Direct-current emergency lighting power supply circuit

Abstract

The invention discloses a direct-current emergency lighting power supply circuit, which comprises a dual-power-supply change-over switch, a rectifier, a storage battery pack, a charger, a chopper, an output loop, a local control system and a remote control center, and is characterized in that the dual-power-supply change-over switch is connected with the storage battery pack through the charger; the dual-power change-over switch is connected with the output loop through the rectifier to supply power to the load to form a constant power supply loop, the storage battery pack is connected with the output loop through the chopper to supply power to the load to form an emergency power supply loop, and the storage battery pack is directly connected with the output loop to supply power to the load to form a battery direct supply loop. Direct current provided by the constant power supply loop, the emergency power supply loop and the battery direct supply loop is output by a main output switch of the output loop, and the output loop is provided with a bypass output switch. According to the invention, the diversified and high-standard requirements of users can be met, the rectifier, the charger and the chopper have redundant design and high reliability, and the output voltage can be adjusted through a local control system and remotely controlled through an upper computer.

Description

Technical Field

[0001] The invention belongs to the technology of fire emergency lighting power supply, and in particular relates to a direct current emergency lighting power supply circuit. Background Art

[0002] Fire emergency lighting power supply is a fire emergency power supply. When the mains fails or is abnormal, it can continue to supply power to the load to meet the requirements of fire emergency, evacuation lighting, and indication, and provide guarantee for safe emergency power supply after power outage. The output of the existing fire emergency lighting power supply is AC power. Now the AC emergency lighting power supply is directly powered by the mains under normal power supply. When the mains fails, the inverter converts the DC power stored in the battery into AC power. Due to the high cost, the inverter generally does not have a redundant design. Therefore, in the emergency power supply mode, the reliability is relatively low.

[0003] Since DC power has the advantages of strong stability, easy control, low interference, and more load-friendly, it is expected to become an emergency power supply method in the future. However, there are currently no DC emergency lighting power supply products on the market. Summary of the invention

[0004] The object of the present invention is to provide a DC emergency lighting power supply circuit which has low cost, high reliability and can meet various application requirements.

[0005] The object of the present invention is achieved by the following technical solution: A DC emergency lighting power supply circuit, characterized in that it includes:

[0006] The dual power switch is used to automatically switch between the two AC power supplies provided by the mains according to the set working mode;

[0007] A rectifier is used to rectify the AC power output by the dual power supply switch into DC power and provide it to the output circuit to power the load;

[0008] The battery pack is used to store electrical energy and is responsible for supplying power to the output circuit to provide emergency power for the load when the mains fails;

[0009] A charger, used to rectify the AC power output by the dual power supply switch into DC power to charge the battery pack;

[0010] Chopper, used to convert the power of the battery pack into stable output DC power when the mains fails;

[0011] Output circuit, used to switch the working mode so that the load can obtain electric energy in both normal power supply and emergency power supply state;

[0012] A local control system is used to locally monitor the operating status of each component;

[0013] Remote control center, used to remotely control the operation of each component;

[0014] The rectifier, charger and chopper all have redundant designs. The dual power supply switching switch is connected to the battery pack through the charger to charge the battery pack. The dual power supply switching switch is connected to the output circuit through the rectifier to supply power to the load to form a normal power supply circuit. The battery pack is connected to the output circuit through the chopper to supply power to the load to form an emergency power supply circuit. The battery pack is directly connected to the output circuit to supply power to the load to form a battery direct supply circuit. The DC power provided by the normal power supply circuit, the emergency power supply circuit and the battery direct supply circuit are all output by the total output switch of the output circuit, and the output circuit has a bypass output switch.

[0015] The present invention fills the blank problem of the lack of DC emergency lighting power supply products on the market, and can meet the diverse and high-standard requirements of users. The rectifier, charger and chopper of the present invention all have redundant design and high reliability. The output voltage can be adjusted through the local control system (monitor and main control unit) and can be remotely controlled by the host computer.

[0016] The rectifier of the present invention adopts a high-frequency switching power supply rectifier circuit and is controlled by a local control system.

[0017] The charger of the present invention adopts a high-frequency switching power supply rectification circuit and is controlled by a local control system.

[0018] The chopper of the present invention adopts a high-frequency switching chopper circuit and is controlled by a local control system.

[0019] The output circuit of the present invention is composed of a rectifier output circuit contactor connected to a rectifier, a chopper circuit contactor connected to a chopper, a battery direct supply circuit contactor connected to a battery pack, a total output switch, a bypass output switch and a contactor control circuit.

[0020] The local control system of the present invention performs a power-on self-check function when the system is powered on to detect whether each component has a fault. If there is no serious fault or the number of faults does not exceed the set range, it can operate normally, otherwise it outputs an alarm prompt.

