Switching device of electrical system and diagnostic method thereof

Abstract

The invention relates to a switching device for electrical applications, comprising: one or more switching poles; and one or more static contacts and one or more moving contacts are arranged for each switch pole. The moving contact can reversibly move between a disengagement position and a connection position, and when the moving contact is in the disengagement position, the moving contact is separated from the static contact; at the connection position, the moving contact is connected with the static contact; and the actuating assembly is in operative connection with the moving contact and comprises an electromagnetic actuator. The switching device includes or is operatively coupled to a control unit for controlling a function of the switching device. The control unit is adapted to execute a diagnostic method to monitor operation of the switching device during a switching manipulation.

Description

Technical Field

[0001] This invention relates to a switching device for electrical systems, such as circuit breakers, contactors, disconnectors, etc. More specifically, this invention relates to an electromagnetic switching device, which is particularly suitable for installation in medium-voltage electrical systems. Background Technology

[0002] Electromagnetic switching devices are widely used in electrical systems, especially in power grids or switchgear operating at medium voltage.

[0003] These devices typically represent a significant improvement over most traditional mechanical switching devices. However, factors such as wear of electrical contacts, changes in the operating conditions of moving parts, and aging of electromagnetic actuators can significantly impact their performance. Therefore, monitoring their performance, especially during switching operations, is crucial for preventing malfunctions and planning timely maintenance interventions.

[0004] A traditional method for collecting diagnostic information about the operation of electromagnetic switching devices is to deploy multiple sensors to monitor the behavior of the most critical components of the switching electrodes. However, such sensor deployments typically lead to an increase in the overall size of the switching electrodes and higher manufacturing costs. Therefore, implementing these solutions at the industrial level can be difficult and costly.

[0005] EP3460822A1 discloses a newer diagnostic method for examining the operating status of electromagnetic switching devices. This diagnostic method uses a mathematical model of the electromagnetic actuator to reconstruct the travel waveform of the moving contact of the switching pole based on observations of the voltage and current waveforms applied to the electromagnetic actuator.

[0006] This solution offers significant advantages because it avoids the need to install dedicated sensors to monitor the behavior of the switching device. Furthermore, it allows for the collection of accurate diagnostic information regarding anomalies during switch operation. However, this diagnostic approach requires powerful computing resources in practical implementation. Therefore, execution at a local level (e.g., via a control unit mounted on the switching device) may be challenging.

[0007] There is an urgent need for innovative solutions in the existing technology that can overcome or mitigate the significant limitations and defects of currently available solutions. Summary of the Invention

[0008] The present invention aims to meet this need by providing a switching device for electrical applications according to claim 1 and related dependent claims.

[0009] According to the general definition, the switching device of the present invention includes:

[0010] One or more switching poles;

[0011] Each switch pole is equipped with one or more stationary contacts and one or more moving contacts. The moving contact can reversibly move between a disengaged position (where the moving contact is disconnected from the stationary contact) and a engaged position (where the moving contact is engaged with the stationary contact).

[0012] An actuation assembly, which is operatively coupled to a moving contact, and includes an electromagnetic actuator.

[0013] The switching device includes or is operatively coupled to a control unit for controlling its functions.

[0014] The control unit is adapted to perform diagnostic methods to monitor the operating status of the switching device during switching operations.

[0015] The diagnostic method includes the following steps:

[0016] - During the switching operation of the switching device, acquire a detection signal indicating one or more electrical quantities related to the operation of the switching device;

[0017] - Based on the detected signal, calculate a diagnostic waveform for each electrical quantity that indicates the actual behavior of the electrical quantity during the switching operation of the switching device;

[0018] - Select the timing parameters related to the switching operation of the switching device;

[0019] - Select the diagnostic waveform and observation time window to calculate the selected time parameters;

[0020] - Determine the timing of disturbances in the selected diagnostic waveform within the chosen observation time window; and

[0021] - Calculate the selected time parameters based on the determined disturbance time.

[0022] Preferably, the one or more electrical quantities include at least one of the following:

[0023] - The voltage fed into the electromagnetic actuator;

[0024] - The excitation current fed into the electromagnetic actuator.

[0025] According to certain embodiments of the present invention, the step of determining the disturbance time includes:

[0026] - Calculate the first test value of the time derivative of the selected diagnostic waveform within the selected observation time window;

[0027] - Compare the first test value with a predefined first threshold; and

[0028] -The moment when the first test value within the observation time window first exceeds the first threshold is determined as the disturbance moment.

[0029] According to other embodiments of the present invention, the step of determining the time of the disturbance includes:

[0030] - Within the selected observation time window, calculate a second test value indicating the difference between the selected diagnostic waveform and a reference waveform, which indicates the ideal profile of the electrical quantity;

[0031] - Compare the second test value with a predefined second threshold;

[0032] -The moment when the second test value first exceeds the second threshold within the observation time window is determined as the disturbance moment.

