Lightning surge protection circuit and data acquisition circuit comprising same
By designing lightning surge protection circuits in the data acquisition circuit, using discharge tubes, varistors, bidirectional TVS tubes and optocouplers, the protection problem of lightning surges and interference in the data acquisition circuit is solved, and the circuit stability is achieved Improvement of sexual and anti-interference ability.
Patent Information
- Application Number
- CN202323476666.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-20
- Publication Date
- 2025-01-10
- Estimated Expiration
- 2033-12-20
AI Technical Summary
The existing data acquisition circuit lacks the hardware lightning-proof surge function, has poor anti-interference ability, is prone to false alarms, and has no anti-reverse connection function, resulting in circuit damage.
A lightning surge circuit is designed, including discharge tubes, varistors, bidirectional TVS tubes, optocouplers and diodes. Through the combination of these components, the protection and interference filtering of lightning surge voltage is achieved, and the data is The MCU module and LoRa module are introduced into the acquisition circuit, combining hardware and software anti-shake filtering functions.
Effectively protect the circuit from lightning surges, enhance anti-interference ability, prevent false alarms and reverse connection damage, ensure stable operation of the circuit, and improve the reliability and stability of the data acquisition circuit.
Smart Images
Figure CN222339035U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of lightning surge protection, in particular to a lightning surge protection circuit and a data acquisition circuit comprising the circuit. Background Art
[0002] With the continuous advancement of science and technology and the increasing development of power systems, the operation and management of substations play a vital role in the stability and safety of power systems. Among them, substation data acquisition circuits play an important role in ensuring the safe and stable operation of substations and power grids.
[0003] The current data acquisition circuit has the following problems:
[0004] 1. The remote signal input interface has no hardware lightning surge protection function, and the circuit is easily damaged;
[0005] 2. The remote signal input interface has poor anti-interference ability and is prone to false alarms;
[0006] 3. The remote signal input interface has no anti-reverse connection function, and the optocoupler is easily damaged after reverse connection. Utility Model Content
[0007] The utility model aims to provide a lightning surge protection circuit and a data acquisition circuit including the circuit in order to better protect the circuit after the lightning surge voltage surges.
[0008] The purpose of the utility model can be achieved through the following technical solutions:
[0009] A lightning surge protection circuit comprises a discharge tube VD1, two ends of the discharge tube VD1 are connected to an input positive electrode DI1 and an input negative electrode GND-IO-O of the lightning surge protection circuit, two ends of the discharge tube VD1 are connected in parallel to a varistor RV1, the input negative electrode GND-IO-O is connected to one end of a varistor RV2, the other end of the varistor RV2 is grounded, one end of the varistor RV1 connected to the input positive electrode DI1 is connected to one end of a bidirectional TVS tube V1, the other end of the bidirectional TVS tube V1 is connected to one end of a resistor R1, the other end of the resistor R1 is connected to an optical coupler T1, one end of the varistor RV1 connected to the input negative electrode GND-IO-O is connected to the cathode of a diode D1, the anode of the diode D1 is connected to the optical coupler T1, and the optical coupler T1 is connected to an output end DIO1 of the lightning surge protection circuit.
[0010] Furthermore, the other end of the resistor R1 is connected to the positive terminal of the diode of the optocoupler T1 , and the anode of the diode D1 is connected to the negative terminal of the diode of the optocoupler T1 .
[0011] Furthermore, a resistor R2 is connected in parallel between the anode terminal of the diode of the optocoupler T1 and the cathode terminal of the diode of the optocoupler T1 .
[0012] Furthermore, a capacitor C1 is connected in parallel between the positive terminal of the diode of the optical coupler T1 and the negative terminal of the diode of the optical coupler T1.
[0013] Furthermore, the collector terminal of the optocoupler T1 is connected to a positive voltage.
[0014] Furthermore, the positive voltage connected to the collector terminal of the optocoupler T1 is 3.3V.