[0021] When the mains power is cut off, the rectifier and the charger are shut down, the chopper circuit contactor KM2 is closed, and the rectifier output circuit contactor KM1 is opened to maintain emergency output and report related faults such as serious faults; when the mains power is restored, it automatically returns to the main power supply state.

[0022] When the output is short-circuited, the present invention closes the chopping circuit contactor KM2 and opens the rectifier output circuit contactor KM1, uses the emergency power supply mode to support the short-circuit current, and after eliminating the short-circuit fault current, closes the rectifier output circuit contactor KM1 again and opens the chopping circuit contactor KM2 to restore the normal power supply mode;

[0023] When the short-circuit output occurs, the normal power supply mode and the emergency power supply mode cannot support the elimination of the short-circuit current. Keep the chopper circuit contactor KM2 and the battery direct supply circuit contactor KM3 closed, and at the same time, open the rectifier output circuit contactor KM1, and use the battery direct supply mode; when the battery supports the elimination of the short-circuit current, open the battery direct supply circuit contactor KM3, close the rectifier output circuit contactor KM1, and then open the chopper circuit contactor KM2 to restore the normal power supply state;

[0024] When the output is short-circuited, the battery direct supply mode cannot support the elimination of the short-circuit current, and the chopper circuit contactor KM2 / battery direct supply circuit contactor KM3 are disconnected, and the fault stops in a steady state.

[0025] When the battery pack voltage drops to the termination voltage, the present invention alarms that the battery pack voltage is low to the termination voltage fault, and the battery pack is shut down for low voltage protection. In an emergency, the battery pack can be manually operated to the battery direct supply mode.

[0026] Compared with the prior art, the present invention has the following significant effects:

[0027] (1) The present invention fills the gap of no DC emergency lighting power supply products on the market and can meet the diverse and high-standard requirements of users.

[0028] (2) The present invention can provide a stable and controllable DC power supply: the rectifier, charger and chopper all have a redundant design and high reliability. The output voltage can be adjusted by a local control system and can be remotely controlled by a host computer.

[0029] ⑶ Traditionally, the lamp load using AC power needs to be configured with a rectifier AC / DC part + DC / DC part, and the adapter efficiency is low. The lamp load using the DC power supply of the present invention only needs to be configured with a DC / DC part, and the adapter efficiency is high, which is load-friendly and helps to extend the load life. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0031] Figure 1 is a circuit diagram of the present invention;

[0032] Figure 2 It is a schematic diagram of the connection between the local control system and various components of the present invention. DETAILED DESCRIPTION

[0033] like Figure 1 and Figure 2 As shown, the present invention provides a DC emergency lighting power supply circuit, comprising:

[0034] The dual power switch is used to automatically switch between the two AC power supplies provided by the mains according to the set working mode;

[0035] The rectifier is used to rectify the AC power output by the dual power supply switching switch into DC power and provide it to the output circuit to power the load; the rectifier adopts a high-frequency switching power supply rectifier circuit, and the output voltage of the rectifier is set by the local control system (monitor and main control unit); the local control system establishes physical communication with the rectifier S485 serial communication port through the RS485 serial communication port, and the protocol is the Modbus-RTU protocol; the PLC sends instructions to each rectifier with a fixed address through a message, and the rectifier executes the command to run.

[0036] The battery pack is used to store electrical energy and is responsible for supplying power to the output circuit to provide emergency power for the load when the mains fails;

[0037] The charger is used to rectify the AC power output by the dual power supply switch into high-quality DC power to charge the battery pack. The charger adopts a high-frequency switching power supply rectification circuit. The charging mode, charging voltage and current of the charger are automatically set by the local control system according to the program; the local control system establishes physical communication with the charger S485 serial communication port through the RS485 serial communication port, and the protocol is the Modbus-RTU protocol; the PLC sends instructions to each charger with a fixed address through a message, and the charger executes the command to run.

[0038] The chopper is used to convert the battery power into stable high-quality DC power when the mains fails. The output voltage of the chopper can be set through the local control system. The chopper uses a high-frequency switch chopper circuit. The local control system establishes physical communication with the chopper S485 serial communication port through the RS485 serial communication port. The protocol is Modbus-RTU protocol. The PLC sends instructions to each chopper with a fixed address through a message, and the chopper executes the command to run.

[0039] The output circuit is used to switch the working mode so that the load can obtain power in both normal power supply and emergency power supply state; that is, it is responsible for switching the normal power supply circuit, emergency circuit, and battery direct supply circuit to ensure that the load can obtain power in both normal power supply and emergency power supply state. The output circuit consists of a rectifier output circuit contactor connected to the rectifier, a chopper circuit contactor connected to the chopper, a battery direct supply circuit contactor connected to the battery pack, a total output switch, a bypass output switch, and a contactor control circuit.

