A high-voltage disconnector

Abstract

The application provides a high-voltage isolating switch applied to the technical field of isolating switches, which continuously monitors the level of a position sensor and the current of a driving motor, records a first triggering moment, applies a preset compression current after the first triggering moment, and judges whether the level of the position sensor and the current of the driving motor meet preset first and second check conditions during the continuous action of the compression current, so that when the first and second check conditions are both met, it is determined that a conductive arm reaches a physical steady compression state, otherwise, the driving motor is controlled to stop running, and an abnormality is reported. The scheme solves the problems of virtual connection and rebound that may occur in the closing process of the traditional high-voltage isolating switch, has the advantages of ensuring reliable physical steady compression of the contact, and improving the reliability and safety of operation.

Description

Technical Field

[0001] This application relates to the field of disconnecting switch technology, and in particular to a high-voltage disconnecting switch. Background Technology

[0002] High-voltage disconnect switches are critical equipment in power systems, and the reliability of their closing and opening operations plays a vital role in the safe and stable operation of the power grid. During the design phase, in order to ensure that the equipment can still operate reliably under extreme conditions (such as contact surface icing, dirt deposition, or localized corrosion), a large torque margin is usually reserved for the drive motor and transmission mechanism.

[0003] In traditional high-voltage disconnector control strategies, the conductive arm is connected to the operating mechanism via a mechanical linkage, with its end engaging with the stationary contact to form the main current path. The pressure between the contacts is maintained by contact springs. Position detection primarily relies on mechanical position sensors or limit switches installed near the contact mechanism. These sensors generate a switching signal at the moment the contacts engage, and the control unit uses the rising edge of this signal as the criterion for complete closing. The control unit internally employs drive logic based on fixed timing and edge triggering. After receiving a closing command, the drive motor is energized according to a predetermined voltage and time period. Upon detecting the rising edge signal from the position sensor, the drive power is immediately cut off, and the system switches to a holding or de-energized state. This control method lacks secondary confirmation logic based on continuous contact time or contact pressure.

[0004] Under long-term outdoor operation conditions, the mechanical components of high-voltage disconnect switches will gradually wear down. The clearance between the transmission linkage and gears increases, and transmission friction and viscous resistance decrease; the stiffness of the contact springs decreases due to stress relaxation and fatigue effects. These degradations cause the mechanical energy required for the actual operation of the switch mechanism to be significantly lower than the factory-preset drive energy. However, the control unit's drive strategy still maintains high power output as set by the factory. At the beginning of the closing action, the drive motor accelerates rapidly with relatively low resistance, and the conductive arm accumulates more kinetic energy than expected within a short stroke, resulting in an end speed higher than the design speed under new conditions.

[0005] When the conductive arm collidees at high speed with the limiting block or contact body of the stationary contact, a huge impact force is generated, causing elastic deformation of the transmission link and conductive arm materials. The peak impact force is much higher than the peak force during normal contact. Some of the mechanical energy is converted into elastic potential energy and subsequently released, resulting in elastic rebound after the impact. The conductive arm retracts several millimeters from the fully engaged position. Although the compression of the contact structure triggers the position sensor, the existing position sensor has a short response time and the control logic uses an instantaneous response strategy on the rising edge. The control unit immediately interrupts the drive power supply after capturing the rising edge, and cannot continue to provide the driving force to maintain contact. After the elastic release, the contact fails to remain at the designed compression stroke, the contact spring is not compressed to the rated stroke, the contact pressure is lower than the specified value, and a high contact resistance, resulting in a poor connection.

[0006] This incomplete connection poses a serious potential hazard. The travel sensor in the remote monitoring system interprets transient compression as a complete closing, and uploads the closing status to the SCADA system. Dispatch and protection devices may restore power or continue applying load to the line based on this erroneous feedback. Once load current passes through the high-impedance contact point, the contact resistance causes localized heating and arcing. This heating further exacerbates oxidation and erosion of the contact surface, and may even lead to localized melting or welding of the contact point, causing the initial low contact pressure to evolve into a larger-scale fault. Such faults do not manifest instantaneously but gradually worsen over load cycles lasting from hours to days. The initial closing status reported by remote monitoring does not correspond to a safe metal-to-metal contact in terms of actual electrical contact, severely impacting the operational reliability of the high-voltage disconnector and the safety of the power grid.

