CN210923930U

CN210923930U - SPD leakage current online intelligent monitoring device

Info

Publication number: CN210923930U
Application number: CN201921686138.6U
Authority: CN
Inventors: 任莎
Original assignee: CHANGSHA RUNXUN COMMUNICATION EQUIPMENT CO LTD
Current assignee: CHANGSHA RUNXUN COMMUNICATION EQUIPMENT CO LTD
Priority date: 2019-10-10
Filing date: 2019-10-10
Publication date: 2020-07-03
Anticipated expiration: 2029-10-10

Abstract

The utility model discloses an SPD leakage current on-line intelligent monitoring device, which can calculate the resistive leakage current of SPD under the working voltage through the setting of a micro-current transmitter, a voltage transmitter, an acquisition module, an MCU module and a resistive current calculation module; through the arrangement of the counting module and the precision calibration module of the micro-current transmitter, the magnetization phenomenon of the micro-current transmitter when the SPD module is in through-flow to the ground can be eliminated, the precision of leakage current detection is ensured, and the number of through-flow to the ground and the lightning stroke time of the SPD module can be monitored. The utility model discloses can be fast and accurately reachd the degradation degree and the operating condition of SPD, do benefit to the user and in time change the maintenance to the SPD module of degradation and handle, prevent to strike because of thunderbolt or surge and cause the SPD that the hindering nature of SPD module leaks the current increase and leads to generate heat, the burning or because of the secondary accident such as thunderbolt when heat-sensitive dropout protection is lacked takes place.

Description

SPD leakage current online intelligent monitoring device

Technical Field

The utility model belongs to SPD (Surge protection Device) field especially relates to an SPD leaks current online intelligent monitoring Device.

Background

Along with the use of low-voltage line lightning protection devices (SPDs) made of zinc oxide varistors (MOVs)) in industries such as building electrical, railway, highway, telecommunication, electric power and petrochemical industries in a large quantity. Experience has shown that: the initial leakage current of the piezoresistor when leaving the factory is closely related to the service life characteristic and the safety of the piezoresistor, the piezoresistor generates heat when the leakage current flows through the piezoresistor, the voltage-sensitive voltage is reduced and the leakage current is further increased when the heat is generated, and finally the piezoresistor is ignited and burnt due to overhigh temperature in such a circulating way, so that great potential safety hazards are caused. Therefore, accidents caused by deterioration and failure of the SPD (failure accident of lightning protection after failure, too large leakage current of the SPD itself, and fire accidents caused by high temperature) are increasing. These accidents are mostly due to SPD leakage currents.

The SPD leakage current qualification judgment data established by the national lightning protection device detection standard at present is mainly a method for manually and periodically adopting a corresponding instrument to perform off-line detection. According to the characteristics of large quantity of SPDs, point position dispersion and the like of the existing detection method, the consumption of manpower and material resources is large, the deterioration progress of the SPDs cannot be tracked anytime and anywhere, and meanwhile, the detection precision is influenced by the magnetization phenomenon caused by passing of lightning current to detection equipment. In addition, the currently used detection instrument adopts a voltage dependent resistor (UN) which is 0.75 times that of the SPD, the number of the SPDs is large, the installation is scattered, the detection work is greatly subjected to manpower and material resource expenses, and the defects of the currently used detection instrument are that the time, the frequency, the precision and the economic limitations are limited. Therefore, the method can detect the resistive current (namely the leakage current) flowing through the valve plate on line under the nominal continuous working voltage, can track the parameter change of the lightning protection module (SPD) in real time to provide data basis, discover and eliminate unqualified SPDs in advance, and improve the safety and reliability of the lightning protection module (SPD).

SUMMERY OF THE UTILITY MODEL

To above technical problem, the utility model discloses a system of at line pair SPD leakage current monitoring under nominal operating voltage, zinc oxide (MOV) leakage current in its detection lightning protection device (SPD) that can be real-time accurate, report an emergency and ask for help or increased vigilance (deterioration of early warning lightning protection device in advance, inefficacy) when to SPD leakage current bigger than normal, report an emergency and ask for help or increased vigilance in real time to the module of degradation, inefficacy, the suggestion user in time changes corresponding lightning protection module, can avoid lightning protection inefficacy and secondary calamity to produce effectively.

The system comprises a micro-current transmitter, a voltage transmitter, an acquisition module, an MCU module, a resistive current calculation module, a counting module and a micro-current transmitter precision calibration module, wherein the micro-current transmitter is connected with the input end of the acquisition module through a relay normally-closed end, the output end of the acquisition module is connected with the input end of the resistive current calculation module, the output end of the resistive current calculation module is connected with the MCU module, the counting module is connected between the relay normally-closed end and the acquisition module, the micro-current transmitter precision calibration module is connected between the relay normally-open end and the MCU module, when SPD has no lightning current impact, a current signal detected by the micro-current transmitter and a voltage signal detected by the voltage transmitter are simultaneously input into the acquisition module, the acquisition module outputs a composite current value, a voltage value and a phase angle α to the resistive current calculation module, the resistive current is calculated by the resistive current calculation module and output to the MCU module through a current value and a phase angle α, when the SPD has no lightning current impact, the counting module counts, the MCU module stores the number of lightning current and the lightning stroke time of the micro-current transmitter, the sensitivity of the micro-current transmitter is magnetized, the micro-current transmitter is switched to the MCU module, and the micro-current transmitter is switched to the micro-current transmitter to the micro-.

