A monitoring device and method for the connection state of the current commutation valve's diversion busbar

Abstract

The present invention discloses a monitoring device and a monitoring method for the connection state of a current commutation valve's diversion busbar. The current commutation valve includes a diversion busbar connection end, and the diversion busbar connection end is connected to components in the current commutation valve through a plurality of fastening bolts. The device includes: a temperature sensor, arranged above the diversion busbar connection end for monitoring the temperature of the connection end; a fastening force sensor for monitoring the fastening force of the fastening bolts; and a controller for judging the fastening state of the fastening bolts according to the change directions of the temperature and the fastening force. By implementing the present invention, a temperature sensor is set to monitor the temperature of the diversion busbar connection end, a fastening force sensor is set to monitor the fastening force of the bolts, and by simultaneously monitoring the temperature and the fastening force, the controller fuses the monitoring results of the two to comprehensively judge the fastening state of the fastening bolts on the connection end. Thus, the monitoring device helps to more accurately judge the fastening state by effectively fusing the monitoring results of multiple physical quantities including temperature and fastening force.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent sensing and Internet of Things, and particularly relates to a monitoring device and method for the connection state of a current-commutating valve diversion busbar. Background Art

[0002] The construction of the backbone grid and networking of UHV DC transmission is an important foundation for realizing the strategic transformation of energy development and promoting the meeting of global power demand in a clean and green way. With the successive commissioning of numerous high-voltage DC transmission lines, higher requirements are put forward for the safe and reliable operation of the core equipment of high-voltage DC converter stations. The current-commutating valve is a core equipment in the UHV DC converter station, which is expensive and plays an important role. Once a failure occurs in the current-commutating valve equipment, it will not only lead to the outage of DC transmission, but in severe cases, it may cause the current-commutating valve or the valve hall to catch fire, thus triggering major safety accidents.

[0003] When the current-commutating valve is operating, the saturation reactor will generate continuous vibrations, which will drive the connection ends of the diversion busbar connected thereto to vibrate, and then conduct the vibrations to other valve components. Due to the strong vibrations of the reactor, the fastening bolts at the connection ends of the diversion busbar may become loose, increasing the contact resistance and further causing local overheating. At present, temperature sensors are mostly used to monitor the temperature, however, there may be problems of misjudgment when using temperature sensors for monitoring. Summary of the Invention

[0004] In view of this, embodiments of the present invention provide a monitoring device and method for the connection state of a current-commutating valve diversion busbar to solve the technical problem of misjudgment in monitoring the current-commutating valve using temperature sensors in the prior art.

[0005] The technical solutions provided by the embodiments of the present invention are as follows:

[0006] In a first aspect of an embodiment of the present invention, there is provided a monitoring device for the connection state of a current-commutating valve diversion busbar. The current-commutating valve includes a connection end of the diversion busbar, and the connection end of the diversion busbar is connected to components in the current-commutating valve through a plurality of fastening bolts. The monitoring device includes: a temperature sensor, arranged above the connection end of the diversion busbar, for monitoring the temperature of the connection end of the diversion busbar; a fastening force sensor, for monitoring the fastening force of the fastening bolts; and a controller, connected to the temperature sensor and the fastening force sensor, for judging the fastening state of the fastening bolts according to the change directions of the temperature and the fastening force.

[0007] Optionally, the monitoring device for the connection state of the current-commutating valve diversion busbar further includes: a temperature difference energy harvesting module, for converting the thermal energy generated by the current flowing through the connection end of the diversion busbar in the current-commutating valve into electrical energy to supply power to the temperature sensor and the fastening force sensor.

[0008] Optionally, the monitoring device for the connection state of the current-commutating valve diversion busbar further includes: a vibration energy harvesting module, configured to convert the vibration energy generated by the vibration of the connection end of the diversion busbar into electrical energy to supply power to the temperature sensor and the fastening force sensor.

[0009] Optionally, the monitoring device for the connection state of the current-commutating valve diversion busbar further includes: an energy storage module, connected to the temperature difference energy harvesting module and / or the vibration energy harvesting module, the temperature sensor, and the fastening force sensor, storing the electrical energy converted by the temperature difference energy harvesting module and / or the vibration energy harvesting module, and supplying power to the temperature sensor and the fastening force sensor.