[0007] To address the aforementioned issues, existing technologies urgently need improvement. Summary of the Invention

[0008] In view of the shortcomings of the prior art, this application provides a high-voltage disconnecting switch, which solves the problems of incomplete connection and rebound that may occur in the closing process of traditional high-voltage disconnecting switches, and ensures reliable physical steady-state clamping of the contacts, thus improving the reliability and safety of operation.

[0009] In a first aspect, a high-voltage disconnect switch includes a conductive arm, a drive motor, and a position sensor. The drive motor is used to drive the conductive arm to swing, so as to realize the closing or opening of the conductive arm. The position sensor is disposed at the end of the conductive arm and is used to generate a switch signal at the moment the conductive arm closes. The switch also includes a control unit.

[0010] The control unit is used to continuously monitor the level of the position sensor and the current of the drive motor during the swing of the conductive arm, and to record the initial triggering time when the level of the position sensor first changes from low to high.

[0011] After the initial triggering moment, a preset clamping current is applied to the drive motor. During the continuous action of the clamping current, it is determined whether the level of the position sensor and the current of the drive motor meet the preset first verification condition and second verification condition.

[0012] When both the first and second verification conditions are met, it is determined that the conductive arm has reached a physically steady-state compression state; otherwise, the drive motor is controlled to stop running and an abnormality is reported.

[0013] Furthermore, in the control unit, the first verification condition is whether the level of the position sensor remains high for the minimum clamping holding time; the second verification condition is whether the current of the drive motor exceeds a preset stall current threshold and remains high for a preset duration.

[0014] Furthermore, it also includes a timer connected to the control unit, and the control unit is further configured to start the timer to perform timing when the level of the position sensor meets the first verification condition;

[0015] During the timing process, if the level of the position sensor is detected to change from high to low, it is determined that the conductive arm has mechanically rebounded, and the timer is reset to zero.

[0016] Maintain the power output of the drive motor. When the level of the position sensor meets the first verification condition again, restart the timer to start timing until the timing duration reaches the preset duration.

[0017] Furthermore, it also includes a protection timer, which is connected to the control unit;

[0018] The protection timer is used to activate during the continuous application of the clamping current;

[0019] The control unit is also configured to determine that the closing of the conductive arm is abnormal when the duration of the protection timer exceeds the preset maximum allowable closing time, and the level of the position sensor does not meet the first verification condition or the current of the drive motor does not meet the second verification condition, and control the drive motor to stop running, while reporting the abnormality.

[0020] Furthermore, the control unit includes at least an information transmission subunit;

[0021] The information sending subunit is used to temporarily delay sending the closing signal when the level of the position sensor meets the first verification condition, and to generate and send the closing signal when the conductive arm reaches a physically steady-state pressing state. The closing signal includes a timestamp information confirming the closing and judgment basis information. The judgment basis information includes at least a first duration data of the position sensor level meeting the first verification condition and a second duration data of the current of the drive motor meeting the second verification condition.

[0022] Furthermore, the control unit also includes a control electronics disconnection unit and a power-off readback subunit;

[0023] The control disconnection unit is used to control the drive motor to continue to maintain power output for a preset buffer time when it is determined that the conductive arm has reached a physically steady state of compression, and to disconnect the power supply of the drive motor after the buffer time has ended;

[0024] The power-off readback subunit is used to continuously monitor the level of the position sensor from high level to low level within a preset readback time after the control disconnection unit cuts off the power to the drive motor, generate a potential loose connection alarm signal, and send the potential loose connection alarm signal to the information sending subunit.

[0025] Furthermore, the control unit also includes a thermal protection subunit, which is used to acquire the current of the drive motor in real time during the continuous operation of the clamping current;

[0026] The heat accumulation estimate is calculated based on the product of the square of the current and the energized running time of the drive motor;

[0027] The system compares the estimated heat accumulation value with the preset heat capacity limit threshold in real time, and when the estimated heat accumulation value reaches the heat capacity limit threshold, it controls the drive motor to stop power output and generates an overheating risk alarm signal.

