Main and standby power supply switching circuit for fire-fighting emergency power supply
By employing hardware interlocking of transistors, NMOS transistors, and capacitors, along with a parallel PMOS transistor structure in the fire emergency power switching circuit, the synchronization problem during the main and backup power switching process is solved, achieving stable power switching and simplified control logic, thereby improving the system's reliability and power supply continuity.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- QINGDAO DINGXIN COMM & FIRE FIGHTING SAFETY CO LTD
- Filing Date
- 2025-04-15
- Publication Date
- 2026-04-10
AI Technical Summary
The existing main and backup power switching circuits of fire emergency power supplies are prone to the risk of the main power supply and backup power supply being turned on simultaneously during the switching process, which can lead to instantaneous high current or logic failure. In addition, the control signal synchronization requirements are high, which increases the system complexity and failure risk.
The system employs a combination of transistors, NMOS transistors, and capacitors, utilizing complementary signals from ports IO1 and IO2 to achieve hardware interlocking for main/standby power switching. A parallel PMOS transistor structure maintains power supply to the output circuit during switching, while resistors and electrolytic capacitors suppress voltage fluctuations, simplifying the control logic.
It achieves safety and stability in the switching between primary and backup power supplies, avoids the risk of the primary and backup power supplies being turned on simultaneously, improves power supply continuity and system reliability, and reduces circuit complexity and failure risk.
Smart Images
Figure CN224110941U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to the technical field of fire emergency power supply switching, and particularly relates to a main and standby power supply switching circuit for a fire emergency power supply. BACKGROUND
[0002] The main and standby power supply switching circuit of the fire emergency power supply is an important technology for ensuring continuous power supply of fire equipment, and the main and standby power supply switching usually adopts a combination of a relay and a MOS tube to avoid power supply interruption in the switching moment. However, in the switching process, there is a hidden danger that the main power supply and the standby power supply are turned on at the same time, and the voltage difference between the two can cause instantaneous large current or logic failure, resulting in reduced power supply reliability, and the switching is realized by time sequence control, which requires high synchronization of the control signal and increases the system complexity and risk of failure.
[0003] The main and standby power supply switching circuit for fire emergency host power supply disclosed in the prior art with the publication number CN212114884U includes a relay module, a main voltage acquisition module, a voltage reference source and a switching module. The main voltage acquisition module detects the main power output voltage in real time. When the main voltage is lower than the set value, the voltage reference source triggers the MOS tube in the switching module to be turned on, so that the standby power supply provides short-time power supply to the subsequent circuit, and at the same time, the relay module completes the main and standby power supply switching to avoid power-off restart. However, in the relay switching process, there is a time difference between the MOS tube conduction and the relay contact switching in the circuit, which causes the main power supply and the standby power supply to be short-circuited in parallel for a short time. If the voltages of the two are not matched, instantaneous large current or logic failure may occur, which reduces the system reliability, and the switching process requires precise time sequence cooperation, which requires high synchronization of the control signal, increases the complexity of the circuit and the risk of failure. UTILITY MODEL CONTENTS
[0004] The utility model solves the technical problem of overcoming the defects in the prior art and providing a main and standby power supply switching circuit for a fire emergency power supply.
[0005] The technical scheme adopted by the utility model is as follows:
[0006] The main and standby power supply switching circuit for a fire emergency power supply, comprising a main power supply VCC main , a standby power supply VCC bat and an output loop VCC out , further comprising a main power supply control module, a main power supply switch, a standby power supply control module, a standby power supply switch and a microcontroller MCU, the microcontroller MCU includes a port IO1 and a port IO2, the port IO1 is connected to the main power supply control module, the main power supply control module is connected to the main power supply switch, and the main power supply switch is connected to the main power supply VCC main and the output loop VCC out, the port IO2 is connected with the standby power control module, the standby power control module is connected with the standby power switch, and the standby power switch is connected with the standby power VCC bat and the output loop VCC out .
[0007] The main power control module comprises a capacitor C1, a resistor R1, a resistor R2, a triode VT1 and an NMOS tube VM3, one end of the capacitor C1 and one end of the resistor R1 are connected with the port IO1, the other end of the capacitor C1 is grounded, the other end of the resistor R1 is connected with the base of the triode VT1, the collector of the triode VT1 is connected with the main power switch, the emitter of the triode VT1 is connected with one end of the resistor R2, the other end of the resistor R2 is connected with the source of the NMOS tube VM3, the drain of the NMOS tube VM3 is connected with the base of the triode VT1, the source of the NMOS tube VM3 is grounded, and the gate of the NMOS tube VM3 is connected with the port IO2.
