CN204350393U - Electronic type substituted type double end and straight tube LED daylight lamp and safety protective circuit thereof - Google Patents

Abstract

The utility model relates to an electronic replacement double-end straight tube LED fluorescent lamp and its safety protection circuit, wherein the safety protection circuit includes a fluorescent lamp analog cathode circuit connected to the first output end and the second output end of the electronic ballast of the fluorescent lamp; The output terminal of the analog cathode circuit is connected to the first anode of a bidirectional thyristor, and the second anode of the bidirectional thyristor is connected to the input of the high frequency rectification filter circuit of the double-ended straight tube LED fluorescent lamp through the fourth capacitor and the fifth capacitor terminal; between the control pole of the bidirectional thyristor and the output terminal of the analog cathode circuit of the fluorescent lamp, a high-frequency trigger circuit that triggers conduction at a high frequency greater than 10kHz is set; or, the control pole of the triac and the fluorescent lamp The output terminals of the tube simulation cathode circuit are in an open circuit state with distributed capacitance; the circuit settings of the third output terminal and the fourth output terminal of the electronic ballast for fluorescent lamps are symmetrical to those of the first output terminal and the second output terminal.

Description

Electronic alternative double-ended straight tube LED fluorescent lamp and its safety protection circuit

technical field

The utility model relates to the technical field of lighting, in particular to an electronic replacement double-end straight-tube LED fluorescent lamp and a safety protection circuit thereof.

Background technique

Due to its advantages of high luminous efficiency and low energy consumption, LED fluorescent tubes have gradually replaced traditional fluorescent tubes and are more and more widely used in various occasions to achieve high-efficiency lighting and energy-saving purposes. At present, the double-ended replacement LED lamp tube, which is used to directly replace the traditional fluorescent lamp tube, can be replaced without modifying the structure of the original lamp. Please refer to the patent application CN 103929858 A, which discloses an LED fluorescent tube and lighting fixture driven by a fluorescent lamp electronic ballast, in which the impedance of the fluorescent lamp filament of the fluorescent lamp electronic ballast is matched by using a high-frequency rectification filter unit , and the light is realized by the LED module, so that the LED fluorescent tube can be adapted to the electronic ballast of the fluorescent lamp to realize the purpose of lighting without improving the construction of the lamp.

According to the requirements of international IEC62776-2012 and IEC62776-2014 regulations, multiple safety tests are required for double-ended LED lamps used to replace traditional fluorescent lamps. It stipulates that when only one end of the lamp cap is inserted into the lamp holder, the electricity will be transmitted to the other end of the lamp cap that has not been inserted. At this time, no electric shock should be caused. Voltage, and only one end of the lamp holder is powered, the lamp cap at one end of the lamp tube is inserted into the lamp holder, and the lamp cap at the other end that is not inserted into the lamp holder is tested according to the requirements of IEC 60598-1 Appendix A. There is no conductive part, which will cause electric shock. In addition, it also stipulates that in accordance with the requirements of Appendix A of IEC61347-1, the insulation resistance between the pin or contact of the lamp cap and the pin or contact of the lamp cap at the other end shall not be less than 2MΩ. For insulation resistance testing, approximately 500V DC is applied in a humidity chamber. The dielectric strength test should be performed immediately after the dielectric strength test. During the dielectric strength test, the applied voltage exceeds 1500V.

However, in the LED fluorescent tube circuit scheme of the above-mentioned prior art, the rectification and filtering unit connected to the LED module is directly connected to the electronic ballast of the fluorescent lamp, without any safety protection circuit in between, so it is impossible to pass the above-mentioned double-ended LED lamp. A security test, there is a great security risk.

Utility model content

The technical problem to be solved by the utility model is to provide an electronic replacement double-ended straight tube LED fluorescent lamp and its safety protection circuit that meet the requirements of the international IEC62776-2012 and IEC62776-2014 safety regulations.

The technical scheme that the utility model solves its technical problem adopts is:

Construct an electronic alternative double-ended straight-tube LED fluorescent lamp safety protection circuit, which includes a fluorescent tube analog cathode circuit connected to the first output end and the second output end of the electronic ballast of the fluorescent lamp; wherein the fluorescent lamp analog The output terminal of the cathode circuit is connected to the first anode of a bidirectional thyristor, and the second anode of the bidirectional thyristor is connected to the high frequency rectification filter circuit of the double-ended straight tube LED fluorescent lamp through the fourth capacitor and the fifth capacitor. input terminal;

A high-frequency trigger circuit that triggers conduction at a high frequency greater than 10 kHz is provided between the control electrode of the triac and the output end of the analog cathode circuit of the fluorescent lamp;

Alternatively, the control electrode of the bidirectional thyristor and the output terminal of the analog cathode circuit of the fluorescent lamp are in an open circuit state with distributed capacitance;

The circuit arrangement of the third output terminal and the fourth output terminal of the fluorescent lamp electronic ballast is symmetrical to the circuit arrangement of the first output terminal and the second output terminal.

The safety protection circuit described in the present utility model, wherein the high-frequency trigger circuit includes a third capacitor, and the capacitance range of the third capacitor is 1P-10μF;

Alternatively, the high-frequency trigger circuit is composed of a sixth capacitor and a seventh capacitor connected in series, and the capacitance ranges of the sixth capacitor and the seventh capacitor are both 1P-10μF;

Alternatively, the high-frequency trigger circuit is composed of an eighth capacitor and a ninth resistor connected in series, the value range of the eighth capacitor is 1P-10μF, and the value range of the ninth resistor is 1Ω-10Ω;

The bidirectional thyristor is 1-5A and the withstand voltage is greater than 1KV.