[0028] Furthermore, the control unit also includes a real-time monitoring subunit; the real-time monitoring subunit is used to sample the current of the position sensor and the drive motor respectively according to a preset sampling period during the continuous operation of the clamping current;

[0029] The number of sampling points that continuously satisfy both the first and second verification conditions is counted. When the number of sampling points reaches the cumulative preset number of samples, it is determined that the level of the position sensor satisfies the first verification condition, and the current of the drive motor satisfies the second verification condition.

[0030] Furthermore, it also includes a moving contact and a stationary contact. The moving contact is disposed at the end of the conductive arm, and the stationary contact is disposed on the conductive base of the high-voltage disconnector. Under the drive of the drive motor, the moving contact moves from the open position to the closed position and comes into contact with the stationary contact, thereby realizing the closing.

[0031] Furthermore, the position sensor contacts the moving contact, and generates a corresponding electrical signal when the moving contact and the stationary contact come into mechanical compression.

[0032] Beneficial Effects: The high-voltage disconnecting switch proposed in this application continuously monitors the level of the position sensor and the current of the drive motor, records the initial triggering time, applies a preset clamping current after the initial triggering time, and during the continuous application of the clamping current, determines whether the level of the position sensor and the current of the drive motor meet the preset first and second verification conditions. If both the first and second verification conditions are met, it is determined that the conductive arm has reached a physically steady-state clamping state; otherwise, the drive motor is stopped and an anomaly is reported. This solution overcomes the limitations of traditional single position signals through multi-dimensional real-time status information and a dual verification mechanism, effectively eliminating the possibility of incomplete connection and rebound, ensuring that the contacts truly reach a physically steady-state clamping state, avoiding misjudgment due to instantaneous signals, and providing a fault handling mechanism. It solves the problems of incomplete connection and rebound that may occur in traditional high-voltage disconnecting switches during closing, and has the advantages of ensuring reliable physically steady-state clamping of the contacts, improving operational reliability and safety. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of a high-voltage disconnect switch proposed in this application.

[0034] Figure 2 This is an execution flowchart of the control unit of a high-voltage disconnector proposed in this application.

[0035] Labeling explanation: 1. Conductive arm; 2. Drive motor; 3. Displacement sensor. Detailed Implementation

[0036] The technical solutions of the embodiments of this application 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 this application, and not all of the embodiments. The components of the embodiments of this application described and marked in the accompanying drawings can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0037] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0038] Please refer to Figure 1 , Figure 2 This application provides a high-voltage disconnect switch, including a conductive arm 1, a drive motor 2, and a position sensor. The drive motor 2 drives the conductive arm 1 to swing, thereby closing or opening the conductive arm 1. The position sensor is located at the end of the conductive arm 1 and generates a switching signal at the moment the conductive arm 1 closes. The high-voltage disconnect switch also includes a control unit. The control unit continuously monitors the level of the position sensor and the current of the drive motor 2 during the swinging process of the conductive arm 1, and records the initial trigger moment when the level of the position sensor first changes from low to high. After the initial trigger moment, a preset clamping current is applied to the drive motor 2. During the continuous application of the clamping current, it is determined whether the level of the position sensor and the current of the drive motor 2 meet preset first and second verification conditions. When both the first and second verification conditions are met, it is determined that the conductive arm 1 has reached a physically steady-state clamping state; otherwise, the drive motor 2 is controlled to stop running, and an abnormality is reported.