[0015] Furthermore, the emitter terminal of the optical coupler T1 is connected to one end of the resistor R3 , and the other end of the resistor R3 is connected to the output terminal DIO1 of the lightning surge protection circuit.
[0016] Furthermore, the output terminal DIO1 of the lightning surge protection circuit is connected to one end of the capacitor C2, the other end of the capacitor C2 is grounded, the emitter end of the optical coupler T1 is connected to one end of the resistor R4, the other end of the resistor R4 is grounded.
[0017] On the other hand, the utility model further provides a data acquisition circuit including the above-mentioned lightning surge protection circuit, the data acquisition circuit includes an MCU module and a remote control and remote signaling module, the remote control and remote signaling module includes a lightning surge protection circuit, the input positive electrode DI1 and the input negative electrode GND-IO-O of the lightning surge protection circuit are respectively the remote signaling input positive electrode and the remote signaling input negative electrode of the remote control and remote signaling module, and the output terminal DIO1 of the lightning surge protection circuit is the remote signaling output of the remote control and remote signaling module;
[0018] The MCU module is also connected to the LoRa module, and each communication interface of the MCU module is connected to the encryption module.
[0019] Furthermore, the MCU module is an LPC1766 chip, the model of the LoRa module is Ra-01SC, and the chip model of the encryption module is SC1161.
[0020] Compared with the prior art, the utility model has the following beneficial effects:
[0021] (1) The utility model arranges a varistor RV2, a varistor RV1 and a discharge tube VD1 between the positive and negative electrodes of the input terminal of the remote signal and the ground. When the lightning surge voltage at the input terminal flows into the positive and negative electrodes of the input terminal of the remote signal and the ground, the varistor RV1 or the discharge tube VD1 is turned on, and the varistor RV2 is turned on, and the high voltage is released to protect the subsequent circuit from being affected.
[0022] (2) The utility model sets a bidirectional TVS tube V1. When the input voltage of the DI1 terminal is less than a certain value, the circuit does not work, which can remove the interference of the inductive electricity and filter out the jitter false alarm. The utility model also sets a diode D1 to prevent the positive and negative poles of the remote signal input terminal from being reversely connected, causing the optical coupler to be damaged by reverse voltage. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 This is the lightning surge protection circuit diagram of the utility model;
[0024] Figure 2 This is a data acquisition circuit diagram of the utility model. DETAILED DESCRIPTION
[0025] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and a specific operation process, but the protection scope of the present invention is not limited to the following embodiments.
[0026] The utility model provides a lightning surge protection circuit and a data acquisition circuit including the circuit. Figure 1 As shown, the circuit diagram of the data acquisition circuit is as follows Figure 2 shown.
[0027] The lightning protection surge circuit includes a discharge tube VD1, two ends of the discharge tube VD1 are connected to the input positive electrode DI1 and the input negative electrode GND-IO-O of the lightning protection surge circuit, two ends of the discharge tube VD1 are connected in parallel with a varistor RV1, the input negative electrode GND-IO-O is connected to one end of the varistor RV2, the other end of the varistor RV2 is grounded, one end of the varistor RV1 connected to the input positive electrode DI1 is connected to one end of the bidirectional TVS tube V1, the other end of the bidirectional TVS tube V1 is connected to one end of the resistor R1, the other end of the resistor R1 is connected to the optocoupler T1, one end of the varistor RV1 connected to the input negative electrode GND-IO-O is connected to the cathode of the diode D1, the anode of the diode D1 is connected to the optocoupler T1, and the optocoupler T1 is connected to the output end DIO1 of the lightning protection surge circuit.
[0028] The other end of the resistor R1 is connected to the positive terminal of the diode of the optocoupler T1, and the anode of the diode D1 is connected to the negative terminal of the diode of the optocoupler T1.