[0040] The local control system is used to monitor the operating status of each component locally and control its effective operation. The local control system is usually located near the monitored circuit and has a relatively direct connection with the circuit. It generally collects various parameters of the circuit in real time through sensors and other devices, such as voltage, current, temperature, etc., and performs local control according to the preset logic. For example, when it is detected that the circuit temperature is too high, the local control system can directly start the cooling device or adjust the working status of the circuit.

[0041] The remote control center is used to remotely control the operation of each component; the remote control center is generally located in the remote control center and connected to the circuit or local control system through a communication network. The host computer is mainly presented in the form of a software interface, and the operator can operate remotely through input devices such as a mouse and keyboard to send control instructions to the circuit.

[0042] The dual power supply switch is connected to the battery pack through a charger to charge the battery, the dual power supply switch is connected to the output circuit through a rectifier to supply power to the load to form a normal power supply circuit, the battery pack is connected to the output circuit through a chopper to supply power to the load to form an emergency power supply circuit, and the battery pack is directly connected to the output circuit to supply power to the load to form a battery direct supply circuit (in an emergency state, when the chopper fails, the battery direct supply circuit supplies power to the load; when a short circuit occurs in the load circuit, the battery direct supply circuit provides a short-circuit current that can trip the circuit breaker, thereby quickly removing the short circuit fault), and the DC power provided by the normal power supply circuit, the emergency power supply circuit and the battery direct supply circuit are all output by the total output switch QF4 of the output circuit.

[0043] Rectifiers, chargers and choppers all have redundant designs, which is a design method used to improve system reliability and stability. Specifically, it is to add some additional resources or functional modules to the system. These redundant parts may be idle under normal circumstances, but when some key parts of the system fail, they can replace the failed parts in time to ensure that the system can continue to operate normally. For example, when the combined power supply of 4 rectifiers can normally meet the load demand, the design will also add a set of rectifiers in hot standby state at the same time. When any one device fails, the standby rectifier can be immediately switched to work.

[0044] The present invention has the following four working modes:

[0045] 1. Normal power supply mode: including monitor & main control unit, dual power switch, rectifier, charger and output circuit (including DC contactor KM1 and main output switch QF4);

[0046] 2. Emergency power supply mode: including local control system, battery pack, chopper and output circuit (including DC contactor KM2 and main output switch QF4);

[0047] 3. Battery direct supply mode: including local control system, battery pack and output circuit (including DC contactor KM3 and main output switch QF4);

[0048] 4. Bypass mode: bypass output switch QF5.

[0049] The local control system of the present invention performs a power-on self-check function when the system is powered on to detect that the rectifier, chopper, charger and other components have no serious faults or the number of faults does not exceed the set range before normal operation; if there is a serious fault, an alarm prompt is output.

[0050] When the dual power switch of the present invention is abnormal (mains power outage), after the mains power outage, the rectifier and charger are shut down, the chopper circuit contactor KM2 is closed, and the rectifier output circuit contactor KM1 is opened to maintain emergency output. The event reports a serious fault and other related faults. When the mains power is restored, it automatically returns to the main power supply state, and the switching process takes about 100ms.

[0051] The present invention has perfect output circuit short-circuit protection control:

[0052] 1. When the output is short-circuited, the rectifier cannot support the short-circuit current in the normal power supply mode. Close KM2 and open KM1. Use the emergency power supply mode to support the short-circuit current. After eliminating the short-circuit fault current, close KM1 again, open KM2, and restore the normal power supply mode.

[0053] 2. When the output is short-circuited, the normal power supply mode + emergency power supply mode cannot support the elimination of the short-circuit current. The battery direct supply mode is adopted to keep KM2+KM3 closed and disconnect KM1 at the same time; when the battery supports the elimination of the short-circuit current for about 2 seconds, disconnect KM3, close KM1, and then disconnect KM2 to restore the normal power supply state.

[0054] 3. When the output is short-circuited, the battery direct supply mode cannot support the elimination of the short-circuit current, and the KM2 / KM3 is disconnected (alarm and fault report: prompt "The output short circuit cannot be cleared, be sure to thoroughly check and clear the short-circuit point before putting the equipment into use!"), and then the fault stops in steady state E4.

[0055] The emergency power supply mode of the present invention: when the battery pack voltage is lower than the termination voltage, an alarm is issued for the battery pack voltage being lower than the termination voltage fault, prompting the battery pack to shut down for low voltage protection. In an emergency, S8 can be manually switched to the battery direct supply mode, but the battery pack may be discharged and damaged.

