CN203536942U - A novel ring choke converter output overvoltage protection circuit - Google Patents
A novel ring choke converter output overvoltage protection circuit Download PDFInfo
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- CN203536942U CN203536942U CN201320687667.4U CN201320687667U CN203536942U CN 203536942 U CN203536942 U CN 203536942U CN 201320687667 U CN201320687667 U CN 201320687667U CN 203536942 U CN203536942 U CN 203536942U
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Abstract
The utility model discloses a novel ring choke converter output overvoltage protection circuit. Flyback oscillation is achieved by a PWM control module, a MOS transistor, a transformer, and a current-limiting resistor. An optical coupler chip achieves circuit feedback. A voltage-regulator tube ZD1, a voltage-regulator tube ZD2, a NPN-type triode, and a reference source chip are used for achieving output overvoltage detection and feeding a result back to the PWM control module via the optical coupler chip. In an embodiment of the utility model, the voltage-regulator tube ZD1 is used as a first detection guarantee and a protection circuit formed by the voltage-regulator tube ZD1, the reference source chip IC1, and the NPN-type triode Q4 is used as a second detection guarantee such that double detection guarantees are achieved and a detection result is fed back to the PWM control module via the optical coupler chip. The novel ring choke converter output overvoltage protection circuit has advantages of simple circuit structure, low cost, accurate detection, and high protective performance.
Description
Technical field
The utility model relates to switching power converters technical field, is specifically related to a kind of novel trans exciting converter output overvoltage protection circuit.
Background technology
Auto-excitation type anti exciting converter is commonly referred to RCC(Ring Choke Converter), the Switching Power Supply based on RCC mode does not need external clock, and operating frequency and duty ratio are all subject to the control of input voltage and output current.
In anti exciting converter, generally include: PWM control module, metal-oxide-semiconductor, transformer and current-limiting resistance, voltage input end connects equipment ground by transformer primary side coil, metal-oxide-semiconductor drain electrode and source electrode, current-limiting resistance successively, the grid that PWM control module connects metal-oxide-semiconductor is used for controlling metal-oxide-semiconductor conducting or cut-off, and transformer secondary coil is powered to voltage output end through rectifier diode and output filtering module successively.The multiplex transistor circuit realization of existing PWM control module and metal-oxide-semiconductor and transformer form flyback oscillating circuit jointly.
Yet existing anti exciting converter exists feedback control loop to detect inaccuracy, and overvoltage protection detects the problems such as inefficacy, circuit structure complexity, and the performance of whole power supply has been produced to considerable influence.
Utility model content
The utility model provides a kind of novel trans exciting converter output overvoltage protection circuit, can address the above problem.
A kind of novel trans exciting converter output overvoltage protection circuit that the utility model embodiment provides, comprise: PWM control module, metal-oxide-semiconductor, transformer and current-limiting resistance, voltage input end Vin+ is successively by transformer primary side coil, metal-oxide-semiconductor drain electrode and source electrode, current-limiting resistance connects equipment ground, the grid that PWM control module connects metal-oxide-semiconductor is used for controlling metal-oxide-semiconductor conducting or cut-off, transformer secondary coil is powered to voltage output end Vo through rectifier diode and output filtering module successively, also comprise: opto-coupler chip U1, NPN type triode Q4 and a reference source chip IC 1, rectifier diode negative electrode connects photodiode anode in opto-coupler chip U1 through a voltage-stabiliser tube ZD1, described photodiode cathode connects the cathode connection terminal of a reference source chip IC 1, the anodic bonding power supply ground of a reference source chip IC 1, voltage output end Vo is successively through a resistance R 13, one resistance R 14 connects power supply ground, the base pressure of a reference source chip IC 1 arranges end and is connected on the tie point of resistance R 13 and resistance R 14, the output of output filtering module is successively through a voltage-stabiliser tube ZD2, one resistance R 12 is connected to the base stage of NPN type triode Q4, the collector electrode of NPN type triode Q4 connects described photodiode cathode, the emitter of NPN type triode Q4 connects power supply ground, in opto-coupler chip U1, the voltage ratio of the collector electrode of phototriode connection PWM control module is held, in opto-coupler chip U1, the emitter of phototriode connects equipment ground.
Preferably, described a reference source chip IC 1 adopts TL431 chip.