[0010] Optionally, the monitoring device for the connection state of the current-commutating valve diversion busbar further includes: a temperature difference energy harvesting management module and / or a vibration energy harvesting management module. The controller includes a main control unit, and the main control unit is connected to the temperature difference energy harvesting management module and / or the vibration energy harvesting management module, sending a first PWM signal to the temperature difference energy harvesting management module and a second PWM signal to the vibration energy harvesting management module; the temperature difference energy harvesting management module includes a first converter, and the first converter converts the electrical energy converted by the temperature difference energy harvesting module according to the first PWM signal and then inputs it into the energy storage module; the vibration energy harvesting management module includes a second converter, and the second converter converts the electrical energy converted by the vibration energy harvesting module according to the second PWM signal and then inputs it into the energy storage module.

[0011] Optionally, the temperature difference energy harvesting management module further includes: a first switch, the vibration energy harvesting management module further includes: a second switch, the controller further includes: a switch control unit and an energy storage evaluation unit. Both the switch control unit and the energy storage evaluation unit are connected to the main control unit. The switch control unit is connected to the first switch and the second switch, and the energy storage evaluation unit is connected to the energy storage module to obtain the parameters of the energy storage module. When the parameters are higher than the high limit value, an overvoltage signal is generated to the main control unit, and the main control unit generates a disconnection signal to the switch control unit according to the overvoltage signal, and the switch control unit disconnects the first switch and the second switch according to the disconnection signal; when the parameters are lower than the low limit value, an undervoltage signal is generated to the main control unit, and the main control unit controls the temperature sensor and the fastening force sensor to enter the sleep state according to the undervoltage signal.

[0012] Optionally, the switch control unit is connected to the temperature difference energy harvesting module and the vibration energy harvesting module. The switch control unit obtains a first voltage signal of the electrical energy in the temperature difference energy harvesting module, and when the first voltage signal is lower than a first threshold value, disconnects the first switch; the switch control unit obtains a second voltage signal of the electrical energy in the vibration energy harvesting module, and when the second voltage signal is lower than a second threshold value, disconnects the second switch.

[0013] In a second aspect of the embodiments of the present invention, a method for monitoring the connection state of the current-carrying busbar of a converter valve is provided. The converter valve includes a connection end of the current-carrying busbar, and the connection end of the current-carrying busbar is connected to components in the converter valve through a plurality of fastening bolts. The monitoring method includes: obtaining the fastening force of the fastening bolts; determining whether the fastening force has changed compared with the steady-state value of the fastening force; when the fastening force has changed compared with the steady-state value of the fastening force, determining the fastening state of the fastening bolts according to the change directions of the fastening force and the temperature of the connection end of the current-carrying busbar.

[0014] Optionally, when the fastening force has changed compared with the steady-state value of the fastening force, determining the fastening state of the fastening bolts according to the change directions of the fastening force and the temperature of the connection end of the current-carrying busbar includes: when the fastening force shows an upward trend compared with the steady-state value of the fastening force, determining whether the fastening force is less than or equal to the upper limit of the fastening force; when it is greater than the upper limit of the fastening force, issuing a warning of over-limit fastening force.

[0015] Optionally, the method for monitoring the connection state of the current-carrying busbar of the converter valve further includes: when it is less than or equal to the upper limit of the fastening force, determining whether the temperature of the connection end of the current-carrying busbar is greater than the steady-state temperature value; when it is greater than the steady-state temperature value, determining that the fastening force is normal; when it is equal to or lower than the steady-state value, issuing a warning of fastening of the fastening bolts.

[0016] Optionally, when the fastening force has changed compared with the steady-state value of the fastening force, determining the fastening state of the fastening bolts according to the change directions of the fastening force and the temperature of the connection end of the current-carrying busbar includes: when the fastening force shows a downward trend compared with the steady-state value of the fastening force, determining whether the fastening force is greater than or equal to the lower limit of the fastening force; when it is less than the lower limit of the fastening force, issuing a warning of over-limit fastening force.

[0017] Optionally, the method for monitoring the connection state of the current-carrying busbar of the converter valve further includes: when it is greater than or equal to the lower limit of the fastening force, determining whether the temperature of the connection end of the current-carrying busbar is lower than the steady-state temperature value; when it is greater than or equal to the steady-state temperature value, issuing a warning of loosening of the fastening bolts; when it is lower than the steady-state value, determining that the fastening force is normal.

[0018] The technical solution of the present invention has the following advantages:

[0019] The device for monitoring the connection state of the current-carrying busbar of the converter valve provided by the embodiments of the present invention is provided with a temperature sensor to monitor the temperature of the connection end of the current-carrying busbar, and a fastening force sensor to monitor the fastening force of the bolts. By simultaneously monitoring the temperature and the fastening force, the monitoring results of the two are fused by a controller to comprehensively determine the fastening state of the fastening bolts at the connection end of the current-carrying busbar. Thus, by effectively fusing the monitoring results of multiple physical quantities including temperature and fastening force, the monitoring device helps to more accurately determine the fastening state.

