CN217984652U

CN217984652U - Automatic power supply switching circuit

Info

Publication number: CN217984652U
Application number: CN202220713976.3U
Authority: CN
Inventors: 张超; 朱振广; 杨媛媛
Original assignee: Beijing U Precision Tech Co Ltd
Current assignee: Beijing Youwei Precision Measurement And Control Technology Research Co ltd; Beijing U Precision Tech Co Ltd
Priority date: 2022-03-29
Filing date: 2022-03-29
Publication date: 2022-12-06
Anticipated expiration: 2032-03-29

Abstract

The utility model provides a power automatic switch-over circuit relates to power switching technical field, include: the power supply comprises a main power supply module, an auxiliary power supply module, a first triode, a second triode, a third triode, a first MOS (metal oxide semiconductor) tube and a second MOS tube; the main power supply module is electrically connected to a load through a first MOS tube; the first triode is electrically connected with the first MOS tube and used for controlling the on-off of the first MOS tube; the auxiliary power supply module is electrically connected to a load through a second MOS tube; the second triode is electrically connected with the second MOS tube and used for controlling the on-off of the second MOS tube; the third triode is electrically connected with the second triode and used for controlling the on-off of the second triode; the first triode is also electrically connected to the main power supply module; the second triode is also electrically connected to the auxiliary power supply module; the third triode is also electrically connected to the main power supply module and the auxiliary power supply module respectively. The utility model provides a technical scheme can realize the uninterrupted switching between main, the secondary power supply to guarantee the normal work of equipment.

Description

Automatic power supply switching circuit

Technical Field

The utility model relates to a power switches technical field, relates to a power automatic switch-over circuit especially.

Background

In order to ensure the uninterrupted operation of the equipment, the equipment is generally provided with two power supplies, namely a main power supply and a secondary power supply. When the power supply is in normal work, the main power supply is mainly input for power supply, and when the main power supply is accidentally powered off, the power supply is automatically switched to the auxiliary power supply.

The conventional power supply switching method is mostly realized by a relay operation. However, the relay as a switch has a large volume, a low operating frequency, a slow switching speed, and contacts, which may generate electromagnetic interference, and all the above disadvantages may affect the normal operation of the device, i.e. the prior art cannot realize uninterrupted switching between the main power supply and the auxiliary power supply.

SUMMERY OF THE UTILITY MODEL

To solve the problems in the prior art, the application provides an automatic power supply switching circuit which can realize uninterrupted switching between a main power supply and an auxiliary power supply, so that normal work of equipment is ensured.

In order to achieve the above purpose, the technical scheme of the utility model is realized as follows:

an automatic power switching circuit comprising: the power supply comprises a main power supply module, an auxiliary power supply module, a first triode, a second triode, a third triode, a first MOS (metal oxide semiconductor) tube and a second MOS tube; the main power supply module is electrically connected to a load through the first MOS tube; the first triode is electrically connected with the first MOS tube and is used for controlling the on-off of the first MOS tube; the auxiliary power supply module is electrically connected to a load through the second MOS tube; the second triode is electrically connected with the second MOS tube and used for controlling the on-off of the second MOS tube; the third triode is electrically connected with the second triode and used for controlling the on-off of the second triode; the first triode is also electrically connected to the main power supply module; the second triode is also electrically connected to the auxiliary power supply module; the third triode is also electrically connected to the main power supply module and the auxiliary power supply module respectively.

Preferably, the first triode, the second triode and the third triode are all NPN-type triodes; the first MOS tube and the second MOS tube are both PMOS tubes.

Preferably, the source of the first MOS transistor is connected to the main power supply module, the drain of the first MOS transistor is connected to the load, and the gate of the first MOS transistor is connected to the main power supply module through a resistor R1; the collector electrode of the first triode is connected with the grid electrode of the first MOS tube through a resistor R2, the base electrode of the first triode is connected with the main power supply module through a resistor R3, and the emitting electrode of the first triode is grounded.

Preferably, the number of the first MOS transistors is at least one, and the first MOS transistors are connected in parallel.