The safety protection circuit described in the present invention, wherein the analog cathode circuit of the fluorescent lamp includes a first resistor connected in series between the first output end and the second output end of the electronic ballast of the fluorescent lamp and a second resistor, the two ends of the first resistor are connected in parallel with a first capacitor, and the two ends of the second resistor are connected in parallel with a second capacitor; wherein,

The connection point between the first resistor and the second resistor is the output end of the analog cathode circuit of the fluorescent lamp.

The safety protection circuit described in the present invention, wherein, the value range of the first resistor and the second resistor is 1Ω-1kΩ;

The value range of the first capacitor and the second capacitor is 0.01 μF-10 μF;

The value range of the fourth capacitor and the fifth capacitor is 0.01 μF-50 μF.

The safety protection circuit described in the utility model, wherein, the analog cathode circuit of the fluorescent lamp includes a first self-acting circuit connected in series between the first output end and the second output end of the electronic ballast of the fluorescent lamp. recovery fuse and second resettable fuse;

The connection point between the first resettable fuse and the second resettable fuse is the output end of the analog cathode circuit of the fluorescent lamp;

The value range of the current parameters of the first resettable fuse and the second resettable fuse is 0.25-2A.

The safety protection circuit described in the present invention, wherein, the safety protection circuit also includes an isolation circuit resistance channel for maintaining a small current working state of the system, including:

a third resistor connected between the first output terminal of the fluorescent lamp electronic ballast and the second anode of the triac;

a fourth resistor connected between the second output terminal of the fluorescent lamp electronic ballast and the second anode of the triac;

a fifth resistor connected in parallel to both ends of the fourth capacitor; and a sixth resistor connected in parallel to both ends of the fifth capacitor;

Wherein, the value range of the third resistor, the fourth resistor, the fifth resistor and the sixth resistor is 1MΩ-10MΩ.

The utility model also provides an electronic replacement type double-ended straight tube LED fluorescent lamp safety protection circuit, which includes a fluorescent tube analog cathode circuit connected to the first output end and the second output end of the electronic ballast of the fluorescent lamp; wherein, The output end of the analog cathode circuit of the fluorescent lamp is connected to a bidirectional thyristor group composed of at least two bidirectional thyristors connected in series and of the same type, and the bidirectional thyristor located at the front end of the bidirectional thyristor group is The first anode of the triac is connected to the output terminal of the analog cathode circuit of the fluorescent lamp, and the second anode of the triac located at the rearmost end of the bidirectional thyristor group is connected to the double-terminal straight tube through the fourth capacitor and the fifth capacitor The input end of the high-frequency rectification filter circuit of LED fluorescent lamp;

The control pole of each triac in the triac group is connected with a high-frequency trigger circuit that triggers conduction at a high frequency greater than 10kHz; wherein, the control pole of the triac at the rear end passes through The high-frequency trigger circuit is electrically connected to the control pole of the triac at the adjacent front end, and the control pole of the triac at the front end is connected to the output terminal of the analog cathode circuit of the fluorescent lamp through the high-frequency trigger circuit electrical connection;

Or, the control electrode of each triac in the triac group is in an open state with distributed capacitance between the output end of the analog cathode circuit of the fluorescent lamp;

The circuit arrangement of the third output terminal and the fourth output terminal of the fluorescent lamp electronic ballast is symmetrical to the circuit arrangement of the first output terminal and the second output terminal.

The utility model also provides an electronic replacement double-ended straight-tube LED fluorescent lamp, which is driven by a fluorescent lamp electronic ballast and includes a high-frequency rectification filter circuit connected with the LED lamp group; wherein, the fluorescent lamp electronic ballast A safety protection circuit as described in any one of the foregoing is connected between the output terminal and the high-frequency rectification and filtering circuit.

In the electronic replacement type double-ended straight tube LED fluorescent lamp described in the utility model, the high-frequency rectification and filtering circuit includes a first diode, a second diode, a third diode and a fourth diode and capacitance;

Wherein, the first diode and the second diode are connected in series through a seventh resistor or a third resettable fuse;

The third diode and the fourth diode are connected in series through a seventh first resistor or a third first resettable fuse;

The cathode of the first diode is connected to the cathode of the third diode, and the anode of the second diode is connected to the anode of the fourth diode;

The second anode of the bidirectional thyristor is connected to the connection point of the first diode and the seventh resistor through the fourth capacitor;

The second anode of the bidirectional thyristor is simultaneously connected to the connection point of the second diode and the seventh resistor through the fifth capacitor;

The capacitor is connected between the cathode of the third diode and the anode of the fourth diode;

Varistors are connected in parallel at both ends of the capacitor.

In the electronic replacement double-ended straight tube LED fluorescent lamp described in the present invention, the high-frequency rectification filter circuit is arranged in the two lamp heads of the electronic replacement double-ended straight tube LED fluorescent lamp in the form of a first module;

The safety protection circuit is set in the two lamp holders of the electronic replacement double-ended straight tube LED fluorescent lamp in the form of a second module, and the inner structures of the two lamp holders are symmetrical;

The first module in the lamp cap at one end is electrically connected to the second module through a threaded copper post, and the threaded copper post is connected to both ends of the seventh resistor, or the threaded copper post is connected to the Describe the two ends of the third resettable fuse.