[0008] The main power switch comprises a PMOS tube VM1, a PMOS tube VM2 and a resistor R3, the drain of the PMOS tube VM1 is connected with the main power VCC main , the source of the PMOS tube VM1 is connected with the output loop VCC out , the gate of the PMOS tube VM1 is connected with the collector of the triode VT1, the drain of the PMOS tube VM2 is connected with the drain of the PMOS tube VM1, the source of the PMOS tube VM2 is connected with the output loop VCC out , the gate of the PMOS tube VM2 is connected with the collector of the triode VT1, one end of the resistor R3 is connected with the collector of the triode VT1, and the other end of the resistor R3 is connected with the output loop VCC out .
[0009] The standby power control module comprises a capacitor C2, a resistor R4, a resistor R5, a triode VT2 and an NMOS tube VM5, one end of the capacitor C2 and one end of the resistor R4 are connected with the port IO2, one end of the capacitor C2 is grounded, the other end of the resistor R4 is connected with the base of the triode VT2, the collector of the triode VT2 is connected with the standby power switch, the emitter of the triode VT2 is connected with one end of the resistor R5, the other end of the resistor R5 is connected with the source of the NMOS tube VM5, the drain of the NMOS tube VM5 is connected with the base of the triode VT2, the source of the NMOS tube VM5 is grounded, and the gate of the NMOS tube VM5 is connected with the port IO1.
[0010] The standby power switch comprises a PMOS tube VM4, a PMOS tube VM6 and a resistor R6, the drain of the PMOS tube VM4 is connected with the standby power VCC bat , the source of the PMOS tube VM4 is connected with the output loop VCC outThe gate of the PMOS tube VM4 is connected with the collector of the triode VT2, the drain of the PMOS tube VM6 is connected with the drain of the PMOS tube VM4, and the source of the PMOS tube VM6 is connected with the output loop VCC out The gate of the PMOS tube VM6 is connected with the collector of the triode VT2, one end of the resistor R6 is connected with the collector of the triode VT2, and the other end is connected with the output loop VCC out .
[0011] The resistor R6 is connected with the output loop VCC out , and the other end of the electrolytic capacitor E1 is grounded.
[0012] The utility model has the following beneficial effects:
[0013] 1. Through the cooperation of the triode, the NMOS tube and the capacitor, the complementary signal control of the ports IO1 and IO2 is utilized to realize the hardware interlocking of the main and standby power switching, and the risk of the main power supply and the standby power supply being turned on at the same time is avoided.
[0014] 2. Through the parallel structure of the PMOS tubes VM1 and VM2 and the parallel structure of the PMOS tubes VM4 and VM6, the body diode characteristics are utilized to maintain the output loop power supply at the switching moment, eliminate the short-time interruption problem and improve the power supply continuity.
[0015] 3. The resistor R3, the resistor R6 and the electrolytic capacitor E1 can effectively inhibit the voltage fluctuation when the switch is operated, ensure the stability of the output loop voltage and reduce the impact of the instantaneous current on the circuit.
[0016] 4. The IO1 and IO2 output high and low level complementary signals, simplify the control logic, reduce the software intervention, improve the system response speed and reliability. BRIEF DESCRIPTION OF DRAWINGS
[0017] Figure 1 It is the circuit principle drawing of the utility model. CONCRETE IMPLEMENTATION
[0018] As Figure 1 shown, the main and standby power switching circuit for the fire emergency power supply provided by the utility model, including main power supply VCC main , standby power supply VCC bat and output loop VCC out , also includes main power supply control module, main power supply switch, standby power supply control module, standby power supply switch and microcontroller MCU, microcontroller MCU includes port IO1 and port IO2, port IO1 connects main power supply control module, main power supply control module connects main power supply switch, main power supply switch connects main power supply VCC main and output loop VCC out, the port IO2 is connected with the standby power control module, the standby power control module is connected with the standby power switch, and the standby power switch is connected with the standby power VCC bat and the output loop VCC out .
