead, line between resistance R 39 and the amplifier LM358 is provided with two terminals, the terminals that wherein connect capacitor C 16 are the main end, these two terminals are concatenated into the terminals of capacitor C 16 and wire jumper JP2 respectively by lead, another terminals ground connection of capacitor C 16, another wiring termination+5V DC power supply of wire jumper JP2; The normal phase input end of amplifier LM358 is connected with resistance R 39, be connected in series to slide by lead between the inverting input of amplifier LM358 and the output and become resistance R30, the amplifier LM358 inverting input and the line that becomes between the resistance R30 that slides are provided with terminals, from then on terminals are drawn lead, receive terminals of resistance R 2, another terminals ground connection of resistance R 2; The positive-negative power end of amplifier LM358 connects respectively+18V DC power supply and ground, and the positive power source terminal of amplifier LM358 is also by lead serial connection capacitor C 2 back ground connection; Wherein, resistance R 39 and capacitor C 16 are formed the D/A change-over circuit, and amplifier LM358 and peripheral circuit thereof are formed the difference regulating circuit;

The DC/DC converter control circuit includes the ambipolar linear Integrated chip of monolithic MC34063, the IPK of the ambipolar linear Integrated chip of monolithic MC34063 end, IDC end and ISWC end are by connecing altogether with the VCC end behind the lead series resistor R6+DC power supply of 18V, the TCAP of the ambipolar linear Integrated chip of monolithic MC34063 holds terminals receiving two capacitor C parallel with one another 3 and C3x by lead, and another terminals of capacitor C 3 and C3x are ground connection altogether; The ISWE end of the ambipolar linear Integrated chip of monolithic MC34063 is by lead serial connection diode D1, and the negative electrode of diode D1 links to each other with the ISWE end, wherein the ISWE of the ambipolar linear Integrated chip of monolithic MC34063 end is provided with terminals with the line of diode D1, from then on terminals are drawn lead, being serially connected with ground connection behind inductance L 1 and three capacitor C parallel with one another 24, C30 and the C31, capacitor C 24, C30 and C31 also connect altogether+DC power supply of 5V; The COMP end of the ambipolar linear Integrated chip of monolithic MC34063 is by ground connection behind the lead series resistance R10; On the line between the COMP of the ambipolar linear Integrated chip of monolithic MC34063 end and the resistance R 10 and be respectively equipped with terminals on the line between inductance L 1 and the electric capacity, be in series with resistance R 8 by lead between these two terminals;

Power amplification circuit is made up of triode Qa5, Qa6, Qa7, Qa8, Qb5, Qb6, Qb7, Qb8, the emitter of triode Qa5 is connected by lead with the emitter of triode Qa7, the collector electrode of the collector electrode of triode Qa5 and triode Qa7 connects respectively+18V DC power supply and ground, the base stage of the base stage of triode Qa5 and triode Qa7 inserts output outa behind the connecting resistance Ra3 altogether, and the collector electrode of triode Qa5 is also by ground connection behind the lead serial connection capacitor C a1; The emitter of triode Qa6 is connected by lead with the emitter of triode Qa8, the collector electrode of the collector electrode of triode Qa6 and triode Qa8 connects respectively+18V DC power supply and ground, the base stage of the base stage of triode Qa6 and triode Qa8 inserts output outb behind the connecting resistance Ra4 altogether, and the collector electrode of triode Qa6 is also by ground connection behind the lead serial connection capacitor C a4; Line between the emitter of the emitter of triode Qa5 and triode Qa7 is provided with first terminals, line between the collector electrode of the collector electrode of triode Qa6 and triode Qa8 is provided with second terminals, first terminals and second terminals are wired to connector Ja1 respectively, also be respectively equipped with terminals on the line between first terminals, second terminals and the connector Ja1, from then on two terminals are drawn lead, connect ground connection behind diode Da3, the Da4 respectively; The emitter of triode Qb5 is connected by lead with the emitter of triode Qb7, the collector electrode of the collector electrode of triode Qb5 and triode Qb7 connects respectively+18V DC power supply and ground, the base stage of the base stage of triode Qb5 and triode Qb7 inserts output outc behind the connecting resistance Rb3 altogether, and the collector electrode of triode Qb5 is also by ground connection behind the lead serial connection capacitor C b3; The emitter of triode Qb6 is connected by lead with the emitter of triode Qb8, the collector electrode of the collector electrode of triode Qa6 and triode Qb8 connects respectively+18V DC power supply and ground, the base stage of the base stage of triode Qb6 and triode Qb8 inserts output outd behind the connecting resistance Rb4 altogether, and the collector electrode of triode Qb6 is also by ground connection behind the lead serial connection capacitor C b4; Line between the emitter of the emitter of triode Qb5 and triode Qb7 is provided with first terminals, line between the collector electrode of the collector electrode of triode Qb6 and triode Qb8 is provided with second terminals, first terminals and second terminals are wired to connector Jb1 respectively, also be respectively equipped with terminals on the line between first terminals, second terminals and the connector Jb1, from then on two terminals are drawn lead, connect ground connection behind diode Db3, the Db4 respectively;

Pwm control circuit includes the socket chip, and the I_SENSE0 end of socket chip is connected to connector Jsense1 by lead, and the shutdown control end inserts the PB0 end of single chip computer AT MEGA8 (U8) in the single chip machine controlling circuit;

A kind of high power switching power supply is overheated, derate during overvoltage protection, and its method may further comprise the steps:

(2), the voltage of the high power switching power supply of gained and the voltage and the temperature protection value of temperature sampling signal and setting are compared, and the operating power of the high power switching power supply that moving of record, be 20KW;

