阅读说明：本技术 一种超高压光电耦合器和数字信号系统 (Ultrahigh voltage photoelectric coupler and digital signal system ) 是由 李兴冀 杨剑群 吕钢 于 2020-07-28 设计创作，主要内容包括：本发明提供了一种超高压光电耦合器和数字信号系统,涉及光电学元件技术领域。所述超高压光电耦合器包括发射端、可见光纤、接收端以及光电流调理电路,所述发射端用于将输入的电信号转换为光信号,所述可见光纤作为传输介质,用于传输所述发射器发射的光信号,所述可见光纤的一端与所述发射端连接；所述接收端用于接收所述可见光纤传输的光信号,所述可见光纤的另一端与所述接收端连接；所述光电流调理电路用于对所述接收端接收到的信号进行修正。这样,通过所述发射端、所述可见光纤、所述接收端以及所述光电流调理电路的配合,以实现10KV耐压的超高压光电耦合器。(The invention provides an ultrahigh voltage photoelectric coupler and a digital signal system, and relates to the technical field of photoelectric elements. The ultrahigh-voltage photoelectric coupler comprises a transmitting end, a visible optical fiber, a receiving end and a photocurrent conditioning circuit, wherein the transmitting end is used for converting an input electric signal into an optical signal, the visible optical fiber is used as a transmission medium and is used for transmitting the optical signal transmitted by the transmitter, and one end of the visible optical fiber is connected with the transmitting end; the receiving end is used for receiving the optical signal transmitted by the visible optical fiber, and the other end of the visible optical fiber is connected with the receiving end; the photocurrent conditioning circuit is used for correcting the signal received by the receiving end. Therefore, the 10KV voltage-resistant ultrahigh voltage photoelectric coupler is realized through the matching of the transmitting end, the visible optical fiber, the receiving end and the photocurrent conditioning circuit.)

1. An ultrahigh-voltage photocoupler, comprising:

a transmitting terminal (1) for converting an input electrical signal into an optical signal;

the visible optical fiber (2) is used as a transmission medium and is used for transmitting the optical signal transmitted by the transmitting end (1), and one end of the visible optical fiber (2) is connected with the transmitting end (1);

the receiving end (3) is used for receiving the optical signal transmitted by the visible optical fiber (2), and the other end of the visible optical fiber (2) is connected with the receiving end (3); and

and the photocurrent conditioning circuit (4) is used for correcting the signal received by the receiving end (3).

2. The ultrahigh-voltage photocoupler according to claim 1, wherein the wavelength band of the output optical signal of the transmitting terminal (1) is a red wavelength band.

3. The ultrahigh-voltage photocoupler according to claim 1 or 2, wherein the receiving terminal (3) includes a photodiode whose wavelength band matches that of the optical signal output from the transmitting terminal (1).

4. The ultrahigh-voltage photocoupler according to claim 3, wherein the photocurrent conditioning circuit (4) includes:

an input bias module (6) for generating a leakage current;

an amplifying module (7) for amplifying the leakage current generated by the input biasing module (6); and

and the output bias module (8) is used for converting the leakage current into a voltage signal so as to output a digital signal.

5. The ultrahigh-voltage photocoupler according to claim 4, wherein the input bias module (6) comprises a first bias resistor (R1), one end of the first bias resistor (R1) is connected with the positive electrode of the photodiode (D2), and the other end of the first bias resistor (R1) is grounded;

the amplifying module (7) comprises a transistor (Q1), the base of the transistor (Q1) is connected with one end of the first bias resistor (R1), the base of the transistor (Q1) is connected with the anode of the photosensitive diode (D2), and the emitter of the transistor (Q1) is grounded;

the output bias module (8) comprises a second bias resistor (R2), one end of the second bias resistor (R2) is connected with the cathode of the photosensitive diode (D2), and the other end of the second bias resistor (R2) is connected with the collector of the photosensitive diode (D2).

6. The ultrahigh-voltage photocoupler according to claim 5, wherein the photo-electric conditioning circuit (4) further comprises a lead compensation capacitor (C1) for leading the phase of the collector of the transistor (Q1), one end of the lead compensation capacitor (C1) being connected to the cathode of the photodiode (D2) and the other end being connected to the collector of the transistor (Q1).

