Highly sensitive power failure detection method for LED emergency lighting devices

Abstract

The present application relates to the technical field of power failure detection for emergency lighting, and specifically to a high-sensitivity power failure detection method for LED emergency lighting devices, the method comprising: setting a master control emergency device before installing the emergency circuit; adopting a master-slave communication control mode for several emergency devices connected in parallel; when the emergency device has a mixed parallel connection state of the live input L phase and the neutral input N phase, the switch is operated "on-off-on-off", and the DPL and DPN of the master control emergency device output complementary square wave signals, and the ACL and ACN inside the "master-slave" emergency device learn square wave pulse width signals, adjust the high and low level output phases of ACL and ACN; and detect the level through the internal emergency detection circuit. The present application aims to detect the pulse width of the synchronization signal by adopting the master control communication control mode, realize the emergency detection logic recognition, and improve the sensitivity of the power failure detection of the emergency device.

Description

Technical Field

[0001] The present application relates to the technical field of emergency lighting power failure detection, and in particular to a high-sensitivity power failure detection method for LED emergency lighting devices. Background Art

[0002] When power is interrupted, LED emergency lighting devices need to be activated immediately to provide necessary lighting and ensure the safe evacuation of personnel. Especially in emergency situations, highly sensitive power failure detection methods ensure that the device can quickly detect power outages or voltage drops, avoiding false alarms or missed alarms and improving system reliability.

[0003] Most of the existing power-off detection methods adopt a parallel mixed zero-live wire identification control scheme. Its working principle is that when multiple lighting devices are used in parallel, the input zero-live wire phase is collected to adjust the AC check pin level phase to achieve a parallel mixed synchronization function, thereby further realizing the controllable wall switch in an emergency state.

[0004] However, when there is residual voltage on the grid bus or the grid voltage wave is disturbed or the sine wave is distorted, the above scheme will fail to detect the zero-live phase, resulting in errors in the recognition of the zero-live phase detection and loss of control of the emergency wall switch, affecting the sensitivity of the emergency power off detection. Summary of the invention

[0005] In order to solve the above technical problems, the present application provides a high-sensitivity power failure detection method for an LED emergency lighting device to solve the existing problems.

[0006] The high-sensitivity power failure detection method for LED emergency lighting devices of the present application adopts the following technical solutions:

[0007] One embodiment of the present application provides a high-sensitivity power failure detection method for an LED emergency lighting device, the method comprising:

[0008] Before installing the emergency circuit, set up a master control emergency device; for several emergency devices connected in parallel, use a master-slave communication control mode, set one of the emergency devices as the master control emergency device, and the others as slave control emergency devices;

[0009] When the emergency device has a mixed connection state of live input L phase and neutral input N phase in parallel, operate the switch "on-off-on-off", the L phase detection signal output DPL and N phase detection signal output DPN of the master emergency device output complementary square wave signals, and the AC live circuit output ACL and AC neutral circuit output ACN inside the "master-slave" emergency device learn square wave pulse width signals, and adjust the high and low level output phases of ACL and ACN;

[0010] The level is detected by the internal emergency detection circuit.

[0011] Preferably, the setting method of the master control emergency device is: "short-circuit-disconnect" the L and N phases of the emergency device input 6 times within 6 seconds.

[0012] Preferably, DPL outputs a high level for all emergency devices in the learning process, and DPN outputs a high level for the emergency device verification process.

[0013] Preferably, the signal learning process specifically includes: presetting the square wave pulse duration of DPL and DPN of the master emergency device, and determining whether ACL and ACN are master synchronization signals by determining the square wave pulse duration in the loop during the learning process.

[0014] Preferably, in addition to alternating current, the current type in the power failure detection process also includes direct current.

[0015] Preferably, the internal emergency detection circuit adopts a Schmitt trigger, and the pull-up resistor RH and the pull-down resistor RL provide an emergency detection reference through battery power supply voltage division.

[0016] Preferably, the emergency detection reference is 0.51 times the battery voltage.

[0017] Preferably, the phase adjustment process is performed in a state where there is no AC input and the switch is disconnected.

[0018] Preferably, after the level is detected by the internal emergency detection circuit, it is further determined whether to perform emergency lighting.

[0019] Preferably, the method for judging the emergency lighting is: when ACN detects a high level, the OUT pin outputs a high level to drive the lamp beads for emergency lighting.

[0020] This application has at least the following beneficial effects:

[0021] 1. This application adopts the master communication control mode to detect the pulse width of the synchronization signal, realizes emergency detection logic identification, is not affected by power grid disturbances and phase feet, improves the reliability of the product in practical applications, and reduces the probability of being affected by AC.