[0033] In a further aspect, the present invention provides a diagnostic method for monitoring the operation of a switching device according to claim 9 and related dependent claims. Attached Figure Description

[0034] Other features and advantages of the invention will become more apparent from the following detailed description of preferred embodiments, which are given by way of illustration only and shown in the accompanying drawings, and which are non-limiting examples, wherein:

[0035] Figure 1-2 The switching device of the present invention is illustrated schematically;

[0036] Figure 3 , Figure 3A , Figure 3B , Figure 4 , Figure 4A , Figure 4B , Figure 5 The actuation components in the switching device of the present invention are schematically illustrated according to possible variant embodiments;

[0037] Figure 6 The diagnostic method for checking the operating status of a switching device according to the present invention is illustrated schematically.

[0038] Figures 7 to 10 Different embodiments of the diagnostic method according to the present invention are illustrated schematically. Detailed Implementation

[0039] Referring to the accompanying drawings, the present invention relates to a switching device 1 for use in an electrical system (e.g., a power grid or switchgear).

[0040] Preferably, the switching device 1 is a circuit breaker. However, in principle, it can also be different types of switching devices, such as contactors, disconnectors, etc.

[0041] Switchgear 1 is particularly suitable for installation in medium-voltage electrical systems. However, in principle it can also be used in other types of electrical systems, such as low-voltage electrical systems.

[0042] In the context of this application, “low voltage” (LV) refers to an operating voltage below 2kV AC and 2.5kV DC, while “medium voltage” (MV) refers to a higher operating voltage of up to tens of kV, such as up to 72kV AC and 100kV DC.

[0043] The switching device 1 includes one or more switching poles, each switching pole including one or more moving contacts 11 and one or more stationary contacts 10.

[0044] When the switchgear is installed in the field, the electrical contacts 10, 11 of each switch pole are electrically connected to the corresponding conductor of the electrical system (e.g., phase line or neutral line, not shown).

[0045] Figure 1 , 2 The switching device 1 according to the present invention is shown schematically.

[0046] The moving contact 11 can be reversibly moved between a disengaged position A (in which they are disengaged from the corresponding stationary contact 10) and a engaged position B (in which they are engaged with the stationary contact).

[0047] When the moving contact 11 is in the disengaged position A, the switching device is in the open state. Figure 1 In this situation, current cannot flow through the switching electrode.

[0048] When the moving contact 11 is in the connected position B, the switching device is in the closed state. Figure 2 In this case, current can flow through the switching electrode.

[0049] The switching device 1 is configured to perform switching operations to electrically connect or disconnect different circuit parts of an electrical system, for example, for protection or operational purposes.

[0050] The switch operation can be a closing operation, during which the moving contact of the switch pole moves from the disconnected position A to the connected position B, or it can be an opening operation, during which the moving contact of the switch pole moves from the connected position B to the disconnected position A.

[0051] The switching device 1 includes an actuation component 3 for reversibly moving the moving contact 11 of the switching pole between the aforementioned connected position A and disconnected position B.

[0052] According to the present invention, the actuation component 3 includes an electromagnetic actuator 4.

[0053] refer to Figure 3 , Figure 3A , Figure 3B , Figure 4 , Figure 4A and Figure 4B The electromagnetic actuator 4 preferably includes a yoke having a fixed yoke member 41 and a movable yoke member 43, the movable yoke member 43 being mechanically connected to the moving contact 11 via a suitable kinematic chain (not shown).

[0054] The movable yoke member 43 can reversibly move between a first position (in which it is connected to the fixed yoke member 41) and a second position (in which it is disconnected from the fixed yoke member 41).

[0055] The first position of the movable yoke component 43 corresponds to the disengaged position A of the moving contact 11. Figure 1 The second position of the movable magnetic yoke member 43 corresponds to the connection position B of the moving contact 11. Figure 2 ).

[0056] The electromagnetic actuator 4 also includes an excitation device 42, which includes one or more excitation windings wound around the fixed magnetic yoke member 41.

[0057] The excitation device 42 can be fed with an excitation current I. When the excitation current flows through the excitation device, it generates a magnetic flux that flows along the magnetic path formed by the fixed yoke member 41 and the movable yoke member 43. Therefore, the movable yoke member 43 can be actuated by the magnetic force generated by its magnetic interaction with the fixed yoke member 41.

[0058] According to some embodiments of the present invention ( Figure 3 , Figure 3A , Figure 3B In addition to the electromagnetic actuator 4, the actuation assembly 3 also includes one or more opening springs 5 ​​that are operatively connected to the moving contact 11.

[0059] In these embodiments of the invention, the electromagnetic actuator 4 provides a (magnetic) actuating force to move the moving contact 11 from the disengaged position A to the engaged position B during the closing operation of the switching device. The opening spring 5 provides a (mechanical) actuating force to move the moving contact 11 from the engaged position B to the disengaged position A during the opening operation of the switching device.

[0060] Preferably, the opening spring 5 is mechanically connected to the movable magnetic yoke member 43 of the electromagnetic actuator. They are arranged to store elastic potential energy during the closing operation and release the stored elastic potential energy during the opening operation.

[0061] According to some variations ( Figure 3 and 5 The electromagnetic actuator 4 provides a magnetic force to hold the moving contact 11 in the connected position B when the switching device is in the closed state.

[0062] In this case, the excitation device 42 (which may include a single excitation winding) is fed with a first excitation current I during the closing operation. L (Starting current), while a lower second excitation current I is fed when the switching device is in the closed state. H (Maintaining current).

