CN103872755A - Double power supply seamless switching circuit - Google Patents
Double power supply seamless switching circuit Download PDFInfo
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- CN103872755A CN103872755A CN201210550168.0A CN201210550168A CN103872755A CN 103872755 A CN103872755 A CN 103872755A CN 201210550168 A CN201210550168 A CN 201210550168A CN 103872755 A CN103872755 A CN 103872755A
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Abstract
The invention relates to a double power supply seamless switching circuit which comprises a main power supply P1, a spared power supply P2, two protection and filtering units and two diode voltage reduction and switching units, wherein the output of the main power supply P1 and the output of the spared power supply P2 respectively pass a protective tube F1 and a protective tube F2 and are connected with the input ends of the respective protection and filtering units, the output end of the protection and filtering unit of the main power supply P1 loop is connected with the diode voltage reduction and switching unit of the main power supply P1 loop, the output end of the protection and filtering unit of the spared power supply P2 loop is connected with the diode voltage reduction and switching unit of the spared power supply P2 loop, and the two diode voltage reduction and switching units form seamless switching power output. The double power supply seamless switching circuit can effectively resist rapid electrical transient pulse train interference and surge interference, and meanwhile, the spared power supply can be put into use automatically when the main power supply loses power within 30nS. The double power supply seamless switching circuit is environment-friendly, durable, high in efficiency, long in service life and high in safety.
Description
Technical field
The invention belongs to field of power supplies, especially a kind of duplicate supply seamless switching circuit.
Background technology
Along with scientific and technical progress, every profession and trade is more and more higher for the requirement of power supply reliability and stability, and a lot of occasions require to guarantee with two-way power supply the reliability of power supply.The two-way power-supply switching method in past, conventionally adopt the mode of double diode parallel connection, or the mode of relay switch, all there is certain drawback in these two kinds of modes, for the former, because two-way power supply is connected in parallel, in the time of the full electricity of standby battery, voltage can be higher than main power source, at this moment preferentially powering load of stand-by power supply, run counter to the main power source preferential principle of powering, but this kind of technical costs is lower, hardware circuit is realized convenient, so application is also more extensive in the smaller circuit of power consumption; For the mode of relay switch, the about 1K Ω of relay-coil resistance left and right, so relay switch mode power consumption is large, switching time is slower, and reed can produce electric spark while switching, can cause danger at Code in Hazardous Special Locations, but relay silver alloy contact resistance is little, and rated current is larger, the industry of some particular requirement also can be used.
Summary of the invention
The object of the invention is to overcome the deficiencies in the prior art, a kind of duplicate supply seamless switching circuit is provided.
The present invention solves its technical problem and takes following technical scheme to realize:
A kind of duplicate supply seamless switching circuit, comprise main power source P1, stand-by power supply P2, protect and filter unit for two, two diode step-downs and switch unit, the output of main power source P1 and stand-by power supply P2 is connected with protection and filter unit input separately after protective tube F2 through protective tube F1 respectively, the protection in main power source P1 loop and the output of filter unit are connected with diode step-down and the switch unit in main power source P1 loop, the protection in stand-by power supply P2 loop and the output of filter unit are connected with diode step-down and the switch unit in stand-by power supply P2 loop, two diode step-downs and switch unit form the electric energy output of seamless switching.
And, described two protections and filter unit full symmetric, and negative pole is altogether, two protections and filter unit circuit structure, parameter are identical.
And, the protection in described main power source P1 loop and filter unit comprise the diode D4 being serially connected in after protective tube F1, be connected in parallel on the Transient Suppression Diode TVS1 between output and the power cathode of diode D4, be connected to the transient suppression device RV1 between Transient Suppression Diode TVS1 positive pole and ground, be connected to the transient suppression device RV2 between Transient Suppression Diode TVS1 negative pole and ground, be connected in parallel on the common mode choke coil L1 at Transient Suppression Diode TVS1 two ends, be connected to the safety capacitor C 1 that resists electric fast-pulse group between common mode choke coil L1 positive output end and ground, be connected to the safety capacitor C 6 that common mode choke coil L1 negative output terminal resists electric fast-pulse group, be connected in parallel on respectively the filter capacitor C3 of common mode choke coil L1 output, C4, C5.