[0039] Before elaborating on the working principle of this technical solution, the physical structure of the high-voltage disconnector switch is first described. The switch includes a moving contact and a stationary contact. The moving contact is located at the end of the conductive arm 1, while the stationary contact is fixedly mounted on the conductive base of the high-voltage disconnector switch. During the closing operation, the drive motor 2 drives the conductive arm 1 to swing from its open position to the closed position via a series of mechanical transmission mechanisms, such as a gearbox and connecting rods. In this position, the moving contact at the end of the conductive arm 1 abuts against the stationary contact on the conductive base, generating sufficient contact pressure to form a stable and reliable current path, thus achieving the closing function. A position sensor, such as a mechanical microswitch or a Hall effect sensor, is physically positioned in close relation to the moving contact. Specifically, the position sensor is arranged to directly or indirectly sense the physical contact state between the moving and stationary contacts. When the moving and stationary contacts abut and begin to generate mechanical compression (i.e., the contact spring is compressed), this mechanical deformation triggers the position sensor, causing it to generate a clear electrical signal, such as a jump from a low level to a high level.

[0040] In traditional control logic, once the control unit detects the instantaneous rising edge signal generated by the position sensor, it immediately determines that the circuit is closed and cuts off the power supply to the drive motor 2. However, after long-term service, due to wear of the transmission mechanism and fatigue of the contact springs, the mechanical damping and stiffness of the entire system will change. This can cause the conductive arm 1 to strike the stationary contact at excessive speed at the end of the closing phase. The huge impact kinetic energy causes elastic deformation of the mechanical structure, triggering the position sensor in a very short time. However, the stored elastic potential energy is then released, causing the conductive arm 1 to experience a slight mechanical rebound. Since the traditional control logic has already cut off the motor power supply at the moment of triggering, the motor cannot provide continuous pressure to suppress this rebound. Ultimately, this results in only a weak connection with insufficient contact pressure between the moving and stationary contacts, creating a potential hazard for subsequent electrical faults.

[0041] To address the aforementioned issues, the control unit introduced in this application employs a novel closed-loop control strategy based on multi-physical quantity verification. The core of the control unit can be a microcontroller unit (MCU) or a digital signal processor (DSP), which integrates data acquisition, logic judgment, and output control functions.

[0042] The working principle of the entire closing process is as follows: When the control unit receives the closing command from the outside, it first drives motor 2 to start, causing the conductive arm 1 to swing towards the closing position. During this process, the monitoring program inside the control unit starts running, continuously acquiring two key physical quantities at high frequency through its input ports, such as the analog-to-digital converter (ADC) channel: one is the output level signal of the position sensor, and the other is the current value in the working circuit of the drive motor 2.

[0043] When the moving contact at the end of conductive arm 1 first contacts the stationary contact and generates initial compression, the position sensor is triggered, and its output level jumps from a low level (e.g., 0 volts) representing the open state to a high level (e.g., 5 volts) representing the contact state. The control unit's monitoring program captures the rising edge of this level and accurately records this moment, defining it as the initial trigger moment.

[0044] Unlike existing technologies, the control unit does not consider this initial trigger moment as the end point of successful closing. Instead, it marks the beginning of a crucial verification phase. From the initial trigger moment, the control unit adjusts the power supply strategy to the drive motor 2, no longer simply maintaining operation, but applying a preset, specific clamping current to the drive motor 2. The amplitude of this clamping current is typically higher than the current when the motor is running under no-load or light-load conditions, but lower than the current when it is fully stalled. The purpose of applying this clamping current is to provide a continuous and strong mechanical thrust to overcome any possible elastic rebound and ensure that the contact spring is fully compressed, establishing the design-required contact pressure between the moving and stationary contacts.

[0045] Throughout the application of the clamping current, the control unit's verification logic operates in parallel. The verification logic needs to simultaneously determine whether two independent conditions are met: a first verification condition and a second verification condition. The first verification condition is related to the state of the position sensor, while the second verification condition is related to the load state of the drive motor 2, i.e., the current.

[0046] Only when both verification conditions are confirmed to be met during the application of the clamping current will the control unit ultimately determine that the conductive arm 1 has reached a truly physical steady-state clamping state. This state means that the moving and stationary contacts have not only achieved physical contact, but also that the stability of the contact and the contact pressure have met electrical safety standards. If either condition is not met during this period, or if the preset judgment time limit is exceeded, the control unit will determine that the closing is abnormal. At this time, the control unit will immediately execute the preset fault handling procedure, such as immediately cutting off the power supply to the drive motor 2 to stop its operation, and reporting the specific abnormal information to the upper-level monitoring system through the communication interface.