[0063] Due to the magnetic interaction with the fixed yoke member 41, the movable yoke member 43 is held in the first position connected to the fixed yoke member until the excitation device 42 is fed with a holding current I. H In fact, the holding current I H As the magnetic flux flows along the excitation device 42, it generates a magnetic flux that is oriented to provide a magnetic force that moves the movable yoke member 43 toward the aforementioned first position.

[0064] When performing a disconnect / open operation, the holding current I fed into the excitation assembly 42 is cut off. H The magnetic interaction between the movable yoke component 43 and the fixed yoke component 41 ceases. The movable yoke component 43 can freely detach from the fixed yoke component 41 under the actuating force provided by the opening spring 5, and the opening spring 5 can release its stored elastic potential energy.

[0065] According to other variations ( Figure 3A The actuation assembly includes a locking mechanism 9a, which is adapted to engage with a movable part included in or operatively connected to the electromagnetic actuator 4 when the switching device is in a closed / closed state, so as to hold the moving contact 11 in the connected position B.

[0066] Preferably, the locking mechanism 9a is adapted to mechanically interact with the movable yoke member 43 of the electromagnetic actuator. For this purpose, the locking mechanism 9a can be actuated by a dedicated actuator (e.g., an actuation coil).

[0067] Once the switching device completes the closing operation, the locking mechanism 9a engages the movable yoke member 43 and locks it in the first position connected to the fixed yoke member 41.

[0068] When the tripping operation is to be performed, the locking mechanism 9a is released. The movable magnetic yoke 43 can move freely away from the fixed magnetic yoke 41 under the actuating force provided by the tripping spring 5, and the tripping spring 5 can release the stored elastic potential energy.

[0069] As an alternative, the locking mechanism 9a can interact mechanically with a motion transmission component (not shown) that mechanically connects the movable yoke component 43 of the electromagnetic actuator to the moving contact 11.

[0070] According to further variations ( Figure 3BThe actuation assembly includes one or more permanent magnets 9b that are operatively coupled to the electromagnetic actuator 4 and adapted to provide magnetic force to hold the moving contact 11 in the coupled position B when the switching device is in the closed state.

[0071] The permanent magnet 9b is adapted to generate magnetic flux flowing along the magnetic circuit formed by the fixed yoke member 41 and the movable yoke member 43, and is oriented to provide actuation force to move the movable yoke member toward the aforementioned first position connected to the fixed yoke member 41.

[0072] When the closing operation is completed, the moving contact 11 can remain in the connected position even if the excitation device 42 of the electromagnetic actuator is no longer powered.

[0073] When the tripping operation is performed, the excitation device 42 (which may include a single excitation winding) is fed a small excitation current. The magnetic flux generated by this current is opposite in direction to the magnetic flux generated by the permanent magnet 9b and is stronger. The magnetic force generated by the permanent magnet 9b is thus canceled out, and the movable yoke member 43 can move freely away from the fixed yoke member 41 under the actuation force provided by the tripping spring 5. The tripping spring 5 can release the stored elastic potential energy.

[0074] According to some embodiments of the present invention ( Figure 4 , Figure 4A , Figure 4B The electromagnetic actuator 4 provides a magnetic force to orient the moving contact 11 from the disconnected position A to the connected position B during the closing operation of the switching device, and provides a magnetic force to orient the moving contact 11 from the connected position B to the disconnected position A during the opening operation of the switching device.

[0075] In this case, the excitation device 42 may advantageously include a closed excitation winding and an open excitation winding, which are fed with excitation currents in opposite directions during the closing and opening operations, respectively.

[0076] According to some variations ( Figure 4 and 5 When the switching device is in the closed state, the electromagnetic actuator 4 provides a magnetic force that orients the moving contact 11 to hold the connected position B.

[0077] The excitation device 42 is fed with a first starting current during the closing operation of the switching device, and with a lower holding current when the switching device is in the (closed) state.

[0078] The excitation device 42 is fed a second starting current opposite to the direction of the first starting current during the opening operation of the switching device, and is fed a lower second holding current opposite to the direction of the first holding current when the switching device is in the closing state.

[0079] According to other variations ( Figure 4A The actuation assembly 3 preferably includes one or more permanent magnets 9b, which are operatively coupled to the electromagnetic actuator 4 and adapted to provide an actuating force (magnetic type) oriented to hold the moving contact 11 in the coupled position B when the switching device is in the closed state and possibly the open state (as described above).

[0080] The actuation assembly 3 preferably also includes one or more permanent magnets 9b, which are operatively coupled to the electromagnetic actuator 4 and adapted to provide an actuating force (magnetic type) to hold the moving contact 11 in the open position A when the switching device is in the open state.

[0081] According to further variations ( Figure 4B The actuation assembly includes a locking mechanism 9a adapted to engage with a moving part included in or operatively connected to the electromagnetic actuator 4 to hold the moving contact 11 in the engaged position B and the possible disengaged position A when the switching device is in the closed state and possibly the open state.

[0082] Preferably, the locking mechanism 9a is adapted to mechanically interact with the movable yoke member 43 of the electromagnetic actuator. As described above, the locking mechanism 9a can be actuated by a dedicated actuator (e.g., an actuation coil).