And, the diode step-down in described main power source P1 loop and switch unit comprise diode D3, the diode D_CHECK1 and the ground capacity C2 that are connected on successively protection and filter unit output cathode, node between diode D_CHECK1 and ground capacity C2 is the anodal VCC of power supply output, and the node between diode D3 and diode D_CHECK1 is connected with the diode step-down in stand-by power supply P2 loop and the fet gate G of switch unit; Comprise and being connected between protection and filter unit output cathode and ground by the power indicating circuit of connecting with resistance R 1 after light-emitting diode D1, D2 reverse parallel connection.
And, the diode step-down in described stand-by power supply P2 loop and switch unit comprise and be connected on successively protection and diode D8, rectifier diode D_vol_1, rectifier diode D_vol_3, rectifier diode D_vol_4, rectifier diode D_vol_2, field effect transistor and the ground capacity C2 of filter unit output cathode, and the node in the diode pressure unit in fet gate G and main power source P1 loop between diode D3 and diode D_check1 is connected; Comprise between the node and ground being connected between rectifier diode D_vol_4 and rectifier diode D_vol_2, by the power indicating circuit of connecting with resistance R 2 after light-emitting diode D5, D6 reverse parallel connection.
Advantage of the present invention and good effect are:
1, the surge protection in the present invention adopts the high-power Transient Suppression Diode of 1500W; maximum clamp voltage 36V; in the time that input power two ends are subject to transient state high energy impact events; it can be with 10 the speed of bearing 12 power second-times; the high impedance of its two interpolar is become to Low ESR; absorb up to kilowatt surge power; make two interpolar clampers in a predetermined value; effectively guaranteed the precision components in the load of rear end, this kind of design have that the response time is fast, transient power is large, leakage current is low, without the advantage such as damage limit, volume be small and exquisite.
2, the filtering in the present invention adopts common mode choke to realize, electronic circuit is the object of an electromagnetic interference in the process of work, also be an electromagnetic interference source simultaneously, we select the common mode choke of 4.7mH and the inductance of 56 μ H, want on the one hand the common mode electromagnetic interference on filtered signal line, inhibition itself is not sent electromagnetic interference to the external world again on the other hand, plays good EMI filter action.
3, seamless switching device of the present invention is realized by field effect transistor, and it belongs to voltage-controlled type semiconductor device, when for conducting, has 10
8the input impedance of Ω, the resistance very little (only 0.02 Ω) during simultaneously due to its conducting, so power consumption is very little, seamless switching part is a kind of perfect performance, the high technical scheme of safe and reliable, easy to operate, intelligent degree.
Accompanying drawing explanation
Fig. 1 is circuit block diagram of the present invention;
Fig. 2 is surge protection of the present invention, filter unit circuit diagram;
Fig. 3 is surge protection of the present invention, filter unit input, output waveform figure;
Fig. 4 is diode step-down of the present invention, seamless switching element circuit figure;
Fig. 5 is diode step-down of the present invention, the input of seamless switching unit, output waveform figure;
Fig. 6 is that the present invention inputs in the time that duplicate supply is working properly, output waveform figure;
Fig. 7 is that the present invention inputs in the time of main power source P1 dead electricity, output waveform figure;
Fig. 8 is input, the output waveform figure that the present invention resists electromagnetic interference.
Embodiment
Below in conjunction with accompanying drawing, the embodiment of the present invention being further described: embodiment of the present invention is illustrative, is not determinate, can not be using this embodiment as limiting the scope of the present invention.
