Switching diagnostic device and associated switching device and diagnostic method

Abstract

A diagnostic device (20) for a switching device (10) comprises a switching member (35) configured to switch between a first position and a second position, a controller (80) and a tripping system (40) designed to command the switching when a first criterion or a second criterion is met, the first criterion being a first temperature greater than or equal to a temperature threshold, the second criterion being a magnetic field greater than or equal to a field threshold, the magnetic field being generated by a current circulating when the switching member (35) is in the first position. The diagnostic device (20) comprises a sensor (70) configured to estimate a second temperature value, the controller (80) being configured to diagnose the switching as due to the first criterion as a function of the second temperature value.

Description

Technical Field

[0001] This invention relates to a switching diagnostic device. It also relates to a switching device including such a diagnostic device and a diagnostic method implemented by such a diagnostic device. Background Technology

[0002] To prevent electrical faults, especially overcurrent, many devices use switching devices (or “circuit breakers”) that are configured to cut off circulating current when the current intensity is too high relative to a reference value, for example, to prevent the conductors that conduct current from overheating.

[0003] For this reason, the circuit breakers commonly used are of the so-called "thermal-magnetic" type. These circuit breakers use a switching system to open the switch and interrupt the current, which operates in two different and independent ways.

[0004] When the magnetic field generated by the current (which circulates entirely or partially in, for example, a coil) is greater than or equal to a threshold, the first part of the switching system commands the switch to disconnect. For example, when the magnetic field is greater than or equal to the threshold, the force exerted by that magnetic field on the movable element exceeds another force, for example, exerted by a spring, thus driving the displacement of the movable element to disconnect the switch. When the intensity is very high, these mechanisms allow for very rapid switching, especially in cases of very accidental and intense overcurrents, typically caused by short circuits.

[0005] When the temperature of the circuit breaker (caused by overload) is greater than or equal to another threshold, the second part commands the switching to disconnect. For example, the bimetallic strip in contact with the conductor through which the current circulates (or the bimetallic strip itself through which the current passes) deforms above a certain temperature to drive the switching to disconnect. These mechanisms are not inherently as fast as magnetic mechanisms, but allow for lower-intensity tripping to handle lower-intensity but longer-duration overloads.

[0006] In addition, circuit breaker switching systems typically include a handle to allow operators or users to manually disconnect or close the switch.

[0007] Therefore, there can be several different reasons for switching current by a circuit breaker, and these reasons are very different in nature. As a result, it is desirable to determine the cause of the switching in advance before intervening to restore the device operation and close the switch, especially since the precautions to be taken vary from situation to situation. Summary of the Invention

[0008] However, it is difficult to diagnose the cause of such switching remotely. For example, when the current is very high, the sensor measuring the current intensity may become saturated, making it impossible to accurately determine the maximum current value, especially if it has reached the threshold that would cause the switching system to trip. Furthermore, the operation of the bimetallic strip is well established under optimal and controlled conditions, but it can actually vary compared to its nominal operation. It is then necessary to establish a lookup table (or “derating table”) to correlate the actual conditions with the nominal conditions, thus taking into account the specific device conditions.

[0009] Therefore, there is a need for a switching diagnostic device for thermal-magnetic circuit breakers that is more reliable than existing diagnostic devices.

[0010] Therefore, a diagnostic device (20) for a switching device (10) is proposed. The switching device (10) includes a switching module (15), which includes an input (25), an output (30), a switching member (35), and a tripping system (40). The switching member (35) is configured to switch between a first position and a second position. In the first position, the switching member (35) is electrically connected to the input (25) and the output (30). In the second position, the switching member (35) electrically isolates the input (25) and the output (30). The tripping system (40) is designed to command the switching member (35) to switch from the first position to the second position. The tripping system (40) is a thermomagnetic tripping system and is configured to command switching when one of a first criterion or a second criterion is met. The first criterion is the fact that a first temperature of an element of the tripping system (40) is greater than or equal to a temperature threshold. The criterion is the fact that the magnetic field is greater than or equal to a field threshold, the magnetic field being generated by the current circulating between the input and output when the switching member (35) is in the first position, the diagnostic device (20) includes a controller (80) configured to detect the switching of the switching member (35) from the first position to the second position, the diagnostic device (20) is characterized in that it includes a temperature sensor (70) and a current sensor (75), the temperature sensor (70) being configured to estimate a value of a second temperature of the switching device (10), the current sensor (75) being configured to measure a value of the intensity of a current, and the controller (80) being configured to, after detecting a switching, diagnose the switching as a switching due to a first criterion based on at least one estimated second temperature value, when at least one intensity value is greater than or equal to a first current threshold, the first current threshold being a function of at least one of the estimated second temperature values.