Preferably, the source of the second MOS transistor is connected to the secondary power supply module, the drain of the second MOS transistor is connected to the load, and the gate of the second MOS transistor is connected to the secondary power supply module through a resistor R4; the collector electrode of the second triode is connected with the grid electrode of the second MOS tube through a resistor R5, the collector electrode of the second triode is also connected to the auxiliary power supply module through a resistor R6, the base electrode of the second triode is connected with the collector electrode of the third triode through a resistor R7, and the emitter electrode of the second triode is grounded; the collector of the third triode is also connected to the auxiliary power supply module through a resistor R8, and the emitter of the third triode is grounded; the base electrode of the third triode is connected with one end of a resistor R9, the other end of the resistor R9 is respectively connected with one end of a resistor R10 and one end of a resistor R11, the other end of the resistor R10 is connected to the main power supply module, and the other end of the resistor R11 is grounded.

Further, still include: a bypass capacitor; one end of the bypass capacitor is connected with the base electrode of the second triode, and the other end of the bypass capacitor is grounded.

Preferably, the number of the second MOS transistors is at least one, and the second MOS transistors are connected in parallel.

Further, still include: a first diode and a second diode for preventing current from flowing backward; the first diode is arranged between the first MOS tube and the load; the second diode is arranged between the second MOS tube and the load.

Preferably, the first diodes are connected in parallel; the second diode is at least one, and the second diodes are connected in parallel.

Further, fuses are arranged between the first diode and the load and between the second diode and the load.

Further, still include: at least one electrolytic capacitor connected in parallel with each other; the anode of the electrolytic capacitor is connected with the load, and the cathode of the electrolytic capacitor is grounded.

The embodiment of the utility model provides a power automatic switching circuit has set up main power module, secondary power module, first triode, second triode, third triode, first MOS pipe and second MOS pipe, and, main power module is through the electric connection of first MOS pipe to the load, first triode and first MOS pipe electric connection, are used for controlling the break-make of first MOS pipe; the auxiliary power supply module is electrically connected to a load through a second MOS tube, and the second triode is electrically connected with the second MOS tube and used for controlling the on-off of the second MOS tube; the third triode is electrically connected with the second triode and used for controlling the on-off of the second triode; the first triode is also electrically connected to the main power supply module, the second triode is also electrically connected to the auxiliary power supply module, and the third triode is also electrically connected to the main power supply module and the auxiliary power supply module respectively. It can be seen that the utility model provides a technical scheme adopts the active device as change over switch to reach the purpose of circuit break-make, and then accomplish the switching of main, auxiliary power supply. And active device compares with the relay, and switching speed is faster, operating frequency is higher, and contactless, can not produce electromagnetic interference for at the in-process that main, auxiliary power switched, the equipment of working is not switched by the power and is influenced, promptly, the utility model provides a technical scheme can realize the uninterrupted switching between main, auxiliary power, thereby guarantees the normal work of equipment.

Drawings

The scope of the present disclosure may be better understood by reading the following detailed description of exemplary embodiments in conjunction with the accompanying drawings. Wherein the included drawings are:

fig. 1 is a schematic circuit diagram of an embodiment of the present invention;

fig. 2 is a schematic diagram of a main power circuit in an embodiment of the present invention;

FIG. 3 is a schematic diagram of an embodiment of the present invention;

fig. 4 is a general diagram of switching between the primary power supply and the secondary power supply in the embodiment of the present invention.

Detailed Description

In order to make the purpose, technical solution and advantages of the present invention clearer, the following will be described in detail with reference to the accompanying drawings and embodiments, thereby to how to apply the technical means to solve the technical problem, and to achieve the technical effect of the realization process can be fully understood and implemented.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore the scope of the present invention is not limited by the specific embodiments disclosed below.

Can uninterruptedly provide the power for the equipment in work when guaranteeing main, secondary power module automatic switch-over, the utility model relates to a power automatic switch-over circuit when judging that main power module appears unusually, can the automatic switch-over to the power supply of secondary power module.