[0083] Preferably, the switching device 1 further includes a drive unit 6, which is electrically connected to the electromagnetic actuator 4 and adapted to provide an excitation current I to the electromagnetic actuator.

[0084] Refer again Figure 1-2 The drive unit 6 preferably includes a power supply device 61 for drawing electrical energy required to operate the electromagnetic actuator 4.

[0085] The power supply device 61 may include a capacitor bank for storing electrical energy for operating the electromagnetic actuator 4, and a power supply circuit (e.g., a circuit equipped with a switching device), which is electrically connected to a power source and is capable of continuously charging the capacitor bank.

[0086] Preferably, the drive unit 6 includes a drive circuit 62 electrically connected to the electromagnetic actuator 4 (i.e., the excitation device 42) and the power supply device 61.

[0087] The drive circuit 62 is adapted to provide excitation current to the electromagnetic actuator when it receives a suitable control signal CS from an electronic device (e.g., the control unit of a switching device).

[0088] The drive circuit 62 may include one or more suitable switching circuits and other electronic circuits, which may be controlled by a suitable control unit.

[0089] Preferably, the switching device 1 further includes a first sensing device 8a for providing a first detection signal DS1 indicating the excitation current I of the electromagnetic actuator.

[0090] The first sensing device 8a may include, for example, one or more current sensors (e.g., current transformers, Hall sensors, shunt circuits, etc.) operatively connected to the excitation device 42 of the electromagnetic actuator.

[0091] Preferably, the switching device 1 further includes a second sensing device 8b for providing a second detection signal DS2 indicating the supply voltage V of the electromagnetic actuator 4. The second sensing device 8b may include, for example, one or more voltage sensors (e.g., capacitive sensors, shunt circuits, etc.), which are operatively connected to the excitation device 42 of the electromagnetic actuator.

[0092] Generally, the aforementioned actuation component 3, drive unit 6, and sensing devices 8a and 8b can be implemented using solutions known in the art. Therefore, for the sake of brevity, only the aspects of these components relevant to the present invention will be described here.

[0093] Switching device 1 includes a control unit 7 for controlling the operation of the switching device. Figure 1-2 ).

[0094] Preferably, the control unit 7 includes suitable digital processing devices (e.g., one or more microprocessors) adapted to execute software instructions to generate control / data signals for managing the lifespan of the switching device 1. In principle, the control unit 7 may also include analog electronic circuitry appropriately configured to perform requested functions.

[0095] The control unit 7 is operatively coupled to the drive unit 6 and configured to control the drive unit 6, such as the drive circuit 62, by providing a suitable control signal CS. Conveniently, the control unit 7 is also operatively coupled to the sensing devices 8a and 8b to receive the aforementioned detection data DS1 and DS2 from these sensing devices.

[0096] Preferably, the control unit 7 includes a regulator module 71 configured to control the drive unit 6 based on detection signals DS1 and DS2 provided by the sensing devices 8a and 8b.

[0097] The regulator module 71 may include, for example, a PID regulator.

[0098] Preferably, the switching circuit and sensing devices 8a and 8b of the drive unit 6 form a control loop configured to perform PWM regulation on the excitation current I fed into the electromagnetic actuator. Therefore, the electromagnetic actuator 4 can be powered in the manner described above during the operation of the switching device.

[0099] The regulator module 71 is preferably implemented digitally. In this case, the microcontroller of the control unit 7 can execute appropriate software instructions to achieve the functions required by the regulator module.

[0100] The control unit 7 can be a controller mounted on the switchgear itself. Alternatively, it can be a stand-alone device installed at the local level, such as a digital relay.

[0101] An important feature of the present invention is that the control unit 7 is configured to perform a diagnostic method 100 to monitor the operation of the switching device during switch operation.

[0102] The steps of diagnostic method 100 will now be described in detail ( Figure 6 ).

[0103] Diagnostic method 100 includes step 101: during switching operation of the switching device, acquiring a detection signal indicating one or more electrical quantities of the switching device.

[0104] Preferably, the above-mentioned one or more electrical quantities include at least one of the following parameters:

[0105] - The voltage V fed into the electromagnetic actuator 4; and

[0106] - The excitation current I fed into the electromagnetic actuator 4.

[0107] Preferably, the diagnostic signals acquired in this step of the diagnostic method 100 are detection signals DS1 and DS2 provided by the first and second sensing devices 8a and 8b.

[0108] It should be noted that these sensing devices are not specifically designed for performing this diagnostic method 100. As described above, these components are essentially arranged to implement a control loop for operating the electromagnetic actuator. However, the diagnostic method 100 of the present invention utilizes the detection information provided by these components to perform a monitoring purpose.

[0109] The diagnostic method 100 includes step 102: for each monitored electrical quantity V, I, calculating a diagnostic waveform C indicating the actual behavior of the electrical quantity during the switching operation of the switching device. A C B C C C D One or more diagnostic waveforms C A C B C C C D Convenient reconstruction based on the acquired detection signals DS1 and DS2.

[0110] Diagnostic method 100 includes step 103: selecting a time parameter to be calculated related to the switching operation of the switching device.