A kind of duplicate supply seamless switching circuit, as shown in Figure 1, comprise main power source P1, stand-by power supply P2, protect and filter unit for two, two diode step-downs and switch unit, the output of main power source P1 and stand-by power supply P2 is connected with protection and filter unit input separately after protective tube F2 through protective tube F1 respectively, the protection in main power source P1 loop and the output of filter unit are connected with diode step-down and the switch unit in main power source P1 loop, the protection in stand-by power supply P2 loop and the output of filter unit are connected with diode step-down and the switch unit in stand-by power supply P2 loop, two diode step-downs and switch unit form the electric energy output of seamless switching
In specific embodiment of the invention, described main power source P1 is 24V, and stand-by power supply P2 adopts the standby battery power supply of voltage range at 20V～28V.
In specific embodiment of the invention, as shown in Figure 2, described protective tube adopts the plate glass insurance pipe F1 that parameter is 5A/250V.
In circuit of the present invention due to main power source P1 loop and the protection in stand-by power supply P2 loop and the symmetry of filter unit; so only protection and the filter unit in main power source P1 loop are elaborated; stand-by power supply P2 loop is identical with main power source P1 loop structure, in circuit device parameters select also identical.
In specific embodiment of the invention, as shown in Figure 2, the protection in described main power source P1 loop and filter unit comprise the diode D4 being serially connected in after protective tube F1, be connected in parallel on the Transient Suppression Diode TVS1 between output and the power cathode of diode D4, be connected to the transient suppression device RV1 between Transient Suppression Diode TVS1 positive pole and ground, be connected to the transient suppression device RV2 between Transient Suppression Diode TVS1 negative pole and ground, be connected in parallel on the common mode choke coil L1 at Transient Suppression Diode TVS1 two ends, be connected to the safety capacitor C 1 that resists electric fast-pulse group between common mode choke coil L1 positive output end and ground, be connected to the safety capacitor C 6 that common mode choke coil L1 negative output terminal resists electric fast-pulse group, be connected in parallel on respectively the filter capacitor C3 of common mode choke coil L1 output, C4, C5.
Wherein, the rated current of described diode D4 is 3A.
Wherein, the starting resistor of described Transient Suppression Diode TVS1 is 36V.
Wherein, described common mode choke coil L1 is 4.7mH, and described inductance coil L2 is 56 μ H.
Wherein, RV1, RV2 transient suppression device have good inhibitory action for the 1KV voltage between line ground, and in like manner, safety capacitor C 1, C6 can have resistancing action to the electric fast-pulse group of 5KHZ, peak value 2KV.
Known according to the computing formula XL=2 π fL of induction reactance, inductive reactance xl and inductance value L are directly proportional, and frequency f is also directly proportional, and for the burst of pulses of 2.5KHZ～5KHZ, it is more reasonable that we choose common mode choke and the 56 μ H inductance coils of 4.7mH.
What power filter used is jumbo electrochemical capacitor, to reduce galvanic degree of fluctuation with removing power frequency waveform (50Hz-100Hz) in direct current, play smooth waveform, and the capacity of decoupling capacitor is very little, be generally 0.01-0.1uF, it is the high-frequency harmonic composition producing in the time working for filtering circuit, it should be noted that, jumbo electrochemical capacitor cannot filtering high-frequency harmonic composition, so filter unit part adopts the general ripe framework of the little electric capacity of large Capacitance parallel connection, through software emulation and hard ware measure repeatedly, choose 470uF/50V electrochemical capacitor herein, the burst of pulses best results of the nonpolarity ceramic disc capacitor filtering 5KHZ in parallel of 10uF/50V tantalum electric capacity and 0.1uF/50V.
Fig. 3 is for protection and filter unit is inputted, output waveform figure; be input as the frequency 5KHZ of function generator generation, the sinusoidal wave pulse group of amplitude 10Vp; by oscillographic passage 1, we can clearly see the oscillogram of input; after surge protection, filter unit, become the direct voltage of the 13.0V that output voltage is constant, waveform is level and smooth; utilize and in universal instrument measuring circuit, have 6.3mA electric current; visible after said units; entirety pressure drop amplitude is little; simultaneously; main power source P1 indicator light D2 green light, proves that output is normal.
In specific embodiment of the invention, as shown in Fig. 1 or 4, the protection in main power source P1 loop and the negative pole of filter unit and the protection in stand-by power supply P2 loop and the negative pole of filter unit are altogether.