[0020] The method for monitoring the connection state of the current-conducting busbar of a converter valve provided by an embodiment of the present invention monitors the temperature and the fastening force simultaneously, and the controller fuses the monitoring results of the two to comprehensively judge the fastening state of the fastening bolts at the connection end of the current-conducting busbar. Thus, by effectively fusing the monitoring results of multiple physical quantities including temperature and fastening force, this monitoring method helps to more accurately judge the fastening state.

[0021] The method for monitoring the connection state of the current-conducting busbar of a converter valve provided by an embodiment of the present invention sets a temperature difference energy harvesting module and a vibration energy harvesting module to convert the energy in the current-conducting busbar into electric energy. At the same time, a energy storage module is set to store this electric energy to supply power to the temperature sensor and the fastening force sensor, thereby reducing the dependence of the sensor node on the battery and even realizing battery-free operation, providing a new power supply solution for the flexible deployment and long-term reliable operation of the sensing node. Description of the Drawings

[0022] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0023] Figure 1 It is a structural block diagram of a specific example of the device for monitoring the connection state of the current-conducting busbar of a converter valve in an embodiment of the present invention;

[0024] Figure 2 It is a structural block diagram of a specific example of a converter valve in an embodiment of the present invention;

[0025] Figure 3 It is a flowchart of the fastening state monitoring in the device for monitoring the connection state of the current-conducting busbar of a converter valve in an embodiment of the present invention;

[0026] Figure 4 It is a structural block diagram of another specific example of the device for monitoring the connection state of the current-conducting busbar of a converter valve in an embodiment of the present invention;

[0027] Figure 5 It is a structural block diagram of another specific example of the device for monitoring the connection state of the current-conducting busbar of a converter valve in an embodiment of the present invention;

[0028] Figure 6 It is a flowchart of a specific example of the method for monitoring the connection state of the current-conducting busbar of a converter valve in an embodiment of the present invention. Detailed Embodiments

[0029] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0030] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and should not be construed as indicating or implying relative importance.

[0031] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can also be the communication inside two elements. It can be a wireless connection or a wired connection. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0032] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0033] The commutation valve current-carrying busbar is used to connect the main circuit components of the commutation valve, such as thyristor press-fitting assemblies, saturable reactors, etc. The connection state of the current-carrying busbar, that is, the connection state between the end of the current-carrying busbar and the wiring end of the main circuit component, directly affects the safe and stable operation of the commutation valve. Due to the passage of large currents, when the connection state of the current-carrying busbar is not good, the contact resistance is relatively large, and the heat generation is serious. The positive temperature effect of the contact resistance causes the temperature of the connection end to rise further. In severe cases, thermal breakdown may occur, endangering the safe operation of the components and the entire commutation valve. Taking the connection state monitoring of the saturable reactor of the commutation valve and the current-carrying busbar as an example, the monitoring device and method of the present invention are described, and the device and method are also applicable to the connection state monitoring of other components and the current-carrying busbar.

[0034] An embodiment of the present invention provides a device for monitoring the connection state of a commutation valve current-carrying busbar. The commutation valve includes a connection end of the current-carrying busbar, and the connection end of the current-carrying busbar is connected to the components in the commutation valve through a plurality of fastening bolts, such as Figure 1As shown in the figure, the monitoring device includes: a temperature sensor, disposed above the connection end of the current-carrying busbar, for monitoring the temperature of the connection end; a fastening force sensor, for monitoring the fastening force of the fastening bolt; and a controller (not shown in the figure), connected to the temperature sensor and the fastening force sensor, for judging the fastening state of the fastening bolt according to the change directions of the temperature and the fastening force.

[0035] Specifically, as Figure 2 shown in the figure, it is a connection schematic diagram of the saturable reactor and the current-carrying busbar. The saturable reactor is a vibration source. Due to their rigid connection, the connection end of the current-carrying busbar connected thereto will also vibrate. A plurality of fastening bolts are installed on the connection end of the current-carrying busbar. The bolts may become loose due to vibration. Therefore, it is necessary to monitor the fastening state of the fastening bolts during the operation of the converter valve.

[0036] Among them, the temperature sensor is fixed above the connection end of the current-carrying busbar through a metal substrate, and the temperature measurement can be realized by contacting the bottom plate. The fastening force sensor measures the fastening force by embedding a collar-type sensor into the bolt fastener, or a flat gasket pressure-type fastening force sensor is adopted. Since a plurality of fastening bolts are provided on the connection end of the current-carrying busbar, a fastening force sensor can be provided on each fastening bolt, or several of them can be selected to be provided with fastening force sensors. The number of fastening force sensors is not limited in the embodiment of the present invention. Embedded micro wireless intelligent sensors can be selected for both the temperature sensor and the fastening force sensor.