[0011] According to an advantageous but non-mandatory embodiment, in the diagnostic device (20), the controller (80) includes a memory (100) and is configured to determine the first current threshold based on a table stored in the memory (100) containing a first current threshold based on a second temperature, or based on a function stored in the memory that relates the first current threshold to a second temperature value.

[0012] In the diagnostic device (20), the controller (80) is configured to estimate at least one intensity value based on at least one value of the derivative of the intensity measured by the current sensor, and is configured to diagnose a switch as a switch due to a first criterion based on at least one estimated intensity value.

[0013] In the diagnostic device (20), the controller (80) is configured to: detect saturation of the current sensor (75), estimate at least one intensity value from at least one value of the derivative of the measured intensity, and diagnose switching based at least on the estimated intensity value when saturation is detected, and directly diagnose switching based on at least one intensity value measured by the current sensor (75) when there is no saturation.

[0014] In the diagnostic device (20), the current is an alternating current exhibiting a time period, and each estimated intensity value is estimated based on the derivative of the intensity, which is the maximum derivative of the intensity over the time period of the current. Each intensity value is estimated by considering the intensity as a sine function of time.

[0015] In the diagnostic device (20), at least one second temperature value is the average value of the second temperature during the time band prior to the switch.

[0016] In the diagnostic device (20), the controller (80) is also configured to compare at least one intensity value of the current with a second current threshold, and is configured to diagnose a switching due to a second criterion when the intensity value is greater than or equal to the second current threshold.

[0017] In the diagnostic device (20), the tripping system (40) includes a component (50) configured to command a switch according to an operator’s command, and a controller (80) configured to diagnose a switch as a switch commanded by the operator if the controller does not diagnose the switch as a switch caused by a first criterion or a second criterion.

[0018] In the diagnostic device (20), the second temperature is the temperature of the diagnostic device (20).

[0019] In the diagnostic device (20), the second temperature is the temperature of the switching module (15).

[0020] A switching device (10) is also proposed, including a switching module (15), the switching module (15) including an input (25), an output (30), a switching member (35) and a tripping system (40), the switching member (35) being configured to switch between a first position and a second position, in the first position the switching member (35) being electrically connected to the input (25) and the output (30), and in the second position the switching member (35) being electrically isolated from the input (25) and the output (30), the tripping system (40) being designed to command the switching member (35) to switch from the first position to the second position, the tripping system (40) being a thermomagnetic tripping system being configured to command switching when one of a first criterion or a second criterion is met, the first criterion being the fact that a first temperature of an element of the tripping system (40) is greater than or equal to a temperature threshold, the second criterion being the fact that a magnetic field is greater than or equal to a field threshold, the magnetic field being generated by a current circulating between the input and the output when the switching member (35) is in the first position, the switching device (10) including a diagnostic device (20).

[0021] According to an advantageous but non-mandatory embodiment, in the switching device (10), the diagnostic device (20) includes a first housing (64) containing a controller (80), and the switching module (15) includes a second housing (22) containing a switching member (35) and a tripping system (40). The first housing (64) is different from the second housing (22) and is configured to be fixed to the second housing (22).

[0022] The switching device (10) includes a single main housing containing a diagnostic device (20) and a switching module (15).

[0023] A method for diagnosing the switching of a switching device (10) is also proposed. The switching device (10) includes a switching module (15), which includes an input (25), an output (30), a switching member (35), and a tripping system (40). The switching member (35) is configured to switch between a first position and a second position. In the first position, the switching member (35) is electrically connected to the input (25) and the output (30). In the second position, the switching member (35) electrically isolates the input (25) from the output (30). The tripping system (40) is designed to command the switching member (35) to switch from the first position to the second position. The tripping system (40) is a thermomagnetic tripping system and is configured to command switching when one of a first criterion or a second criterion is met. The first criterion is that a first temperature of an element of the tripping system (40) is greater than a certain value. The second criterion is the fact that the magnetic field is greater than or equal to the field threshold, which is generated by the current circulating between the input and output when the switching member (35) is in the first position. The method is implemented by a diagnostic device (20) including a controller (80), a current sensor (75) and a temperature sensor (70). The method includes the following steps: measuring (200) at least one value of the second temperature of the switching device by the temperature sensor (70); detecting the switching of the switching member (35) from the first position to the second position by the controller (80); and diagnosing (255) the switching as a switching due to the first criterion when at least one intensity value is greater than or equal to the first current threshold, based on at least one estimated second temperature value, the first current threshold being a function of at least one of the estimated second temperature values. Attached Figure Description