[0022] 2. In this application, when the switch is disconnected, the main control sends a square wave pulse width signal to allow the emergency device incorporated into the circuit to learn and identify, to make up for the recognition failure caused by the unrecognizable state of the sine wave phase of 0 degree and 180 degree of the neutral and live wires, to achieve synchronous control, and to use square wave signal complementary verification and pulse width recognition to improve the anti-interference ability of circuit detection.

[0023] 3. This application has been tested in actual products to support DC state emergency detection phase identification, that is, it supports AC and DC access to the grid for power supply and is not affected by grid input. It is applied to fire emergency, emergency lighting and other products, thereby improving product compatibility.

[0024] 4. This application uses Schmitt triggering to detect changes in battery input voltage under emergency conditions, and changes the emergency detection benchmark in real time to solve the sensitivity problem of power-off detection when the battery is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 A schematic diagram of multiple emergency devices connected in parallel to the same switch control loop according to an embodiment of the present application;

[0027] Figure 2 A schematic diagram of a high level output of "ACL" inside an emergency device triggering "ACN" through a parallel circuit provided by one embodiment of the present application;

[0028] Figure 3 A mixed operation flow chart of an emergency detection circuit provided for one embodiment of the present application;

[0029] Figure 4 A schematic diagram of a hybrid connection of an emergency detection circuit provided in one embodiment of the present application;

[0030] Figure 5 A timing logic diagram of a hybrid operation of an emergency detection circuit provided by an embodiment of the present application;

[0031] Figure 6 A block diagram of U2 provided for one embodiment of the present application;

[0032] Figure 7 An internal Schmitt equivalent circuit of U2 provided in one embodiment of the present application;

[0033] Figure 8 A schematic diagram of the installation of an emergency device provided in one embodiment of the present application;

[0034] Fig. 9 A flowchart of a phase synchronization detection operation provided by an embodiment of the present application;

[0035] Fig.10 A schematic diagram of the phase of the neutral and live wires and the internal detection waveform of the emergency device provided by one embodiment of the present application;

[0036] Fig.11 A schematic diagram of the basic working principle of an emergency detection circuit provided in one embodiment of the present application;

[0037] Fig.12 A schematic diagram of an emergency principle provided for an embodiment of the present application;

[0038] Fig.13 A typical application schematic diagram of an emergency lighting device provided for one embodiment of the present application;

[0039] Fig.14 A schematic diagram of the emergency detection principle provided for an embodiment of the present application. DETAILED DESCRIPTION

[0040] In order to further explain the technical means and effects adopted by the present application to achieve the predetermined invention purpose, the following is a detailed description of the high-sensitivity power failure detection method for LED emergency lighting devices proposed in the present application, its specific implementation, structure, features and effects, in combination with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0041] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0042] The specific scheme of the high-sensitivity power failure detection method for LED emergency lighting devices provided by the present application is described in detail below with reference to the accompanying drawings.

[0043] An embodiment of the present application provides a high-sensitivity power failure detection method for an LED emergency lighting device.

[0044] Specifically, the following high-sensitivity power failure detection method for an LED emergency lighting device is provided, the method comprising:

[0045] In practical applications, such as the attached Figure 1 In an application where multiple LED emergency lighting devices are connected in parallel to the same switch control loop, the input L and N phases of the LED emergency lighting devices are mixed in parallel, where L represents the live wire input and N represents the neutral wire input.

[0046] It should be noted that the LED emergency lighting device is an emergency lamp, including but not limited to a bulb lamp, a panel lamp, and a T-tube lamp. In this embodiment, the LED emergency lighting device is collectively referred to as an emergency device.

[0047] When switch K1 is disconnected, the status of "ACN" and "ACL" inside the emergency device is as shown in the attached figure. Figure 2As shown, the ACL series resistors R8 and R11, and the ACN series resistors R7 and R10 are connected to the intersection live wire and AC neutral wire circuits respectively. ACL and ACN are the AC live wire circuit output and AC neutral wire circuit output respectively. The high level output of "ACL" inside the emergency device triggers "ACN" through the parallel circuit and enters the emergency state. K1 cannot control the closing or opening of the emergency device.

[0048] In the above case, it is necessary to adjust the L and N phases of the emergency device. This embodiment adopts the "master"-"slave" communication control mode, as shown in the attached Figure 3 The mixed operation flow chart of the emergency detection circuit is shown in:

[0049] Before installing the emergency device, set the master control. Short-circuit and disconnect the L and N phases of the emergency device input 6 times within 6 seconds, which triggers the emergency light 6 times. At this time, the master control has been set. Figure 4 K1 in the figure is connected in parallel to multiple emergency devices. Only one "master" control emergency device needs to be installed, and the rest are "slave" control emergency devices.