[0037] For a high-voltage converter valve, its internal key components include semiconductor switching devices, voltage equalizing / buffering circuits, trigger and monitoring electronic system circuits, connection busbars, and fittings and insulators for installation, etc. The operating temperature of these components can characterize their health status, and early warning of possible aging and faults can be realized by monitoring their temperatures. Therefore, a plurality of temperature sensors can also be provided in the monitoring device for the connection state of the converter valve current-carrying busbar to monitor the operating temperatures of other components in the converter valve, and the controller obtains the operating temperature for aging and fault judgment.

[0038] The monitoring device for the connection state of the converter valve current-carrying busbar provided by the embodiment of the present invention sets a temperature sensor to monitor the temperature of the connection end of the current-carrying busbar, sets a fastening force sensor to monitor the bolt fastening force, monitors the temperature and the fastening force simultaneously, and the controller fuses the monitoring results of the two to comprehensively judge the fastening state of the fastening bolts on the connection end of the current-carrying busbar. Thus, the monitoring device helps to more accurately judge the fastening state by effectively fusing the monitoring results of multiple physical quantities including temperature and fastening force.

[0039] In an embodiment, as Figure 3As shown, after the controller receives the tightening force and temperature, the judgment of the tightening state can be carried out according to the following process:

[0040] 1. Judge whether the tightening force F has changed compared with the previous steady-state value;

[0041] 2. If the tightening force F shows an upward trend:

[0042] a. Judge whether F ≤ F_max?

[0043] b. If not (F > F_max), it means that F exceeds the upper limit F_max, and the system issues a warning for over-limit tightening force. The tightening force is too large, and the judgment ends;

[0044] c. If F does not exceed the upper limit F_max (F ≤ F_max), it cannot be simply judged that F is normal in all aspects. It is necessary to combine the trend judgment of the temperature T of the connection end of the diversion busbar;

[0045] If the end temperature T rises, it is judged that the increase in the tightening force is due to the thermal expansion of the bolt and the busbar caused by the temperature rise, and the tightening force F is normal, and the monitoring continues;

[0046] If the end temperature T does not rise and the tightening force and temperature change in the opposite direction, a warning is issued for the force conduction of the components adjacent to the busbar.

[0047] 3. If the tightening force F shows a downward trend:

[0048] a. First, judge whether F ≥ F_min;

[0049] b. If not (F < F_min), it means that F exceeds the lower limit F_min, and the system issues a warning for over-limit tightening force. The bolt is loose, and the judgment ends;

[0050] c. If F does not exceed the lower limit F_min (F ≥ F_min), it cannot be simply judged that F is normal in all aspects. It is necessary to combine the trend judgment of the end temperature T;

[0051] If the end temperature T drops, it is judged that the decrease in the tightening force is due to the cold shrinkage of the bolt and the busbar caused by the temperature drop, and the tightening force F is normal, and the monitoring continues;

[0052] If the end temperature T does not drop and the tightening force and temperature change in the opposite direction, a warning is issued for the loosening of the bolt tightening force.

[0053] In one embodiment, since the converter valve is a high-voltage and large-current environment, it is very challenging to supply power to the sensing node by taking energy at a high potential. If lithium batteries are used for power supply, the safety is poor and there is an explosion risk. At the same time, regularly replacing a large number of batteries greatly increases the operation and maintenance costs of the converter valve equipment. Thus, as Figure 1 andFigure 4 As shown in the figure, a temperature difference energy harvesting module and a vibration energy harvesting module are provided in the monitoring device for the connection state of the converter valve busbar. By using the environmental energy such as the vibration of the connection end of the converter valve busbar and the heat generated due to current conduction, electrical energy can be obtained, thereby reducing the dependence of the sensing node on the battery and even realizing battery-free operation, providing a new power supply solution for the flexible deployment and long-term reliable operation of the sensing node.

[0054] Specifically, the temperature difference energy harvesting module is used to convert the thermal energy generated by the current conduction at the connection end of the converter valve busbar into electrical energy. Among them, the temperature difference energy harvesting module includes a thermoelectric generator. The thermoelectric generator is in contact with the connection end of the converter valve busbar through a heat-conducting metal bottom plate, and the conduction thermal energy generated based on the temperature difference between the connection end temperature and the ambient temperature can be used to generate electrical energy. For the thermoelectric generator, the conversion between thermal energy and electrical energy can be achieved based on the Seebeck effect. The vibration energy harvesting module is used to convert the vibration energy generated by the vibration of the connection end of the converter valve busbar into electrical energy. The vibration energy harvesting module can use a piezoelectric crystal to realize the conversion between the vibration energy and electrical energy generated by the connection end of the converter valve busbar, or other methods can also be used. The embodiments of the present invention do not limit this.