[0047] In this way, the technical solution of this application upgrades the criterion for successful closing from a single, instantaneous position signal to a dual, time-sequential verification process based on position persistence and pressure stability. This effectively identifies and avoids the problem of loose connection caused by mechanical rebound, and significantly improves the reliability of high-voltage disconnecting switch operation.

[0048] Furthermore, in one specific embodiment, the first and second verification conditions described above are explicitly defined. In the control unit, the first verification condition is defined as whether the level of the position sensor remains high for a preset minimum clamping holding time. The second verification condition is defined as whether the current of the drive motor 2 exceeds a preset stall current threshold, and this exceeding state is maintained for a preset duration.

[0049] This definition has profound physical significance. For the first verification condition, setting a minimum clamping holding time aims to filter out false position signals caused by instantaneous impacts. Mechanical rebound typically occurs within tens to hundreds of milliseconds after the impact. Therefore, by requiring the high-level signal of the position sensor to remain stable for a period of time, such as 300 milliseconds, it can be confirmed as valid contact. If any high-to-low transition occurs during the timing period, it will be considered a rebound, causing the first verification condition to fail. This time-integration-based judgment method replaces simple edge triggering, greatly enhancing the ability to identify the stability of the position signal. The minimum clamping holding time refers to the shortest time the position sensor's level must remain high after closing, ensuring the stability of the contact and avoiding incomplete connections caused by mechanical rebound. The minimum clamping holding time can be simulated in a laboratory environment, mimicking the actual operating conditions of a high-voltage disconnector. By gradually increasing the closing speed and mechanical load, the stability of the level signal after contact is observed. The shortest time the level signal remains high under different operating conditions is recorded, ensuring no level transition occurs within this time. Repeat the experiment multiple times and take the average value as the minimum compression holding time.

[0050] The core of the second verification condition lies in indirectly assessing the contact pressure between the contacts by monitoring the motor current. When the moving and stationary contacts are fully compressed and the mechanical transmission mechanism reaches the end of its stroke, the drive motor 2 will experience a huge reaction force, approaching a stalled state. In this state, the armature current of the motor will rise sharply. Therefore, a stall current threshold can be preset, which is significantly higher than the current during normal motor operation, for example, three times the normal operating current. When the control unit detects that the motor current exceeds this threshold, it can indirectly infer that the contacts have provided sufficient mechanical resistance, i.e., contact pressure has been established. Similarly, to eliminate instantaneous current spikes, this condition also requires that the current exceeding the threshold must be maintained for a preset duration, such as 150 milliseconds. This ensures that the high-load state is stable and continuous, directly corresponding to the physical state of the contact spring being fully compressed.

[0051] By combining these two specific and quantifiable verification conditions, the control unit can cross-verify the closing status from two dimensions: the continuity of position and the continuity of pressure. This creates a highly reliable judgment system that ensures the final confirmed closing status is truly stable and safe.

[0052] To more effectively address mechanical rebound, in some embodiments, the high-voltage disconnect switch also includes a timer connected to the control unit. The control unit is further configured to start the timer when the level of the position sensor meets a first verification condition, such as when it first goes high and begins to attempt to maintain that level.

[0053] During the timing process, the control unit continuously monitors the level of the position sensor. If the level suddenly jumps from high to low, the control unit immediately determines that the conductive arm 1 has mechanically rebounded. At this time, the control unit performs two key actions: first, it immediately resets the current count value of the timer to zero; second, and most importantly, it maintains the power output of the drive motor 2, that is, it continues to apply the clamping current.

[0054] Maintaining motor power output is key to overcoming springback. Sustained thrust causes the springbacked conductive arm 1 to move forward again, re-engaging with the stationary contact. When the moving and stationary contacts re-engage and compress, the position sensor's voltage level rises from low to high again. Once the control unit detects this new rising edge and confirms that the voltage level meets the first verification condition again, it restarts the timer, beginning a new counting cycle from zero.

