A low-power monitoring device and system for monitoring leakage current of an insulator

Abstract

The application discloses a low-power-consumption monitoring device, which at least comprises a master processor, a power module, a storage module, a wireless module and a trigger module connected with the master processor; wherein the trigger module is used for generating a trigger level according to the differential current information of two current transformers installed on both sides of an insulator and sending the trigger level to the master processor; the master processor is in a sleep state normally and is used for entering an awakening state when receiving the trigger level sent by the trigger module; and the master processor controls a leakage current collection ring device installed on the top of an insulator string to collect the leakage current flowing through the surface of the insulator when in the awakening state. The application further discloses a corresponding system. The application can realize transient information collection and steady-state information collection and reduces the overall power consumption of the system.

Description

Technical Field

[0001] This invention relates to the field of power technology, and in particular to a low-power monitoring device and system for monitoring leakage current of insulators. Background Technology

[0002] Insulators are specialized insulating devices that play a crucial role in overhead transmission lines. They serve two fundamental functions: supporting the conductors and preventing current from returning to ground. These crucial functions ensure effective insulation. However, factors such as changes in ambient humidity, excessive surface contamination, dirt accumulation, moisture, the formation of dry zones, and the generation of localized electric arcs can all increase insulator leakage current, leading to flashover accidents. This can easily cause faults in the entire transmission line and the entire distribution network, posing a significant threat to the safe operation of the transmission line.

[0003] The online insulator leakage current monitoring system utilizes a leakage current acquisition ring device installed at the top of the insulator string to collect the leakage current flowing through the insulator surface. For transmission line insulators, the monitoring system is generally powered by solar energy, but the stability of the power supply is greatly affected by environmental factors. When the insulator is operating normally, the leakage current range is normal. If the main control module of the monitoring system runs continuously under these conditions, it will result in energy waste. Therefore, low-power operation of the monitoring system is of great significance for the monitoring stability. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a low-power monitoring device and system for monitoring leakage current of insulators, which can realize transient information acquisition and steady-state information acquisition, and reduce the overall power consumption of the system operation.

[0005] In one aspect, the present invention provides a low-power monitoring device according to an embodiment of the invention, comprising at least: a main control processor, a power module, a storage module, a wireless module, and a trigger module connected to the main control processor; wherein:

[0006] The triggering module is used to generate a trigger level based on the received differential current information of the two current transformers installed on both sides of the insulator, and send it to the main control processor.

[0007] The main control processor is normally in a sleep state, and is used to enter a wake-up state when it receives a trigger level sent by the trigger module; and in the wake-up state, it controls the leakage current acquisition ring device installed on the top of the insulator string to collect the leakage current flowing through the surface of the insulator.

[0008] The storage module is used to store the relevant data collected by the main control processor;

[0009] The wireless module is used to send out the leakage current information collected by the main control processor.

[0010] Preferably, the triggering module further includes:

[0011] The mutual inductance signal receiving unit is used to receive the differential current information of two current transformers installed on both sides of the insulator.

[0012] A current-to-voltage conversion unit is used to convert the collected differential current signal into a differential voltage signal;

[0013] A window comparator is used to receive the differential voltage signal as input and compare it with a predetermined window threshold. When the comparison result exceeds the window threshold, a trigger level is generated and sent to the main control processor to wake up the main control processor.

[0014] Preferably, the main control processor further includes:

[0015] A sleep retention unit is used to control the main control processor to remain in a sleep state when no trigger signal is received;

[0016] A fixed-trigger wake-up unit is used to receive a signal from a periodic timer and trigger the main control processor to enter the wake-up state each time the timer expires.

[0017] The transient trigger wake-up unit is used to trigger the main control processor to enter the wake-up state after receiving the trigger level sent by the trigger module;

[0018] The wake-up processing unit is used to control the leakage current acquisition ring device to work and acquire the leakage current flowing through the surface of the insulator when the main control processor is in the wake-up state.

[0019] Preferably, the main control processor further includes:

[0020] The hibernation recovery unit is used to control the leakage current acquisition ring device to stop working after the wake-up processing unit collects the leakage current that meets the protection requirements, and to return to the hibernation state after the wireless module sends out the collected leakage current information.

[0021] Accordingly, the present invention also discloses a low-power monitoring system for monitoring insulator leakage current, which includes at least:

[0022] Two current transformers are installed on both sides of the insulator to collect the mutual inductance current on both sides of the insulator and form a differential current.