[0055] To facilitate the power supply to the temperature sensor and the vibration sensor, as Figure 4 shown, an energy storage module is provided in the monitoring device. The converted electrical energy is stored through the energy storage module and used to supply power to the temperature sensor and the vibration sensor uniformly based on the stored electrical energy. Among them, the energy storage module is connected to the temperature difference energy harvesting module, the vibration energy harvesting module, the temperature sensor, and the fastening force sensor, stores the electrical energy converted by the temperature difference energy harvesting module and the vibration energy harvesting module, and supplies power to the temperature sensor and the fastening force sensor. Specifically, the energy storage module uses a super capacitor to store electrical energy, or other methods can also be used. The embodiments of the present invention do not limit this.

[0056] In one embodiment, as Figure 4 shown, the monitoring device for the connection state of the converter valve busbar further includes: a temperature difference energy harvesting management module and a vibration energy harvesting management module. The controller includes a main control unit. The main control unit is connected to the temperature difference energy harvesting management module and the vibration energy harvesting management module, and sends a first PWM (Pulse Width Modulation) signal to the temperature difference energy harvesting management module and a second PWM signal to the vibration energy harvesting management module; as Figure 5 shown, the temperature difference energy harvesting management module includes a first converter. The first converter converts the electrical energy converted by the temperature difference energy harvesting module according to the first PWM signal and then inputs it into the energy storage module; the vibration energy harvesting management module includes a second converter. The second converter converts the electrical energy converted by the vibration energy harvesting module according to the second PWM signal and then inputs it into the energy storage module.

[0057] Specifically, since the energy harvesting from temperature difference is DC and the energy harvesting from vibration is AC, the first converter includes a DC / DC converter, and the second converter includes an AC / DC converter and a DC / DC converter connected in sequence. Among them, the converter includes multiple switching tubes, and the conduction of the switching tubes can be adjusted by the PWM signal output by the main control unit, so as to realize the stable and normal operation of the converter.

[0058] In one embodiment, as Figure 4 、 Figure 5 shown, the temperature difference energy harvesting management module further includes: a first switch, the vibration energy harvesting management module further includes: a second switch, and the controller further includes: a switch control unit and an energy storage evaluation unit. Both the switch control unit and the energy storage evaluation unit are connected to the main control unit. The switch control unit is connected to the first switch and the second switch, and the energy storage evaluation unit is connected to the energy storage module to obtain the parameters of the energy storage module. When the parameters are higher than the high limit value, an overvoltage signal is generated to the main control unit, and the main control unit generates a disconnection signal to the switch control unit according to the overvoltage signal. The switch control unit disconnects the first switch and the second switch according to the disconnection signal; when the parameters are lower than the low limit value, an undervoltage signal is generated to the main control unit, and the main control unit controls the temperature sensor and the fastening force sensor to enter the sleep state according to the undervoltage signal.

[0059] Specifically, both the first switch and the second switch are power switches. When the energy storage module is a supercapacitor, the energy storage evaluation unit evaluates the state of charge (SOC) of the supercapacitor according to the voltage and current of the supercapacitor. At the same time, it can also judge whether the supercapacitor is in an overvoltage state or an undervoltage state according to the voltage signal. If it is in an overvoltage state, it indicates that the environmental energy is excessive. At this time, the overvoltage state is fed back to the switch control unit through the main control unit, and the switch control unit sends a disconnection signal to disconnect the first switch and the second switch. If the supercapacitor is in an undervoltage state, it indicates that its voltage value is lower than the preset minimum value, that is, the low limit value. This information is fed back to the main control unit, and the main control unit judges that the environmental energy cannot meet the sensing work in this case. The main control unit will command the temperature sensor and the fastening force sensor to enter the sleep state and wait for the supercapacitor to charge.

[0060] In one embodiment, the switch control unit is connected to the temperature difference energy harvesting module and the vibration energy harvesting module. The switch control unit obtains the first voltage signal of the electric energy in the temperature difference energy harvesting module. When the first voltage signal is lower than the first threshold value, the first switch is disconnected; the switch control unit obtains the second voltage signal of the electric energy in the vibration energy harvesting module. When the second voltage signal is lower than the second threshold value, the second switch is disconnected.