[0024] The features and advantages of the invention will become apparent from the following description, which is given entirely by way of non-limiting example and with reference to the accompanying drawings, wherein:

[0025] - Figure 1 It is a schematic diagram of a switching device including diagnostic equipment, and

[0026] - Figure 2 It is by Figure 1 A flowchart illustrating the steps of a diagnostic method implemented by a diagnostic device. Detailed Implementation

[0027] Figure 1 The switching device 10 is shown in the figure.

[0028] The switching device 10 includes a switching module 15 and a diagnostic device 20.

[0029] The switching device 10 will be described below with the case that the switching device 10 includes a single pole, but it will be apparent to those skilled in the art that the number of poles (i.e. the number of input-output pairs that the switching device 10 is designed to connect or disconnect) can vary.

[0030] The switching module 15 and the diagnostic device 20 are, for example, different devices from each other, and both form the switching device 10. Specifically, as described below, the switching module 15 and the diagnostic device 20 are each contained in different housings.

[0031] It should be noted that, according to a possible variation, the switching module 15 and the diagnostic device 20 are contained in the same housing, and the components constituting the switching module 15 are not separated from the components constituting the diagnostic device 20 by a wall, for example.

[0032] Switching module 15 itself is known.

[0033] The switching module 15 includes a first housing 22, at least one input 25, at least one output 30, a switching component 35, and a trip system 40.

[0034] The first housing 22 at least partially houses the or each input 25, the or each output 30, the switching member 35, and the tripping system 40.

[0035] The first housing 22 is configured to electrically insulate the interior of the first housing 22 from the exterior of the first housing 22.

[0036] The number of inputs 25 and the number of outputs 30 are both equal to the number of poles of switching device 10, which is 1 here.

[0037] Input 25 is conductive and is configured to be connected to a first device external to switching device 10. Specifically, input 25 is configured to receive current from this external device.

[0038] Input 25 includes, for example, an input connection terminal designed to allow an electrical conductor or connector to be connected to the input terminal to electrically connect a first external device to input 25.

[0039] Input 25 includes one or more electrical conductors connected together.

[0040] Input 25 passes through, for example, the first housing 22 to allow it to be connected to a first external device.

[0041] As a variation, the input 25 is fully housed within the first housing 22, but a portion of the input 25 intended for connection to a first external device is arranged as an opening facing the first housing 22 to allow an electrical conductor to be introduced into the first housing 22.

[0042] The first external device can be of any type, such as a power distribution network.

[0043] Output 30 is configured to receive current from input 25 via switching member 35. Furthermore, output 30 is configured to transmit this current to a second device external to switching device 10, and output 30 is configured to be connected to this second device.

[0044] Output 30 includes, for example, an output connection terminal designed to allow an electrical conductor or connector to be connected to the output terminal to electrically connect a second external device to output 30.

[0045] Output 30 passes through, for example, the first housing 22 to allow it to be connected to a second external device. As a variation, output 30 is fully housed in the first housing 22, but a portion of output 30 intended for connection to the second external device is arranged facing a hole in the first housing 22 to allow an electrical conductor to be introduced into the first housing 22.

[0046] The second external device can be of any type, such as a household power grid, or even a device that consumes electrical energy.

[0047] As is known per se, the switching member 35 is configured to switch between a first position and a second position.

[0048] When the switching component 35 is in the first position, the switching component 35 electrically connects the input 25 and the output 30.

[0049] When the switching member 35 is in the second position, the switching member 35 electrically isolates the input 25 and the output 30.

[0050] As is known per se, the switching member 35 specifically includes an electrical conductor that is movable between a position where the electrical conductor is simultaneously connected to the input 25 and the output 30, and a position where the electrical conductor is disconnected from at least one of the input 25 and the output 30.

