WO2019033237A1 - Electric leakage protection circuit, electric leakage protection apparatus and led apparatus - Google Patents

Abstract

Disclosed are an electric leakage protection circuit, an electric leakage protection apparatus and an LED apparatus. The electric leakage protection circuit comprises: a power module (101) for providing an alternating-current signal; a rectification module (102) for rectifying the alternating-current signal into a direct-current signal; a bridge arm module (103) connected to an output end of the rectification module and the power module and used for receiving the alternating-current signal and rectifying same; a voltage circuit module (107) connected to an output end of the bridge arm module and used for forming a power signal circuit; a current detection module (104) connected to the rectification module and used for carrying out current detection on the direct-current signal and obtaining a current value; a voltage sampling module (105) connected to the current detection module and used for carrying out voltage sampling on the direct-current signal and obtaining a voltage value; and an electric leakage protection module (108) for controlling, according to whether the current value exceeds a pre-set threshold value and whether the voltage value exceeds a pre-set value, the switching on and off of the power signal circuit. The electric leakage protection circuit, the electric leakage protection apparatus and the LED apparatus realise the effect of single-end power supply as well as dual-end power supply, without carrying out power failure protection using a mechanical switch, and same have a simple circuit structure, are relatively low in cost and reduce the power consumption.

Description

 Leakage protection circuit, leakage protection device and LED device

 [0001] This solution belongs to the technical field of electronic circuits, and particularly relates to a leakage protection circuit, a leakage protection device, and an LED device.

 Background technique

 [0002] At present, for a leakage protection control circuit, which can be used to drive an LED tube, and the LED tube driving circuit on the market mainly includes a buck conversion circuit (BUCK driving circuit) and a buck-boost type circuit (BUC K- BOOST drive circuit) However, the above leakage protection control circuit can only be single-ended and cannot be double-ended. The application can not be directly installed in some lamps, and the circuit needs to be modified to meet the requirements. It is unable to achieve double-ended power input. If the leakage current test of the UL1993 standard is met (the leakage current limit is 5 mA in the case of 277V 60Hz), it is necessary to add a safety switch (mechanical switch) to the lamp. The cost of the method is high, the installation is inconvenient, and the number of mechanical resets is limited.

 [0003] Therefore, the existing leakage protection technology has the problem that double-ended power input cannot be realized and mechanical shutdown is required for power-off protection.

 technical problem

 [0004] The purpose of the present solution is to provide a leakage protection circuit, a leakage protection device, and an LED device, which are intended to solve the problem that the existing leakage protection technology cannot achieve double-ended power input and requires mechanical shutdown to perform power-off protection. .

 Problem solution

 Technical solution

 [0005] A first aspect of the present invention provides a leakage protection circuit, where the leakage protection circuit includes:

 a power supply module for providing an alternating current signal;

 a rectifying module for rectifying the alternating current signal into a direct current signal;

 [0008] connected to the output end of the rectifier module and the power module, for receiving the alternating current signal and rectifying the bridge arm module;

[0009] connected to the output end of the bridge arm module, a voltage loop module for forming a power signal loop; [0010] a current detecting module connected to the rectifier module for performing current detection on the direct current signal and obtaining a current value;

 [0011] a voltage sampling module connected to the current detecting module for performing voltage sampling on the direct current signal and obtaining a voltage value;

 [0012] a case for determining whether the current value exceeds a preset threshold and whether the voltage value exceeds a preset value

And a leakage protection module that controls the power signal loop to be turned on and off.

[0013] In a second aspect of the present invention, a leakage protection device is provided, and the leakage protection device includes the above-described leakage protection circuit.

 [0014] The third aspect of the present invention provides an LED device, where the LED device includes a buck conversion circuit, and LE

The D lamp and the leakage protection circuit as described above, wherein the electric signal outputted by the leakage protection circuit is decompressed by the voltage reduction conversion circuit to drive the LED lamp to emit light.