7. The ultrahigh-voltage photoelectric coupler according to claim 6, wherein the photoelectric conditioning circuit (4) further comprises a decoupling capacitor (C2) for reducing the interference of the fluctuation of the power supply voltage to the leakage current, and one end of the decoupling capacitor (C2) is connected with the power supply voltage, and the other end is grounded.

8. The ultrahigh-voltage photocoupler according to claim 1, wherein the visible fiber (2) has a length ranging from 8mm to 24 mm.

9. The ultrahigh-voltage photocoupler according to claim 1, wherein the visible optical fiber (2) is made of teflon.

10. A digital signal system comprising an ultra high voltage photocoupler according to any one of claims 1 to 9.

Technical Field

The invention relates to the technical field of photoelectric elements, in particular to an ultrahigh voltage photoelectric coupler and a digital signal system.

Background

The photoelectric coupler is an electric-optical-electric converter for transmitting electric signal by using light as medium, and is formed from two portions of light-emitting device and light-receiving device, and the light-emitting device and light-receiving device are assembled in the same closed shell body, and are mutually filled and isolated by using light-transmitting insulator. The electrical signal is converted into an optical signal by the light emitting element, and the optical signal is received by the light receiving element and converted into the electrical signal.

The conventional photoelectric coupler is realized by adopting an infrared spectrum and an air cavity and is packaged inside a chip, but the loss of the infrared spectrum in the air cavity is very large, the space of the air cavity is limited, the withstand voltage of the conventional photoelectric coupler can only achieve six-seven kilovolts at present, and the insulating property of the photoelectric coupler in an isolation application occasion exceeding 10KV cannot be met.

Disclosure of Invention

The invention solves the problem that the existing photoelectric coupler can not meet the withstand voltage exceeding 10 KV.

In order to solve the above problems, the present invention provides an ultrahigh voltage photoelectric coupler, comprising:

the transmitting terminal is used for converting the input electric signal into an optical signal;

the visible optical fiber is used as a transmission medium and is used for transmitting the optical signal emitted by the emitting end, and one end of the visible optical fiber is connected with the emitting end;

the receiving end is used for receiving the optical signal transmitted by the visible optical fiber, and the other end of the visible optical fiber is connected with the receiving end; and

and the photocurrent conditioning circuit is used for correcting the signal received by the receiving end.

This application has increased visible fiber and photocurrent conditioning circuit for setting up of conventional optoelectronic coupler newly, because visible fiber has good super high withstand voltage characteristic, keep apart the transmission as the medium of propagation light through setting up visible fiber, through the withstand voltage characteristic of adjustment optic fibre in order to control transmitting terminal and receiving terminal, through the correction of photoelectric current circuit, thereby make the receiving effect of receiving terminal best, thereby the withstand voltage that realizes between the transmitting terminal and the receiving terminal of optoelectronic coupler can exceed 10 KV.

Optionally, the wavelength band of the optical signal output by the transmitting end is a red light wavelength band.

Optionally, the receiving end includes a photodiode, and a wavelength band of the photodiode matches a wavelength band of the optical signal output by the transmitting end.

Optionally, the photocurrent conditioning circuit comprises:

an input bias module for generating a leakage current;

the amplifying module is used for amplifying the leakage current generated by the input biasing module; and

and the output bias module is used for converting the leakage current into a voltage signal so as to output a digital signal.

Optionally, the input bias module includes a first bias resistor, one end of the first bias resistor is connected to the anode of the photodiode, and the other end of the first bias resistor is grounded;

the amplifying module comprises a transistor, the base electrode of the transistor is connected with one end of the first bias resistor, the base electrode of the transistor is connected with the anode of the photosensitive diode, and the emitter electrode of the transistor is grounded;

the output bias module comprises a second bias resistor, one end of the second bias resistor is connected with the negative electrode of the photosensitive diode, and the other end of the second bias resistor is connected with the collector electrode of the photosensitive diode.