Based on the above thought, the embodiment of the utility model provides a power automatic switching circuit is provided, as shown in fig. 1, this circuit includes: the power supply comprises a main power supply module, an auxiliary power supply module, a first triode, a second triode, a third triode, a first MOS (metal oxide semiconductor) tube and a second MOS tube; the main power supply module is electrically connected to a load through the first MOS tube; the first triode is electrically connected with the first MOS tube and is used for controlling the on-off of the first MOS tube; the auxiliary power supply module is electrically connected to a load through the second MOS tube; the second triode is electrically connected with the second MOS tube and used for controlling the on-off of the second MOS tube; the third triode is electrically connected with the second triode and is used for controlling the on-off of the second triode; the first triode is also electrically connected to the main power supply module; the second triode is also electrically connected to the auxiliary power supply module; the third triode is also electrically connected to the main power supply module and the auxiliary power supply module respectively.

Further, the circuit described in this embodiment further includes: a first diode and a second diode for preventing current from flowing backward; the first diode is arranged between the first MOS tube and the load; the second diode is arranged between the second MOS tube and the load. In this embodiment, the first diode is at least one, and the first diodes are connected in parallel; the second diode is connected in parallel, so that the technical effect of more effectively preventing the current from flowing backwards is achieved.

The power supply module, the first triode and the first MOS tube are electrically connected to form a power supply circuit; the main power supply module, the auxiliary power supply module, the second triode, the third triode and the second MOS tube are electrically connected to form an auxiliary power supply circuit.

In this embodiment, the first triode, the second triode and the third triode are all NPN-type triodes; the first MOS tube and the second MOS tube are both PMOS tubes.

In practical application, the first triode, the second triode and the third triode can be NPN type triodes with the model number of S9013LT 1; the first MOS tube and the second MOS tube can adopt PMOS tubes with the model number of MJD 127.

The main power circuit in the present embodiment is electrically connected in the following manner: the source electrode of the first MOS tube is connected to the main power supply module, the drain electrode of the first MOS tube is connected to the load, and the grid electrode of the first MOS tube is connected to the main power supply module through a resistor R1; the collector electrode of the first triode is connected with the grid electrode of the first MOS tube through a resistor R2, the base electrode of the first triode is connected with the main power supply module through a resistor R3, and the emitting electrode of the first triode is grounded.

In order to reduce the loss caused by the internal resistance of the first MOS transistor, in this embodiment, at least one of the first MOS transistors is connected in parallel.

In order to prevent the current from flowing backward, a diode is further added to the output terminal of the main power circuit in this embodiment, that is, the circuit in this embodiment further includes: a first diode; the anode of the first diode is connected with the drain of the first MOS tube, and the cathode of the first diode is connected with the load.

In this embodiment, the first diode is connected in parallel.

Specifically, as shown in fig. 2, the main power module in this embodiment is 24V, and is denoted by 24V-MASTER in fig. 2. Q9, Q10, Q11, and Q12 are the first MOS transistors, Q13 is the first triode, and D6, D7, and D8 are the first diodes. Sources of Q9, Q10, Q11 and Q12 are directly connected to the main power supply module, gates of the Q9, Q10, Q11 and Q12 are connected to the main power supply module through resistors R1, and drains of the Q9, Q10, Q11 and Q12 are connected to a load through D6, D7 and D8 which are connected in parallel. The collector of Q13 is connected to the gates of Q9, Q10, Q11 and Q12 via a resistor R2, the base of Q13 is connected to the main power module via a resistor R3, and the emitter of Q13 is grounded. The drains of Q9, Q10, Q11, and Q12 are connected to the anodes of D6, D7, and D8, and the cathodes of D6, D7, and D8 are connected to the load.

The secondary power supply circuit in this embodiment is electrically connected in the following manner: the source electrode of the second MOS tube is connected to the auxiliary power supply module, the drain electrode of the second MOS tube is connected to the load, and the grid electrode of the second MOS tube is connected to the auxiliary power supply module through a resistor R4; the collector electrode of the second triode is connected with the grid electrode of the second MOS tube through a resistor R5, the collector electrode of the second triode is also connected to the auxiliary power supply module through a resistor R6, the base electrode of the second triode is connected with the collector electrode of the third triode through a resistor R7, and the emitter electrode of the second triode is grounded; the collector of the third triode is also connected to the auxiliary power supply module through a resistor R8, and the emitter of the third triode is grounded; the base electrode of the third triode is connected with one end of a resistor R9, the other end of the resistor R9 is respectively connected with one end of a resistor R10 and one end of a resistor R11, the other end of the resistor R10 is connected to the main power supply module, and the other end of the resistor R11 is grounded.