The beneficial effect of the utility model is that: by setting the bidirectional thyristor between the output end of the electronic ballast of the fluorescent lamp of the electronic replacement type double-ended straight tube LED fluorescent lamp and the high-frequency rectification and filtering circuit, and the bidirectional thyristor The control electrode is connected to a high-frequency trigger circuit that triggers conduction at a high frequency greater than 10kHz, or the control electrode of the bidirectional thyristor and the output terminal of the analog cathode circuit of the fluorescent lamp are in an open circuit state with distributed capacitance, so that in At low frequency (power frequency 50/60Hz), the signal cannot trigger the triac. When it is in the state of high frequency (greater than 10k Hz), the high-frequency trigger circuit is turned on, which immediately triggers the triac, thereby turning on the electronic ballast of the fluorescent lamp. The high-frequency output current of the current regulator and the normal working channel of the LED light group play a role of safety protection.

Description of drawings

The utility model will be further described below in conjunction with accompanying drawing and embodiment, in the accompanying drawing:

Fig. 1 is a schematic diagram 1 of the safety protection circuit and related circuits of the electronic alternative double-ended straight-tube LED fluorescent lamp in a preferred embodiment of the present invention;

Fig. 2 is an electronic alternative double-ended straight tube LED fluorescent lamp safety protection circuit and related circuit schematic diagram 2 of a preferred embodiment of the present invention;

Fig. 3 is a schematic diagram 1 of a high-frequency trigger circuit in a preferred embodiment of the present invention;

Fig. 4 is the schematic diagram 2 of the high-frequency trigger circuit of the preferred embodiment of the present invention;

Fig. 5 is the safety protection circuit and related circuits of the electronic replacement type double-ended straight tube LED fluorescent lamp adopting the resettable fuse instead of the resistor in the preferred embodiment of the present invention;

Fig. 6 is another embodiment of the utility model, an electronic replacement type double-ended straight tube LED fluorescent lamp safety protection circuit and a schematic diagram of related circuits;

Fig. 7 is a schematic diagram of the internal structure of the lamp holder of the electronic replacement double-ended straight tube LED fluorescent lamp according to the preferred embodiment of the present invention.

Detailed ways

In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model, and are not intended to limit the utility model.

Figure 1 and Figure 2 show the safety protection circuit of the electronic alternative double-ended straight tube LED fluorescent lamp of the preferred embodiment of the present invention. as follows:

The electronic alternative double-ended straight-tube LED fluorescent lamp safety protection circuit includes a fluorescent tube analog cathode circuit connected to the first output end 1 and the second output end 2 of the fluorescent lamp electronic ballast 100; wherein, the output of the fluorescent lamp analog cathode circuit The terminal is connected to the first anode of a two-way thyristor SCR, and the second anode of the two-way thyristor SCR is connected to the input of the high-frequency rectification filter circuit 300 of the double-ended straight tube LED fluorescent lamp through the fourth capacitor C4 and the fifth capacitor C5 end; between the control pole of the triac SCR and the output terminal of the analog cathode circuit of the fluorescent lamp, a high-frequency trigger circuit 201 that triggers conduction at a high frequency greater than 10kHz is provided; or, the control pole of the triac There is an open circuit state with distributed capacitance between the output terminal of the analog cathode circuit of the fluorescent lamp; The circuit setup of terminal 2 is symmetrical.

The working principle of the above protection circuit is: at low frequency (power frequency 50/60Hz), the signal cannot trigger the bidirectional thyristor SCR, and when it is in the state of high frequency (greater than 10k Hz), it makes the control electrode connected to the triac SCR The high-frequency trigger circuit 201 is turned on, the conduction current is about 0.1-50mA, and the bidirectional thyristor SCR is triggered immediately. The current is introduced into the first anode of the bidirectional thyristor SCR by the fluorescent tube analog cathode circuit, and then respectively passed through the fourth capacitor C4 and the fifth capacitor C5 to the high-frequency rectification filter circuit 300 of the double-ended straight-tube LED fluorescent lamp for rectification and filtering, and then light the LED lamp group 400, thereby connecting the high-frequency output current of the fluorescent lamp electronic ballast 100 and the LED lamp group 400 to normal The working channel plays the role of safety protection.

In the above-mentioned embodiment, different from the current triggering mode in general use, the frequency triggering characteristic of the bidirectional thyristor SCR is cleverly used, and the safety protection circuit can make the dual The insulation resistance at both ends of the end LED lamp tube is greater than 2MΩ. When AC1500V, 50/60Hz voltage is applied to both ends of the lamp tube, there will be no flickering and breakdown phenomenon; at the same time, when AC500V, 50/60Hz power is applied to one end, The touch current of one end connected to the anthropometric network specified in Appendix G of IEC 60598-1 is less than 0.7mA.