Optionally, the photoelectric conditioning circuit further includes a leading compensation capacitor for leading a phase of a collector of the transistor, and one end of the leading compensation capacitor is connected to a cathode of the photodiode, and the other end of the leading compensation capacitor is connected to the collector of the transistor.

Optionally, the photoelectric conditioning circuit further includes a decoupling capacitor for reducing interference of fluctuation of a power supply voltage to the leakage current, one end of the decoupling capacitor is connected to the power supply voltage, and the other end of the decoupling capacitor is grounded.

Optionally, the visible optical fiber has a length ranging between 8mm and 24 mm.

Optionally, the material of the visible light fiber is a teflon material.

As another embodiment of the present invention, the present invention discloses a digital signal system, including the above-mentioned ultrahigh voltage photocoupler.

The digital signal system and the ultrahigh voltage photoelectric coupler have the same beneficial effects on the prior art, and are not described again here.

Drawings

Fig. 1 is a schematic structural diagram of an ultrahigh voltage photocoupler according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a photocurrent conditioning circuit according to an embodiment of the invention;

fig. 3 is a schematic diagram of a photocurrent conditioning circuit according to an embodiment of the invention.

Description of reference numerals:

1-a transmitting end; 2-visible optical fiber; 3-a receiving end; 4-photocurrent conditioning circuit; 5-sealing the shell; 6-input bias module; 7-an amplification module; 8-an output bias module; d2-photodiode; r1 — first bias resistor; r2 — second bias resistor; q1-transistor; c1-lead compensation capacitance; c2-decoupling capacitance; VCC-supply voltage; an OUT-signal output terminal; GND-ground.

Detailed Description

Embodiments in accordance with the present invention will now be described in detail with reference to the drawings, wherein like reference numerals refer to the same or similar elements throughout the different views unless otherwise specified. It is to be noted that the embodiments described in the following exemplary embodiments do not represent all embodiments of the present invention. They are merely examples as detailed in the claims and the scope of the present invention is not limited thereto. Features of the various embodiments of the invention may be combined with each other without departing from the scope of the invention.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

The way of conventional photoelectric coupler adopts infrared spectrum and air chamber to the scheme of encapsulating inside realization photoelectric coupler of chip, conventional photoelectric coupler can improve the photoelectric transmission ratio, improves signal transmission's speed and driving force. However, the loss of the infrared spectrum of the conventional photoelectric coupler in the air cavity is very large, if the loss of the infrared spectrum is smaller, the distance of the air cavity is set to be shorter, although the signal can be detected by the photoelectric receiving tube, a variable quantity of voltage jump cannot be detected, and the requirement of triggering a post-stage circuit cannot be met; if the distance between the air cavity and the infrared spectrum is set to be longer in order to enable the withstand voltage of the photoelectric coupler to be higher, the distance between the air cavity and the infrared spectrum cannot be increased without limit and is limited to a certain extent, so that the withstand voltage of the existing photoelectric coupler can only achieve six-seven kilovolts at the highest level at present, the price is expensive, the process is difficult to realize, and the insulating property of the photoelectric coupler cannot be met in isolation application occasions exceeding 10 KV.

Fig. 1 is a schematic structural diagram of an ultrahigh voltage photoelectric coupler according to an embodiment of the present invention, and as shown in fig. 1, the present application discloses an ultrahigh voltage photoelectric coupler, which includes an emitting end 1, a visible optical fiber 2, a receiving end 3, and a photocurrent conditioning circuit 4, where the emitting end 1 is configured to convert an input electrical signal into an optical signal, the visible optical fiber 2 is used as a transmission medium and is configured to transmit the optical signal emitted by the emitting end 1, and one end of the visible optical fiber 2 is connected to the emitting end 1; the receiving end 3 is configured to receive the optical signal transmitted by the visible optical fiber 2, the other end of the visible optical fiber 2 is connected to the receiving end 3, and the photocurrent conditioning circuit 4 is configured to correct the signal received by the receiving end 3.