[0051] The switching member 35 also includes a mechanism for moving the movable conductor between its two positions.

[0052] As is known to the public, the tripping system 40 is configured to command the switching component 35 to switch from the first position to the second position and vice versa.

[0053] Specifically, the tripping system 40 includes a tripping mechanism 45, a manual control component 50, a first thermal tripping subsystem 55, and a second magnetic tripping subsystem 60.

[0054] Due to the presence of the two subsystems 55 and 60, the switching module 15 is generally referred to as a "thermal-magnetic circuit breaker," especially when it forms a separate device from the diagnostic device 20. When the two components 15 and 20 form the same device contained in the same housing, the switching device 10 as a whole is referred to as a "thermal-magnetic circuit breaker."

[0055] The tripping mechanism 45 is configured to act on the switching member to switch the switching member 35 between its two positions.

[0056] The manual control component 50 is configured to be actuated by an operator to command the switching component 35 to switch from the first position to the second position via the trip mechanism 45, and vice versa.

[0057] The manual control component 50 includes, for example, a handle that can be actuated by rotating about an axis between two positions, each position corresponding to the position of the switching component 35.

[0058] As a variation, the manual control member 50 includes at least one button configured to drive the switching member 35 to switch from one position to another when pressed by an operator. According to one embodiment, the manual control member 50 includes two buttons, one of which drives switching from a first position to a second position, and the other button drives switching from a second position to a first position, when pressed by an operator.

[0059] It should be noted that many different types of manual control components 50 can be envisioned.

[0060] The first subsystem 55 is configured to command the switching component 35 to switch from the first position to the second position when the first criterion is met.

[0061] The first criterion is the fact that the first temperature of the switching module 15 is greater than or equal to the temperature threshold.

[0062] For example, as is known per se, the first subsystem 55 includes a bimetallic strip, which, for example, forms part of a circuit connecting the switching member 35 to the output 30, and is configured to allow current circulating from the input 25 to the output 30 to pass through it when the switching member 35 is in a first position (or in contact with a conductor through which the current flows). The bimetallic strip is configured to deform according to its temperature and act on a tripping mechanism 45 to switch the switching member 35 to its second position when the temperature of the bimetallic strip is greater than or equal to a temperature threshold. The first temperature is the temperature of the bimetallic strip.

[0063] As is known in itself, a temperature threshold is selected such that, during normal operation of switching device 10 under nominal conditions, when the current intensity is equal to or greater than the first current threshold for a predetermined time, the Joule effect causes the first temperature to increase to the temperature threshold.

[0064] The scheduled time depends on factors such as operating conditions and the setting of the bimetallic strip.

[0065] According to the IEC 60898-1 standard, at the reference temperature (or “rated”) of device 10, the first current threshold is, for example, between 1.05 and 1.3 times the maximum acceptable current without tripping. However, the first threshold may vary.

[0066] It should be noted that other types of first subsystems that command switching when the first temperature reaches the temperature threshold can also be envisioned, especially systems that do not include any bimetallic strips.

[0067] The second subsystem 60 is configured to command the switching component 35 to switch from the first position to the second position when the second criterion is met.

[0068] The second criterion is that the magnetic field generated by the current circulating between input 25 and output 30 is greater than or equal to the magnetic field threshold.

[0069] For example, switching module 15 includes a coil in which current (or a portion of the current in the coil connected in parallel with another conductor) circulates. The magnetic field generated by the coil acts on a movable element of the second subsystem 60. When the magnetic field is greater than or equal to a magnetic field threshold, the force exerted on the movable element by the magnetic field drives its displacement, and this displacement acts on tripping mechanism 45 to command switching member 35 to switch to its second position.

[0070] Choose a magnetic field threshold such that when the current exhibits an intensity value equal to the second current threshold, the current generates a magnetic field equal to the magnetic field threshold.

[0071] The second current threshold is significantly greater than the first current threshold. For example, the second current threshold is 3 to 10 times the rated value. Therefore, when either the first or second criterion is met, or when both criteria are met, the tripping system 40 commands the switching component 35 to switch to its second position.

[0072] The diagnostic device 20 is configured to detect the switching of the switching component 35, perform switching diagnostics, and transmit diagnostic data to a device 62 outside the switching device 10.