Further, the resistive current calculation module has a calculation formula as follows: i is_RI × cos α wherein I_RIs resistive current, I is the composite current detected by the micro-current transducer, and α is the phase angle.

Furthermore, the SPD leakage current on-line intelligent monitoring device further comprises a remote monitoring module and a communication module, wherein the MCU module is connected with the remote monitoring module through the communication module and sends out MCU data, and the SPD on-line intelligent monitoring device is communicated with the remote monitoring module.

Further, the SPD leakage current online intelligent monitoring device further comprises a display module used for displaying the deterioration degree of the SPD according to the analysis processing result of the MCU module, and the input end of the display module is connected with the output end of the MCU module.

Furthermore, the SPD leakage current online intelligent monitoring device further comprises a power supply module used for providing corresponding power supply signals for the MCU module and the display module, and the output end of the power supply module is connected with the power supply ends of the MCU module and the display module.

The utility model has the advantages that the leakage current of the SPD can be calculated by setting the micro-current transmitter, the voltage transmitter, the acquisition module, the MCU module and the resistive current calculation module; through the arrangement of the counting module and the precision calibration module of the micro-current transmitter, the magnetization phenomenon of lightning current on the micro-current transmitter can be eliminated, the precision of detecting the leakage current of the SPD is ensured, and the number of times of passing the large current of the SPD module and the lightning stroke time can be monitored; meanwhile, the monitoring device is an online monitoring product, can monitor leakage current (resistive current), failure and the states of a protection switch of SPDs of different interface types of all different manufacturers, alarms the SPD module with larger leakage current in advance, alarms the deteriorated and failed SPD modules in real time, realizes the replacement of unqualified SPD modules in advance, avoids accidents caused by deterioration and failure of SPDs (secondary lightning stroke accidents due to failure lightning protection loss, fire accidents caused by excessive leakage current of SPDs and heating), greatly reduces manpower and material resources, tracks the deterioration progress of SPDs anytime and anywhere, accurately eliminates the SPD modules which are not operated under the nominal working voltage, and has important significance in both social benefit and economic benefit.

Drawings

Fig. 1 is a block diagram of the flow of the present invention.

In the drawings: 1. the device comprises an acquisition module, 11 a micro-current transmitter, 12 a voltage transmitter, 13 a relay, 2 a resistive current calculation module, 3 an MCU module, 4 a communication module, 5 a remote monitoring module, 6 a counting module, 7 a micro-current transmitter precision calibration module, 8 a power supply module, 9 and a display module.

Detailed Description

The present invention will be described in further detail with reference to the following examples and drawings, but the present invention is not limited thereto.

As shown in fig. 1, an SPD leakage current online intelligent monitoring device includes a micro-current transmitter 11, a voltage transmitter 12, an acquisition module 1, a resistive current calculation module 2 and an MCU module 3, the micro-current transmitter 11 is connected with the acquisition module 1 through a relay 13, the acquisition module 1 is connected to a normally closed end of the relay 13, the acquisition module 1 includes an AD conversion unit and a phase angle detection, when no lightning current is in normal operation in the SPD, a current analog signal and a voltage analog signal acquired by the micro-current transmitter 11 and the voltage transmitter 12 are simultaneously output to the acquisition module 1, a phase angle α between voltage and current is obtained after the phase angle detection, and a composite current value is obtained after the AD conversion unit, and the composite current value is a composite current I detected by the micro-current transmitter 11, that is, a resistive current I_RAnd a capacitive current I_CThe capacitive current I is removed through the resistive current calculation module 2_CThen the resistance current I of each phase module of SPD flowing through the valve plate under the nominal continuous working voltage can be obtained_R(i.e. leakage current) and output it to the MCU block 3, where the resistive current calculation formula is: i is_RWhen no leakage current exists in the circuit or the leakage current is small, namely α approaches 90 degrees, the leakage current in the circuit becomes large when α is gradually reduced and exceeds a limit value, an alarm is given, and the circuit is replaced in advance.