[0029] A resistor R2 is connected in parallel between the positive terminal of the diode of the optocoupler T1 and the negative terminal of the diode of the optocoupler T1. A capacitor C1 is connected in parallel between the positive terminal of the diode of the optocoupler T1 and the negative terminal of the diode of the optocoupler T1. The collector terminal of the optocoupler T1 is connected to a positive voltage. The positive voltage connected to the collector terminal of the optocoupler T1 is 3.3V. The emitter terminal of the optocoupler T1 is connected to one end of the resistor R3, and the other end of the resistor R3 is connected to the output terminal DIO1 of the lightning protection surge circuit. The output terminal DIO1 of the lightning protection surge circuit is connected to one end of the capacitor C2, and the other end of the capacitor C2 is grounded. The emitter terminal of the optocoupler T1 is connected to one end of the resistor R4, and the other end of the resistor R4 is grounded.
[0030] The utility model also proposes a data acquisition circuit including the above-mentioned lightning surge protection circuit, the data acquisition circuit includes an MCU module and a remote control and remote signaling module, the remote control and remote signaling module includes a lightning surge protection circuit, the input positive electrode DI1 and the input negative electrode GND-IO-O of the lightning surge protection circuit are respectively the remote signaling input positive electrode and the remote signaling input negative electrode of the remote control and remote signaling module, and the output terminal DIO1 of the lightning surge protection circuit is the remote signaling output of the remote control and remote signaling module;
[0031] The MCU module is also connected to the LoRa module, and each communication interface of the MCU module is connected to the encryption module.
[0032] The MCU module is the LPC1766 chip, the LoRa module model is Ra-01SC, and the encryption module chip model is SC1161.
[0033] The remote signal input voltage is generally DC24V, DI1 is the positive pole of the remote signal input, and GND-IO-O is the negative pole of the remote signal input. EGND is connected to the housing and connected to the ground terminal. The varistor RV1 and the discharge tube VD1 are connected between DI1 and GND-IO-O. The varistor RV2 is connected between GND-IO-O and EGND. The bidirectional TVS tube V1 and the resistor R1 are connected in series between the varistor RV1 and the optocoupler pin 1. The resistor R2 and the capacitor C1 are connected in parallel between the optocoupler pins 1 and 2. The diode D1 is connected in series between the varistor RV1 and the resistor R2. The optocoupler pin 4 is connected to the power supply 3.3V. The resistor R4 is connected in series between the optocoupler pin 3 and the ground. The resistor R3 is connected in series between the optocoupler pin 3 and the detection terminal DIO1. The capacitor C2 is connected in series between the detection terminal DIO1 and the power ground.
[0034] When the external switch quantity is separated, the front-end circuit of the optocoupler does not work, the back-end of the optocoupler does not conduct, and the detection terminal DIO1 is pulled down to GND through the resistor R4, that is, the detection terminal DIO1 is low level; when the external switch quantity is closed, there is a DC24V input at the positive input terminal of the remote signal, the bidirectional TVS tube V1 works in the breakdown state, the circuit works normally, the optocoupler emits light to turn on the back end of the optocoupler, and the detection terminal DIO1 is high level. When the lightning surge voltage is applied between the remote signal input DI1 and GND-IO-O, the varistor RV1 or the discharge tube VD1 is turned on (the varistor and the discharge tube provide double protection), and the high voltage is released to protect the subsequent circuit from being affected; when the lightning surge voltage is applied between the remote signal input DI1, GND-IO-O and EGND (earth), the varistor RV1 or the discharge tube VD1 is turned on, and the varistor RV2 is turned on, and the high voltage is released to protect the subsequent circuit from being affected. The function of the bidirectional TVS tube V1 in the circuit is that when the input voltage of the DI1 terminal is less than 5V, the circuit will not work, which can remove the interference of inductive electricity. The function of the diode D1 in the circuit is to prevent the positive and negative poles of the remote signal input terminal from being reversed, causing the optocoupler to withstand reverse voltage and be damaged (generally, the reverse voltage of the optocoupler is 6V). The resistor R1 not only plays a current limiting role, but also forms an RC low-pass filter with the capacitor C1. By selecting appropriate resistance and capacitance values, pulse interference above 1KHz can be filtered out. The resistor R2 pulls down the optocoupler 1 foot to prevent the optocoupler 1 foot from being suspended and affected by external interference when there is no remote signal input. The resistors R3 and C2 at the rear end of the optocoupler also play the role of a low-pass filter, further filtering out pulse interference above 1KHz. The resistor R4 pulls down to provide a default low-level signal for the detection terminal DIO1. The filtering frequency of the low-pass filter can be adjusted by adjusting the values of the devices R1, C1, R3, and C2.