[0015] A fourth aspect of the present invention provides an LED device, where the LED device includes a buck-boost type circuit, an LED lamp, and a leakage protection circuit as described above, and an electrical signal output by the leakage protection circuit passes through the riser The step-down type circuit performs voltage conversion to drive the LED tube to emit light.

 Advantageous effects of the invention

 Beneficial effect

 [0016] The solution provides a leakage protection circuit, a leakage protection device, and an LED device. The AC signal is rectified by adding a bridge arm module, and the current value is obtained by the current detection module and the voltage value is obtained by the voltage sampling module. The leakage protection module controls the power signal loop to be turned on and off according to whether the current value exceeds a preset threshold and whether the voltage value exceeds a preset value. This achieves the effect of single-ended power input or double-ended power input, eliminating the need for mechanical shutdown for power-off protection, and has a simple circuit structure, low cost, and reduced power consumption, thus solving the existing leakage current. Protection technology has the problem of not being able to achieve double-ended power input and requiring mechanical shutdown for power-off protection.

 Brief description of the drawing

 DRAWINGS

 1 is a schematic structural diagram of a module of a leakage protection circuit provided by the present scheme.

2 is a circuit diagram showing an example of a leakage protection circuit provided by the present scheme.

[0019] FIG. 3 is a schematic diagram showing the internal unit structure of the leakage protection chip U2 in the leakage protection circuit provided by the present scheme. Figure.

 4 is a schematic diagram showing the internal circuit connection structure of the leakage protection chip U2 in the leakage protection circuit provided by the present scheme.

Embodiments of the invention

 [0022] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present solution more clear, the present embodiment will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to be limiting.

[0022] The solution provides a leakage protection circuit, a leakage protection device and an LED device, and increases the bridge arm module to rectify the alternating current signal, and obtains the current value through the current detection module and the voltage sampling module to obtain the voltage value, so as to protect the leakage The module controls the power signal loop to be turned on and off according to whether the current value exceeds a preset threshold and whether the voltage value exceeds a preset value.

[0023] In order to explain the technical solutions described in the present solution, the following description will be made by way of specific embodiments.

[0024] FIG. 1 shows a module structure of a leakage protection circuit provided by the present solution. For the convenience of description, only parts related to the embodiment of the present solution are shown, which are as follows:

 [0025] The above leakage protection circuit includes a power module 101, a rectifier module 102, a bridge arm module 103, a voltage loop module 107, a current detecting module 104, a voltage sampling module 105, and a leakage protection module 108.

 The power module 101 is configured to provide an alternating current signal; the rectifier module 102 is configured to rectify the alternating current signal into a direct current signal; the bridge arm module 103 is connected to the output end of the rectifier module 102 and the power module 101 for receiving alternating current The signal is rectified; the voltage loop module 107 is connected to the output end of the bridge arm module 103 for forming a power signal loop; the current detecting module 104 is connected to the rectifier module 102 for current detection of the DC signal and The current sampling value is connected to the current detecting module 104 for voltage sampling of the direct current signal and obtaining a voltage value. The leakage protection module 108 is configured to determine whether the current value exceeds a preset threshold and whether the voltage value exceeds a preset value. In the case of the control, the power signal loop is turned on and off.

 [0027] wherein, when the current value exceeds a preset threshold and the voltage value exceeds a preset value 吋, the leakage protection module 108 controls the power signal loop to be turned off to provide power-off protection; otherwise, the control power signal loop is turned on.

, make it work properly. [0028] As an embodiment of the present invention, the leakage protection circuit further includes an oscillation module 106. The oscillation module 106 is connected to the voltage sampling module 105 and the leakage protection module 108 for performing signal oscillation on the DC signal.

 [0029] As an embodiment of the present invention, the leakage protection circuit can further drive the LED lamp through the buck conversion circuit or the buck-boost circuit, so that the double-ended power can be realized without mechanical safety. Installation of an LED lamp to replace the fluorescent lamp caused by electric shock or other accidents.