[0050] Assuming that the input of the emergency device is in a mixed state of L and N, operate the switch K1 "on-off-on-off", and the DPL and DPN of the "master" emergency device output complementary square wave signals, among which DPN is the N phase detection signal output and DPL is the L phase detection signal output. The ACL and ACN inside the "master-slave" emergency device perform square wave pulse width signal learning and adjust the high and low level output phases of ACL and ACN.

[0051] In the attached Figure 5 In the mixed operation timing logic diagram of the emergency detection circuit, the T4-T5 timing is the learning state of the emergency device. By defining the square wave pulse duration of DPL and DPN of the main control emergency device, ACL and ACN judge whether it is the main control synchronization signal by judging the square wave pulse duration in the circuit during the learning process, thereby reducing the error in learning the phase.

[0052] Because the square wave pulses emitted by the master control DPL and DPN are complementary and have opposite phases, during the phase learning process, DPL outputs a high level for the learning process of all emergency devices, and DPN outputs a high level for the verification process of all emergency devices, thereby improving the reliability of the synchronization of detection items.

[0053] This emergency device hybrid phase synchronization solution is to achieve phase synchronization of the emergency device detection circuit without AC circuit when K1 is disconnected, thereby avoiding AC interference during the phase synchronization process. Wherein, AC is alternating current.

[0054] When K1 is disconnected, the ACL and ACN inside the "master-slave" emergency device can learn square wave pulse width signals without being affected by the power grid, and can meet the requirements of accessing the power grid in AC or DC state, thus realizing the emergency access power supply detection phase.

[0055] Attached Figure 6 The schematic diagram of U2 is shown in the figure. U2 is an emergency power management chip. The internal emergency detection circuit uses a Schmitt trigger. The internal Schmitt equivalent circuit of U2 is shown in the attached figure. Figure 7 As shown, the pull-up resistor RH and the pull-down resistor RL provide an emergency detection reference through battery power supply voltage division, and the emergency detection reference changes with the battery voltage, which is 0.51 times the battery voltage, thereby avoiding the battery voltage change affecting the emergency detection sensitivity.

[0056] In this embodiment, the application principle of the prior art is introduced, specifically:

[0057] Existing technologies such as Figure 8 , Attachment Fig. 9 And attached Fig.10 As shown, Figure 8 The emergency devices are connected in parallel in the same control circuit. In the application, the phases of the live wire L1 and the neutral wire N1 of the emergency device 1 and the emergency device 2 are opposite.

[0058] Fig. 9 The detection input and output phase adjustment of the emergency device 2 is realized through the operation of K1. The working principle is to use the phase of the neutral and live wires to determine the access phase of the emergency device, adjust the logic of the detection input and detection output of the emergency device, and make any line connected to the neutral and live wires unified as the detection input or detection output.

[0059] Fig.10 It is the phase relationship between the neutral and live wires, with a phase difference of 180 degrees. The emergency device adjusts the detection logic by judging the connection of the neutral and live wires in the switch control.

[0060] In this embodiment, the basic working principle of the emergency detection circuit is introduced, specifically:

[0061] As attached Fig.11 The basic working principle of the emergency detection circuit is shown in the schematic diagram. Fig.12 , Attachment Fig.13 , Attachment Fig.14 And attached Figure 4 Introduce the principles of emergency detection.

[0062] The emergency lighting detection circuit is composed of resistors R7, R8, R10, R11, R13, R14, R15, R16, R17, capacitor element C3, and emergency power management chip U2. BAT1 is a battery that supplies power to the emergency lighting detection circuit. T1 is a transformer. The auxiliary winding of T1, diode D2, polar capacitor EC1, and resistors R5 and R6 form a charging circuit. Among them, the auxiliary winding of T1 refers to the NS coil winding in the schematic diagram, R12 is the charging current setting, and the "OUT" pin of U2 is the discharge output.

[0063] When the "EDT" pin of U2 detects that there is no charging voltage through resistor R14, U2 enters the emergency detection state, "ACL" outputs a high level, the level voltage is the battery supply voltage, "ACN" enters the Schmitt trigger mode, and when "ACN" detects a high level, the "OUT" pin outputs a high level to drive the lamp beads "LED_4—LED3" for emergency lighting; otherwise, U2 enters the emergency detection standby state; "DPL" and "DPN" are phase-synchronized complementary square wave signal outputs; they are in a high-impedance state during emergency lighting and normal lighting.

[0064] In addition, it should be noted that all "R", "C", "EC", "U" and "BAT" etc. appearing in the drawings, after adding the number, correspond to the resistor element, capacitor element, polar capacitor, chip and battery. Among them, the electrolytic capacitor is a polar capacitor. Some symbols in the drawings that are not mentioned in the specification are well known to those skilled in the art and are not the focus of the research of this application, so no additional explanation will be given.