[0056] The embodiments of the present invention are not limited to this. According to the above contents of the present invention, in accordance with common technical knowledge and customary means in the art, without departing from the above basic technical ideas of the present invention, the heat dissipation structure of the present invention also has other embodiments. Therefore, the present invention can also make other various forms of modification, replacement or change, all of which fall within the scope of protection of the present invention.

Claims

1. A DC emergency lighting power supply circuit, characterized in that include: The dual power switch is used to automatically switch between the two AC power supplies provided by the mains according to the set working mode; A rectifier is used to rectify the AC power output by the dual power supply switch into DC power and provide it to the output circuit to power the load; The battery pack is used to store electrical energy and is responsible for supplying power to the output circuit to provide emergency power for the load when the mains fails; A charger, used to rectify the AC power output by the dual power supply switch into DC power to charge the battery pack; Chopper, used to convert the power of the battery pack into stable output DC power when the mains fails; Output circuit, used to switch the working mode so that the load can obtain electric energy in both normal power supply and emergency power supply state; A local control system is used to locally monitor the operating status of each component; Remote control center, used to remotely control the operation of each component; The rectifier, charger and chopper all have redundant designs. The dual power supply switching switch is connected to the battery pack through the charger to charge the battery assembly. The dual power supply switching switch is connected to the output circuit through the rectifier to supply power to the load to form a normal power supply circuit. The battery pack is connected to the output circuit through the chopper to supply power to the load to form an emergency power supply circuit. The battery pack is directly connected to the output circuit to supply power to the load to form a battery direct supply circuit. The DC power provided by the normal power supply circuit, the emergency power supply circuit and the battery direct supply circuit are all output by the total output switch of the output circuit, and the output circuit has a bypass output switch.

2. The DC emergency lighting power supply circuit according to claim 1, characterized in that: The rectifier adopts a high-frequency switching power supply rectifier circuit and is controlled by a local control system.

3. The DC emergency lighting power supply circuit according to claim 2 is characterized in that: The charger adopts a high-frequency switching power supply rectification circuit and is controlled by a local control system.

4. The DC emergency lighting power supply circuit according to claim 3 is characterized in that: The chopper adopts a high-frequency switching chopper circuit and is controlled by a local control system.

5. The DC emergency lighting power supply circuit according to claim 4, characterized in that: The output circuit is composed of a rectifier output circuit contactor connected to the rectifier, a chopper circuit contactor connected to the chopper, a battery direct supply circuit contactor connected to the battery pack, a total output switch, a bypass output switch and a contactor control circuit.

6. The DC emergency lighting power supply circuit according to claim 5, characterized in that: The local control system performs a power-on self-check function when the system is powered on to detect whether each component has a fault. If there is no serious fault or the number of faults does not exceed the set range, it can operate normally, otherwise it outputs an alarm prompt.

7. The DC emergency lighting power supply circuit according to claim 6, characterized in that: When the city power is cut off, the rectifier and charger are shut down, the chopper circuit contactor KM2 is closed, and the rectifier output circuit contactor KM1 is opened to maintain the emergency output, and the event reports serious faults and other related faults; when the city power is restored, it automatically returns to the main power supply state.

8. The DC emergency lighting power supply circuit according to claim 7, characterized in that: When the output is short-circuited, close the chopper circuit contactor KM2 and open the rectifier output circuit contactor KM1, use the emergency power supply mode to support the short-circuit current, and after eliminating the short-circuit fault current, reclose the rectifier output circuit contactor KM1 and open the chopper circuit contactor KM2 to restore the normal power supply mode; When the short-circuit output occurs, the normal power supply mode and the emergency power supply mode cannot support the elimination of the short-circuit current. Keep the chopper circuit contactor KM2 and the battery direct supply circuit contactor KM3 closed, and at the same time, open the rectifier output circuit contactor KM1, and use the battery direct supply mode; when the battery supports the elimination of the short-circuit current, open the battery direct supply circuit contactor KM3, close the rectifier output circuit contactor KM1, and then open the chopper circuit contactor KM2 to restore the normal power supply state; When the output is short-circuited, the battery direct supply mode cannot support the elimination of the short-circuit current, and the chopper circuit contactor KM2 / battery direct supply circuit contactor KM3 are disconnected, and the fault stops in a steady state.

9. The DC emergency lighting power supply circuit according to claim 8, characterized in that: When the battery pack voltage is lower than the termination voltage, an alarm will be issued for the battery pack voltage being lower than the termination voltage fault, and the battery pack will shut down for low voltage protection. In an emergency, the system can be manually operated to the battery direct supply mode.

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