 [0030] FIG. 2 shows an example circuit of a leakage protection circuit provided by the present solution. For convenience of description, only parts related to the embodiment of the present solution are shown, which are as follows:

 [0031] As an embodiment of the present invention, the power module 101 is an AC power source having a fixed voltage value, and has a voltage value of 100V to 220V.

 [0032] As an embodiment of the present solution, the rectifier module 102 includes a rectifier bridge BD1. The first output end of the rectifier bridge BD1 is grounded, and the second output end of the rectifier bridge BD1 is an output end of the rectifier module 102. The first input end of the rectifier bridge BD1 is connected to the L terminal (hot line) of the AC power supply through the fuse F1, and the second input end of the rectifier bridge BD1 is connected to one of the N terminals (neutral line) of the AC power source through the ninth resistor R22.

 [0033] As an embodiment of the present solution, the bridge arm module 103 includes a first diode D3 and a second diode D4; an anode of the second diode D4 is grounded, and a cathode of the second diode D4 is The anode of a diode D3 is commonly connected and serves as the input of the bridge arm module 103. The cathode of the first diode D3 is the output of the bridge arm module 103. The cathode of the second diode D4 is connected to the anode of the first diode D3 to another N terminal (zero line) of the alternating current power source, and the anode of the second diode D4 is further connected to the first end of the varistor RV1. Connected, the cathode of the first diode D 3 is also connected to the second end of the varistor RV1. Therefore, one L terminal (one fire wire) and two N terminals (two neutral wires) of the AC power supply allow it to be single-ended or double-ended.

 [0034] As an embodiment of the present solution, the voltage loop module 107 includes a first resistor R12, a second resistor R13, and a first capacitor C9. The first end of the first resistor R12 is an input end of the voltage loop module 107. The second end of the resistor R12 is connected to the first end of the second resistor R13, the second end of the second resistor R13 is connected to the first end of the first capacitor C9, and the second end of the first capacitor C9 is grounded.

[0035] As an embodiment of the present solution, the current detecting module 104 includes a fourth capacitor C13, a seventh resistor R18, and an eighth resistor R19; a first end of the fourth capacitor C13 and a first end of the seventh resistor R18 and The first end of the eight resistor R19 is commonly connected and serves as an input terminal of the current detecting module 104, and the second end of the fourth capacitor C13 is The second end of the seventh resistor R18 and the second end of the eighth resistor R19 are commonly connected and serve as an output of the current detecting module 104.

 [0036] As an embodiment of the present solution, the voltage collecting module 105 includes a sixth resistor R17, a ninth resistor R22, and a second capacitor C11; a first end of the sixth resistor R17 and a first end of the ninth resistor R22 and The first end of the second capacitor C11 is connected to the second end of the second capacitor C11, and the second end of the sixth resistor R17 is connected to the second end of the eighth resistor R19.

 [0037] As an embodiment of the present embodiment, the oscillating module 106 includes a third resistor R14, a fourth resistor R15, a fifth resistor R16, and a third capacitor C12. The first terminal of the fifth resistor R16 is connected to the third capacitor C12. The second end of the fifth resistor R16 is connected to the first end of the third resistor R14 and the first end of the fourth resistor R15, and the second end of the third capacitor C12 is connected to the second end of the fourth resistor R15.

 [0038] As an embodiment of the present solution, the leakage protection module 108 includes a leakage protection chip U2, a reset terminal RST of the leakage protection chip U2, an oscillation terminal CT, a voltage detection terminal VS, a current detection terminal CS, and a first reference terminal DRN1. The second reference terminal DRN2, the ground terminal GND, and the power terminal VCC are respectively a reset end of the leakage protection module 108, an oscillating terminal, a voltage detecting terminal, a current detecting terminal, a first reference terminal, a second reference terminal, a ground terminal, and a power supply. end. In the present embodiment, the leakage protection chip U2 is a leakage protection chip of the type LT2200. Of course, the type of the leakage protection chip is not limited as long as it can achieve the function described in the leakage protection chip U2 of the embodiment.