Preferably, also comprise one with the ancillary coil of transformer primary side coil coupling, ancillary coil is powered to PWM control module.
Preferably, the cathode connection terminal of a reference source chip IC 1 arranges to hold with base pressure and is connected a capacitor C 12.
Technique scheme can be found out; because the utility model embodiment is usingd voltage-stabiliser tube ZD1 as first detection guarantee; using protective circuit that voltage-stabiliser tube ZD2, a reference source chip IC 1 and NPN type triode Q4 form as the second detection guarantee; realize double check guarantee and feed back to PWM control module by opto-coupler chip U1; circuit structure is simple; cost is low, and detects accurately, and barrier propterty is high.
Accompanying drawing explanation
In order to be illustrated more clearly in the utility model embodiment or technical scheme of the prior art, to the accompanying drawing of required use in embodiment or description of the Prior Art be briefly described below, apparently, accompanying drawing in the following describes is only embodiment more of the present utility model, for those of ordinary skills, do not paying under the prerequisite of creative work, can also obtain according to these accompanying drawings other accompanying drawing.
Fig. 1 is circuit structure block diagram in the utility model embodiment;
Fig. 2 is circuit theory diagrams concrete in the utility model embodiment.
Embodiment
Below in conjunction with the accompanying drawing in the utility model embodiment, the technical scheme in the utility model embodiment is clearly and completely described, obviously, described embodiment is only the utility model part embodiment, rather than whole embodiment.Embodiment based in the utility model, those of ordinary skills are not making all other embodiment that obtain under creative work prerequisite, all belong to the scope of the utility model protection.
Embodiment:
The utility model embodiment provides a kind of novel trans exciting converter output overvoltage protection circuit; as shown in Figures 1 and 2; comprise: PWM control module, metal-oxide-semiconductor Q1, transformer T1 and current-limiting resistance R9; voltage input end Vin+ connects equipment ground by transformer T1 primary coil, metal-oxide-semiconductor Q1 drain electrode and source electrode, current-limiting resistance R9 successively; the grid that PWM control module connects metal-oxide-semiconductor Q1 is used for controlling metal-oxide-semiconductor Q1 conducting or cut-off, and transformer T1 secondary coil is powered to voltage output end Vo through rectifier diode D2 and inductance L 1 successively.
This novel trans exciting converter output overvoltage protection circuit also comprises: opto-coupler chip U1, NPN type triode Q4 and a reference source chip IC 1, rectifier diode D2 negative electrode connects photodiode anode in opto-coupler chip U1 through a voltage-stabiliser tube ZD1, the negative electrode of described photodiode connects the cathode connection terminal of a reference source chip IC 1, the anodic bonding power supply ground of a reference source chip IC 1, voltage output end Vo is successively through a resistance R 13, one resistance R 14 connects power supply ground, the base pressure of a reference source chip IC 1 arranges end and is connected on the tie point of resistance R 13 and resistance R 14, the output of output filtering module is successively through a voltage-stabiliser tube ZD2, one resistance R 12 is connected to the base stage of NPN type triode Q4, the collector electrode of NPN type triode Q4 connects the negative electrode of described photodiode, the emitter of NPN type triode Q4 connects power supply ground, in opto-coupler chip U1, the voltage ratio of the collector electrode of phototriode connection PWM control module is held, in opto-coupler chip U1, the emitter of phototriode connects equipment ground.The chip IC of a reference source described in the present embodiment 1 adopts TL431 chip, has voltage control feature accurately.
Be understandable that, the feedback receiving terminal of PWM control module is for receiving the feedback signal (being reflected in the emitter of described phototriode) of opto-coupler chip output, thereby adjust its control signal to metal-oxide-semiconductor grid according to this feedback signal, concrete control mode, those skilled in the art can be known according to existing knowledge, repeat no more herein.
In order to increase control stability, prevent from disturbing, in the present embodiment, the cathode connection terminal of a reference source chip IC 1 arranges to hold with base pressure and is connected a capacitor C 12.
Be understandable that, for the circuit formation of PWM control module, those skilled in the art can obtain by existing anti exciting converter knowledge, in the present embodiment, in order further to realize the stability of power supply, adopt the PWM control module of following structure.