[0023] A leakage current acquisition ring device, installed on top of the insulator string, is used for controlled acquisition of leakage current flowing through the surface of the insulator; and

[0024] The aforementioned low-power monitoring device is connected to the two current transformers and the leakage current acquisition loop device.

[0025] Implementing the embodiments of the present invention has the following beneficial effects:

[0026] This invention provides a low-power monitoring device and system for monitoring insulator leakage current. By employing a triggering device based on the differential protection principle, when the insulator is in a normal state and the differential current across the insulator is normal, the MCU is not immediately triggered to wake up. Instead, the main control MCU operates at preset fixed time intervals, and the collected information is used by artificial intelligence algorithms to predict the insulator's state. When the insulator leakage current is abnormal, the currents across the insulator become unbalanced, leading to a differential current greater than zero or a certain threshold, thus triggering a trigger level and waking up the main control MCU, thereby achieving transient signal acquisition. This allows the low-power monitoring device and leakage current acquisition loop to operate in a sleep state most of the time, achieving low-power operation of the monitoring system.

[0027] Meanwhile, the triggering device uses the differential signal collected by the current transformer, that is, it adopts a passive triggering method to wake up the main controller, which further reduces the overall power consumption of the system. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of an embodiment of a low-power monitoring system for monitoring leakage current of insulators provided by the present invention.

[0030] Figure 2 for Figure 1 Schematic diagram of a low-to-medium power consumption monitoring device;

[0031] Figure 3 for Figure 2 A schematic diagram of the trigger module;

[0032] Figure 4 for Figure 3 The circuit schematic of the medium window comparator;

[0033] Figure 5 for Figure 3 A schematic diagram of the output level waveform of the window comparator;

[0034] Figure 6 for Figure 2 A schematic diagram of the main control processor. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] It should also be noted that, in order to avoid obscuring the invention with unnecessary details, only the structures and / or processing steps closely related to the solution according to the invention are shown in the accompanying drawings, while other details that are not closely related to the invention are omitted.

[0037] like Figure 1 The diagram shows a schematic representation of an embodiment of a low-power monitoring system for monitoring insulator leakage current provided by the present invention; in this embodiment, the system includes at least:

[0038] Two current transformers 2 are installed on both sides of the insulator to collect the mutual inductance current on both sides of the insulator and form a differential current;

[0039] Leakage current acquisition ring device 3, installed on top of the insulator string, is used for controlled acquisition of leakage current flowing through the surface of the insulator; and

[0040] The aforementioned low-power monitoring device 1 is connected to the two current transformers and the leakage current acquisition loop device. It is used to determine, at least based on the differential current acquired by the current transformer 2, whether it is necessary to initiate the acquisition of leakage current flowing through the insulator surface, and to achieve a low-power acquisition process. The low-power monitoring device 1 will be described in detail later.

[0041] like Figure 2 The diagram shows a schematic representation of an embodiment of a low-power monitoring device provided by the present invention. In this embodiment, the low-power monitoring device 1 includes at least: a main control processor (MCU) 10, a power module 12, a storage module 13, a wireless module 14, and a trigger module 11 connected to the main control processor 10; wherein:

[0042] The trigger module 11 is used to generate a trigger level based on the received differential current information of the two current transformers installed on both sides of the insulator, and send it to the main control processor.

[0043] The main control processor 10 is normally in a sleep state, and is used to enter a wake-up state when it receives a trigger level sent by the trigger module; and in the wake-up state, it controls the leakage current acquisition ring device installed on the top of the insulator string to collect the leakage current flowing through the surface of the insulator.

[0044] Storage module 13 is used to store the corresponding data collected by the main control processor;

[0045] The wireless module 14 is used to send out the leakage current information collected by the main control processor.

[0046] More specifically, such as Figure 3 As shown, the trigger module 11 further includes:

[0047] The mutual inductance signal receiving unit 110 is used to receive the differential current information of two current transformers installed on both sides of the insulator.

[0048] The current-to-voltage conversion unit 111 is used to convert the collected differential current signal into a differential voltage signal;

[0049] Window comparator 112 is used to receive the differential voltage signal as input and compare it with a predetermined window threshold. When the comparison result exceeds the window threshold, a trigger level is generated and sent to the main control processor to wake up the main control processor.