 [0039] The solution also provides a leakage protection device, which includes the above leakage protection circuit

[0040] The solution further provides an LED device, comprising a buck conversion circuit, an LED lamp tube, and a leakage protection circuit as described above, wherein the electric signal output by the leakage protection circuit is decompressed by the buck conversion circuit to drive the LED The lamp is illuminated. Among them, the buck conversion circuit is a BUCK drive circuit which is common in the prior art.

 [0041] The solution further provides an LED device, comprising a buck-boost type circuit, an LED lamp tube, and a leakage protection circuit as described above, wherein the electric signal outputted by the leakage protection circuit is subjected to voltage conversion by a buck-boost type circuit to drive the LED The lamp is illuminated. Among them, the buck-boost type circuit is a BUCK-BOOST drive circuit which is common in the prior art.

[0042] FIG. 3 shows the internal unit structure of the leakage protection chip U2 in the leakage protection circuit provided by the present solution. For the convenience of description, only the parts related to the embodiment of the present solution are shown, which are as follows: [0043] As an embodiment of the present invention, the leakage protection chip U2 includes a power-on activation unit 1081, a zero-cross detection unit 1082, a high-power drive MOS unit 108, a field effect transistor 1084, a voltage sampling unit 1085, and an oscillation circuit control unit 1086. , abnormal protection reset unit 1087, ground detection loop unit 1088, NAND gate control logic unit 1090, drive unit 1091 and over temperature protection unit 1089;

 [0044] The power-on starting unit 1081 is connected to the power terminal VCC for starting the operation of the entire leakage protection chip U2; the zero-crossing detecting unit 1082 is connected to the voltage detecting terminal VS for converting the waveform from the positive half cycle to the negative half cycle, passing through zero The high-power driving MOS unit 1083 is connected to the first reference terminal DRN1 and the second reference terminal D RN2 for driving the internal FET 1084 (shown by MOS in FIG. 3); the voltage sampling unit 1085 is connected. The current detecting terminal CS is used for sampling the voltage signal; the oscillation circuit control unit 1086 is connected to the oscillating terminal CT for oscillating the received electrical signal; the abnormal protection reset unit 1087 is connected to the reset terminal RST for the leakage protection chip U2 performs a reset operation; the ground detection loop unit 1088 is connected to the ground GND for detecting the ground loop; the over-temperature protection unit 1089 is connected to the power-on starting unit 1 081 for over-temperature protection; The NOT gate control logic unit 1090 and the zero-crossing detection unit 1082, the voltage sampling unit 1085, and the oscillation loop control unit 1086 are used. Logic processing the electrical signal; a driving unit 1091 and NAND gate 1090 control logic unit, the reset unit 1087 and abnormality protection FET 1084 is connected, for outputting a drive signal to the FET 1084.

 [0045] FIG. 4 shows an internal circuit connection structure of the leakage protection chip U2 in the leakage protection circuit provided by the present solution, and the above-mentioned leakage protection circuit, leakage protection device and LED device are combined with FIG. 1 to FIG. The working principle is explained as follows:

 [0046] 1 leakage current detection protection: It simulates the body resistance electric shock network. When the power is turned on, the internal power-on starting unit 1081 of the leakage protection chip U2 starts to start, and the leakage protection chip U2 (the following IC can be used instead) Check whether the GND loop is normal, check whether the GND loop current is in the normal range, and self-test operation for 100ms. Perform self-test. Internal FET MOS is normally connected. GND1 of the subsequent stage and the front rectifier bridge BD1 are connected to the circuit. Start working normally.