Further, in order to achieve the technical effects of filtering, decoupling, and the like, the circuit described in this embodiment further includes: a bypass capacitor; one end of the bypass capacitor is connected with the base electrode of the second triode, and the other end of the bypass capacitor is grounded.

In order to reduce the loss caused by the internal resistance of the second MOS transistors, in this embodiment, at least one of the second MOS transistors is connected in parallel.

In order to prevent the current from flowing backward, a diode is further added to the output terminal of the secondary power supply circuit in this embodiment, that is, the circuit described in this embodiment further includes: a second diode; the anode of the second diode is connected with the drain of the second MOS tube, and the cathode of the second diode is connected with the load.

In this embodiment, the second diode is connected in parallel.

Specifically, as shown in fig. 3, the primary power supply module and the secondary power supply module in this embodiment are both 24V, and are respectively represented by 24V-MASTER and 24V-SLAVE in fig. 3. Q5, Q6, Q7, Q8 are the second MOS transistors, Q3 is the second triode, Q4 is the third triode, and D3, D4, D5 are the first diodes. Sources of Q5, Q6, Q7 and Q8 are directly connected to the auxiliary power supply module, gates of the Q5, the Q6, the Q7 and the Q8 are connected to the auxiliary power supply module through resistors R4, and drains of the Q5, the Q7 and the Q8 are connected to a load through D3, D4 and D5 which are connected in parallel. Wherein, the drains of Q5, Q6, Q7 and Q8 are connected with the anodes of D3, D4 and D5, and the cathodes of D3, D4 and D5 are connected with the load.

The collector of Q3 is connected with the grids of Q5, Q6, Q7 and Q8 through a resistor R5, the collector of Q3 is also connected with the auxiliary power supply module through a resistor R6, the base of Q3 is connected with the collector of Q4 through a resistor R7, and the emitter of Q3 is grounded; one end of a bypass capacitor C10 is connected with the base electrode of the Q3, and the other end of the bypass capacitor C10 is grounded; the collector of the Q4 is also connected to the auxiliary power supply module through a resistor R8, and the emitter of the Q4 is grounded; the base electrode of the Q4 is connected with one end of a resistor R9, the other end of the resistor R9 is respectively connected with one end of a resistor R10 and one end of a resistor R11, the other end of the resistor R10 is connected to the main power supply module, and the other end of the resistor R11 is grounded.

In order to ensure the safety of the circuit, in this embodiment, fuses are further disposed between the first diode and the load and between the second diode and the load.

Further, in order to achieve the technical effects of filtering, decoupling, and the like, the circuit described in this embodiment further includes: at least one electrolytic capacitor connected in parallel with each other; the anode of the electrolytic capacitor is connected with the load, and the cathode of the electrolytic capacitor is grounded.

Specifically, as shown in fig. 4, F5 and F6 are the fuses, and CD1, CD2, CD3, CD4, and CD5 are the electrolytic capacitors. Fuse F5 and fuse F6 are connected in parallel, and the negative pole of D3 ~ D8 is connected to one end of fuse, and the load is connected to the other end of fuse. The positive electrodes of CD 1-CD 5 are connected with a load, and the negative electrodes of CD 1-CD 5 are grounded.

The working principle of the circuit is explained in detail in the following with reference to fig. 4:

when the main power supply module exists, no matter whether the auxiliary power supply module exists, the base electrode of a triode Q13 of the main power supply circuit is in a high level, a collector electrode and an emitter electrode are conducted and grounded, R2 is 0V, the grid electrodes of first MOS tubes Q9, Q10, Q11 and Q12 of the main power supply circuit are controlled to be 0V, the source electrode and the drain electrode of the first MOS tubes are in a conducting state, the first MOS tubes are output after passing through first diodes (also called as first anti-reverse diodes) D6, D7 and D8, the main power supply circuit is conducted, and a 24V power supply is provided for a load; at this time, the base of the transistor Q4 in the secondary power supply circuit is at a high level, the collector and the emitter of the transistor Q4 are conducted and grounded, so that the base of the transistor Q3 is at a low level, the collector and the emitter of the transistor Q3 are in an off state, the gates of the second MOS transistors Q5, Q6, Q7, and Q8 in the secondary power supply circuit are controlled to be 24V, the sources and the drains are in an off state, the second diodes (also referred to as second anti-reverse diodes) D3, D4, and D5 prevent the main power supply from inputting, and the secondary power supply circuit is off.