[0055] This process repeats until the timer's accumulated duration successfully reaches the preset duration, such as the aforementioned minimum clamping time, without being reset midway. Only then is the first verification condition truly satisfied. This closed-loop control logic with springback detection and automatic compensation enables the system to proactively counteract and correct mechanical instability, ensuring that even in the event of springback, a stable clamping state can ultimately be achieved and maintained.

[0056] To ensure the safety of the entire closing process and prevent the motor from running under overload for an extended period due to unexpected mechanical jamming or sensor failure, in some embodiments, the high-voltage disconnect switch also includes a protection timer, which is also connected to the control unit.

[0057] The function of this protection timer is to set a maximum allowable time limit for the entire clamping verification phase. Specifically, the protection timer starts synchronously the moment the control unit begins to apply clamping current to drive motor 2.

[0058] While performing the first and second verification condition checks, the control unit also monitors the duration of the protection timer. If the protection timer exceeds a preset maximum allowable closing time, such as five seconds, and the position sensor level still does not meet the first verification condition, or the current of drive motor 2 still does not meet the second verification condition, the control unit will determine that a serious closing abnormality has occurred in conductive arm 1. This abnormality may stem from the transmission mechanism being jammed by a foreign object, preventing conductive arm 1 from reaching its final position, or from a severe decrease in motor drive torque, failing to provide sufficient clamping force. In this situation, continuing to run the motor is not only ineffective but may also lead to motor overheating and burnout or damage to mechanical components. Therefore, once this timeout protection mechanism is triggered, the control unit will immediately cut off the power supply to drive motor 2 and report a clear abnormal code indicating timeout failure to the monitoring center.

[0059] In a preferred embodiment, in order to improve the quality of information interaction with the upper-level monitoring system and avoid it from making misjudgments based on incorrect intermediate states, the control unit includes at least one information sending subunit.

[0060] The logic of this information transmission subunit is specially designed. During the closing process, when the position sensor's level first meets the first verification condition, for example, when the level just goes high, the information transmission subunit will temporarily delay sending the traditional closing-in signal. This is to avoid misreporting the initial, potentially unstable contact state as the final successful state.

[0061] The information sending subunit will wait until the main logic of the control unit completes all verifications and finally determines that the conductive arm 1 has reached a physically steady-state compression state. Only at this moment will the information sending subunit generate and send out a confirmation closing signal. Furthermore, the content of this closing signal has been greatly enriched. The signal not only contains precise timestamp information confirming the closing is complete for accurate tracing of the event sequence, but also contains a set of judgment criteria information. This set of judgment criteria information includes at least two key data: one is the first duration data of the position sensor level meeting the first verification condition, i.e., how long the high level was actually maintained; the other is the second duration data of the current of the drive motor 2 meeting the second verification condition, i.e., how long the high current was actually maintained.

[0062] By sending such a closing signal with detailed evidence, the remote dispatching and protection system can not only know that the switch has closed, but also understand the quality and reliability of this closing. For example, it can assess the stability of the contact based on the duration data, providing valuable data support for predictive maintenance of the equipment.

[0063] To achieve the highest level of reliability verification, in some embodiments, the control unit also includes a control electronics disconnection unit and a power-off readback subunit to perform final confirmation of the closing status after the motor is powered off.

[0064] The specific workflow is as follows: When the control unit determines that the conductive arm 1 has reached a physically steady-state compression state, the control disconnection unit will not immediately cut off the power to the drive motor 2. Instead, it will control the drive motor 2 to continue to maintain power output for a preset buffer period, such as 500 milliseconds. The purpose of setting this buffer period is to allow the residual stress in the entire mechanical transmission chain to be fully released and redistributed, so that the system can achieve a more thorough mechanical balance under the condition of power maintenance.

[0065] After the buffer period ends, the power-off control unit will execute the command to cut off the power supply to drive motor 2. From the moment the motor power is cut off, the power-off readback subunit begins to work. Within a preset readback period, such as one second, the power-off readback subunit will continuously and accurately monitor the level of the position sensor.