This application has increased visible fiber 2 and photocurrent conditioning circuit 4 for setting up of conventional optoelectronic coupler newly, because visible fiber 2 has good super high withstand voltage characteristic, keep apart the transmission as the medium of propagation light through setting up visible fiber 2, through the withstand voltage characteristic of adjusting the length of optic fibre in order to control transmitting terminal and receiving terminal 3, follow and pass through the correction of photoelectric current circuit, thereby make receiving terminal 3's receiving effect best, thereby realize that the withstand voltage between transmitting terminal and the receiving terminal 3 of optoelectronic coupler can exceed 10 KV. I.e. the input end and the output end are isolated by the visible fiber 2, and the obtained isolation voltage is at least 10 KV. In addition, the visible optical fiber 2 is a common material, so that the manufacturing cost is low, the material selectivity is strong, the production and debugging are convenient, the visible optical fiber can be bent into any shape, and the manufacturing process is simple. The invention realizes the voltage-withstanding ultrahigh voltage photoelectric coupler of more than 10KV, has good use for occasions such as a low-voltage control high-voltage circuit, high-voltage direct current transmission, high isolation communication, high common mode system communication and the like, and has simple process and improved safety performance.

The visible optical fiber 2 of the present invention is similar to a general optical fiber in principle, and the visible optical fiber 2 is different from the general optical fiber in that: the signal requirement of the visible fiber 2 is more random, and is mainly used for low-speed signals, while the common fiber is a single-mode fiber and a multi-mode fiber, and the light used by the fiber is modulated, and the frequency of the light is very high. The light of the visible light fiber 2 can be adjusted to any frequency, either low or high. The peak velocity of the visible fiber 2 is higher than that of a normal fiber, which is about as small as several hair strands because the visible fiber 2 has a much larger diameter than a normal fiber. In the process, the diameters of the visible optical fiber 2 and the common optical fiber are different, so that a special modern microscope tool is needed for welding the common optical fiber during welding, and the visible optical fiber 2 is simple to install in the process due to the large diameter, so that a special microscope tool is not needed for observing welding. Further, the optical fiber 2 has excellent characteristics such as high insulation resistance, low loss, and elongation, and a photocoupler manufactured by using the same has various characteristics.

For the transmitting end, specifically, the wavelength band of the optical signal output by the transmitting end 1 is a wavelength band corresponding to visible light, and the corresponding wavelength range is 380nm-780 nm. More specifically, the wavelength band of the optical signal output by the emitting end 1 is a red light wavelength band, that is, the emitting end 1 is a red emitting tube, and the corresponding model of the red emitting tube is 1383-2 surf. Due to the wavelength of red light, the conversion efficiency of the red light is high, the transmission distance is long, the loss in the visible optical fiber 2 is the lowest, the emitted light intensity can be ensured to reach the standard, and the obtained signal quality is good. Of course, it is also possible to use light of other wavelength bands, and although the driving current is larger when light of other wavelengths is used, it is only necessary to satisfy the requirement that the emitted light intensity reaches the standard.

For the receiving terminal 3, specifically, the receiving terminal 3 includes a photodiode, and the specific type of the photodiode is: SGPD5051R6, the wave band of the photosensitive diode is matched with the wave band of the optical signal output by the transmitting terminal 1. Because the transmitting terminal 1 converts and outputs light of a certain color, the receiver is sensitive to light of a corresponding color and is insensitive to light of other colors, and by setting the wavelengths of the light of the transmitter and the light of the receiver to be matched, a signal with better received quality can be obtained. For example, when the emitting tube is a red emitting tube, then the receiving tube is a red photodiode, also referred to as a red receiving tube. Since the red light receiving tube is sensitive only to red light and relatively insensitive to other colors, and since the wavelength of red light is long, the loss in the visible optical fiber 2 is the lowest, the intensity of light received by the red light receiving tube is the strongest, and the obtained signal quality is the best.

If the wavelength deviation is small, the wavelength band of the photodiode of the receiving end 3 may not match the wavelength band of the emitting end 1. For example, the wavelength range of red light is 622nm-770nm, the wavelength range of orange is 577nm-597nm, and under the assumption that the manufacturing process is considered to have no deviation, if the emitting end 1 is a red light emitting tube and the receiving end 3 is an orange receiving tube, because the wavelength deviation of the red light emitting tube and the receiving end is between several tens of nm, the performance is not greatly affected by the deviation of several tens of nm, and the performance is greatly affected once the wavelength exceeds 100nm, so the wavelength band of the photodiode of the receiving end 3 is not matched with the wavelength band of the emitting end 1. Of course, there may be a deviation between the emitting end 1 and the receiving end 3 for matching the wavelengths of the light, and the deviation is caused by the manufacturing process of the devices of the emitting end 1 and the receiving end 3, and generally the deviation is several nm, so the influence on the signal is not great.