As shown in Figure 2, this anti exciting converter has comprised: transformer T1, metal-oxide-semiconductor Q1 and current-limiting resistance R9, voltage input end Vin+ place has increased the input filter module consisting of capacitor C 1, inductance L 2 and capacitor C 2, input voltage passes through successively the primary coil of transformer T1 after after filtering, the drain electrode of metal-oxide-semiconductor Q1 and source electrode, current-limiting resistance R9 to equipment ground, the coupling energy on transformer T1 secondary coil is exported to voltage output end Vo through rectifier diode D2 and the output filtering module that consists of capacitor C 10, inductance L 1 and capacitor C 9 successively.Voltage input end Vin+ is also through a voltage stabilizing didoe ZD3, resistance R 20 is connected to the base stage of a NPN type triode Q5, the grounded emitter of this NPN type triode Q5, collector electrode is connected to the pressure feedback port VREF of PWM control module, once input terminal voltage is too high, it punctures conducting voltage stabilizing didoe ZD3 and makes NPN type triode Q5 conducting, the voltage of pressure feedback port VREF is dragged down, PWM control module is quit work, protect whole power module, concrete structure and operation principle those skilled in the art for PWM control module can be known by prior art, repeat no more herein, the ancillary coil T2 that PWM control module in this anti exciting converter comprises and transformer T1 is coupled, the coupled voltages of this ancillary coil, after resistance R 3, is filtered by capacitor C 2, obtains voltage comparatively stably and is used for powering to PWM control module.For other peripheral circuits in PWM module, forming can be directly with reference to accompanying drawing 2.
Triode Q2 and triode Q3 in the utility model embodiment, have also been set up, the voltage of output filtering module output is also connected to the collector electrode of triode Q2 and the collector electrode of triode Q3 through resistance R 2 and resistance R 1 respectively, the collector electrode of triode Q2 is connected with the base stage of triode Q3, the emitter of triode Q2 connects equipment ground, the base stage of triode Q2 is through resistance R 20 ground connection, the base stage of triode Q2 is also passed through resistance R 19 successively, resistance R 5, resistance R 7, resistance R 9 connects equipment ground, the tie point of resistance R 5 and resistance R 7 connects the current detecting end of PWM control module, this current detecting end is also connected to voltage input end Vin+ through a resistance R 4, this current detecting end also connects equipment ground through a capacitor C 4, the tie point of resistance R 19 and resistance R 5 is connected to the pressure feedback port VREF of PWM control module, the base stage of triode Q3 connects equipment ground through a capacitor C 11, the emitter of triode Q3 connects the power supply side of PWM module, as can be seen here, when voltage input end Vin+ normally inputs, the input voltage of voltage input end Vin+ is stored in capacitor C 4 through resistance R 4, and by resistance R 5, then by the first biasing resistor R19 and the first resistance R 20, make a NPN triode Q2 conducting, thereby the base voltage of the 2nd NPN triode Q3 is dragged down, make the 2nd NPN triode Q3 cut-off, now the feeder ear of PWM control module is able to normal work by ancillary coil power supply.
When there is output short-circuit in anti exciting converter, the voltage of its output is 0V, the output voltage of ancillary coil is also down to 0V, the Power supply terminal voltage of PWM control module is that 0V quits work, because the voltage input of reference voltage terminal VC1 is synchronizeed with the startup of this PWM control module, the input of the voltage at reference voltage terminal VC1 place is also 0, without input, a NPN triode Q2 enters cut-off state, the voltage of voltage input end Vin+ input acts on the base stage of the 2nd NPN triode Q3 through the second biasing resistor R2, the 2nd NPN triode Q3 conducting, the voltage of voltage input end Vin+ input is to the feeder ear power supply of PWM control module, PWM control module is restarted, under the state not being excluded in short-circuit condition, can repeat above-mentioned action.
When output voltage is too high; voltage-stabiliser tube ZD1 is switched on; flow through the electric current of voltage-stabiliser tube ZD1 through the photodiode of opto-coupler chip U1; make the phototriode conducting of opto-coupler chip; the voltage that the voltage ratio of PWM control module is held is dragged down; and then reduce the duty ratio of switching tube (metal-oxide-semiconductor), thus reduce output voltage, realize the function of protection power source and load.
When output voltage raises, output voltage is after resistance R 13 and resistance R 14 dividing potential drops, compare with a reference source chip IC 1 internal reference voltage, make one of a reference source chip IC 1 output and the directly proportional electric current of increase voltage of exporting, this electric current is held to the voltage ratio of PWM control module through opto-coupler chip U1 feed back input, and then reduces the duty ratio of switching tube (metal-oxide-semiconductor), thereby reduces output voltage, vice versa, realizes constant voltage and control function.