 [0047] 2 When the human body is hit by electricity, it is equivalent to the human body impedance of the earth line with leakage current (resistance value is 500 ohms - 2K ohms)

), when the circuit is connected to a 500 ohm resistor, the current of the GND loop becomes smaller, and the voltage sampling of the PIN 3 of the leakage protection chip U2 is connected to the sixth resistor R17, and the voltage is instantaneously increased by the internal operational amplifier, and the comparison voltage is 0.3V. When greater than 0.3V, the comparator outputs a high level and enters the control logic gate. By the right and wrong The digital logic circuit converts, and the NAND gate outputs a high-level control thyristor to lock the Vref NAND gate output to a low-level MOS transistor to turn off. Turning off the GND of the previous and subsequent stages is equivalent to starting the leakage protection. Of course, this kind of control method is only applicable to the grid and the mains. For example, the AC power from the autotransformer cannot be used. The impedance is too large. The IC defaults to the resistance of the human body, and the IC is turned off.

[0048] 3 reset control loop: realized by the third capacitor C12 (ie, bypass capacitor), and the third capacitor C12 is charged and discharged. IC built-in counting one-stable circuit, its function is to delay, debounce, and divide

) Frequency and pulse output. The circuit works normally. The reset loop continuously monitors whether the loop is normal. The power-down monitoring oscillation frequency is 10-15KH. The power-off time between the power-down and the IC-off time is less than 100ms, which is very short, which can prevent electric shock caused by misoperation during installation. The charge and discharge are realized by the VCC loop, and the output is ON LOW and low impedance to ground. When the output is OFF, it is HIGH, and the ground is high impedance. When the PIN3 voltage has been more than 0.3V吋, the reset circuit is in the locked state, and the GND loop current is detected to increase, meeting the startup requirement. The reset circuit sends a 5V high level to the logic operator, and the operator issues a high-potential circuit lock. , MOS turn-on reset is complete.

 [0049] 4 zero-crossing detection loop: When the alternating current waveform is converted from the positive half cycle to the negative half cycle, the detection by the zero-bit system, the rectified pulsating DC is monitored and the waveform is compared, the waveform variation, the frequency and the induced voltage. Can be calculated through the logic gate circuit. Therefore, the effective control of the leakage and shutdown of the leakage loop prevents the use of 吋 ICs in the complex grids with large interferences.

 [0050] 5 over-temperature protection control is completed by the IC logic gate circuit, the operating temperature range is between -35 degrees and 105 degrees, the resistance value of the IC built-in PTC resistor and the temperature change curve, VCC takes power, after the resistor is divided The IC is turned off by the logic gate circuit. After the temperature drop range, the IC reset is performed by the reset control loop.

 Therefore, the leakage protection circuit, the leakage protection device and the LED device provided by the embodiment have the advantages of:

 [0052] 1. The first diode D3 and the second diode D4 are used to add a bridge arm to realize AC double-ended power feeding, and AC single-ended power is also realized;

 [0053] 2. The control logic mode of the IC of the pre-stage detects the leakage current, simulates the impedance of the human body to control the electronic 幵 concern, and replaces the GND circuit to make the latter stage not work, etc.;

[0054] 3, the front stage IC output terminal connected to any circuit does not affect the operation of the leakage current IC;

[0055] 4. The FET MOS directly controls the GND processing leakage protection of the front stage and the rear stage, compared with the conventional air leakage. Electricity is more intelligent;

 [0056] 5. Zero-crossing detection prevents IC malfunction.

 [0057] In summary, the embodiment of the present invention provides a leakage protection circuit, a leakage protection device, and an LED device. The AC signal is rectified by adding a bridge arm module, and the current value and the voltage sampling are obtained by the current detection module. The module obtains the voltage value, so that the leakage protection module controls the power signal loop to be turned on and off according to whether the current value exceeds a preset threshold and whether the voltage value exceeds a preset value. This achieves the effect of single-ended power input or double-ended power input, eliminating the need for mechanical shutdown for power-off protection, and has a simple circuit structure, low cost, and reduced power consumption, thus solving the existing leakage current. Protection technology has the problem of not being able to achieve double-ended power input and requiring mechanical shutdown for power-off protection. The embodiment of the solution is simple in implementation, does not require additional hardware, can effectively reduce costs, and has strong ease of use and practicability.

 The above description is only for the preferred embodiment of the present invention, and is not intended to limit the present solution. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention should be included in the present disclosure. Within the scope of protection of the program.