In the above embodiment, as shown in Figure 2, the control electrode of the bidirectional thyristor SCR and the output terminal of the analog cathode circuit of the fluorescent lamp are in an open circuit state with distributed capacitance, specifically referring to: the control of the bidirectional thyristor SCR The pole is open-circuited without any components connected, but due to the influence of other components in the circuit, there is actually a circuit distributed capacitance between the control pole and the output end of the analog cathode circuit of the fluorescent lamp. The distributed capacitance isolates the low-frequency current, so that the signal cannot trigger the bidirectional thyristor SCR in the low-frequency state. When it is in the high-frequency (greater than 10k Hz) state, the high-frequency current immediately triggers the bidirectional thyristor SCR through the distributed capacitance, thereby turning on The high-frequency output current of the fluorescent lamp electronic ballast 100 and the normal working channel of the LED lamp group 400 play a role of safety protection.

In the above embodiments, the triac SCR is preferably a triac with a value of 1-5A and a withstand voltage greater than 1KV. Wherein, the bidirectional thyristor SCR can be regarded as composed of a PNP transistor and an NPN transistor. Therefore, a composite transistor with the same function composed of a triode with the same structure should also be within the scope of protection of the above embodiment.

In a further embodiment, as shown in FIG. 1 , the fluorescent lamp analog cathode circuit includes a first resistor R1 connected in series between the first output terminal 1 and the second output terminal 2 of the fluorescent lamp electronic ballast 100 and the second resistor R2, the two ends of the first resistor R1 are connected in parallel with the first capacitor C1, and the two ends of the second resistor R2 are connected in parallel with the second capacitor C2; wherein, the connection point between the first resistor R1 and the second resistor R2 Simulates the output of the cathode circuit for a fluorescent tube.

Preferably, the above-mentioned first resistor R1 and second resistor R2 are resistors of the same specification, and the preferred value range is 1Ω-1kΩ; the preferred value range of the first capacitor C1 and the second capacitor C2 is 0.01μF-10μF; the fourth The preferred value range of the capacitor C4 and the fifth capacitor C5 is 0.01 μF-50 μF.

In a further embodiment, as shown in FIG. 5 , the fluorescent tube analog cathode circuit includes a first self-recovery circuit connected in series between the first output terminal 1 and the second output terminal 2 of the electronic ballast 100 for fluorescent lamps. Fuse P1 and the second resettable fuse P2; the connection point between the first resettable fuse P1 and the second resettable fuse P2 is the output terminal of the analog cathode circuit of the fluorescent lamp; the first resettable fuse P1 and the second resettable fuse The value range of P2 current parameters is 0.25-2A. That is, the first resettable fuse P1 and the second resettable fuse P2 are used instead of the first resistor R1 and the second resistor R2 in the previous embodiment, and there is no need to connect the first capacitor C1 and the second capacitor C2.

Among them, the resettable fuse is composed of a polymer matrix and carbon black particles that make it conductive. Since this material has a certain conductivity, current will pass through it. When an overcurrent passes through the thermistor, the heat generated will cause it to expand, so that the carbon black particles will separate and its resistance will rise. This will cause the thermistor to heat up faster and expand more, increasing the resistance further. When the temperature reaches 125°C, the resistance changes significantly, so that the current decreases significantly. A small current through the thermistor at this point is sufficient to keep it at this temperature and in a high resistance state. When the fault is removed, the thermistor shrinks to its original shape and reconnects the carbon black particles, so that the polymer PTC thermistor cools down quickly and returns to the original low resistance state, so that it can work again in a cycle.

In a further embodiment, as shown in FIG. 1, the above-mentioned high-frequency trigger circuit 201 includes a specific third capacitor C3, one end of the third capacitor C3 is connected to the output end of the analog cathode circuit of the fluorescent lamp, and the other end is connected to the triac. The control electrode, and the preferred value range of the capacitance of the third capacitor C3 is 1P-10μF. At low frequency (power frequency 50/60Hz), the third capacitor C3 isolates the low frequency current, and the signal cannot trigger the bidirectional thyristor SCR. When it is in the high frequency (greater than 10k Hz) state, the high frequency current is triggered immediately through the third capacitor C3 The bidirectional thyristor SCR connects the high-frequency output current of the fluorescent lamp electronic ballast 100 and the normal working channel of the LED lamp group 400 to play a role of safety protection.

In a further embodiment, as shown in FIG. 3, the above-mentioned high-frequency trigger circuit 201 is composed of a sixth capacitor C6 and a seventh capacitor C7 connected in series, and the preferred value of the capacitance of the sixth capacitor C6 and the seventh capacitor C7 is The range is 1P-10μF. Similarly, at low frequency (power frequency 50/60Hz), the series circuit composed of the sixth capacitor C6 and the seventh capacitor C7 isolates the low frequency current, and the signal cannot trigger the bidirectional thyristor SCR. When it is in a high frequency (greater than 10k Hz) state , the high-frequency current passes through the sixth capacitor C6 and the seventh capacitor C7 to immediately trigger the bidirectional thyristor SCR, thereby connecting the high-frequency output current of the fluorescent lamp electronic ballast 100 and the normal working channel of the LED lamp group 400, which plays a role of safety protection .

In a further embodiment, as shown in FIG. 4, the above-mentioned high-frequency trigger circuit is composed of an eighth capacitor C8 and a ninth resistor R9 connected in series. The capacitance of the eighth capacitor C8 preferably ranges from 1P to 10 μF. The preferred value range of the nine resistors R9 is 1Ω-10Ω. Similarly, at low frequency (power frequency 50/60Hz), the series circuit composed of the eighth capacitor C8 and the ninth resistor R9 isolates the low-frequency current, and the signal cannot trigger the bidirectional thyristor SCR. When it is in a high frequency (greater than 10k Hz) state , the high-frequency current passes through the eighth capacitor C8 and the ninth resistor R9 to trigger the bidirectional thyristor SCR immediately, thereby connecting the high-frequency output current of the electronic ballast of the fluorescent lamp and the normal working channel of the LED lamp group, and playing the role of safety protection.