[0073] Device 62 is, for example, a computer or server equipped with a human-machine interface, and is designed to transmit received data to the operator, for example, by displaying data on the screen of the human-machine interface.

[0074] The phrase "perform a switch diagnosis" is understood to mean that the diagnostic device 20 attributes the detected switch to the following reasons:

[0075] - Tripping caused by the first standard, i.e., tripping caused by the first subsystem 55 due to the first standard being met or already met;

[0076] - Tripping caused by the second standard, i.e., tripping due to the satisfaction or having been satisfied of the second standard, caused by the second subsystem 60; and

[0077] - Manual tripping is caused by the operator activating the manual control component 50.

[0078] Diagnostic data includes, for example, identifiers of the switching reason, such as “1”, “2”, or “3”, or any indication that allows device 62 to identify the detected switching reason from three possible reasons.

[0079] Diagnostic data may optionally include additional information such as: instantaneous switching time, voltage or current values ​​measured at the instant the trip system 40 commands the switching. Diagnostic device 20 includes a second housing 64, a switching sensor 65, a temperature sensor 70, a current sensor 75, and a controller 80.

[0080] The second housing 64 at least partially houses the switching sensor 65, the temperature sensor 70, the current sensor 75, and the controller 80.

[0081] The second housing 64 is configured, for example, to hold the switching sensor 65, temperature sensor 70, current sensor 75 and controller 80 in appropriate positions relative to each other.

[0082] The second housing 64 is secured to the first housing 22, for example, by one or more hooks, and possibly by one or more electrical conductors. As a variation, both the second housing 64 and the first housing 22 are secured to the same support member designed to hold them in place relative to each other.

[0083] It should be noted that embodiments of the diagnostic device 20 without housing 64 are also conceivable. In this case, for example, the switching sensor 65, temperature sensor 70, current sensor 75, and controller 80 are housed in housing 22.

[0084] The switching sensor 65 is configured to measure information related to the switching of the switching member 35 and send a signal to the controller 80 that the switching member 35 has switched.

[0085] The switching sensor 65 is mechanically connected to the switching member 35, for example, and is partially movable thereto, so as to actuate a module that generates an electrical signal, which is a function of the position of the switching member 35.

[0086] As a variant, the switching sensor 65 is configured to estimate the position of the switching member 35 by evaluating whether the current circulates between the input 25 and the output 30.

[0087] As a variation, the switching sensor 65 detects the position of the manual control component 50 by electrical contact, and the manual control component 50 itself is integrated with the position of the switching component 35.

[0088] Typically, many types of switching sensors may be used 65.

[0089] Temperature sensor 70 is configured, for example, to use a thermocouple to measure the value of a second temperature of switching device 10.

[0090] The second temperature is measured, for example, inside the second housing 64. In this case, the second temperature is the temperature of the diagnostic device 20.

[0091] As a variation, the second temperature is the temperature of the switching module 15, such as the temperature of the electrical conductor of the switching module 15, particularly the temperature of the input 25 or the output 30. In this case, the temperature sensor 70 contacts at least a portion of the switching module 15, particularly at least a portion of the electrical conductor, by passing through at least the second housing 64 and optionally through the first housing 22.

[0092] Specifically, the second temperature is the temperature whose change is related to the change of the first temperature. For this reason, the temperature sensor 70 is typically located very close to the bimetallic strip, for example, at a distance of one centimeter or less.

[0093] The current sensor 75 is configured to measure the intensity of the current flowing through the switching module 15 from input 25 to output 30.

[0094] For example, the current sensor 75 is configured to periodically measure the intensity value over time. The measurement frequency is, for example, greater than or equal to 1 kHz, such as 20 kHz.

[0095] The current sensor 75 includes, for example, a sensor 85 and an analog-to-digital converter 90. The sensor 85 is configured to measure the intensity value in analog form, and the analog-to-digital converter 90 is configured to convert the measured value into a digital signal and transmit the digital signal to the controller 80. It should be noted that the controller 80 and the analog-to-digital converter 90 are sometimes one and the same element performing both functions.

[0096] Optionally, before transmitting the measured value to the controller 80, the current sensor 75 performs frequency filtering of the measured value, such as a bandpass filter around the expected frequency of the current.

[0097] Define a saturation value for current sensor 75.