In specific embodiment of the invention, as shown in Fig. 1 or 4, the diode step-down in main power source P1 loop and switch unit comprise the diode D3 that is connected on successively protection and filter unit output cathode, diode D_CHECK1 and ground capacity C2, node between diode D_CHECK1 and ground capacity C2 is the anodal VCC of power supply output, node between diode D3 and diode D_CHECK1 is connected with the diode step-down in stand-by power supply P2 loop and the fet gate G of switch unit, comprise and being connected between protection and filter unit output cathode and ground by light-emitting diode D1, the power indicating circuit of connecting with resistance R 1 after D2 reverse parallel connection.
The diode step-down in stand-by power supply P2 loop and switch unit comprise the diode D8 that is connected on successively protection and filter unit output cathode, rectifier diode D_vol_1, rectifier diode D_vol_3, rectifier diode D_vol_4, rectifier diode D_vol_2, field effect transistor and ground capacity C2, node in the diode pressure unit in fet gate G and main power source P1 loop between diode D3 and diode D_check1 is connected, comprise between the node and ground being connected between rectifier diode D_vol_4 and rectifier diode D_vol_2, by light-emitting diode D5, the power indicating circuit of connecting with resistance R 2 after D6 reverse parallel connection.
Wherein, the parameter of described diode D8, rectifier diode D_vol_1, rectifier diode D_vol_3, rectifier diode D_vol_4, rectifier diode D_vol_2 is pressure drop 0.7V, rated current 3A.
When stand-by power supply P2 voltage is during greater than or equal to main power source P1 voltage, stand-by power supply P2 crosses 4 rectifier diodes (not adopting Schottky diode herein) than main power source P1 multithread, calculate according to each diode drop 0.7V, 2.8V when voltage that 4 rectifier diodes are got, because the cut-in voltage of field effect transistor in this circuit is 4.0V, be that the source S utmost point is than the conducting of the high 4.0V field effect transistor ability of grid G, combined circuit figure is known, the in the situation that of main power source P124V, if we can extrapolate want to allow field effect transistor conducting stand-by power supply P2 at least to reach 30.8V(24V+4V+2.8V), under normal circumstances, when storage battery is full of electricity, voltage is no more than 30V, when so this kind of design can guarantee that double loop power supply is normal, the preferential main power source P1 that selects powers.
Fig. 5 provides diode step-down and switch unit circuit waveform figure, the sine wave (shown in channel oscilloscope 1) of input main power source P1 selected frequency 1KHZ, amplitude 15Vp, stand-by power supply P2 selects the direct current of 30V to carry out imitated storage battery to be full of electric state (shown in channel oscilloscope 2), we can see that the waveform two-way power supply is by step-down, switch unit is level and smooth from oscillographic passage 4, burr is less, be desirable output state, the impulse train interference that can make up main power source P1 in the stable output of stand-by power supply P2 has also been described simultaneously.
Fig. 6 is the circuit waveform figure of duplicate supply time working properly, we on main power source P1 and stand-by power supply P2 port, connect respectively universal instrument measure electric current, reading by twice universal instrument is known, in the time that main power source P1 and stand-by power supply P2 power with 24V simultaneously, main power source P1 can preferential powering load, and the electric current of stand-by power supply P2 output is very little, the 9.07mA electric current of lighting stand-by power supply P2 indicator light D5 is only provided, drive whole electric currents of load all to carry out automatic power supply P1(main power source P1 universal instrument reading is 117.95mA simultaneously), can find out that by the waveform of channel oscilloscope 4 final output voltage is smoothly stable.