It can be understood that the high-frequency trigger circuit 201 in the above-mentioned embodiments can also have other conversion forms, which only need to meet the requirements of isolating the current in the low-frequency state and triggering the conduction in the high-frequency state, which will not be listed here.

In a further embodiment, the safety protection circuit 200 of the above-mentioned electronic alternative double-ended straight-tube LED fluorescent lamp also includes an isolation circuit resistance channel for maintaining a small current working state of the system, including: the first electronic ballast connected to the fluorescent lamp 100 a third resistor R3 between the output terminal 1 and the second anode of the bidirectional thyristor SCR; Four resistors R4; a fifth resistor R5 connected in parallel to both ends of the fourth capacitor C4; and a sixth resistor R6 connected in parallel to both ends of the fifth capacitor C5; wherein, the third resistor R3, the fourth resistor R4, and the fifth resistor R5 and the preferred value range of the sixth resistor R6 is 1MΩ-10MΩ.

In the low frequency state, since the bidirectional thyristor SCR is in the off state, the isolation circuit resistance channel composed of the third resistor R3, the fourth resistor R4, the fifth resistor R5 and the sixth resistor R6 with relatively large resistance can allow the system A small current flows, so as to take into account the different ignition characteristics of various types of electronic ballasts, and play a role in circuit safety protection.

As shown in Figure 6, the utility model also provides another embodiment of the safety protection circuit of the electronic replacement type double-ended straight tube LED fluorescent lamp, which includes connecting the first output terminal 1 and the second output terminal 1 of the electronic ballast 100 for fluorescent lamps. The fluorescent tube simulation cathode circuit at terminal 2; wherein, the output terminal of the fluorescent tube simulation cathode circuit is connected to a bidirectional thyristor group SCR' composed of at least two bidirectional thyristor SCRs connected in series and of the same model, and the bidirectional thyristor The first anode of the bidirectional thyristor located at the front end in the group SCR' is connected to the output end of the analog cathode circuit of the fluorescent lamp, and the second anode of the bidirectional thyristor located at the rear end in the bidirectional thyristor group SCR' passes through the fourth capacitor C4 and the fifth capacitor C5 are connected to the input end of the high-frequency rectification and filtering circuit 300 of the double-ended straight tube LED fluorescent lamp; the control pole of each bidirectional thyristor in the bidirectional thyristor group SCR' is connected with a high frequency greater than 10kHz The high-frequency trigger circuit 201 that triggers conduction under the high-frequency state; wherein, the control pole of the triac at the rear end is electrically connected with the control pole of the adjacent front-end triac through the high-frequency trigger circuit 201, and the control pole of the triac at the front end The control electrode of the bidirectional thyristor is electrically connected to the output end of the analog cathode circuit of the fluorescent lamp through the high-frequency trigger circuit 201; or, the control electrode of each triac in the triac group is connected to the analog cathode circuit of the fluorescent lamp There is an open circuit state of distributed capacitance between the output terminals of the electronic ballast for fluorescent lamps; the circuit settings of the third output terminal 3 and the fourth output terminal 4 of the electronic ballast for fluorescent lamps 100 are symmetrical to the circuit settings of the first output terminal 1 and the second output terminal 2 .

Referring to Figure 6, the working principle of the above safety protection circuit is: at low frequency (power frequency 50/60Hz), the signal cannot trigger the SCR' of the bidirectional thyristor group; The high-frequency trigger circuit 201 of the control pole of the SCR group SCR' is turned on, and the conduction current is about 0.1-50mA, which immediately triggers the SCR group SCR', and the current is introduced into the SCR group SCR by the fluorescent tube analog cathode circuit ', and then through the fourth capacitor C4 and the fifth capacitor C5 to the high-frequency rectification and filtering circuit 300 of the double-ended straight tube LED fluorescent lamp for rectification and filtering, and then light the LED lamp group 400, thereby turning on the electronic ballast of the fluorescent lamp The high-frequency output current of the current regulator 100 and the normal working channel of the LED lamp group 400 play a role of safety protection.

Since more than two (for example, two, three, four) bidirectional thyristors are connected in series to form a bidirectional thyristor group SCR', the withstand voltage performance of the protection circuit is better. During the safety standard test or during the user's installation of LED fluorescent lamps, the safety protection circuit can make the insulation resistance at both ends of the double-ended LED lamp tube greater than 2MΩ. When AC1500V, 50/60Hz voltage is applied to both ends of the lamp tube, no Flickering and breakdown phenomena; at the same time, when one end is supplied with AC500V, 50/60Hz power supply, the contact current of the other end connected to the anthropometric network specified in Appendix G of IEC 60598-1 is less than 0.7mA.