When if voltage output end Vo continues to raise; dividing potential drop in resistance R 14 increases; when the dividing potential drop in resistance R 3 and resistance R 14 rises to the puncture voltage of voltage-stabiliser tube ZD2; voltage-stabiliser tube ZD2 is switched on; the base stage of NPN type triode Q4 obtains bias current; and the collector current of NPN type triode Q4 rises; in opto-coupler chip U1, photodiode cathode electric current increases; thereby the voltage ratio that feeds back to PWM control module is held; and then reduce the duty ratio of switching tube; lower output voltage, realize the dual over-voltage protecting function to power supply and load.
A kind of novel trans exciting converter output overvoltage protection circuit above the utility model embodiment being provided is described in detail, applied specific case herein principle of the present utility model and execution mode are set forth, the explanation of above embodiment is just for helping to understand core concept of the present utility model; , for one of ordinary skill in the art, according to thought of the present utility model, all will change in specific embodiments and applications, in sum, this description should not be construed as restriction of the present utility model meanwhile.
Claims (4)
1. novel trans exciting converter output overvoltage protection circuit, comprise: PWM control module, metal-oxide-semiconductor, transformer and current-limiting resistance, voltage input end Vin+ is successively by transformer primary side coil, metal-oxide-semiconductor drain electrode and source electrode, current-limiting resistance connects equipment ground, the grid that PWM control module connects metal-oxide-semiconductor is used for controlling metal-oxide-semiconductor conducting or cut-off, transformer secondary coil is powered to voltage output end Vo through rectifier diode and output filtering module successively, it is characterized in that, also comprise: opto-coupler chip U1, NPN type triode Q4 and a reference source chip IC 1, rectifier diode negative electrode connects photodiode anode in opto-coupler chip U1 through a voltage-stabiliser tube ZD1, described photodiode cathode connects the cathode connection terminal of a reference source chip IC 1, the anodic bonding power supply ground of a reference source chip IC 1, voltage output end Vo is successively through a resistance R 13, one resistance R 14 connects power supply ground, the base pressure of a reference source chip IC 1 arranges end and is connected on the tie point of resistance R 13 and resistance R 14, the output of output filtering module is successively through a voltage-stabiliser tube ZD2, one resistance R 12 is connected to the base stage of NPN type triode Q4, the collector electrode of NPN type triode Q4 connects described photodiode cathode, the emitter of NPN type triode Q4 connects power supply ground, in opto-coupler chip U1, the voltage ratio of the collector electrode of phototriode connection PWM control module is held, in opto-coupler chip U1, the emitter of phototriode connects equipment ground.
2. novel trans exciting converter output overvoltage protection circuit as claimed in claim 1, is characterized in that, described a reference source chip IC 1 adopts TL431 chip.
3. novel trans exciting converter output overvoltage protection circuit as claimed in claim 1, is characterized in that, also comprise one with the ancillary coil of transformer primary side coil coupling, ancillary coil is powered to PWM control module.