When the main power supply module does not exist and the auxiliary power supply module exists, the base electrode of a triode Q4 in the auxiliary power supply circuit is in a low level, a collector electrode and an emitter electrode are cut off, the base electrode of the triode Q3 is 24V, the collector electrode and the emitter electrode are conducted and grounded, the grid electrodes of MOS (metal oxide semiconductor) tubes Q5, Q6, Q7 and Q8 in the auxiliary power supply circuit are controlled to be 0V, the source electrode and the drain electrode are in a conducting state, and the auxiliary power supply circuit is conducted; the base electrode of a triode Q13 in the main power supply circuit is in low level, the collector electrode and the emitter electrode are cut off, R2 is 24V, the grid electrodes of MOS transistors Q9, Q10, Q11 and Q12 in the main power supply circuit are controlled to be 24V, the source electrode and the drain electrode are in cut-off states, and no voltage is input into the main power supply circuit.

As can be seen from the above working principle, in this embodiment, when the main power supply module exists, no matter whether the auxiliary power supply module exists, the transistor Q13 in the main power supply circuit is in a conducting state, and the MOS transistors Q9, Q10, Q11, and Q12 in the main power supply circuit are controlled to be conducting, so that the main power supply circuit is conducting; the triode Q4 in the auxiliary power supply circuit is in a conducting state, the triode Q3 is in a cut-off state, the triode Q3 controls MOS (metal oxide semiconductor) tubes Q5, Q6, Q7 and Q8 in the auxiliary power supply circuit to be cut off, and the auxiliary power supply circuit is cut off. At this time, the power of the apparatus is supplied by the main power supply module. When the main power supply module does not exist and the auxiliary power supply module exists, the triode Q4 in the auxiliary power supply circuit is in a cut-off state, the triode Q3 is in a conducting state, the triode Q3 controls the MOS (metal oxide semiconductor) tubes Q5, Q6, Q7 and Q8 in the auxiliary power supply circuit to be conducted, the auxiliary power supply circuit is conducted, and the main power supply circuit does not have voltage input. At this time, the power of the device is supplied by the sub power module.

The embodiment of the utility model provides a power automatic switching circuit has set up main power module, secondary power module, first triode, second triode, third triode, first MOS pipe and second MOS pipe, and, main power module is through the electric connection of first MOS pipe to the load, first triode and first MOS pipe electric connection, are used for controlling the break-make of first MOS pipe; the auxiliary power supply module is electrically connected to a load through a second MOS tube, and the second triode is electrically connected with the second MOS tube and used for controlling the on-off of the second MOS tube; the third triode is electrically connected with the second triode and used for controlling the on-off of the second triode; the first triode is also electrically connected to the main power supply module, the second triode is also electrically connected to the auxiliary power supply module, and the third triode is also electrically connected to the main power supply module and the auxiliary power supply module respectively. It is visible, the utility model provides a technical scheme adopts the active device as change over switch to reach the purpose of circuit break-make, and then accomplish the switching of main, secondary power supply. And active device compares with the relay, and switching speed is faster, operating frequency is higher, and contactless, can not produce electromagnetic interference for at the in-process that main, auxiliary power switched, the equipment of working is not switched by the power and is influenced, promptly, the utility model provides a technical scheme can realize the uninterrupted switching between main, auxiliary power, thereby guarantees the normal work of equipment.

The utility model discloses an on-off of triode control MOS pipe to reach the purpose of circuit break-make. The MOS tube is switched on for 6ns and switched off for 22ns, so that power switching can be completed quickly. And meanwhile, diodes are respectively added at the output ends of the main power supply circuit and the auxiliary power supply circuit to prevent the current from flowing backwards. In order to reduce the loss caused by the internal resistance of the MOS tubes, 4 MOS tubes are connected in parallel. The main power supply circuit and the auxiliary power supply circuit are controlled by 4 MOS tubes as switches through triodes. The triode is controlled by the main power supply module and/or the auxiliary power supply module.