Fall for main power source P1 moment, the situation of power down, Fig. 7 has provided circuit waveform figure, passage 1 show main power source P1 now voltage be 0V, now main power source P1 status indicator lamp D1, D2 does not work, we can determine it is now the situation of main power source P1 dead electricity, by channel oscilloscope 2 reading, known stand-by power supply P2 is working properly, and indicator of the power supply status D5 is luminous, now known by being connected on the universal instrument current indication of power port, the required 105mA electric current of load is all to be provided by stand-by power supply P2, can find out by the waveform state in channel oscilloscope 4, power supply output is normal, waveform is level and smooth, without burr.Fig. 8 is the oscillogram of this scheme opposing electromagnetic interference, in the drawings, we can find out that having made frequency into as the power supply of input is 5KHZ, amplitude is the impulse wave input of 18Vp, known by being connected in parallel on the universal instrument reading of power port, the interference of burst of pulses to power supply and the priority of power supply have nothing to do, because the filter circuit part of main power source P1 and stand-by power supply P2 is basic identical, and the harmonic components of burst of pulses exactly consumes in filter circuit part, this point can be found (passage 2 is protection and filter unit output waveform) by the contrast of channel oscilloscope 1 and passage 2, the oscillogram of channel oscilloscope 4 is all a level and smooth straight line, so, this technical scheme can arrive ideal effect.
Claims (5)
1. a duplicate supply seamless switching circuit, it is characterized in that: comprise main power source P1, stand-by power supply P2, protect and filter unit for two, two diode step-downs and switch unit, the output of main power source P1 and stand-by power supply P2 is connected with protection and filter unit input separately after protective tube F2 through protective tube F1 respectively, the protection in main power source P1 loop and the output of filter unit are connected with diode step-down and the switch unit in main power source P1 loop, the protection in stand-by power supply P2 loop and the output of filter unit are connected with diode step-down and the switch unit in stand-by power supply P2 loop, two diode step-downs and switch unit form the electric energy output of seamless switching.
2. duplicate supply seamless switching circuit according to claim 1, is characterized in that: described two protections and filter unit full symmetric, and negative pole is altogether, and two protections and filter unit circuit structure, parameter are identical.
3. duplicate supply seamless switching circuit according to claim 1, it is characterized in that: the protection in described main power source P1 loop and filter unit comprise the diode D4 being serially connected in after protective tube F1, be connected in parallel on the Transient Suppression Diode TVS1 between output and the power cathode of diode D4, be connected to the transient suppression device RV1 between Transient Suppression Diode TVS1 positive pole and casing ground, be connected to the transient suppression device RV2 between Transient Suppression Diode TVS1 negative pole and casing ground, be connected in parallel on the common mode choke coil L1 at Transient Suppression Diode TVS1 two ends, be connected to the safety capacitor C 1 that suppresses electric fast-pulse group between common mode choke coil L1 positive output end and ground, be connected to the safety capacitor C 6 that common mode choke coil L1 negative output terminal suppresses electric fast-pulse group, be connected in parallel on respectively the filter capacitor C3 of common mode choke coil L1 output, C4, C5.
4. duplicate supply seamless switching circuit according to claim 1, it is characterized in that: the diode step-down in described main power source P1 loop and switch unit comprise diode D3, the diode D_CHECK1 and the ground capacity C2 that are connected on successively protection and filter unit output cathode, node between diode D_CHECK1 and ground capacity C2 is the anodal VCC of power supply output, and the node between diode D3 and diode D_CHECK1 is connected with the diode step-down in stand-by power supply P2 loop and the fet gate G of switch unit; Comprise and being connected between protection and filter unit output cathode and ground by the power indicating circuit of connecting with resistance R 1 after light-emitting diode D1, D2 reverse parallel connection.