(3), draw voltage and the voltage of temperature sampling signal and setting and the comparative result that the temperature protection value compares of high power switching power supply according to above-mentioned steps, if the voltage of the tested high power switch that is moving and temperature sampling signal value are respectively greater than voltage and the temperature protection value set, when overheated or overvoltage protection promptly occurring, then reduce 10% of high power switching power supply initialization power 20KW, make high power switching power supply move as operating power with 18KW, if this moment no longer occurs overheated or overvoltage protection, then high power switching power supply continues operation with 18KW as operating power; If this moment still occurs overheated or overvoltage protection, the operating power of high power switching power supply comes back to initialization power 20KW, fall 10% power again this moment on the basis of the operating power 18KW that falls for the first time, as this moment no longer occurring overheated or overvoltage protection, then high power switching power supply continues operation with 16.2KW as operating power; If overheated or overvoltage protection still occurs, the operating power of high power switching power supply comes back to initialization power, fall 10% power again this moment on the basis of the operating frequency 16.2KW that falls for the second time, as this moment no longer occurring overheated or overvoltage protection, then high power switching power supply continues operation with 14.58KW power as operating power; If overheated or overvoltage protection still occurs; the operating power of high power switching power supply comes back to initialization power 20KW; continue according to the method described above again with original real-time working power 10% as derate, reduce real-time working power, up to no longer occur overheated or overvoltage protection till.

Claims

1. a high power switching power supply is overheated, derate circuit during overvoltage protection, by pressure sampling circuit, sampled signal pulsewidth and frequency control circuit, voltage stabilizing circuit, single chip machine controlling circuit, the DC/DC converter control circuit, power amplification circuit and pwm control circuit are formed, it is characterized in that: described pressure sampling circuit is by resistance R x2, R24 and capacitor C 37 are formed, resistance R x2, R24 respectively has terminals to connect mutually by lead, another wiring termination DC power supply of resistance R x2, another terminals ground connection of resistance R 24, capacitor C 37 is connected in parallel on the two ends of resistance R 24;

Described sampled signal pulsewidth and frequency control circuit are made up of capacitor C 6, C13 and C14, transformer T2, bridge rectifier Bridge2 and optocoupler TLP521-1 (U2) and TLP521-1 (U4), capacitor C 6, C13 and C14 form filter circuit, capacitor C 6, C13 are in parallel with capacitor C 14 after connecting mutually by lead, wherein the two ends of the series circuit of being made up of capacitor C 6, C13 are connected with power connector Jpower1, line between capacitor C 6, the C13 is provided with terminals, from then on terminals are drawn lead, are connected on the power connector Jpower1; The output of filter circuit, promptly the two ends of capacitor C 14 are connected in parallel on 1,3 ends of transformer T2, and rectification circuit Bridge2 is made up of four diodes, after the input of rectification circuit Bridge2 is parallel with capacitor C 15, is carried in 2,4 ends of transformer T; Output 3 ground connection of rectification circuit Bridge2, output 1 is serially connected with inductance L 0 respectively by lead, and this output of rectification circuit Bridge2 and the line between the inductance L 0 are provided with terminals, and from then on terminals are drawn lead, serial connection capacitor C 18 back ground connection; Another terminals of inductance L 0 also by ground connection behind the lead serial connection capacitor C 18x, also are provided with terminals on these terminals of inductance L 0 and the line between the capacitor C 18x, and from then on terminals are drawn lead, are connected to a direct current power supply; Two inputs 1,2 of optocoupler TLP521-1 (U2) are connected with connector Jphase1 after being serially connected with resistance R 3, R4 by lead respectively, also are parallel with diode D2 between two inputs of optocoupler TLP521-1 (U2) 1,2; Be connected to wire jumper JP1 between two outputs 3,4 of optocoupler TLP521-1 (U2), wherein an end of the corresponding access with wire jumper JP1 of the output 4 of optocoupler TLP521-1 (U2) also connects+DC power supply of 5V altogether, line between one end of the corresponding access with wire jumper JP1 of the output 3 of optocoupler TLP521-1 (U2) is provided with terminals, from then on terminals are drawn lead, are connected with the resistance R 25 and the capacitor C 17 back ground connection that are in parallel; Two inputs 1,2 of optocoupler TLP521-1 (U4) insert connector Jin1 by lead serial connection swept resistance R29 and resistance R 01 back respectively, two outputs 3,4 of optocoupler TLP521-1 (U4) are respectively by ground connection behind lead series resistor R34 and the diode D7, wherein also be provided with terminals on the output 4 of optocoupler TLP521-1 (U4) and the line between the diode D7, from then on terminals are drawn lead, receive terminals of capacitor C 01 and resistance R 31 respectively, another terminals ground connection of capacitor C 01, another wiring termination+18V DC power supply of resistance R 31; Also lead to lead on the output 3 of optocoupler TLP521-1 (U4), be respectively equipped with three terminals on the lead, these three terminals are wired to terminals of capacitor C 32, resistance R 40 and the negative electrode of diode D6 respectively, another terminals of capacitor C 32 and resistance R 34 be ground connection altogether, another terminals of resistance R 40 insert the main end, and the anode of diode D6 connects+the 5V DC power supply;

2. derate method during overheated, the overvoltage protection of a high power switching power supply, it is characterized in that: its method may further comprise the steps:

3. high power switching power supply according to claim 2 is overheated, derate method during overvoltage protection, and the amount that it is characterized in that described each reduction operating power is the 10-5% of nominal operation power.