[0098] The saturation value is the maximum intensity value (absolute value) that the current sensor 75 is designed to measure. For example, when the current exhibits an intensity value whose absolute value is greater than or equal to the saturation value, the current sensor 75 generates a signal indicating that the intensity (absolute value) of the current is equal to the saturation value.

[0099] In other words, the saturation value makes the current sensor 75 unable to distinguish between two currents that exhibit an absolute value greater than the saturation value.

[0100] Sensor 85 includes, for example, a conductive loop surrounding a conductor (e.g., a conductor forming part of input 25 or output 30) of switching module 15, and is configured to generate a current based on a magnetic field generated by a current circulating in said conductor. Measurement of the current intensity generated by this loop can estimate the value of the magnetic field, thereby estimating the intensity of the current in the conductor.

[0101] It should be noted that many types of current sensors 75 can be used, such as shunt sensors or current transformers, which are known to those skilled in the art.

[0102] The controller 80 is configured to detect the switching of the switching member 35 based at least on information transmitted by the switching sensor 65.

[0103] In addition, the controller 80 is configured to receive measured intensity and second temperature values, and to diagnose detected switching based on the received intensity and second temperature values.

[0104] The controller 80 includes, for example, a processor 95 and a memory 100.

[0105] The memory 100 contains software instructions configured to implement a method for diagnosing the switching of the switching device 10 when executed on the processor 95.

[0106] The controller 80 is configured to communicate with the external device 62, for example, via a wireless data link or even via a wired network.

[0107] As a variant, the controller 80 is formed from an application-specific integrated circuit (“Application-Specific Integrated Circuit”), a collection of programmable logic components, or even a collection of any electronic components.

[0108] Now refer to Figure 2 Describe the operation of diagnostic device 20. Figure 2 A flowchart illustrating the steps of the diagnostic method implemented by the device 20.

[0109] The diagnostic method includes an initial step 200, a detection step 205, a first calculation step 210, a first estimation step 215, a second estimation step 220, a first comparison step 225, a first diagnostic step 230, a second calculation step 235, a determination step 240, a third calculation step 245, a second comparison step 250, a second diagnostic step 255, and a third diagnostic step 260.

[0110] At the start of the initial step 200, the switching member 35 is in the first position, and current flows from the input 25 through the switching member 35 to the output 30.

[0111] For example, electric current is alternating current exhibiting a nominal period. For instance, the nominal period is equal to 50 hertz (Hz), but it may vary in different devices.

[0112] In the initial step 200, at least one second temperature value is measured by the temperature sensor 70 and transmitted to the controller 80, specifically the second diagnostic module 110.

[0113] For example, the value of the second temperature is measured periodically by temperature sensor 70, with a time period, for example, between 100 milliseconds (ms) and 10 seconds, although these values ​​may vary, particularly depending on the heat capacity of the bimetallic strip. Furthermore, current sensor 75 measures at least one value of the intensity of the current circulating between input 25 and output 30. For example, the intensity value is measured periodically by current sensor 75. As a variation, the intensity value is measured continuously by current sensor 75, for example, over a sliding time window.

[0114] The initial step 200 is performed until a switch occurs from the first position to the second position of the switching member 35. This is in Figure 2 The middle part is represented by arrow 265.

[0115] Assume a switch occurs during initial step 200.

[0116] The switching is driven by the switching sensor 65 to transmit at least one signal indicating that a switching has occurred to the controller 80.

[0117] The controller 80 switches after receiving a signal from the switching sensor 65.

[0118] After detecting the switch, the controller 80 performs detection step 205.

[0119] During detection step 205, controller 80 detects whether current sensor 75 is saturated in the first time immediately before switching.

[0120] For example, the first time band has a predetermined duration and ends at the moment of switching.

[0121] According to one embodiment, a first time band is defined as a time band during which a predetermined number of intensity values ​​are measured, wherein the most recent value measured during the first time band is the last non-zero value measured (because of the switching off current).

[0122] The first time band is, for example, a time band whose duration is equal to the nominal half-cycle of the current and ends at the instant of switching. As a variation, the duration of the first time band is equal to multiple nominal half-cycles, such as 5 half-periods.

[0123] For example, if the current sensor 75 transmits multiple consecutive intensity values ​​to the controller 80, and these intensity values ​​are equal to each other and their absolute values ​​are equal to the saturation value, then saturation is detected. As a variation, the saturation value is an estimate slightly lower than the actual saturation threshold, and then if the current sensor 75 sends multiple consecutive intensity values ​​to the controller 80, and these intensity values ​​are greater than or equal to the saturation value, then saturation is detected.