For the photocurrent conditioning circuit 4, the photocurrent conditioning circuit 4 corrects the signal received by the receiving terminal 3. The photocurrent conditioning circuit 4 uses the reverse characteristic of the photodiode, when the photodiode receives an optical signal, the reverse leakage current of the photodiode increases, the leakage current and the intensity of the light change linearly, the leakage current increases along with the increase of the intensity of the light, the conditioning circuit applies a reverse bias voltage to the photodiode, so that the leakage current is generated, and then the leakage current is converted into a voltage and amplified. Specifically, fig. 2 is a schematic structural diagram of a photocurrent conditioning circuit according to an embodiment of the present invention, and as shown in fig. 2, the photocurrent conditioning circuit 4 includes an input bias module 6, an amplification module 7, and an output bias module 8, where the input bias module 6 is configured to generate a leakage current, the amplification module 7 is configured to amplify the leakage current generated by the input bias module 6, and the output bias module 8 is configured to convert the leakage current into a voltage signal to output a digital signal. The signal received by the photodiode is corrected by arranging an input bias module 6, an amplification module 7 and an output bias module 8, so that the output signal is a stable signal.

More specifically, fig. 3 is a schematic diagram of a photocurrent conditioning circuit according to an embodiment of the invention, as shown in fig. 3, wherein D2 is a photodiode, R1 is a first bias resistor, R2 is a second bias resistor, Q1 is a transistor, C1 is a lead compensation capacitor, C2 is a decoupling capacitor, VCC represents a power supply voltage, OUT represents a signal output terminal, and GND represents a ground terminal. The input bias module 6 comprises a first bias resistor R1, one end of the first bias resistor R1 is connected to the anode of the photodiode D2, and the other end of the first bias resistor R1 is grounded. The amplifying module 7 comprises a transistor Q1, the base of the transistor Q1 is connected with one end of the first bias resistor R1, the base of the transistor Q1 is connected with the anode of the photodiode D2, and the emitter of the transistor Q1 is grounded. The output bias module 8 comprises a second bias resistor R2, one end of the second bias resistor R2 is connected to the cathode of the photodiode D2, and the other end of the second bias resistor R2 is connected to the collector of the photodiode D2. The cathode of the led is connected to a supply voltage, the first bias resistor R1 is used to provide a definite zero state input for the transistor Q1 when no photocurrent is supplied, and the second bias resistor R2 is used to provide a high voltage bias for the output of the transistor Q1. The first bias resistor R1 and the second bias resistor R2 are respectively arranged for different situations of no light and light, the bias resistors are arranged for the input of no light current to prevent the output from vibrating, the bias resistors are provided for the light current to provide a bias voltage, the current is converted into voltage, and finally, a digital signal is output.

In order to improve the data transmission rate, a lead compensation capacitor C1 is provided, the photo-conditioning circuit 4 includes a lead compensation capacitor C1 for leading the phase of the collector of the transistor Q1, one end of the lead compensation capacitor C1 is connected to the cathode of the photodiode D2, the other end is connected to the collector of the transistor Q1, and the collector of the transistor is also the signal output terminal OUT. By providing the lead compensation capacitor C1, the data rate can be increased by advancing its phase for collector variation.

In addition, for anti-interference, the photoelectric conditioning circuit further comprises a decoupling capacitor C2 for reducing interference of fluctuation of a power supply voltage on the leakage current, wherein one end of the decoupling capacitor C2 is connected with the power supply voltage, and the other end is grounded. By providing a decoupling capacitor C2, it is possible to prevent a variation in leakage current caused by fluctuations in the power supply voltage, and since the transistor Q1 is a high-frequency transistor, the amplification factor is large, and generally, the amplification factor ranges from 60 to 200 times, and even if a small leakage current is generated by a small fluctuation, the amplification by the transistor becomes large, and therefore, by providing a decoupling capacitor, it is possible to reduce interference.