[0061] Specifically, as Figure 5 shown, the switch control unit acquires the voltage signals (V teg and V vib ) of the temperature difference energy harvesting module and the vibration energy harvesting module. When the temperature difference power generation is too weak to cause V teg to be lower than the minimum starting voltage of the first converter, and at this time V vib is normal, the switch control unit sends a signal to disconnect the first switch, thereby temporarily disconnecting the temperature difference power generation and preventing the electric energy of the super capacitor from flowing back into the temperature difference energy harvesting management module. When the vibration power generation is too weak to cause V vib to be lower than the minimum starting voltage of the second converter, and at this time V teg is normal, the switch control unit sends a signal to disconnect the second switch, thereby temporarily disconnecting the vibration power generation and preventing the electric energy of the super capacitor from flowing back into the vibration energy harvesting management module. When V teg and V vib are both lower than the minimum starting voltage of the first converter or the second converter, the switch control unit will send a disconnection signal to the first switch and the second switch, thereby disconnecting the two energy harvesting modules simultaneously. At this time, the temperature sensor and the fastening force sensor enter the sleep mode due to the lack of power supply.

[0062] An embodiment of the present invention further provides a method for monitoring the connection state of the diversion busbar of a converter valve. The converter valve includes a diversion busbar connection end, and the diversion busbar connection end is connected to the components in the converter valve through a plurality of fastening bolts. As Figure 6 shown, the monitoring method includes the following steps:

[0063] Step S101: Acquire the fastening force of the fastening bolt. Specifically, a fastening force sensor is used to acquire the fastening force of the fastening bolt, or other methods can also be used to acquire the fastening force. The embodiment of the present invention does not limit this. While acquiring the fastening force, the temperature of the diversion busbar connection end can also be acquired for subsequent auxiliary judgment of the fastening state.

[0064] Step S102: Determine whether the fastening force has changed compared to the fastening force steady state value. Among them, the fastening force steady state value can be the fastening force of the fastening bolt of the converter valve acquired before the current moment, that is, the fastening force has been in a stable state before the current moment, so the previous fastening force can be used as the steady state value. In addition, the fastening force steady state value can also be the fastening force steady state value acquired historically and saved to the corresponding converter valve.

[0065] Step S103: When the tightening force changes compared with the steady-state value of the tightening force, judge the tightening state of the tightening bolt according to the change directions of the tightening force and the temperature of the connection end of the current-carrying busbar. Among them, when the tightening force changes, the tightening state can be judged in combination with the temperature change. When specifically judging, the tightening state can be judged through the change direction of the tightening force and the change direction of the temperature.

[0066] The method for monitoring the connection state of the current-carrying busbar of the converter valve provided by the embodiment of the present invention monitors the temperature and the tightening force at the same time, and the controller fuses the monitoring results of the two to comprehensively judge the tightening state of the tightening bolt at the connection end of the current-carrying busbar. Thus, by effectively fusing the monitoring results of multiple physical quantities including temperature and tightening force, this monitoring method helps to more accurately judge the tightening state.

[0067] In one embodiment, as Figure 3 shown, when the tightening force changes compared with the steady-state value of the tightening force, judging the tightening state of the tightening bolt according to the change directions of the tightening force and the temperature of the connection end of the current-carrying busbar includes: when the tightening force shows an upward trend compared with the steady-state value of the tightening force, judge whether the tightening force is less than or equal to the upper limit of the tightening force; when it is greater than the upper limit of the tightening force, issue a warning of exceeding the tightening force limit. When it is less than or equal to the upper limit of the tightening force, judge whether the temperature of the connection end of the current-carrying busbar is greater than the steady-state temperature value; when it is greater than the steady-state temperature value, judge that the tightening force is normal; when it is equal to or lower than the steady-state value, issue a warning of the tightening of the tightening bolt.

[0068] Specifically, when the tightening force is greater than the steady-state value of the tightening force, it is determined that the tightening force shows an upward trend; in addition, multiple tightening forces can also be continuously obtained, and when multiple tightening forces are all greater than the steady-state value of the tightening force, it is determined that the tightening force shows an upward trend. Through the judgment of multiple tightening forces, the accuracy of subsequent tightening state judgment can be improved. Among them, when the tightening force is less than the upper limit of the tightening force and greater than the steady-state value of the tightening force, if the temperature is also greater than the steady-state temperature value at this time, it means that the increase in the tightening force is due to the thermal expansion of the bolt and the connection end of the current-carrying busbar caused by the temperature increase; if the temperature is less than or equal to the steady-state temperature value, that is, the temperature and the tightening force change in the opposite direction, a warning is issued for the force conduction of the components adjacent to the connection busbar.