In the safety protection circuit shown in FIG. 6 , a single triac SCR in the triac group SCR' has a voltage of 1-5A and a withstand voltage greater than 1KV. Taking three triacs connected in series as an example, including the first triac at the front end, the second triac and the third triac at the rear, the second anode of the first triac The first anode of the second bidirectional thyristor is connected, and the second anode of the second bidirectional thyristor is connected to the first anode of the third bidirectional thyristor; The trigger circuit 201 is connected to the control pole of the second bidirectional thyristor; the control pole of the second bidirectional thyristor is connected to the control pole of the first bidirectional thyristor through another high-frequency trigger circuit 201; The control electrode of the bidirectional thyristor is then connected to the output end of the analog cathode circuit of the fluorescent lamp through another high-frequency trigger circuit 201 .

In the safety protection circuit shown in FIG. 6 , the high-frequency trigger circuit 201 includes a third capacitor C3, and the capacitance range of the third capacitor C3 is 1P-10 μF; or, the high-frequency trigger circuit 201 is composed of sixth capacitors connected in series Composed of C6 and the seventh capacitor C7, the capacitance ranges of the sixth capacitor C6 and the seventh capacitor C7 are both 1P-10 μF; or, the high-frequency trigger circuit 201 is composed of the eighth capacitor C8 and the ninth resistor R9 connected in series , the value range of the eighth capacitor C8 is 1P-10μF, and the value range of the ninth resistor R9 is 1Ω-10Ω. For a detailed description of the principle of the high-frequency trigger circuit 201 , please refer to the above-mentioned embodiments, which will not be repeated here.

In the safety protection circuit shown in FIG. 6 , the principle of the analog cathode circuit of the fluorescent lamp can be referred to the above-mentioned embodiments, and the parameter values of each component can also be referred to the above-mentioned embodiments, which will not be repeated here.

The electronic alternative double-ended straight tube LED fluorescent lamp safety protection circuit 200 shown in FIG. 6 further includes an isolation circuit resistance channel for maintaining the system’s low current working state. For the principle description of the isolation circuit resistance channel, please refer to The aforementioned embodiments will not be repeated here.

The utility model also provides a specific embodiment of an electronic alternative double-ended straight tube LED fluorescent lamp, as shown in Figure 7, and referring to Figures 1, 2, 3, 4, 5 and 6 at the same time, the The electronic replacement type double-ended straight-tube LED fluorescent lamp is driven by a fluorescent lamp electronic ballast 100, and includes a high-frequency rectification and filtering circuit 300 connected to the LED lamp group 400; wherein, the output terminal of the fluorescent lamp electronic ballast 100 is connected to the high-frequency rectification and filtering circuit The safety protection circuit 200 as described in any of the foregoing embodiments is connected between the circuits 300 . The safety protection circuit 200 acts as a safety switch between the output end of the electronic ballast for fluorescent lamps and the high-frequency rectification filter circuit 300, and the safety switch is a safety switch sensitive to frequency. ) state off, high frequency (greater than 10k Hz) state on. For the working principle of the safety protection circuit 200 , refer to the foregoing embodiments, which will not be repeated here.

In the electronic alternative double-ended straight-tube LED fluorescent lamp of the above embodiment, different from the current trigger mode in general use, the frequency trigger characteristic of the bidirectional thyristor SCR is cleverly used, and the safety specification test or the user installation In the process of LED fluorescent lamps, the safety protection circuit can make the insulation resistance at both ends of the double-ended LED lamp tube greater than 2MΩ. When AC1500V, 50/60Hz voltage is applied to both ends of the lamp tube, there will be no flickering and breakdown phenomena; When AC500V, 50/60Hz power is added, the contact current of the other end connected to the anthropometric network specified in Appendix G of IEC 60598-1 is less than 0.7mA.

Therefore, by adopting the electronic replacement type double-ended straight tube LED fluorescent lamp of the present utility model, no electric shock accident and damage to the lamp tube will occur during the replacement installation process and normal operation, thereby ensuring personal and property safety. At the same time, the double-ended LED fluorescent lamp can directly replace the fluorescent tube without changing the fluorescent lamp lighting circuit driven by the original electronic ballast, so as to achieve the goals of energy saving, safety, environmental protection and long-life work.

In the electronic replacement double-ended straight-tube LED fluorescent lamp of the above-mentioned embodiment, as shown in Fig. 1 and Fig. 2, the live wire terminal L and the neutral wire terminal N of the electronic ballast 100 for fluorescent lamps are connected to the AC (voltage 220V, frequency is 50Hz or 60Hz), the electronic ballast for fluorescent lamps 100 converts the AC mains AC into high-frequency AC through its internal AC-DC patented circuit and DC-AC conversion circuit, and then outputs it to the safety protection circuit 200 of the present invention. Its current frequency range is 20KHz-80KHz.

In the above-mentioned embodiment, as shown in FIG. 1 and FIG. 2 , the high-frequency rectification and filtering circuit 300 includes a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, and a capacitor Co; wherein, the first diode D1 and the second diode D2 are connected in series through the seventh resistor R7 (or the third self-recovery fuse P3, as shown in Figure 5); the third diode D3 and the fourth two Diode D4 is connected in series through the seventh first resistor R7' (or the third first self-recovery fuse P3', as shown in Figure 5); the negative pole of the first diode D1 is connected to the negative pole of the third diode D3, and the second The anode of the diode D2 is connected to the anode of the fourth diode D4; the second anode of the bidirectional thyristor SCR is connected to the connection point of the first diode D1 and the seventh resistor through the fourth capacitor C4; The second anode of the silicon SCR is connected to the connection point of the second diode D2 and the seventh resistor through the fifth capacitor C5 at the same time; the capacitor Co is connected to the cathode of the third diode D3 and the anode of the fourth diode D4 between.