[0111] As an example, the time parameter could be the separation time Δt of the electrical contacts of the switching pole during the opening operation. O An anomaly in this timing parameter may indicate a potential problem in the actuation chain of the moving contact 11, namely a problem in the electromagnetic actuator 4 or the motion chain connecting the moving contact 11 to the electromagnetic actuator.

[0112] As another example, another time parameter could be the closing time Δt of the electrical contacts of the switching pole during the closing operation. C An anomaly in this time parameter may indicate severe wear of the electrical contacts.

[0113] Other time parameters can be selected as needed, for example, to reconstruct the travel waveform of the moving contact 11 during the switching operation of the switching device.

[0114] Diagnostic method 100 includes step 104: selecting a diagnostic waveform C to test the selected time parameter. A C B C C C D and observation time window T A T B T C T D .

[0115] In this stage of diagnostic method 100, the diagnostic waveform and observation time window that are most suitable for testing the selected time parameters are selected.

[0116] For example, if the selected time parameter is the closing time Δt of the electrical contact during the closing operation. C Then, a diagnostic waveform indicating the actual behavior of the excitation current I fed into the electromagnetic actuator 4 can be selected. The selected time window can be the time interval during which the selected diagnostic waveform exhibits a stable profile. Alternatively, the selected time window can start from the moment when the selected diagnostic waveform exceeds a predetermined value. Obviously, as will become clearer in the examples described below, different diagnostic waveforms and observation time windows can be selected to examine the same selected time parameter.

[0117] Diagnostic method 100 includes step 105: within the selected observation time window T A T B T C T D Internally determine the selected diagnostic waveform C A C B C C C D The disturbance time t C t O .

[0118] For clarity, the “disturbance moment” specified here should be understood as the moment when the selected diagnostic waveform shows a sudden change in its profile.

[0119] In the selected diagnostic waveform C A C B C C C D The disturbance time t is identified in the monitored electrical quantities. C t O This allows the inventors to determine when, during the switching operation of the switching device, the electrical contacts 10 and 11 of the switching poles actually change their operating state, transitioning from a connected state to a disconnected state, and vice versa. The inventors observed that the selected diagnostic waveform C... A C B C C C D The disturbance time t C t O The existence of the moving contact is closely related to the change in the operating state of the actuation component 4 connected to the moving contact 11, and thus relates to the actual motion law of the moving contact.

[0120] Then, the diagnostic method 100 includes step 106: based on the identified disturbance time t C t O Calculate the selected time parameter Δt C Δt O For example, based on the selected time parameter Δt at the time of the disturbance. C Δt O The initial time t0 of the monitored switch operation (which is obviously known) can be measured against the determined disturbance time t. C t O It is calculated based on the time difference between them.

[0121] According to certain embodiments of the present invention, the selected diagnostic waveform C A C B Disturbance time t C The identification steps are based on the calculation of the time derivative of the selected diagnostic waveform.

[0122] Preferably, the disturbance time t is determined. C Step 105 includes:

[0123] -Calculate the selected diagnostic waveform C A C B In the selected observation time window T A T B The first test value of the time derivative within ck A ,ck B ;

[0124] -Calculate the first test value ck A ,ck B With the predefined first threshold TH A TH B Compare;

[0125] -The disturbance time t C The first test value ck is determined to be within the selected observation time window. A ,ck B Exceeding the first threshold TH A TH B At that moment.

[0126] According to other embodiments of the present invention, the selected diagnostic waveform C C C D The disturbance time t C t O The identification step is based on the diagnostic waveform and a reference waveform R that indicates the ideal profile of the monitored electrical quantity. C R D Calculation of the difference between them.

[0127] Preferably, the disturbance time t is determined. C t O Step 105 includes:

[0128] -Calculation indicates the time window T during the selected observation period. C T D Selected diagnostic waveform C C C D With reference waveform R C R D The second test value ck is the difference between (the ideal profiles of the indicated electrical quantities V and I) and (the ideal profiles of these quantities). C ,ck D ;

[0129] -Calculate the second test value ck C ,ck D With the predefined second threshold TH C TH D Compare;

[0130] -The disturbance time t C t O The second test value ck is determined to be within the selected observation time window. C ,ck D Exceeding the second threshold TH C TH D At that moment.

[0131] Figure 7An example of a practical implementation of the diagnostic method 100 according to the present invention is shown.

[0132] In this case, the selected time parameter to be calculated is the closing time Δt of electrical contacts 10 and 11 during the closing operation of the switching device. C The switching device is equipped with according to Figures 3 to 4 The electromagnetic actuator of the embodiment.

[0133] Select the diagnostic waveform C that indicates the actual behavior of the excitation current I fed into the electromagnetic actuator 4 during the closing operation of the switching device. A The selected current waveform C A It is calculated based on the first detection signal DS1 provided by the first sensing device 8A.

[0134] Select an observation time window T A The selected current waveform C during this period A It exhibits a stable outline.

[0135] Determine the observation time window T A The selected current waveform C A The disturbance time t C For this purpose, the selected current waveform C is calculated. A In the selected observation time window T A The first test value of the time derivative within ck A Then calculate the first test value ck. A With the predefined first threshold TH A Compare them.

[0136] The disturbance time t C The closing time of the electrical contact is identified as the first test value ck. A Exceeding the predefined first threshold TH A At that moment.