[0035] The utility model device has a remote signal input interface that can withstand a 2KV voltage impact of a lightning surge between the positive and negative poles, and a 4KV voltage impact of a lightning surge between the positive and negative poles and the earth without being damaged, thereby ensuring the normal function of the interface; the utility model remote signal input interface can filter out pulse interference above 1KHz and filter out jitter false alarms; the utility model remote signal input interface has a hardware positive and negative pole anti-reverse connection function to avoid damage to the hardware due to wiring errors.
[0036] The data acquisition circuit includes power module, MCU core module, encryption module, communication module, LCD display button module, remote control module, LoRa module, etc. The MCU core module includes multiple communication interfaces, and each communication interface has encryption and decryption functions, responsible for data processing, storage, intelligent control, etc.
[0037] When the data acquisition circuit communicates, a dedicated encryption chip can be used to encrypt and decrypt the data, and it can be connected to a security platform. The communication module includes 4G, network port, RS485, RS232, etc. Each communication interface can be flexibly configured with various communication protocols to meet the actual needs of on-site applications. The LCD display button module can query and set various parameters through the human-machine interface, avoiding the disadvantage of only relying on PC operation.
[0038] The functions of the remote control and telesignaling module include telesignaling input, which has hardware anti-shake filtering function and software anti-shake filtering function, and the software anti-shake filtering time can be flexibly set; telesignaling output, which has a physical preset relay, and the remote control output pulse bandwidth can be set through software or hardware circuit.
[0039] The wireless LoRa module has both access point and aggregation node functions, and can support communications in the 470-510MHz and 2400-2483.5MHz frequency bands at the same time, taking into account the access of low-power LoRa and micro-power LoRa, making it fully compatible with data communications of various wireless LoRa sensors.
[0040] The device of the utility model has all the functions of the substation data acquisition device and the wireless LoRa access capability, and the wireless LoRa can work in both the access node mode and the aggregation node mode, combining the two devices into one, greatly reducing the on-site failure rate and construction complexity, improving the operating stability of the equipment, and improving the reliability of the power grid; the intelligent control of the utility model can realize automatic control of fans, water pumps, air conditioners, dehumidifiers, lights and other equipment according to preset thresholds combined with environmental data, and realize over-value alarms, fault alarms, etc., to assist repair personnel in finding solutions, troubleshooting, and improving the reliability of the power grid.
[0041] When the data acquisition circuit is working, the LoRa module receives the substation data from multiple LoRa sensors, such as the temperature information of the substation. The LoRa module transmits the information to the MCU core module. The MCU core module receives the status voltage of each device from the remote signal input through the remote signal part of the remote signal remote control module, and outputs high and low levels at the remote signal output end through the lightning surge protection circuit. The temperature information obtained by the MCU core module is compared with the threshold through the comparator. If the threshold is exceeded and the remote signal output end outputs a high level, the device fails, the MCU core module alarms, and outputs a low level to the remote control part of the remote signal remote control module. The remote control part sends the low level to the faulty device, and the faulty device stops working after receiving the low level. In the above process, the communication between modules can be realized through the interface of the communication module, and the information sent during mutual communication can be encrypted through the encryption module. Or when the MCU core module transmits data, encryption and decryption are directly performed through the communication interface of the MCU core module.