[0066] If the position sensor's voltage level jumps from high to low when the motor is completely de-energized and there is no external force maintaining it, this is a very clear danger signal. This indicates that the previous stable state was maintained by the continuous thrust of the motor; once the external force is removed, the locking force or spring pressure of the mechanical system itself is insufficient to maintain stable contact, resulting in delayed rebound. The power-off readback subunit will immediately generate a potential loose connection alarm signal and send it out through the information transmission subunit. This alarm signal is of a very high level, usually indicating a serious defect in the mechanical parts of the disconnector switch, requiring immediate repair.

[0067] During the continuous application of the clamping current, the drive motor 2 is under high load or even near-stall state for an extended period, generating a large amount of heat. If left uncontrolled, this could lead to insulation damage or permanent demagnetization of the motor. Therefore, in some embodiments, the control unit also integrates a thermal protection subunit.

[0068] The function of the thermal protection subunit is to perform real-time estimation and protection of the thermal state of the drive motor 2 during the application of the clamping current. Its operation involves acquiring the current value of the drive motor 2 in real time. The algorithm inside the control unit calculates a thermal accumulation estimate based on the collected current value and the energizing time. A commonly used and effective physical model is based on the product of the square of the current and time, i.e., I² multiplied by t. In specific implementation, the control unit can sample the current at a fixed time interval, such as every ten milliseconds, and then accumulate the product of the square of the current value at that sampling point and the time interval into an internal register. The value of this register represents the thermal accumulation estimate of the motor.

[0069] Meanwhile, a thermal capacity limit threshold based on the motor model and heat dissipation conditions is pre-set in the non-volatile memory of the control unit. The thermal protection subunit compares the calculated heat accumulation estimate with this threshold in real time. Once the estimate reaches or exceeds the thermal capacity limit threshold, indicating that the motor temperature may be approaching its safe upper limit, the thermal protection subunit will immediately enforce a protective action, namely controlling drive motor 2 to stop power output to prevent overheating damage. At the same time, an overheating risk alarm signal will be generated to notify maintenance personnel that the motor was at risk of thermal overload.

[0070] In order to implement the verification logic more accurately and more resiliently in the digital control system, in some embodiments, the control unit also includes a real-time monitoring subunit.

[0071] This real-time monitoring subunit is responsible for converting continuous analog signals into discrete digital sequences and making judgments based on statistical methods. During the continuous application of the clamping current, the real-time monitoring subunit samples the voltage of the position sensor and the current of the drive motor 2 through an analog-to-digital converter according to a preset sampling period, such as once every millisecond, to obtain a series of discrete sampling point data.

[0072] The judgment logic has also changed from being based on analog time to being based on sampling point counting. For example, for the first verification condition, an external timer is no longer used; instead, the number of sampling points that continuously meet the high-level condition is counted. If the minimum clamping holding time is set to 300 milliseconds and the sampling period is 1 millisecond, then the first verification condition is only considered met when the voltage values ​​of 300 consecutive sampling points are all higher than the preset high-level threshold, as counted by the real-time monitoring subunit. Similarly, for the second verification condition, the number of sampling points that continuously meet the current greater than the stall current threshold also needs to be counted. Only when this number reaches the cumulative preset number of samples is the second verification condition considered met.

[0073] This method, based on digital sampling and sample quantity statistics, can effectively filter out high-frequency noise and transient glitches in the signal, making the judgment results more stable and reliable, and greatly improving the robustness of the control system.