Claims

Claim A leakage protection circuit, characterized in that: the leakage protection circuit comprises: a power supply module for providing an alternating current signal; a rectifying module for rectifying the alternating current signal into a direct current signal; Connected to an output end of the rectifier module and the power module, and configured to receive the AC signal and rectify the bridge arm module; And a voltage loop module for forming a power signal loop connected to an output end of the bridge arm module; a current detecting module connected to the rectifier module for performing current detection on the direct current signal and obtaining a current value; And a voltage sampling module connected to the current detecting module for performing voltage sampling on the direct current signal and obtaining a voltage value; And a leakage protection module for controlling the power signal loop to be turned on and off according to whether the current value exceeds a preset threshold and whether the voltage value exceeds a preset value. The leakage protection circuit of claim 1, wherein the leakage protection circuit further comprises: And an oscillating module for oscillating the DC signal with the voltage sampling module and the leakage protection module. The leakage protection circuit of claim 1 wherein said rectifier module comprises a rectifier bridge. The first output end of the rectifier bridge is grounded, and the second output end of the rectifier bridge is an output end of the rectifier module. The leakage protection circuit according to claim 1, wherein the bridge arm module comprises a first diode and a second diode; An anode of the second diode is grounded, a cathode of the second diode is coupled to an anode of the first diode and serves as an input end of the bridge arm module, the first diode The cathode is the output of the bridge arm module. The leakage protection circuit of claim 1 wherein said voltage loop module comprises:  a first resistor, a second resistor, and a first capacitor;  The first end of the first resistor is an input end of the voltage loop module, the second end of the first resistor is connected to the first end of the second resistor, and the second end of the second resistor is connected to the second end The first end of the first capacitor is described.  The leakage protection circuit of claim 1, wherein the current detection module comprises:  a fourth capacitor, a seventh resistor, and an eighth resistor;  The first end of the fourth capacitor is coupled to the first end of the seventh resistor and the first end of the eighth resistor and serves as an input end of the current detecting module, and a second end of the fourth capacitor The terminal is coupled to the second end of the seventh resistor and the second end of the eighth resistor and serves as an output of the current detecting module.  The leakage protection circuit of claim 1, wherein the voltage collection module comprises:  a sixth resistor, a ninth resistor, and a second capacitor;  The first end of the sixth resistor is connected to the first end of the ninth resistor and the first end of the second capacitor, and the second end of the ninth resistor is connected to the second end of the second capacitor end. The leakage protection circuit according to claim 2, wherein the oscillation module comprises a third resistor, a fourth resistor, a fifth resistor, and a third capacitor; and the first end of the fifth resistor is connected to the third a first end of the capacitor, a second end of the fifth resistor, a first end of the third resistor, and a first end of the fourth resistor, and a second end of the third capacitor is connected to the fourth end The second end of the resistor.  [Claim 9] The leakage protection circuit according to claim 1, wherein the leakage protection module comprises a leakage protection chip. The reset end, the oscillating end, the voltage detecting end, the current detecting end, the first reference end, the second reference end, the ground end, and the power end of the leakage protection chip are respectively the leakage protection module The reset terminal, the oscillating terminal, the voltage detecting terminal, the current detecting terminal, the first reference terminal, the second reference terminal, the ground terminal, and the power terminal.  [Claim 10] A leakage protection device, characterized in that the leakage protection device comprises the leakage protection circuit according to any one of claims 1-9. [Claim 11] An LED device, wherein the LED device includes a buck conversion circuit, L  The ED lamp and the leakage protection circuit according to any one of claims 1 to 9, wherein the electric signal output from the leakage protection circuit is decompressed by the buck converter circuit to drive the LED lamp to emit light.  [Claim 12] An LED device, comprising: a buck-boost type circuit, an LED lamp, and a leakage protection circuit according to any one of claims 1-9, wherein the leakage protection The electrical signal outputted by the circuit is driven by the buck-boost type circuit to drive the LED lamp to emit light.