[0137] The closing time Δt of electrical contacts 10 and 11 during the closing operation is calculated based on the following relationship. C :

[0138] Δt C =t C -t0

[0139] Where t C t0 is the determined disturbance time, and t0 is the initial time of the closing operation.

[0140] Figure 8 Another example of a practical implementation of the diagnostic method 100 according to the present invention is shown.

[0141] In this case, the selected time parameter to be calculated is also equipped with a [database / mechanism]. Figure 3 The closing time Δt of electrical contacts 10 and 11 during the closing operation of the switching device of the electromagnetic actuator in the embodiment C .

[0142] The diagnostic waveform C selects the actual behavior of the voltage V of the electromagnetic actuator 4 fed into the switching device. B The selected voltage waveform C B It is calculated based on the second detection signal DS2 provided by the second sensing device 8B. An observation time window T is selected. B The voltage waveform C selected during this period B It exhibits a stable outline.

[0143] Determine the observation time window T B The selected voltage waveform C B The disturbance time t C For this purpose, the indicator is calculated within the selected observation time window T. B The selected voltage waveform C B The first test value of the time derivative ck B Then, the calculated second test value ck B With the predefined first threshold TH B Compare them.

[0144] The disturbance time t C The closing time of the electrical contact is identified as the first test value ck. B Exceeding a predefined first threshold TH (modally) B At that moment.

[0145] The closing time Δt of electrical contacts 10 and 11 during the closing operation is calculated based on the following relationship. C :

[0146] Δt C =t C -t0

[0147] Where t C t0 is the determined disturbance time, and t0 is the initial time of the closing operation.

[0148] Figure 9 Another example of a practical implementation of the diagnostic method 100 according to the present invention is shown.

[0149] In this case, the selected time parameter to be calculated is equipped with according to Figure 4 The closing time Δt of electrical contacts 10 and 11 during the closing operation of the switching device of the electromagnetic actuator in the embodiment C .

[0150] Select a diagnostic waveform C that indicates the actual behavior of the current I fed into the electromagnetic actuator 4 during the closing operation of the switching device. C The selected current waveform C C It is calculated based on the first detection signal DS1 provided by the first sensing device 8A.

[0151] Select an observation time window T C The observation time window T C From the selected current waveform C D The time t* begins when the predetermined value I* is exceeded.

[0152] Determine the observation time window T C The selected current waveform C C The disturbance time t C For this purpose, the selected current waveform C is calculated. C With reference waveform R C The second test value ck of the difference between C The reference waveform R C This indicates the ideal profile of the current circulating in the electromagnetic actuator during the closing operation. Then, the calculated second test value ck... C With the predefined second threshold TH C Compare them.

[0153] The disturbance time t C The closing time of the electrical contact is identified as the second test value ck. C Exceeding the predefined first threshold TH C At that moment.

[0154] The closing time Δt of electrical contacts 10 and 11 during the closing operation is calculated based on the following relationship. C :

[0155] Δt C =t C -t0

[0156] Where t C t0 is the determined disturbance time, and t0 is the initial time of the closing operation.

[0157] Figure 10 Another example of a practical implementation of the diagnostic method 100 according to the present invention is shown.

[0158] In this case, the selected time parameter to be calculated is equipped with according to Figure 4 The opening time Δt of electrical contacts 10 and 11 during the opening operation of the switching device of the electromagnetic actuator in the embodiment O.

[0159] The diagnostic waveform C is used to determine the actual behavior of the current I fed into the electromagnetic actuator 4 during the opening operation of the switching device. D The selected current waveform C D It is calculated based on the first detection signal DS1 provided by the first sensing device 8A.

[0160] Select an observation time window T D The observation time window T D From the selected current waveform C D The time t* begins when the predetermined value I* is exceeded.

[0161] Determine the observation time window T D The selected current waveform C D The disturbance time t O For this purpose, the selected current waveform C is calculated. D With reference waveform R D The second test value ck of the difference between D The reference waveform R D This indicates the ideal profile of the current circulating in the electromagnetic actuator during the opening operation. Then, the calculated second test value ck... D With the predefined second threshold TH D Compare them.

[0162] The disturbance time t O The moment the electrical contact opens is identified as within the selected observation time window T. D The second internal test value ck D Exceeding the predefined second threshold TH D At that moment.

[0163] The disconnection time Δt of electrical contacts 10 and 11 during the opening operation is calculated based on the following relationship. O :

[0164] Δt O =t O -t0

[0165] Where t C t0 is the determined disturbance time, and t0 is the initial time of the tripping operation.

[0166] Preferably, the control unit 7 includes a monitoring module 72 configured to perform diagnostic method 100. The monitoring module 71 is preferably implemented digitally. In this case, the microcontroller of the control unit 7 can execute appropriate software instructions to implement the functions required by the monitoring module.

[0167] As can be clearly seen from the above, another aspect of the present invention relates to a diagnostic method 100 for monitoring the operating state of a switching device 1 during switching operations. Figure 6 ).