[0124] If saturation is detected, proceed to the first calculation step 210. Otherwise, proceed to the first estimation step 215.

[0125] During the first calculation step 210, the controller 80 calculates at least one value of the time derivative of the measured intensity.

[0126] For example, the controller 80 calculates the value of the time derivative of the intensity at the instant when the intensity is equal to zero during the first time band, especially at the instant when the intensity is equal to zero and the intensity value increases with time.

[0127] As a variation, controller 80 calculates the value of the time derivative of the intensity, which corresponds to each instant during which the intensity value is measured in the first time band.

[0128] The first calculation step 210 is followed by the second estimation step 220.

[0129] During the second estimation step 220, the intensity value is estimated by the controller 80. It is worth noting that the estimated value is the maximum value of the current intensity during the first time band.

[0130] The estimated intensity value is estimated from at least one calculated time derivative value, particularly from the time derivative value at the time when the intensity is zero.

[0131] As a variant, the estimated intensity value is estimated from the maximum derivative (absolute value) among the calculated derivative values.

[0132] For example, the estimated intensity value can be estimated by considering that the intensity of the current is a sinusoidal function of time, and by calculating the estimated intensity value from the knowledge of the value of the derivative at the instant when the intensity equals zero.

[0133] For example, the maximum derivative value is considered to be the derivative value at the instant when the intensity is equal to zero and increases with time, because these confirmations are correct when the current is a sinusoidal function of time.

[0134] The second estimation step 220 is followed by the first comparison step 225.

[0135] During the first estimation step 215, the controller estimates the maximum value of the intensity.

[0136] The maximum intensity is, for example, the highest of the intensity values ​​measured during the first time band. As a variation, the maximum intensity is estimated by interpolation or extrapolation based on the measured intensity values, by considering that the current is a sinusoidal function of time.

[0137] The first estimation step 215 is followed by the first comparison step 225.

[0138] During the first comparison step 225, the intensity value estimated during step 215 or 220 is compared with the second current threshold.

[0139] If the estimated intensity value is greater than or equal to the second current threshold, the first diagnostic step 230 is performed. Otherwise, the controller 80 determines that no switching has occurred due to the second criterion being met, and performs the second calculation step 235.

[0140] During the first diagnostic step 230, the controller 80 diagnoses the switch as being caused by a second criterion. In other words, the controller 80 concludes that the switch was caused by the second trip subsystem 60 because the magnetic field generated by the current is greater than or equal to the magnetic field threshold.

[0141] During the first diagnostic step 230, the controller 80 generates and sends a diagnostic message to the remote device 62, which indicates that the switching was caused by the second subsystem 60.

[0142] As a variation, the diagnostic device 20 may, for example, send a signal to the operator indicating the reason for the switch by displaying a message on the screen of the diagnostic device 20, or even by displaying an indicator (such as a colored movable element visible from the outside of the diagnostic device 20) and indicating the reason for the switch.

[0143] During the second calculation step 235, the controller 80 calculates the average value of the second temperature.

[0144] This average is, for example, the arithmetic mean of the second temperature values, that is, the average calculated by summing multiple second temperature values ​​and dividing the sum by the number of values ​​to be summed.

[0145] The average value is calculated, for example, based on the second temperature value continuously acquired during the second time zone.

[0146] The second time zone, for example, has a predetermined duration and is defined as the first time zone having that duration and ending at the moment of switching.

[0147] According to one embodiment, the second time band is defined as a time band during which a predetermined number of intensity values ​​are measured, and the most recent value measured during the second time band is the last non-zero value measured (because of the switching off current).

[0148] For example, the duration of the second time band is between 0 and 1 second.

[0149] The second calculation step 235 is followed by the determination step 240.

[0150] During step 240, the controller 80 determines a third current threshold based on the calculated average second temperature value.

[0151] It should be noted that, as a variation, the third threshold is determined based on a single second temperature value measured, for example, at the moment of switching.

[0152] The third current threshold causes the first temperature to increase to the temperature threshold when the current intensity is equal to or greater than the third current threshold for a predetermined time and when the second temperature is equal to the calculated average second temperature value.