[0019] The main power control module comprises a capacitor C1, a resistor R1, a resistor R2, a triode VT1 and an NMOS tube VM3, one end of the capacitor C1 and one end of the resistor R1 are connected with the port IO1, the other end of the capacitor C1 is grounded, the other end of the resistor R1 is connected with the base of the triode VT1, the collector of the triode VT1 is connected with the main power switch, the emitter of the triode VT1 is connected with one end of the resistor R2, the other end of the resistor R2 is connected with the source of the NMOS tube VM3, the drain of the NMOS tube VM3 is connected with the base of the triode VT1, the source of the NMOS tube VM3 is grounded, and the gate of the NMOS tube VM3 is connected with the port IO2.
[0020] The main power switch comprises a PMOS tube VM1, a PMOS tube VM2 and a resistor R3, the drain of the PMOS tube VM1 is connected with the main power VCC main , the source of the PMOS tube VM1 is connected with the output loop VCC out , the gate of the PMOS tube VM1 is connected with the collector of the triode VT1, the drain of the PMOS tube VM2 is connected with the drain of the PMOS tube VM1, the source of the PMOS tube VM2 is connected with the output loop VCC out , the gate of the PMOS tube VM2 is connected with the collector of the triode VT1, one end of the resistor R3 is connected with the collector of the triode VT1, and the other end of the resistor R3 is connected with the output loop VCC out .
[0021] The standby power control module comprises a capacitor C2, a resistor R4, a resistor R5, a triode VT2 and an NMOS tube VM5, one end of the capacitor C2 and one end of the resistor R4 are connected with the port IO2, one end of the capacitor C2 is grounded, the other end of the resistor R4 is connected with the base of the triode VT2, the collector of the triode VT2 is connected with the standby power switch, the emitter of the triode VT2 is connected with one end of the resistor R5, the other end of the resistor R5 is connected with the source of the NMOS tube VM5, the drain of the NMOS tube VM5 is connected with the base of the triode VT2, the source of the NMOS tube VM5 is grounded, and the gate of the NMOS tube VM5 is connected with the port IO1.
[0022] The standby power switch comprises a PMOS tube VM4, a PMOS tube VM6 and a resistor R6, the drain of the PMOS tube VM4 is connected with the standby power VCC bat , the source of the PMOS tube VM4 is connected with the output loop VCC outThe gate of the PMOS tube VM4 is connected with the collector of the triode VT2, the drain of the PMOS tube VM6 is connected with the drain of the PMOS tube VM4, and the source of the PMOS tube VM6 is connected with the output loop VCC out The gate of the PMOS tube VM6 is connected with the collector of the triode VT2, one end of the resistor R6 is connected with the collector of the triode VT2, and the other end is connected with the output loop VCC out .
[0023] The resistor R6 is connected with the output loop VCC out , and the other end is grounded.
[0024] Specifically, when the main power supply VCC main is normally supplied, the microcontroller MCU outputs high level through the port IO1, and the port IO2 outputs low level at the same time; the high level of IO1 drives the triode VT1 to be turned on through the resistor R1, the voltage of the collector of VT1 is pulled down, and then the gate voltage of the PMOS tubes VM1 and VM2 in the main power supply switch is lowered; since the PMOS tube has the characteristic of being turned on at low level, the main power supply VCC main is supplied to the output loop VCC out through the source of the PMOS tube VM1 and the source of the PMOS tube VM2. The low level of the port IO2 makes the triode VT2 in the standby power supply control module be turned off, the gate of the PMOS tube VM4 and the gate of the PMOS tube VM6 in the standby power supply switch remain high level, and the standby power supply VCC bat is isolated from the output loop VCC out . The low level of the port IO2 also acts on the NMOS tube VM3 in the main power supply control module, so that the NMOS tube VM3 is turned off, avoiding interference to the main power supply control module; at the same time, the high level of the port IO1 is conducted through the NMOS tube VM5 in the standby power supply control module, so that the base potential of the triode VT2 is pulled down, further ensuring that the standby power supply control module is completely closed.
[0025] Specifically, when the main power supply VCC main abnormally drops, the microcontroller MCU detects that the main power supply VCC main fails, immediately sets the port IO1 to low level and the port IO2 to high level, at this time, the main power supply control module is closed and the standby power supply control module is activated, realizing standby power supply.