[0074] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A high-voltage disconnect switch, comprising a conductive arm, a drive motor, and a position sensor, wherein the drive motor drives the conductive arm to perform a swinging motion to achieve closing or opening of the conductive arm, and the position sensor is disposed at the end of the conductive arm to generate a switching signal at the moment the conductive arm closes, characterized in that, It also includes a control unit; The control unit is used to continuously monitor the level of the position sensor and the current of the drive motor during the swing of the conductive arm, and to record the initial triggering time when the level of the position sensor first changes from low to high. After the initial triggering moment, a preset clamping current is applied to the drive motor. During the continuous action of the clamping current, it is determined whether the level of the position sensor and the current of the drive motor meet the preset first verification condition and second verification condition. In the control unit, the first verification condition is whether the level of the position sensor remains high for the minimum clamping holding time; the second verification condition is whether the current of the drive motor exceeds a preset stall current threshold and remains high for a preset duration. It also includes a timer connected to the control unit, and the control unit is further configured to start the timer to perform timing when the level of the position sensor meets the first verification condition; During the timing process, if the level of the position sensor is detected to change from high to low, it is determined that the conductive arm has mechanically rebounded, and the timer is reset to zero. Maintain the power output of the drive motor. When the level of the position sensor meets the first verification condition again, restart the timer to start timing until the timing duration of the timer reaches the preset duration. When both the first and second verification conditions are met, it is determined that the conductive arm has reached a physically steady-state compression state; otherwise, the drive motor is controlled to stop running and an abnormality is reported.

2. A high-voltage disconnector according to claim 1, characterized in that, It also includes a protection timer, which is connected to the control unit; The protection timer is used to activate during the continuous application of the clamping current; The control unit is also used to determine that the closing of the conductive arm is abnormal when the duration of the protection timer exceeds the preset maximum allowable closing time, and the level of the position sensor does not meet the first verification condition or the current of the drive motor does not meet the second verification condition, and to control the drive motor to stop running, while reporting the abnormality.

3. A high-voltage disconnect switch according to claim 1, characterized in that, The control unit includes at least an information transmission subunit; The information sending subunit is used to temporarily delay sending the closing signal when the level of the position sensor meets the first verification condition, and to generate and send the closing signal when the conductive arm reaches a physically steady-state pressing state. The closing signal includes a timestamp information confirming the closing and judgment basis information. The judgment basis information includes at least a first duration data of the position sensor level meeting the first verification condition and a second duration data of the current of the drive motor meeting the second verification condition.

4. A high-voltage disconnector according to claim 3, characterized in that, The control unit also includes a control electronics disconnection unit and a power-off readback subunit; The control disconnection unit is used to control the drive motor to continue to maintain power output for a preset buffer time when it is determined that the conductive arm has reached a physically steady state of compression, and to disconnect the power supply of the drive motor after the buffer time has ended; The power-off readback subunit is used to continuously monitor the level of the position sensor from high level to low level within a preset readback time after the control disconnection unit cuts off the power to the drive motor, generate a potential loose connection alarm signal, and send the potential loose connection alarm signal to the information sending subunit.

5. A high-voltage disconnect switch according to claim 1, characterized in that, The control unit also includes a thermal protection subunit, which is used to acquire the current of the drive motor in real time during the continuous operation of the clamping current. The heat accumulation estimate is calculated based on the product of the square of the current and the energized running time of the drive motor; The system compares the estimated heat accumulation value with the preset heat capacity limit threshold in real time, and when the estimated heat accumulation value reaches the heat capacity limit threshold, it controls the drive motor to stop power output and generates an overheating risk alarm signal.

6. A high-voltage disconnector according to claim 1, characterized in that, The control unit further includes a real-time monitoring subunit; the real-time monitoring subunit is used to sample the current of the position sensor and the drive motor respectively according to a preset sampling period during the continuous operation of the clamping current; The number of sampling points that continuously satisfy both the first and second verification conditions is counted. When the number of sampling points reaches the cumulative preset number of samples, it is determined that the level of the position sensor satisfies the first verification condition, and the current of the drive motor satisfies the second verification condition.

7. A high-voltage disconnector according to claim 1, characterized in that, It also includes a moving contact and a stationary contact. The moving contact is disposed at the end of the conductive arm, and the stationary contact is disposed on the conductive base of the high-voltage disconnector. Under the drive of the drive motor, the moving contact moves from the open position to the closed position and comes into contact with the stationary contact, thereby realizing the closing.

8. A high-voltage disconnector according to claim 7, characterized in that, The position sensor is in contact with the moving contact, and generates a corresponding electrical signal when the moving contact and the stationary contact come into mechanical compression.

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