4. novel trans exciting converter output overvoltage protection circuit as claimed in claim 1, is characterized in that, the cathode connection terminal of a reference source chip IC 1 arranges end with base pressure and is connected a capacitor C 12.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320687667.4U CN203536942U (en) | 2013-11-01 | 2013-11-01 | A novel ring choke converter output overvoltage protection circuit |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201320687667.4U CN203536942U (en) | 2013-11-01 | 2013-11-01 | A novel ring choke converter output overvoltage protection circuit |
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| CN203536942U true CN203536942U (en) | 2014-04-09 |
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| CN201320687667.4U Expired - Lifetime CN203536942U (en) | 2013-11-01 | 2013-11-01 | A novel ring choke converter output overvoltage protection circuit |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105406700A (en) * | 2015-12-21 | 2016-03-16 | 中国科学院广州能源研究所 | Photovoltaic inverter bus capacitance pressure equalization and bus overvoltage protection control circuit and system |
| CN106300247A (en) * | 2015-06-05 | 2017-01-04 | 中兴通讯股份有限公司 | Voltage protection circuit and system |
| CN106645892A (en) * | 2016-09-09 | 2017-05-10 | 广东欧珀移动通信有限公司 | Over-voltage detection circuit |
| CN109274075A (en) * | 2018-11-22 | 2019-01-25 | 无锡全裕电子科技有限公司 | A kind of locking protection circuit of Switching Power Supply |
| CN109361382A (en) * | 2018-12-18 | 2019-02-19 | 天津瑞能电气有限公司 | A kind of field-effect tube driving circuit |
| CN109510468A (en) * | 2018-12-19 | 2019-03-22 | 奥克斯空调股份有限公司 | A kind of switching power circuit and air conditioner |
| CN110719022A (en) * | 2019-10-21 | 2020-01-21 | 珠海格力电器股份有限公司 | Sampling feedback circuit, sampling feedback method and inverter system |
| CN112003241A (en) * | 2020-07-14 | 2020-11-27 | 宁波安信数控技术有限公司 | Overcurrent and overvoltage protection circuit for switching power supply |
| CN112072903A (en) * | 2020-08-28 | 2020-12-11 | 珠海格力电器股份有限公司 | Load protection device and method of flyback transformer switching power supply and electrical equipment |
| WO2020260271A1 (en) * | 2019-06-26 | 2020-12-30 | Valeo Equipements Electriques Moteur | Electronic commutator |
| CN113922450A (en) * | 2021-10-13 | 2022-01-11 | 苏州贝克微电子有限公司 | Power supply circuit with low noise |
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2013
- 2013-11-01 CN CN201320687667.4U patent/CN203536942U/en not_active Expired - Lifetime
Cited By (17)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106300247A (en) * | 2015-06-05 | 2017-01-04 | 中兴通讯股份有限公司 | Voltage protection circuit and system |
| CN105406700A (en) * | 2015-12-21 | 2016-03-16 | 中国科学院广州能源研究所 | Photovoltaic inverter bus capacitance pressure equalization and bus overvoltage protection control circuit and system |
| CN106645892A (en) * | 2016-09-09 | 2017-05-10 | 广东欧珀移动通信有限公司 | Over-voltage detection circuit |
| CN106645892B (en) * | 2016-09-09 | 2020-01-14 | Oppo广东移动通信有限公司 | Overvoltage detection circuit |
| CN109274075A (en) * | 2018-11-22 | 2019-01-25 | 无锡全裕电子科技有限公司 | A kind of locking protection circuit of Switching Power Supply |
| CN109361382B (en) * | 2018-12-18 | 2024-01-23 | 天津瑞能电气有限公司 | Field effect transistor driving circuit |
| CN109361382A (en) * | 2018-12-18 | 2019-02-19 | 天津瑞能电气有限公司 | A kind of field-effect tube driving circuit |
| CN109510468A (en) * | 2018-12-19 | 2019-03-22 | 奥克斯空调股份有限公司 | A kind of switching power circuit and air conditioner |
| CN109510468B (en) * | 2018-12-19 | 2024-03-15 | 奥克斯空调股份有限公司 | Switching power supply circuit and air conditioner |
| WO2020260271A1 (en) * | 2019-06-26 | 2020-12-30 | Valeo Equipements Electriques Moteur | Electronic commutator |
| FR3098062A1 (en) * | 2019-06-26 | 2021-01-01 | Valeo Equipements Electriques Moteur | Electronic switch |
| CN110719022A (en) * | 2019-10-21 | 2020-01-21 | 珠海格力电器股份有限公司 | Sampling feedback circuit, sampling feedback method and inverter system |
| CN112003241A (en) * | 2020-07-14 | 2020-11-27 | 宁波安信数控技术有限公司 | Overcurrent and overvoltage protection circuit for switching power supply |
| CN112003241B (en) * | 2020-07-14 | 2022-11-11 | 宁波安信数控技术有限公司 | Overcurrent and overvoltage protection circuit for switching power supply |
| CN112072903A (en) * | 2020-08-28 | 2020-12-11 | 珠海格力电器股份有限公司 | Load protection device and method of flyback transformer switching power supply and electrical equipment |
| CN113922450B (en) * | 2021-10-13 | 2023-10-13 | 苏州贝克微电子股份有限公司 | Power supply circuit with low noise |
| CN113922450A (en) * | 2021-10-13 | 2022-01-11 | 苏州贝克微电子有限公司 | Power supply circuit with low noise |
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Granted publication date: 20140409 |