The length of the visible optical fiber 2 is generally set to be 8mm-24mm, generally, the visible optical fiber 2 is set at intervals of 10KV/mm, 10kV withstand voltage is provided for each mm of the optical fiber, but 8-10 times of margin is generally reserved in design, namely 8-10mm, the electrical property is better when the visible optical fiber is increased, the size of a device is increased, the visible light transmission loss is positively correlated with the distance, the signal delay of a receiving part is increased, for a 10kV optical coupler, generally 8-12mm can be taken, and the optimal 10mm is taken. And the length of the visible optical fibers 2 arranged at intervals is 10KV/mm, the installation process is simple, the structural deformation is small, and the consistency of devices is improved. 10 mm's length can adapt to manual assembly, also can adapt to the machine assembly, and length is short, has stronger meeting an emergency, and non-deformable makes transmitting terminal 1 and receiving terminal 3 can keep good contact, and the position is difficult for squinting during the embedment, and the uniformity improves. Similarly, for the photocoupler having withstand voltage of 20KV, the length of the visible light fiber 2 may be set to 16 to 24mm, and 20mm is preferably selected.

More specifically, the visible light fiber 2 is made of teflon, and the teflon material is used as the material of the visible light fiber 2, so that the leakage current can be minimized, and the loss of light passing through the visible light fiber 2 can be minimized.

The withstand voltage of the photoelectric coupler is realized on 10KV, the withstand voltage tester is used for testing the input end and the output end to obtain that the voltage difference which can be borne between the input end and the output end is more than 10KV, the data transmission rate can reach 1Mbps, 1M data is input into the input end, the data is measured by an oscilloscope through the output end to determine whether the data can be transmitted, and through experimental verification, the data can be transmitted when the input data is 1 Mbps.

Superhigh pressure photoelectric coupler still includes sealed shell 5, sealed shell 5 will emission end 11, visible light fiber 2, receiving terminal 3 and photocurrent conditioning circuit 4 carry out insulating filling and seal, specifically, insulating filling material includes polyethylene, polytetrafluoroethylene, FEP etc. can guarantee on the one hand like this that the leakage current is leakless, and on the other hand has guaranteed tension for tension is fit for, does not influence sealed part. The prior packaging is plastic packaging, and the internal devices are made by mould casting, but the prior packaging is not suitable for making high-voltage devices.

As another embodiment of the present invention, a digital signal system is disclosed, which includes the above-described ultrahigh-voltage photocoupler.

This application has increased visible fiber 2 and photocurrent conditioning circuit 4 for setting up of conventional optoelectronic coupler newly, because visible fiber 2 has good super high withstand voltage characteristic, keep apart the transmission as the medium of propagation light through setting up visible fiber 2, through the withstand voltage characteristic of adjusting the length of optic fibre in order to control transmitting terminal 1 and receiving terminal 3, follow and pass through the correction of photoelectric current circuit, thereby make receiving terminal 3's receiving effect best, thereby realize that the withstand voltage between transmitting terminal and the receiving terminal 3 of optoelectronic coupler can exceed 10 KV. I.e. the input end and the output end are isolated by the visible fiber 2, and the obtained isolation voltage is at least 10 KV. In addition, the visible optical fiber 2 is a common material, so that the manufacturing cost is low, the material selectivity is strong, the production and debugging are convenient, the visible optical fiber can be bent into any shape, and the manufacturing process is simple. The invention realizes the voltage-withstanding ultrahigh voltage photoelectric coupler of more than 10KV, has good use for occasions such as a low-voltage control high-voltage circuit, high-voltage direct current transmission, high isolation communication, high common mode system communication and the like, and has simple process and improved safety performance.

Although the present disclosure has been described above, the scope of the present disclosure is not limited thereto. Various changes and modifications may be effected therein by one of ordinary skill in the pertinent art without departing from the spirit and scope of the present disclosure, and these changes and modifications are intended to be within the scope of the present disclosure.