Preferably, a varistor of 100V-200V is connected in parallel at both ends of the above-mentioned LED lamp group 400, so as to prevent the user from mistakenly connecting the lamp tube to the inductive fluorescent lamp, and to avoid the back electromotive force caused by the instantaneous disconnection of the starter (jump bubble). The LED lamp bead is damaged.

Preferably, in the above-mentioned electronic replacement type double-ended straight tube LED fluorescent lamp, as shown in Fig. 7, referring to Fig. 1 and Fig. In the two lamp holders 501 of the end straight tube LED fluorescent lamp; the safety protection circuit 200 is set in the two lamp holders 501 of the electronic replacement double-end straight tube LED fluorescent lamp in the form of the second module B, and the inner structures of the two lamp holders are symmetrical; The first module A and the second module B are electrically connected through a threaded copper post 504, and the threaded copper post 504 is connected to both ends of the seventh resistor R7, or the threaded copper post 504 is connected to both ends of the third resettable fuse P3 .

In the electronic alternative double-ended straight-tube LED fluorescent lamp of the above embodiment, as shown in FIG. The input end of Ln) is commonly connected to the output end of the high-frequency rectification filter circuit 300, and the output ends of a plurality of LED light emitting units (L1-Ln) are commonly connected to the loop end of the high frequency rectification filter circuit 300, and each LED light emitting unit is composed of Multiple LED chips are connected in series. Wherein, the number of multiple LED light-emitting units (L1-Ln) ranges from 2-20; in each LED light-emitting unit, the number of multiple LED chips ranges from 10-50.

The total length of the glass tube 503 of the electronic alternative double-ended straight tube LED fluorescent lamp of the above embodiment is preferably 1178mm or 1478mm, and the length of the light bar 502 is preferably 1170mm or 1466mm;

It should be understood that those skilled in the art can make improvements or changes based on the above description, and all these improvements and changes should belong to the protection scope of the appended claims of the present utility model.

Claims (10)

1. An electronic replacement type double-end straight tube LED fluorescent lamp safety protection circuit is characterized by comprising a fluorescent tube simulated cathode circuit connected to a first output end (1) and a second output end (2) of a fluorescent lamp electronic ballast (100); the output end of the fluorescent tube simulated cathode circuit is connected with a first anode of a bidirectional Silicon Controlled Rectifier (SCR), and a second anode of the bidirectional Silicon Controlled Rectifier (SCR) is connected to the input end of a high-frequency rectification filter circuit (300) of the double-end straight-tube LED fluorescent lamp through a fourth capacitor (C4) and a fifth capacitor (C5);

a high-frequency trigger circuit (201) which is triggered and conducted under the high-frequency state of more than 10kHz is arranged between the control electrode of the bidirectional Silicon Controlled Rectifier (SCR) and the output end of the fluorescent tube simulated cathode circuit;

or, an open circuit state with distributed capacitance exists between the control electrode of the bidirectional Silicon Controlled Rectifier (SCR) and the output end of the fluorescent lamp tube simulation cathode circuit;

the circuit arrangement of the third output end (3) and the fourth output end (4) of the fluorescent lamp electronic ballast (100) is symmetrical to the circuit arrangement of the first output end (1) and the second output end (2).

2. The safety protection circuit according to claim 1, wherein the high frequency trigger circuit (201) comprises a third capacitor (C3), and the capacitance of the third capacitor (C3) ranges from 1P to 10 μ F;

or the high-frequency trigger circuit (201) is composed of a sixth capacitor (C6) and a seventh capacitor (C7) which are connected in series, and the capacitance value ranges of the sixth capacitor (C6) and the seventh capacitor (C7) are both 1P-10 muF;

or the high-frequency trigger circuit (201) consists of an eighth capacitor (C8) and a ninth resistor (R9) which are connected in series, the capacitance range of the eighth capacitor (C8) is 1P-10 muF, and the value range of the ninth resistor (R9) is 1 omega-10 omega;

the bidirectional Silicon Controlled Rectifier (SCR) is 1-5A and the withstand voltage is more than 1 KV.

3. The safety protection circuit according to claim 1, wherein said fluorescent tube simulated cathode circuit comprises a first resistor (R1) and a second resistor (R2) connected in series with each other and then connected between said first output terminal (1) and said second output terminal (2) of the fluorescent lamp electronic ballast (100), a first capacitor (C1) is connected in parallel with both ends of said first resistor (R1), and a second capacitor (C2) is connected in parallel with both ends of said second resistor (R2); wherein,

the connection point between the first resistor (R1) and the second resistor (R2) is the output end of the fluorescent tube analog cathode circuit.

4. The safety protection circuit according to claim 3, wherein the first resistor (R1) and the second resistor (R2) have values in the range of 1 Ω -1k Ω;

the first capacitor (C1) and the second capacitor (C2) have the value range of 0.01-10 muF;

the value range of the fourth capacitor (C4) and the value range of the fifth capacitor (C5) are 0.01-50 muF.