[0026] Specifically, when the main power supply VCC main recovers, the microcontroller MCU re-detects the main power supply VCC mainNormally, the port IO1 is set to high level, the port IO2 is set to low level, the resistors R3 and R6 are connected in parallel between the gate-source of the PMOS tube VM1, the PMOS tube VM2 and the PMOS tube VM4, the PMOS tube VM6, to provide a discharge circuit, to accelerate the switch-off, the electrolytic capacitor E1 is connected to the output circuit VCC out Parallel connection, absorbing voltage fluctuation in switching moment, ensuring stable output voltage.
Claims
1. A main and standby power switching circuit for a fire emergency power supply, comprising a main power supply VCC main , a standby power supply VCC bat and an output circuit VCC out , characterized in that, Also include main power control module, main power switch, standby power control module, standby power switch and microcontroller MCU, the microcontroller MCU includes port IO1 and port IO2, the port IO1 is connected main power control module, the main power control module is connected main power switch, the main power switch is connected main power VCC main And output loop VCC out , the port IO2 is connected standby power control module, the standby power control module is connected standby power switch, the standby power switch is connected standby power VCC bat And output loop VCC out .
2. The master and standby power switching circuit for fire emergency power supply according to claim 1, characterized in that, The main power supply control module includes a capacitor C1, a resistor R1, a resistor R2, a triode VT1 and an NMOS tube VM3, one end of the capacitor C1 and one end of the resistor R1 are connected to the port IO1, the other end of the capacitor C1 is grounded, the other end of the resistor R1 is connected to the base of the triode VT1, the collector of the triode VT1 is connected to the main power supply switch, the emitter of the triode VT1 is connected to one end of the resistor R2, the other end of the resistor R2 is connected to the source of the NMOS tube VM3, the drain of the NMOS tube VM3 is connected to the base of the triode VT1, the source of the NMOS tube VM3 is grounded, and the gate of the NMOS tube VM3 is connected to the port IO2.
3. The master-slave power switching circuit for fire emergency power supply according to claim 2, wherein, The main power switch comprises a PMOS tube VM1, a PMOS tube VM2 and a resistor R3, the drain of the PMOS tube VM1 is connected with a main power supply VCC main , the source of the PMOS tube VM1 is connected with an output loop VCC out , the gate of the PMOS tube VM1 is connected with the collector of a triode VT1, the drain of the PMOS tube VM2 is connected with the drain of the PMOS tube VM1, the source of the PMOS tube VM2 is connected with the output loop VCC out , the gate of the PMOS tube VM2 is connected with the collector of the triode VT1, one end of the resistor R3 is connected with the collector of the triode VT1, and the other end is connected with the output loop VCC out .
4. The master-slave power switching circuit for fire emergency power supply according to claim 1, wherein The standby power supply control module includes a capacitor C2, a resistor R4, a resistor R5, a triode VT2 and an NMOS tube VM5, one end of the capacitor C2 and one end of the resistor R4 are connected to the port IO2, one end of the capacitor C2 is grounded, the other end of the resistor R4 is connected to the base of the triode VT2, the collector of the triode VT2 is connected to the standby power supply switch, the emitter of the triode VT2 is connected to one end of the resistor R5, the other end of the resistor R5 is connected to the source of the NMOS tube VM5, the drain of the NMOS tube VM5 is connected to the base of the triode VT2, the source of the NMOS tube VM5 is grounded, and the gate of the NMOS tube VM5 is connected to the port IO1.
5. The master-slave power switching circuit for fire emergency power supply according to claim 4, wherein, The standby power supply switch comprises a PMOS tube VM4, a PMOS tube VM6 and a resistor R6, the drain of the PMOS tube VM4 is connected with a standby power supply VCC bat , the source of the PMOS tube VM4 is connected with an output loop VCC out , the gate of the PMOS tube VM4 is connected with the collector of a triode VT2, the drain of the PMOS tube VM6 is connected with the drain of the PMOS tube VM4, the source of the PMOS tube VM6 is connected with the output loop VCC out , the gate of the PMOS tube VM6 is connected with the collector of the triode VT2, one end of the resistor R6 is connected with the collector of the triode VT2, and the other end is connected with the output loop VCC out .
6. The master-slave power switching circuit for fire emergency power supply according to claim 5, wherein, The resistance R6 connects one end of the output loop VCC out The other end of the electrolytic capacitor E1 is grounded.
Citation Information
Patent Citations
Main-standby power switching circuit for fire emergency host power supply
CN212114884U