[0069] In one embodiment, as Figure 3As shown, when the tightening force changes compared with the steady-state value of the tightening force, the tightening state of the tightening bolt is judged according to the change directions of the tightening force and the temperature of the connection end of the current-carrying busbar, including: when the tightening force shows a downward trend compared with the steady-state value of the tightening force, judge whether the tightening force is greater than or equal to the lower limit of the tightening force; when it is less than the lower limit of the tightening force, issue a warning of out-of-limit tightening force. When it is greater than or equal to the lower limit of the tightening force, judge whether the temperature of the connection end of the current-carrying busbar is less than the steady-state temperature value; when it is greater than or equal to the steady-state temperature value, issue a warning of loosening of the tightening bolt; when it is lower than the steady-state value, judge that the tightening force is normal.

[0070] Specifically, when the tightening force is less than the steady-state value of the tightening force, it is determined that the tightening force shows a downward trend; in addition, multiple tightening forces can also be continuously obtained, and when multiple tightening forces are all less than the steady-state value of the tightening force, it is determined that the tightening force shows a downward trend. By judging multiple tightening forces, the accuracy of subsequent tightening state judgment can be improved. Among them, when the tightening force is greater than the lower limit of the tightening force and less than the steady-state value of the tightening force, if the temperature is also less than the steady-state temperature value at this time, it means that the decrease in the tightening force is due to the contraction of the bolt and the connection end of the current-carrying busbar caused by the temperature decrease; if the temperature is greater than the steady-state temperature value, that is, the temperature and the tightening force change in the opposite direction, a warning of bolt loosening is issued.

[0071] Although the exemplary embodiments and their advantages have been described in detail, those skilled in the art can make various changes, substitutions and modifications to these embodiments without departing from the spirit of the present invention and the protection scope defined by the appended claims, and such modifications and variations all fall within the scope defined by the appended claims. For other examples, those of ordinary skill in the art should easily understand that the order of process steps can be changed while maintaining the protection scope of the present invention.

[0072] In addition, the application scope of the present invention is not limited to the processes, mechanisms, manufacturing, material compositions, means, methods and steps of the specific embodiments described in the specification. From the disclosure of the present invention, those of ordinary skill in the art will easily understand that for the processes, mechanisms, manufacturing, material compositions, means, methods or steps that already exist or will be developed in the future, if they perform substantially the same functions or achieve substantially the same results as the corresponding embodiments described in the present invention, they can be applied in accordance with the present invention. Therefore, the appended claims of the present invention are intended to include these processes, mechanisms, manufacturing, material compositions, means, methods or steps within their protection scope.

Claims

1. A monitoring device for the connection state of the current-commutating valve's guiding busbar, characterized in that, The commutation valve includes a diversion busbar connection end, and the diversion busbar connection end is connected to components in the commutation valve through a plurality of fastening bolts. The monitoring device includes: A temperature sensor, arranged above the diversion busbar connection end, for monitoring the temperature of the diversion busbar connection end; A fastening force sensor, for monitoring the fastening force of the fastening bolts; A controller, connected to the temperature sensor and the fastening force sensor, and judging the fastening state of the fastening bolts according to the change directions of the temperature and the fastening force; Judging the fastening state of the fastening bolts according to the change directions of the temperature and the fastening force includes: When the fastening force shows an upward trend compared with the steady-state value of the fastening force, judging whether the fastening force is less than or equal to the upper limit of the fastening force; When it is greater than the upper limit of the fastening force, issuing a warning of over-limit fastening force; When it is less than or equal to the upper limit of the fastening force, judging whether the temperature of the diversion busbar connection end is greater than the steady-state temperature value; When it is greater than the steady-state temperature value, judging that the fastening force is normal; When it is equal to or lower than the steady-state value, issuing a warning of fastening of the fastening bolts; When the fastening force changes compared with the steady-state value of the fastening force, judging the fastening state of the fastening bolts according to the change directions of the fastening force and the temperature of the diversion busbar connection end, including: When the fastening force shows a downward trend compared with the steady-state value of the fastening force, judging whether the fastening force is greater than or equal to the lower limit of the fastening force; When it is less than the lower limit of the fastening force, issuing a warning of over-limit fastening force; When it is greater than or equal to the lower limit of the fastening force, judging whether the temperature of the diversion busbar connection end is lower than the steady-state temperature value; When it is greater than or equal to the steady-state temperature value, issuing a warning of loosening of the fastening bolts; When it is lower than the steady-state value, judging that the fastening force is normal.

2. The commutation valve current-carrying busbar connection state monitoring device according to claim 1, wherein, It further includes: A temperature difference energy harvesting module, for converting the heat energy generated by the current flowing through the diversion busbar connection end into electric energy to supply power to the temperature sensor and / or the fastening force sensor; And / or, a vibration energy harvesting module, for converting the vibration energy generated by the vibration of the diversion busbar connection end into electric energy to supply power to the temperature sensor and / or the fastening force sensor.