5. duplicate supply seamless switching circuit according to claim 1, it is characterized in that: the diode step-down in described stand-by power supply P2 loop and switch unit comprise and be connected on successively protection and diode D8, rectifier diode D_vol_1, rectifier diode D_vol_3, rectifier diode D_vol_4, rectifier diode D_vol_2, field effect transistor and the ground capacity C2 of filter unit output cathode, the node in the diode pressure unit in fet gate G and main power source P1 loop between diode D3 and diode D_check1 is connected; Comprise between the node and ground being connected between rectifier diode D_vol_4 and rectifier diode D_vol_2, by the power indicating circuit of connecting with resistance R 2 after light-emitting diode D5, D6 reverse parallel connection.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104578287A (en) * | 2014-12-30 | 2015-04-29 | 吴文武 | Charger for direct current power supply |
| CN105486253A (en) * | 2015-12-20 | 2016-04-13 | 新余钢铁集团有限公司 | Wiring structure of thickness meter high-voltage radiation source power supply |
| CN105591454A (en) * | 2014-10-20 | 2016-05-18 | 中兴通讯股份有限公司 | Power supply processing method, device and power source |
| CN105990900A (en) * | 2015-01-30 | 2016-10-05 | 明瑞电子(成都)有限公司 | Redundancy power control circuit and redundancy power supplying system using same |
| CN107623373A (en) * | 2016-07-14 | 2018-01-23 | 深圳光启空间技术有限公司 | Power supply switch circuit and power supply, unmanned plane and its master board |
| CN109510953A (en) * | 2018-11-29 | 2019-03-22 | 中国航空工业集团公司沈阳飞机设计研究所 | A kind of S separation vision signal is converted to the conversion circuit of composite video signal |
| CN110993388A (en) * | 2019-11-29 | 2020-04-10 | 施耐德万高（天津）电气设备有限公司 | Electromagnet driving circuit and method special for automatic transfer switch |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201405807Y (en) * | 2009-04-15 | 2010-02-17 | 同济大学 | Power supply circuit for whole vehicle controller of hybrid power bus |
| CN101707393A (en) * | 2009-11-18 | 2010-05-12 | 太仓市同维电子有限公司 | Automatic switching circuit of power supply |
| CN101752898A (en) * | 2009-12-30 | 2010-06-23 | 上海天健电气有限公司 | Controller for controlling double-power circuit |
| EP2579425A1 (en) * | 2010-05-25 | 2013-04-10 | Hytera Communications Corp., Ltd. | Smooth switching device and method for double power supplies |
-
2012
- 2012-12-17 CN CN201210550168.0A patent/CN103872755A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201405807Y (en) * | 2009-04-15 | 2010-02-17 | 同济大学 | Power supply circuit for whole vehicle controller of hybrid power bus |
| CN101707393A (en) * | 2009-11-18 | 2010-05-12 | 太仓市同维电子有限公司 | Automatic switching circuit of power supply |
| CN101752898A (en) * | 2009-12-30 | 2010-06-23 | 上海天健电气有限公司 | Controller for controlling double-power circuit |
| EP2579425A1 (en) * | 2010-05-25 | 2013-04-10 | Hytera Communications Corp., Ltd. | Smooth switching device and method for double power supplies |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105591454A (en) * | 2014-10-20 | 2016-05-18 | 中兴通讯股份有限公司 | Power supply processing method, device and power source |
| CN104578287A (en) * | 2014-12-30 | 2015-04-29 | 吴文武 | Charger for direct current power supply |
| CN105990900A (en) * | 2015-01-30 | 2016-10-05 | 明瑞电子(成都)有限公司 | Redundancy power control circuit and redundancy power supplying system using same |
| CN105990900B (en) * | 2015-01-30 | 2018-08-17 | 明瑞电子(成都)有限公司 | Stand-by power supply control circuit and use its stand-by power supply supply system |
| US10418848B2 (en) | 2015-01-30 | 2019-09-17 | Alpha Networks Inc. | Redundancy power supply system and power-switching control thereof |
| CN105486253A (en) * | 2015-12-20 | 2016-04-13 | 新余钢铁集团有限公司 | Wiring structure of thickness meter high-voltage radiation source power supply |
| CN107623373A (en) * | 2016-07-14 | 2018-01-23 | 深圳光启空间技术有限公司 | Power supply switch circuit and power supply, unmanned plane and its master board |
| CN109510953A (en) * | 2018-11-29 | 2019-03-22 | 中国航空工业集团公司沈阳飞机设计研究所 | A kind of S separation vision signal is converted to the conversion circuit of composite video signal |
| CN110993388A (en) * | 2019-11-29 | 2020-04-10 | 施耐德万高（天津）电气设备有限公司 | Electromagnet driving circuit and method special for automatic transfer switch |
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Application publication date: 20140618 |