[0168] Diagnostic methods 100 include:

[0169] - Step 101: Acquire detection signals DS1 and DS2, which indicate one or more electrical quantities V and I related to the operation of the switching device during the switching operation of the switching device;

[0170] Step 102: Based on the detected signals, calculate a diagnostic waveform C for each electrical quantity V, I, indicating the actual behavior of the electrical quantities V, I during the switching operation of the switching device. A C B C C C D ;

[0171] Step 103: Select the time parameter Δt associated with the switching operation of the switching device to be calculated. C Δt O ;

[0172] Step 104: Select diagnostic waveform C A C B C C C D and observation time window T A T B T C T D To calculate the selected time parameter Δt C Δt O ;

[0173] Step 105: Determine the observation time window T within the selected observation time window. A T B T C T D Selected diagnostic waveform C A C B C C C D The disturbance time t C t O ;

[0174] - Step 106: Based on the determined disturbance time t C t O Calculate the selected time parameter Δt C Δt O .

[0175] According to certain embodiments of the present invention, the disturbance time t is determined. C Step 105 includes:

[0176] -Calculate the selected diagnostic waveform C A C B In the selected observation time window T A T B The first test value of the time derivative within ck A ,ck B ;

[0177] -Calculate the first test value ck A ,ck B With the predefined first threshold TH A TH B Compare;

[0178] -The disturbance time t C Determined to be within the selected observation time window T A T B First internal test value ck A ,ck B Exceeding the first threshold TH A TH B At that moment.

[0179] According to other embodiments of the present invention, the disturbance time t is determined. C Step 105 includes:

[0180] -Calculate the selected diagnostic waveform C C C D With the indication in the selected observation time window T C T D Reference waveform R of the ideal profile of the internally detected electrical quantities V and I C R D The second test value ck of the difference between C ,ck D ;

[0181] -Calculate the second test value ck C ,ck D With the predefined second threshold TH C TH D Compare;

[0182] -The disturbance time t C t O Determined to be within the selected observation time window T C T D The second internal test value ck C ,ck D Exceeding the second threshold THC TH D At that moment.

[0183] The switching device and control method of the present invention have significant advantages over the solutions of the prior art.

[0184] In the switching device of the present invention, detection information typically used to control the operation of the electromagnetic actuator is processed by simple mathematical operations to empirically reconstruct diagnostic information (calculated time parameters) about the actual performance of the switching device, especially during switching operation.

[0185] Unlike existing solutions, such as those described in EP3460822A1, this diagnostic information is empirically reconstructed without using a dedicated mathematical model describing the operation of the electromagnetic actuator. Therefore, such diagnostic information can be collected without requiring a dedicated sensing setup and powerful data processing resources.

[0186] Therefore, based on the collected diagnostic information, it is possible to determine whether there are any abnormalities in the electrical contacts, electromagnetic actuators, and the motion chain connecting the electromagnetic contacts and the electromagnetic actuators.

[0187] This allows for appropriate intervention or planned maintenance operations to prevent switchgear malfunctions or failures.

[0188] The switching device of the present invention is easy to manufacture at the industrial level and has a cost advantage compared with existing technology solutions.

Claims

1. A switching device (1) for an electrical system, characterized in that, The switching device includes: - One or more switching poles; - Each switch pole is equipped with one or more stationary contacts (10) and one or more moving contacts (11), wherein the moving contact is reversibly movable between a disengaged position (A) and a engaged position (B), wherein in the disengaged position (A) the moving contact is disengaged from the stationary contact and in the engaged position (B) the moving contact is engaged with the stationary contact. -Actuation assembly (3), which is operatively connected to the moving contact (11) and includes an electromagnetic actuator (4); The switching device includes a control unit (7) or is operatively connected to the control unit (7). The control unit is adapted to perform a diagnostic method (100) to monitor the operation of the switching device during switch operation. The diagnostic method (100) is characterized by comprising the following steps: - Acquire (101) detection signals (DS1, DS2) indicating one or more electrical quantities (V, I) related to the operation of the switching device during the switching operation of the switching device; -Based on the detected signals, a diagnostic waveform (C) is calculated (102) for each electrical quantity, indicating the actual behavior of the electrical quantity (V,I) during the switching operation of the switching device. A C B C C C D ); - Select (103) the time parameter (Δt) associated with the switching operation of the switching device to be calculated. C ,Δt O ); - Select (104) diagnostic waveform (C) A C B C C C D ) and observation time window (T A ,T B ,T C ,T D ) to calculate the selected time parameter (Δt) C ,Δt O ); - Determine (105) within the selected observation time window (T) A ,T B ,T C ,T D The selected diagnostic waveform (C) within A C B C C C D The perturbation time (t) in ) C ,t O ); -Based on the determined disturbance time (t) C ,t O ) Calculate the selected time parameter (Δt) for (106) C ,Δt O ).

2. The switching device according to claim 1, characterized in that, Determine the disturbance time (t) C Step (105) includes: The calculation indicates the time window (T) of the selected observation time. A ,T B The diagnostic waveform selected within (C) A C B The first test value of the time derivative (ck) A ,ck B ); The first test value (ck) A ,ck B ) and the predefined first threshold (TH) A ,TH B ) for comparison; The disturbance time (t) C ) is determined to be within the selected observation time window (T) A ,T B The first test value (ck) within ) A ,ck B ) exceeds the first threshold (TH) A ,TH B (The moment).