3. The monitoring device for the connection state of the current-commutating valve diversion busbar according to claim 2, wherein, It further includes: An energy storage module, connected to the temperature difference energy harvesting module and / or the vibration energy harvesting module, the temperature sensor, and the fastening force sensor, storing the electric energy converted by the temperature difference energy harvesting module and / or the vibration energy harvesting module, and supplying power to the temperature sensor and the fastening force sensor.

4. The commutation valve current-carrying busbar connection state monitoring device according to claim 3, characterized in that, It further includes: A temperature difference energy harvesting management module and / or a vibration energy harvesting management module, the controller includes a main control unit, The main control unit is connected to the temperature difference energy harvesting management module and / or the vibration energy harvesting management module, sending a first PWM signal to the temperature difference energy harvesting management module and a second PWM signal to the vibration energy harvesting management module; The temperature difference energy harvesting management module includes a first converter, and the first converter converts the electric energy converted by the temperature difference energy harvesting module according to the first PWM signal and then inputs it into the energy storage module; The vibration energy harvesting management module includes a second converter, and the second converter converts the electric energy converted by the vibration energy harvesting module according to the second PWM signal and then inputs it into the energy storage module.

5. The monitoring device for the connection state of the commutation valve diversion busbar according to claim 4, characterized in that The temperature difference energy harvesting management module further includes a first switch, the vibration energy harvesting management module further includes a second switch, the controller further includes a switch control unit and an energy storage evaluation unit, both the switch control unit and the energy storage evaluation unit are connected to the main control unit, and the switch control unit is connected to the first switch and the second switch. The energy storage evaluation unit is connected to the energy storage module to obtain the parameters of the energy storage module. When the parameters are higher than the upper limit value, an overvoltage signal is generated to the main control unit, and the main control unit generates a disconnection signal to the switch control unit according to the overvoltage signal. The switch control unit disconnects the first switch and the second switch according to the disconnection signal. When the parameters are lower than the lower limit value, an undervoltage signal is generated to the main control unit, and the main control unit controls the temperature sensor and the fastening force sensor to enter the sleep state according to the undervoltage signal.

6. The monitoring device for the connection state of the current-commutating valve's diversion busbar according to claim 5, wherein The switch control unit is connected to the temperature difference energy harvesting module and the vibration energy harvesting module. The switch control unit obtains the first voltage signal of the electric energy in the temperature difference energy harvesting module. When the first voltage signal is lower than the first threshold value, the first switch is disconnected. The switch control unit obtains the second voltage signal of the electric energy in the vibration energy harvesting module. When the second voltage signal is lower than the second threshold value, the second switch is disconnected.

7. A method for monitoring the connection state of the current-carrying busbar of a converter valve, characterized in that, The converter valve includes a diversion busbar connection end, and the diversion busbar connection end is connected to the components in the converter valve through a plurality of fastening bolts. The monitoring method includes: Obtaining the fastening force of the fastening bolts. Judging whether the fastening force has changed compared with the fastening force steady state value. When the fastening force changes compared with the fastening force steady state value, judging the fastening state of the fastening bolts according to the change directions of the fastening force and the temperature of the diversion busbar connection end. When the fastening force changes compared with the fastening force steady state value, judging the fastening state of the fastening bolts according to the change directions of the fastening force and the temperature of the diversion busbar connection end, including: When the fastening force shows an upward trend compared with the fastening force steady state value, judging whether the fastening force is less than or equal to the upper limit of the fastening force. When it is greater than the upper limit of the fastening force, a fastening force overlimit warning is issued. When it is less than or equal to the upper limit of the fastening force, judging whether the temperature of the diversion busbar connection end is greater than the temperature steady state value. When it is greater than the temperature steady state value, judging that the fastening force is normal. When it is equal to or lower than the steady state value, a fastening warning of the fastening bolts is issued. When the fastening force changes compared with the fastening force steady state value, judging the fastening state of the fastening bolts according to the change directions of the fastening force and the temperature of the diversion busbar connection end, including: When the fastening force shows a downward trend compared with the fastening force steady state value, judging whether the fastening force is greater than or equal to the lower limit of the fastening force. When it is less than the lower limit of the fastening force, a fastening force overlimit warning is issued. When it is greater than or equal to the lower limit of the fastening force, judging whether the temperature of the diversion busbar connection end is lower than the temperature steady state value. When it is greater than or equal to the temperature steady state value, a loosening warning of the fastening bolts is issued. When it is lower than the steady state value, judging that the fastening force is normal.

Images