[0050] It is understood that differential current information is used to implement the differential protection function in this invention. Specifically, by inputting the vector difference of the currents across the two ends of the CT (current transformer), the operating element is activated when the set operating value is reached. Differential protection is based on the principle that "the sum of the currents flowing into a node in a circuit equals zero." Differential protection treats the protected electrical equipment as a node. Under normal conditions, the current flowing into the protected equipment is equal to the current flowing out, and the differential current is zero. When a fault occurs in the equipment, the current flowing into the protected equipment is not equal to the current flowing out, and the differential current is greater than zero. When the differential current exceeds the setting value of the differential protection device, the circuit breakers on each side of the protected equipment trip, disconnecting the power supply to the faulty equipment.

[0051] In this invention, the triggering device is based on the principle that when the insulator is in a normal state, the differential current on both sides of the insulator is 0 or lower than a certain threshold. When the leakage current of the insulator is abnormal, the current on both sides of the insulator becomes unbalanced, which in turn causes the differential current on both sides of the insulator to be greater than zero or greater than a certain threshold, thereby triggering the generation of a trigger level, waking up the main control MCU, and thus realizing transient signal acquisition.

[0052] In this invention, two current transformers are installed on both sides of the transformer tower. A current transformer is an instrument that converts a large primary current into a small secondary current for measurement based on the principle of electromagnetic induction. A current transformer consists of a closed iron core and windings. Its primary winding has very few turns and is connected in series with the line whose current needs to be measured. Therefore, it often carries the entire current of the line. The secondary winding has more turns and is connected in series with the measuring instrument and protection circuit. When the current transformer is working, its secondary circuit is always closed. Therefore, the impedance of the series coil of the measuring instrument and protection circuit is very small, and the operating state of the current transformer is close to a short circuit. The current transformer converts a large primary current into a small secondary current for measurement; the secondary side must not be open-circuited.

[0053] The collected differential current is processed by a current-to-voltage conversion circuit to output a suitable voltage signal. The voltage signal is a sine wave, and a high level is generated when the peak or trough exceeds the set value. Therefore, the comparator uses a window comparator circuit.

[0054] A window comparator, also known as a dual-threshold comparator, has two threshold levels and can detect whether the level of an input analog signal falls between two given threshold levels. Window comparators are very useful in component selection and classification, or in monitoring and controlling production sites. For example... Figure 4 As shown, when the input voltage U i Greater than threshold U RH Or less than U RL At any given time, only one diode will be turned on, resulting in a high-level output. This only occurs when the input voltage is between U and U. RH and U RL During this period, both D1 and D2 are cut off, resulting in a low output level; the waveform diagram of the output level can be found in [reference needed]. Figure 5 As shown. When the output is high, it triggers the main control processor to wake up.

[0055] More specifically, the main control processor 10 further includes:

[0056] The sleep retention unit 100 is used to control the main control processor to remain in a sleep state when no trigger signal is received;

[0057] The fixed trigger wake-up unit 101 is used to receive the signal of a periodic timer and trigger the main control processor to enter the wake-up state each time the timer expires;

[0058] The transient trigger wake-up unit 102 is used to trigger the main control processor to enter the wake-up state after receiving the trigger level sent by the trigger module;

[0059] The wake-up processing unit 103 is used to control the leakage current acquisition ring device to work and acquire the leakage current flowing through the surface of the insulator when the main control processor is in the wake-up state.

[0060] The hibernation recovery unit 104 is used to control the leakage current acquisition ring device to stop working after the wake-up processing unit collects the leakage current that meets the protection requirements, and to return to the hibernation state after the wireless module sends out the collected leakage current information.

[0061] It is understood that, in the embodiments of the present invention, the wake-up processing unit 103 adopts two wake-up methods corresponding to the acquisition methods, specifically: transient information acquisition method and steady-state information acquisition method.

[0062] The transient acquisition process involves non-fixed operating time. When the trigger module generates a trigger level, the MCU ends its sleep state and automatically performs transient waveform recording upon waking. Due to the large amount of transient waveform data, it needs to be stored in a memory chip. After acquisition, the data is wirelessly transmitted back to the backend database. When the insulator leaks current, the current transformer coils on both sides of the tower collect the current to obtain the differential current. This current is then converted into a suitable output voltage by a current-to-voltage conversion circuit. After passing through a comparator circuit, a high level is generated, triggering the transient waveform recorder to operate.

[0063] Steady-state data acquisition is performed at fixed time intervals. A clock chip is used to set the time interval, control the main power supply, and automatically wake up the MCU to complete the steady-state signal acquisition. The data is then wirelessly transmitted back to the backend database, achieving low-power acquisition.