As shown in fig. 1, an SPD leakage current online intelligent monitoring device further includes a counting module 6 and a micro-current transducer precision calibration module 7, the counting module 6 is connected between a normally closed end of a relay 13 and an MCU module 3 through a comparison circuit, the micro-current transducer precision calibration module 7 is connected between a normally open end of the relay 13 and the MCU module 3, when normal, no lightning current passes through, the current in the circuit is less than 1mA and much less than the current conducted by the comparison circuit, at this time, the counting module 6 does not work, the resistive current can be calculated through the current signal detected by the micro-current transducer 11 and the voltage signal detected by the voltage transducer 12, when the SPD is impacted by the lightning current, the voltage exceeds the voltage-dependent voltage UN (UN is 1mA), the SPD module instantly becomes a low-resistance state, the lightning current flows to the ground, because the lightning current is much greater than 1mA, the comparison circuit is conducted at this time, counting module 6 counts, and number of times and the time of lightning current are stored to MCU module 3, and little current transmitter 11 has been magnetized by lightning current this moment, and sensitivity distortion, at this moment MCU module 3 control relay 13 switch to the end of starting normally, triggers little current transmitter precision calibration module 7 work, and little current transmitter precision calibration module 7 receives the first signal that MCU module 3 sent and begins work this moment, and first signal process little current transmitter precision calibration module 7's signal amplification and power amplification back, output second signal passes through relay 13 and gives little current transmitter 11 for eliminate little current transmitter 11 and strike the phenomenon of magnetization under the lightning current, ensure the accuracy of monitoring data, prevent the production of wrong report police phenomenon. When the micro-current transmitter 11 recovers the initial sensitivity, the MCU module 3 controls the relay 13 to switch to the normally closed end.

The voltage transmitter 12 comprises a plurality of input ends and a plurality of output ends, the input ends of the voltage transmitter 12 are respectively connected with corresponding live wires, and the output end of the voltage transmitter 12 is connected with the input end of the AD conversion unit. Voltage transmitter 12 is used for gathering the voltage on each looks live wire, and after the voltage reduction according to certain proportion, become 0-5V's voltage signal, transmit to AD converting unit, transmit to MCU module 3 after the resistive current computing module 2 after converting into digital signal, MCU module 3 carries out analysis processes, if the SPD who is connected with a certain live wire of the same way damages or the trouble, then the voltage of this way will not be in normal standard range, the digital signal who transmits to MCU module 3 this moment will also be unusual, through the collection and the analysis back of each looks live wire voltage signal, can know the specific position of trouble fast, convenience of customers in time maintains the change.

The SPD leakage current on-line intelligent monitoring device further comprises a remote monitoring module 5 and a communication module 4, wherein the communication module 4 is connected between the MCU module 3 and the remote monitoring module 5 and is used for realizing communication between the MCU module 3 and the remote monitoring module 5. Specifically, the communication module 3 can adopt an RS485 or a wireless module to realize communication.

The SPD leakage current on-line intelligent monitoring device further comprises a display module 9 for displaying the deterioration degree of the SPD according to the analysis and processing result of the MCU module 3, and the input end of the display module 9 is connected with the output end of the MCU module 3. In order to visually display the deterioration degree of the SPD, the MCU module 3 calculates and analyzes the collected voltage signal and leakage current signal of the SPD to obtain the deterioration degree of the SPD, and outputs the result to the display module 9 for display, so that the user can visually know whether the SPD is in a normal or deteriorated state (the deterioration degree can be visually displayed) or a damaged state.

The SPD leakage current on-line intelligent monitoring device further comprises a power supply module 8 used for providing required corresponding power supply signals for the MCU module 3 and the display module 9, and the output end of the power supply module 8 is connected with the power supply ends of the MCU module 3 and the display module 9. The power module 9 provides a power signal for each module to work normally, the power module 8 can input 24V dc signals or 220V ac signals, and the power module 8 can resist 1.2/506KV surge impact, so that when the SPD is struck by 50KA lightning or surge impact, the power module 8 can still work normally without affecting the normal work of other modules.

The above is only the preferred embodiment of the present invention, and not the scope of the present invention, all the equivalent structures or equivalent flow changes made by the contents of the specification and the drawings or the direct or indirect application in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. An SPD leakage current online intelligent monitoring device comprises a micro-current transmitter, a voltage transmitter, an acquisition module, an MCU module and a resistive current calculation module, wherein the micro-current transmitter is connected with the input end of the acquisition module through a relay normally-closed end, the voltage transmitter is connected with the input end of the acquisition module, the output end of the acquisition module is connected with the input end of the resistive current calculation module, and the output end of the resistive current calculation module is connected with the MCU module.

2. The SPD leakage current on-line intelligent monitoring device of claim 1, further comprising a remote monitoring module and a communication module, wherein the MCU module is connected with the remote monitoring module through the communication module, and sends out MCU data, so as to realize communication between the SPD on-line intelligent monitoring device and the remote monitoring module.

3. The SPD leakage current online intelligent monitoring device of claim 2, further comprising a display module for displaying the deterioration degree of the SPD according to the analysis processing result of the MCU module, wherein the input end of the display module is connected with the output end of the MCU module.

4. The SPD leakage current online intelligent monitoring device of claim 3, further comprising a power module for providing a required corresponding power signal for the MCU module and the display module, wherein an output end of the power module is connected with power ends of the MCU module and the display module.