[0042] The preferred specific embodiments of the utility model are described in detail above. It should be understood that ordinary technicians in this field can make many modifications and changes based on the concept of the utility model without creative work. Therefore, all technical solutions that can be obtained by technicians in this technical field based on the concept of the utility model through logical analysis, reasoning or limited experiments on the basis of the existing technology should be within the scope of protection determined by the claims.
Claims
1. A lightning surge protection circuit, characterized in that: The circuit includes a discharge tube VD1, two ends of the discharge tube VD1 are connected to the input positive electrode DI1 of the lightning protection surge circuit and the input negative electrode GND-IO-O of the lightning protection surge circuit, two ends of the discharge tube VD1 are connected in parallel with a varistor RV1, the input negative electrode GND-IO-O is connected to one end of the varistor RV2, the other end of the varistor RV2 is grounded, one end of the varistor RV1 connected to the input positive electrode DI1 is connected to one end of the bidirectional TVS tube V1, the other end of the bidirectional TVS tube V1 is connected to one end of the resistor R1, the other end of the resistor R1 is connected to the optocoupler T1, one end of the varistor RV1 connected to the input negative electrode GND-IO-O is connected to the cathode of the diode D1, the anode of the diode D1 is connected to the optocoupler T1, and the optocoupler T1 is connected to the output end DIO1 of the lightning protection surge circuit.
2. A lightning surge protection circuit according to claim 1, characterized in that: The other end of the resistor R1 is connected to the positive terminal of the diode of the optocoupler T1, and the anode of the diode D1 is connected to the negative terminal of the diode of the optocoupler T1.
3. A lightning surge protection circuit according to claim 2, characterized in that: A resistor R2 is connected in parallel between the positive terminal of the diode of the optocoupler T1 and the negative terminal of the diode of the optocoupler T1.
4. A lightning surge protection circuit according to claim 2, characterized in that: A capacitor C1 is connected in parallel between the positive terminal of the diode of the optocoupler T1 and the negative terminal of the diode of the optocoupler T1.
5. The lightning surge protection circuit according to claim 1, characterized in that: The collector terminal of the optocoupler T1 is connected to a positive voltage.
6. A lightning surge protection circuit according to claim 5, characterized in that: The collector terminal of optocoupler T1 is connected to a positive voltage of 3.3V.
7. The lightning surge protection circuit according to claim 5, characterized in that: The emitter end of the optical coupler T1 is connected to one end of the resistor R3, and the other end of the resistor R3 is connected to the output end DIO1 of the lightning protection surge circuit.
8. The lightning surge protection circuit according to claim 7, characterized in that: The output terminal DIO1 of the lightning surge protection circuit is connected to one end of the capacitor C2, the other end of the capacitor C2 is grounded, the emitter end of the optical coupler T1 is connected to one end of the resistor R4, and the other end of the resistor R4 is grounded.
9. A data acquisition circuit comprising any lightning surge protection circuit according to claim 1 to claim 8, characterized in that: The data acquisition circuit includes an MCU module and a remote control and remote signaling module. The remote control and remote signaling module includes a lightning surge protection circuit. The input positive electrode DI1 and the input negative electrode GND-IO-O of the lightning surge protection circuit are respectively the remote signaling input positive electrode and the remote signaling input negative electrode of the remote control and remote signaling module. The output terminal DIO1 of the lightning surge protection circuit is the remote signaling output of the remote control and remote signaling module. The MCU module is also connected to the LoRa module, and each communication interface of the MCU module is connected to the encryption module.
10. The lightning surge protection circuit according to claim 9, characterized in that: The MCU module is the LPC1766 chip, the LoRa module model is Ra-01SC, and the encryption module chip model is SC1161.