5. The safety protection circuit according to claim 1, wherein said fluorescent tube simulated cathode circuit comprises a first self-recovery fuse (P1) and a second self-recovery fuse (P2) connected in series with each other between said first output terminal (1) and said second output terminal (2) of the fluorescent lamp electronic ballast;

the connection point between the first self-recovery fuse (P1) and the second self-recovery fuse (P2) is the output end of the fluorescent tube analog cathode circuit;

the current parameter ranges of the first self-recovery fuse (P1) and the second self-recovery fuse (P2) are both 0.25-2A.

6. The safety protection circuit according to claim 1, wherein the safety protection circuit (200) further comprises an isolated circuit resistive path for maintaining a low current operating state of the system, comprising:

a third resistor (R3) connected between the first output terminal (1) of the fluorescent lamp electronic ballast (100) and the second anode of the bidirectional thyristor (SCR);

a fourth resistor (R4) connected between the second output terminal (2) of the fluorescent lamp electronic ballast (100) and the second anode of the bidirectional thyristor (SCR);

a fifth resistor (R5) connected in parallel across the fourth capacitor (C4); and a sixth resistor (R6) connected in parallel across the fifth capacitor (C5);

the value ranges of the third resistor (R3), the fourth resistor (R4), the fifth resistor (R5) and the sixth resistor (R6) are 1M omega-10M omega.

7. An electronic replacement type double-end straight tube LED fluorescent lamp safety protection circuit is characterized by comprising a fluorescent tube simulated cathode circuit connected to a first output end (1) and a second output end (2) of a fluorescent lamp electronic ballast (100); the output end of the fluorescent tube simulated cathode circuit is connected with a bidirectional thyristor group (SCR ') consisting of at least two bidirectional thyristors (SCR) which are connected in series and have the same type, a first anode of the bidirectional thyristor positioned at the foremost end in the bidirectional thyristor group (SCR ') is connected with the output end of the fluorescent tube simulated cathode circuit, and a second anode of the bidirectional thyristor positioned at the rearmost end in the bidirectional thyristor group (SCR ') is connected to the input end of the high-frequency rectification filter circuit (300) of the double-end straight tube LED fluorescent lamp through a fourth capacitor (C4) and a fifth capacitor (C5);

the control electrode of each bidirectional controllable silicon in the bidirectional controllable silicon group (SCR') is connected with a high-frequency trigger circuit (201) which is triggered and conducted under the high-frequency state of more than 10 kHz; the control electrode of the bidirectional controllable silicon at the rear end is electrically connected with the control electrode of the bidirectional controllable silicon at the adjacent front end through the high-frequency trigger circuit (201), and the control electrode of the bidirectional controllable silicon at the foremost end is electrically connected with the output end of the fluorescent tube simulated cathode circuit through the high-frequency trigger circuit (201);

or, the control electrode of each bidirectional controllable silicon in the bidirectional controllable silicon group (SCR') is in an open circuit state with distributed capacitance between the control electrode and the output end of the fluorescent tube simulation cathode circuit;

the circuit arrangement of the third output end (3) and the fourth output end (4) of the fluorescent lamp electronic ballast (100) is symmetrical to the circuit arrangement of the first output end (1) and the second output end (2).

8. An electronic replacement type double-end straight tube LED fluorescent lamp is driven by a fluorescent lamp electronic ballast (100) and comprises a high-frequency rectifying and filtering circuit (300) connected with an LED lamp set (400); the fluorescent lamp electronic ballast (100) is characterized in that a safety protection circuit (200) according to any one of claims 1-7 is connected between the output end of the fluorescent lamp electronic ballast (100) and the high-frequency rectifying and filtering circuit (300).

9. The electronic replacement double-ended straight tube LED fluorescent lamp according to claim 8, wherein the high frequency rectifying and filtering circuit (300) comprises a first diode (D1), a second diode (D2), a third diode (D3) and a fourth diode (D4) and a capacitor (Co);

wherein the first diode (D1) and the second diode (D2) are connected in series by a seventh resistor (R7) or a third self-recovery fuse (P3);

the third diode (D3) and the fourth diode (D4) are connected in series through a seventh resistor (R7 ') or a third self-recovery fuse (P3');

the cathode of the first diode (D1) is connected with the cathode of the third diode (D3), and the anode of the second diode (D2) is connected with the anode of the fourth diode (D4);

a second anode of the triac (SCR) is connected to a connection point of the first diode (D1) and the seventh resistor (R7) through the fourth capacitor (C4);

a second anode of the triac (SCR) is connected to a connection point of the second diode (D2) and the seventh resistor (R7) through the fifth capacitor (C5) at the same time;

the capacitor (Co) is connected between the cathode of the third diode (D3) and the anode of the fourth diode (D4);

and both ends of the capacitor (Co) are connected with a piezoresistor (R8) in parallel.

10. The electronic replacement type double-end straight tube LED fluorescent lamp as claimed in claim 9, wherein the high-frequency rectifying and filtering circuit (300) is arranged in two lamp caps (501) of the electronic replacement type double-end straight tube LED fluorescent lamp in a first module (A) manner;

the safety protection circuit (200) is arranged in the two lamp caps (501) of the electronic replacement type double-end straight tube LED fluorescent lamp in the form of a second module (B), and the two lamp caps (501) are symmetrical in structure;

the first module (A) and the second module (B) in the lamp cap (501) at one end are electrically connected through a threaded copper column (504), the threaded copper column (504) is connected to two ends of the seventh resistor (R7), or the threaded copper column (504) is connected to two ends of the third self-recovery fuse (P3).