[0065] In one embodiment of the present application, the specific implementation method of emergency detection phase identification is as follows:

[0066] Combined with Figure 4 , Attachment Figure 6 Introduction, Attachment Figure 6 Yes Fig.11 Part of the circuit is introduced, and the internal principle block diagram of U2 is introduced. NS is the auxiliary winding of the main power supply, and it forms a charging circuit with D2 and EC2. The DET pin of U2 detects the state of K1 through R14, and the internal comparator of DET outputs the detection signal to the internal logic controller of U2. The internal logic controller of U2 outputs the control signal to the four internal circuit units A, B, C, and D; A and B are bidirectional input and output Schmitt triggers, connected to ACN and ACL respectively; C and D are bidirectional input and output latches, connected to DPN and DPL respectively.

[0067] When multiple emergency devices are connected in parallel to a K1 control loop, set any one device as the master control, and "short-circuit-disconnect" the L and N phases of the emergency device input 6 times within 6 seconds, triggering the emergency light to light up 6 times. At this time, the master control has been set.

[0068] When operating K1—close—open—close—open, as shown in the attached Figure 5 The timing diagram operation, U2 internal logic controller detects two pulse signals through the DET pin, at this time, U2 internal logic controller outputs a signal to control the C, D latches to be output state, through the DPN, DPL square wave pulse signals; A, B Schmitt triggers are input state, and the square wave pulse signal in the detection loop is fed back to the U2 internal logic controller; U2 internal logic controller outputs a control signal to adjust the ACN, ACL input and output logic, so that the emergency device connected in parallel in the K1 control loop can detect phase synchronization.

[0069] The various embodiments in the present application are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0070] It should be noted that, unless otherwise specified and limited, terms such as "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a circuit structure, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such article or device. In the absence of further restrictions, an element defined by the sentence "including one..." does not exclude the existence of other identical elements in the article or device including the element. In addition, the term "and\or" used herein includes any and all combinations of one or more related listed items.

[0071] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the invention herein. The present application is intended to cover any variations, uses or adaptations of the present application, which follow the general principles of the present application and include common knowledge or customary technical means in the art that are not invented by the present application.

[0072] It should be understood that the present application is not limited to the exact construction that has been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof.

Claims

1. A highly sensitive power failure detection method for LED emergency lighting devices, characterized in that: The method includes: Before installing the emergency circuit, set up a master control emergency device; for several emergency devices connected in parallel, use a master-slave communication control mode, set one of the emergency devices as the master control emergency device, and the others as slave control emergency devices; When the emergency device has a mixed connection state of live input L phase and neutral input N phase in parallel, operate the switch "on-off-on-off", the L phase detection signal output DPL and N phase detection signal output DPN of the master emergency device output complementary square wave signals, and the AC live circuit output ACL and AC neutral circuit output ACN inside the "master-slave" emergency device learn square wave pulse width signals, and adjust the high and low level output phases of ACL and ACN; Detect the level through the internal emergency detection circuit; The setting method of the master control emergency device is: "short-disconnect" the L and N phases of the emergency device input 6 times within 6 seconds; During the signal learning process, DPL outputs a high level for the learning process of all emergency devices, and DPN outputs a high level for the verification process of all emergency devices; The signal learning process specifically includes: presetting the square wave pulse duration of DPL and DPN of the master emergency device, and determining whether ACL and ACN are master synchronization signals by determining the square wave pulse duration in the loop during the learning process; The phase adjustment process is performed in a state where there is no AC input and the switch is disconnected.

2. The high-sensitivity power failure detection method for LED emergency lighting device according to claim 1, characterized in that: The current type in this power failure detection process includes direct current in addition to alternating current.

3. The high-sensitivity power failure detection method for LED emergency lighting device according to claim 1, characterized in that: The internal emergency detection circuit adopts a Schmitt trigger, and the pull-up resistor RH and the pull-down resistor RL provide an emergency detection reference through battery power supply voltage division.

4. The high-sensitivity power failure detection method for LED emergency lighting device according to claim 3, characterized in that: The emergency detection benchmark is 0.51 times the battery voltage.

5. The high-sensitivity power failure detection method for LED emergency lighting device according to claim 1, characterized in that: After the internal emergency detection circuit detects the level, it further determines whether to perform emergency lighting.

6. The high-sensitivity power failure detection method for LED emergency lighting device according to claim 5, characterized in that: The method for judging the emergency lighting is as follows: when ACN detects a high level, the OUT pin outputs a high level to drive the lamp beads for emergency lighting.

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