The utility model relates to a main, vice automatic fast switch-over high accuracy power module scheme can realize switching in order to give the equipment power supply in the work, effectively lifting means's operating efficiency fast uninterruptedly between main, vice two kinds of power module. The scheme adopts the active device as a change-over switch, and compared with a relay, the switching speed is high, the working frequency is high, the loss to a power supply is less, a driving circuit is simple, no contact is made, and electromagnetic interference cannot be generated. Meanwhile, each device in the scheme has small volume and low cost, reduces the occupied space of the circuit board and is easy to realize.

Although the embodiments of the present invention have been disclosed, the above description is only for the convenience of understanding the present invention, and is not intended to limit the present invention. It will be apparent to persons skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. An automatic power switching circuit, comprising: the power supply comprises a main power supply module, an auxiliary power supply module, a first triode, a second triode, a third triode, a first MOS (metal oxide semiconductor) tube and a second MOS tube; the main power supply module is electrically connected to a load through the first MOS tube; the first triode is electrically connected with the first MOS tube and used for controlling the on-off of the first MOS tube; the auxiliary power supply module is electrically connected to a load through the second MOS tube; the second triode is electrically connected with the second MOS tube and used for controlling the on-off of the second MOS tube; the third triode is electrically connected with the second triode and used for controlling the on-off of the second triode; the first triode is also electrically connected to the main power supply module; the second triode is also electrically connected to the auxiliary power supply module; the third triode is also electrically connected to the main power supply module and the auxiliary power supply module respectively.

2. The automatic power switching circuit according to claim 1, wherein the first transistor, the second transistor, and the third transistor are NPN transistors; the first MOS tube and the second MOS tube are both PMOS tubes.

3. The automatic power switching circuit according to claim 2, wherein a source of the first MOS transistor is connected to the main power supply module, a drain of the first MOS transistor is connected to the load, and a gate of the first MOS transistor is connected to the main power supply module through a resistor R1; the collector electrode of the first triode is connected with the grid electrode of the first MOS tube through a resistor R2, the base electrode of the first triode is connected with the main power supply module through a resistor R3, and the emitting electrode of the first triode is grounded.

4. The automatic power switching circuit of claim 3, wherein at least one of the first MOS transistors is connected in parallel.

5. The automatic power switching circuit according to claim 2, wherein a source of the second MOS transistor is connected to the secondary power supply module, a drain of the second MOS transistor is connected to the load, and a gate of the second MOS transistor is connected to the secondary power supply module through a resistor R4; the collector electrode of the second triode is connected with the grid electrode of the second MOS tube through a resistor R5, the collector electrode of the second triode is also connected to the auxiliary power supply module through a resistor R6, the base electrode of the second triode is connected with the collector electrode of the third triode through a resistor R7, and the emitter electrode of the second triode is grounded; the collector of the third triode is also connected to the auxiliary power supply module through a resistor R8, and the emitter of the third triode is grounded; the base electrode of the third triode is connected with one end of a resistor R9, the other end of the resistor R9 is respectively connected with one end of a resistor R10 and one end of a resistor R11, the other end of the resistor R10 is connected to the main power supply module, and the other end of the resistor R11 is grounded.

6. The automatic power switching circuit of claim 5, further comprising: a bypass capacitor; one end of the bypass capacitor is connected with the base electrode of the second triode, and the other end of the bypass capacitor is grounded.

7. The automatic power switching circuit of claim 5, wherein at least one of the second MOS transistors is connected in parallel.

8. The automatic power switching circuit of claim 1, further comprising: a first diode and a second diode for preventing current from flowing backward; the first diode is arranged between the first MOS tube and the load; the second diode is arranged between the second MOS tube and the load.

9. The automatic power switching circuit of claim 8, wherein the first diode is at least one and the first diodes are connected in parallel; the second diode is at least one, and the second diodes are connected in parallel.

10. The automatic power switching circuit of claim 8, wherein a fuse is disposed between the first diode and the load and between the second diode and the load.

11. The automatic power switching circuit of claim 10, further comprising: at least one electrolytic capacitor connected in parallel with each other; the anode of the electrolytic capacitor is connected with the load, and the cathode of the electrolytic capacitor is grounded.