[0064] Understandably, steady-state data acquisition is necessary. The condition of an insulator is closely related to its leakage current. A differential current failing to reach its set value does not necessarily mean the insulator is in good condition; even minor damage to the insulator can lead to changes in electrical quantities. Therefore, artificial intelligence algorithms can be used to predict the condition based on the acquired steady-state data, thereby enabling insulator maintenance.

[0065] Implementing the embodiments of the present invention has the following beneficial effects:

[0066] This invention provides a low-power monitoring device and system for monitoring insulator leakage current. By employing a triggering device based on the differential protection principle, when the insulator is in a normal state and the differential current across the insulator is normal, the MCU is not immediately triggered to wake up. Instead, the main control MCU operates at preset fixed time intervals, and the collected information is used by artificial intelligence algorithms to predict the insulator's state. When the insulator leakage current is abnormal, the currents across the insulator become unbalanced, leading to a differential current greater than zero or a certain threshold, thus triggering a trigger level and waking up the main control MCU, thereby achieving transient signal acquisition. This allows the low-power monitoring device and leakage current acquisition loop to operate in a sleep state most of the time, achieving low-power operation of the monitoring system.

[0067] Meanwhile, the triggering device uses the differential signal collected by the current transformer, that is, it adopts a passive triggering method to wake up the main controller, which further reduces the overall power consumption of the system.

[0068] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of the claims of the present invention. Therefore, any equivalent changes or modifications made without departing from the spirit disclosed in the present invention should be included within the scope of the claims of the present invention.

Claims

1. A low-power monitoring device, characterized in that, It includes at least: a main control processor, a power module, a storage module, a wireless module, and a trigger module connected to the main control processor; wherein: The triggering module is used to generate a trigger level based on the received differential current information from two current transformers installed on both sides of the insulator, and send it to the main control processor. The two current transformers are installed on both sides of the transformer tower. When the leakage current of the insulator is abnormal, the current on both sides of the insulator is unbalanced, causing the differential current on both sides of the insulator to be greater than zero or greater than a predetermined threshold, thereby triggering the generation of the trigger level and waking up the main control processor. The main control processor is normally in a sleep state, and is used to enter a wake-up state when it receives a trigger level sent by the trigger module; and in the wake-up state, it controls the leakage current acquisition ring device installed on the top of the insulator string to collect the leakage current flowing through the surface of the insulator. The storage module is used to store the relevant data collected by the main control processor; The wireless module is used to send out the leakage current information collected by the main control processor.

2. The apparatus as claimed in claim 1, characterized in that, The triggering module further includes: The mutual inductance signal receiving unit is used to receive the differential current information of two current transformers installed on both sides of the insulator. A current-to-voltage conversion unit is used to convert the collected differential current signal into a differential voltage signal; A window comparator is used to receive the differential voltage signal as input and compare it with a predetermined window threshold. When the comparison result exceeds the window threshold, a trigger level is generated and sent to the main control processor to wake up the main control processor.

3. The apparatus as described in claim 2, characterized in that, The main control processor further includes: A sleep retention unit is used to control the main control processor to remain in a sleep state when no trigger signal is received; A fixed-trigger wake-up unit is used to receive a signal from a periodic timer and trigger the main control processor to enter the wake-up state each time the timer expires. The transient trigger wake-up unit is used to trigger the main control processor to enter the wake-up state after receiving the trigger level sent by the trigger module; The wake-up processing unit is used to control the leakage current acquisition ring device to work and acquire the leakage current flowing through the surface of the insulator when the main control processor is in the wake-up state.

4. The apparatus according to any one of claims 1 to 3, characterized in that, The main control processor further includes: The hibernation recovery unit is used to control the leakage current acquisition ring device to stop working after the wake-up processing unit collects the required leakage current, and to return to hibernation state after the wireless module sends out the collected leakage current information.

5. A low-power monitoring system for monitoring leakage current of insulators, characterized in that, At least including: Two current transformers are installed on both sides of the insulator to collect the mutual inductance current on both sides of the insulator and form a differential current. A leakage current acquisition ring device is installed on the top of the insulator string to collect the leakage current flowing through the surface of the insulator in a controlled manner. as well as The low-power monitoring device as described in any one of claims 1 to 4 is connected to the two current transformers and the leakage current acquisition loop device.

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