3. The switching device according to any one of the preceding claims, characterized in that, The disturbance time (t) C ,t O Identify in the following ways: The calculation indicates the selected diagnostic waveform (C) C C D ) and reference waveform (R) C R D The second test value (ck) of the difference between ) C ,ck D The reference waveform (R) C R D ) indicates the selected observation time window (T C ,T D The ideal profile of the electrical quantities (V,I) described in the text; The second test value (ck) C ,ck D ) and the predefined second threshold (TH) C ,TH D ) for comparison; The disturbance time (t) C ,t O ) is determined to be within the selected observation time window (T) C ,T D The second test value (ck) within ) C ,ck D ) exceeds the second threshold (TH) C ,TH D (The moment).

4. The switching device according to any one of the preceding claims, characterized in that, The one or more electrical quantities include at least one of the following: The voltage (V) fed into the electromagnetic actuator (4); and Excitation current (I) fed into the electromagnetic actuator (4).

5. The switching device according to any one of claims 1 to 4, characterized in that, The actuation assembly (3) includes one or more opening springs (5) operatively coupled to the moving contact (11), wherein the electromagnetic actuator (4) is adapted to provide an actuating force oriented to move the moving contact (11) from the disengaged position (A) to the engaged position (B) during the closing operation of the switching device, wherein the opening springs (5) are adapted to provide an actuating force oriented to move the moving contact (11) from the engaged position (B) to the disengaged position (A) during the opening operation of the switching device.

6. The switching device according to any one of claims 1 to 4, characterized in that, The electromagnetic actuator (4) is adapted to provide an actuating force oriented to move the moving contact (11) from the disconnected position (A) to the connected position (B) during the closing operation of the switching device, and to provide an actuating force oriented to move the moving contact (11) from the connected position (B) to the disconnected position (A) during the opening operation of the switching device.

7. The switching device according to any one of the preceding claims, characterized in that, The switching device includes a drive unit (6) electrically connected to the electromagnetic actuator (4), the drive unit being adapted to supply an excitation current (If) to the electromagnetic actuator. L ,I H To operate the electromagnetic actuator.

8. The switching device according to any one of the preceding claims, characterized in that, The switching device is a medium-voltage switching device.

9. A diagnostic method (100) for monitoring the operation of a switching device (1) during switching operation, characterized in that, The switching device includes: - One or more switching poles; - Each switch pole is equipped with one or more stationary contacts (10) and one or more moving contacts (11), wherein the moving contact is reversibly movable between a disengaged position (A) and a engaged position (B), wherein in the disengaged position (A) the moving contact is disengaged from the stationary contact, and in the engaged position (B) the moving contact is engaged with the stationary contact. -Actuation assembly (3), which is operatively connected to the moving contact (11) and includes an electromagnetic actuator (4); The diagnostic method (100) is characterized by comprising the following steps: - Acquire (101) detection signals (DS1, DS2) indicating one or more electrical quantities (V, I) related to the operation of the switching device during the switching operation of the switching device; -Based on the detected signal, a diagnostic waveform (C) indicating the actual behavior of the electrical quantity (V,I) during the switching operation of the switching device is calculated (102) for each electrical quantity. A C B C C C D ); - Select (103) the time parameter (Δt) associated with the switching operation of the switching device to be calculated. C ,Δt O ); - Select (104) diagnostic waveform (C) A C B C C C D ) and observation time window (T A ,T B ,T C ,T D ) to calculate the selected time parameter (Δt) C ,Δt O ); - Determine (105) within the selected observation time window (T) A ,T B ,T C ,T D The selected diagnostic waveform (C) within A C B C C C D The perturbation time (t) in ) C ,t O ); Based on the determined disturbance time (t) C ,t O ) Calculate the selected time parameter (Δt) for (106) C ,Δt O ).

10. The diagnostic method according to claim 9, characterized in that, Determine the disturbance time (t) C Step (105) includes: The calculation indicates the time window (T) of the selected observation time. A ,T B The diagnostic waveform selected within (C) A C B The first test value of the time derivative (ck) A ,ck B ); The first test value (ck) A ,ck B ) and the predefined first threshold (TH) A ,TH B ) for comparison; The disturbance time (t) C ) is determined to be within the selected observation time window (T) A ,T B The first test value (ck) within ) A ,ck B ) exceeds the first threshold (TH) A ,TH B (The moment).

11. The diagnostic method according to claim 9 or 10, characterized in that, The disturbance time (t) C ,t O Identify in the following ways: Calculation indicates the selected diagnostic waveform (C) C C D ) and reference waveform (R) C R D The second test value (ck) of the difference between ) C ,ck D The reference waveform (R) C R D ) indicates the selected observation time window (T C ,T D The ideal profile of the electrical quantities (V,I) described in the text; The second test value (ck) C ,ck D ) and the predefined second threshold (TH) C, TH D ) for comparison; The disturbance time (t) C ,t O ) is determined to be within the selected observation time window (T) C ,T D The second test value (ck) within ) C ,ck D ) exceeds the second threshold (TH) C ,TH D (The moment).

12. The diagnostic method according to any one of claims 9 to 11, characterized in that, The one or more electrical quantities include at least one of the following: The voltage (V) fed into the electromagnetic actuator (4); and Excitation current (I) fed into the electromagnetic actuator (4).

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