[0153] In other words, the third current threshold is calculated to take into account the fact that, under the actual operating conditions of the switching module 15, the switching module 15 may be heated or cooled by external factors, and therefore, the relationship between the current intensity and the first temperature may be different from that considered when setting the temperature threshold.

[0154] For example, if the temperature threshold is set such that the first subsystem 55 trips the switching component 35 when the current intensity equals the first threshold for a predetermined time, and the switching module 15 is placed alone in the middle of a 3-meter cubic volume of air at 15°C (these values ​​are examples that may vary), if the switching module 15 is heated above 15°C, for example by adjacent equipment or in summer, the trip will occur at a lower intensity. Conversely, in winter or in the presence of heavy airflow, the trip will occur at a higher intensity.

[0155] The third current threshold is determined, for example, by the average second temperature value and a table stored in memory 100, which contains a corresponding third threshold for a plurality of stored second temperature values.

[0156] As a variation, for each second temperature value stored in the table, the table contains a coefficient, such that the third threshold is determined by multiplying the first threshold by the coefficient.

[0157] Each coefficient value is strictly greater than zero.

[0158] For example, for a stored second temperature value that is strictly greater than the expected second temperature value when the switching device 10 is placed alone in the middle of a 3-meter cubic air chamber at 15°C, the corresponding coefficient value is strictly less than 1. For a stored second temperature value that is strictly lower than the expected second temperature value when the switching device 10 is placed alone in the middle of a 3-meter cubic air chamber at 15°C, the corresponding coefficient value is strictly greater than 1.

[0159] When the average second temperature value lies precisely between two consecutive second temperature values ​​stored in the table, the third threshold is calculated, for example, by interpolating from two third thresholds corresponding to the two stored consecutive second temperature values, or by interpolating from two coefficient values ​​corresponding to these consecutive values.

[0160] As a variation, if the average second temperature value lies precisely between two consecutive second temperature values ​​stored in the table, then the determined third threshold is the third threshold corresponding to the stored second temperature value that is closest to the average value.

[0161] This table, for example, was experimentally determined by measuring the strength of the trip switching of the first subsystem 55 for each stored second temperature value.

[0162] The difference between consecutive second temperature values ​​stored in the table is, for example, between 1 degree Celsius (°C) and 10°C, or equal to 5°C.

[0163] As a variation, the third threshold is calculated by a function stored in memory 100, and the value of the third threshold is correlated with the measured second temperature, for example, determined experimentally. This function is, for example, an affine function defined by two coefficients stored in memory 100.

[0164] It should be noted that, according to one possible variation, the third threshold is calculated from a single measured second temperature value rather than an average value.

[0165] Generally speaking, it should be noted that the third threshold may be calculated or determined in different ways based on one or more second temperature values.

[0166] The third calculation step 245 is performed immediately after step 240 is determined.

[0167] During the third calculation step 245, the average strength value is calculated.

[0168] For example, the average intensity is calculated over the second time band.

[0169] The average intensity value is calculated, for example, from multiple consecutive RMS (root mean square) values, such as by the arithmetic mean of the RMS values.

[0170] The number of consecutive RMS values ​​involved in calculating the average intensity value is, for example, between 0 and 10, such as equal to 5.

[0171] According to one embodiment, in the initial step 200, the controller 80 periodically calculates the RMS value based on, for example, N intensity values ​​(N is an integer strictly greater than 1) continuously measured by the current sensor 75.

[0172] As is known by itself, the RMS value is calculated by taking the square root of the average of the squares of the measured values, for example, the square root of the ratio between the sum of the squares of the N intensity values ​​as the numerator and the number N as the denominator.

[0173] The number N is, for example, equal to the number of intensity samples collected during the nominal period of the current. In this case, when the nominal frequency of the current is between 45 Hz and 66 Hz and sampling is performed at 20 kHz, the number N is specifically between 303 and 444.

[0174] The third calculation step 245 is followed by the second comparison step 250.

[0175] During the second comparison step, the controller 80 compares the calculated average intensity value with the third threshold.

[0176] If the average intensity value is greater than or equal to the third threshold, proceed to the second diagnostic step 255. Otherwise, proceed to the third diagnostic step 260.

[0177] During the second diagnostic step 255, the controller 80 diagnoses the switch as being caused by a first criterion. In other words, the controller 80 concludes that the switch was caused by the first trip subsystem 55 because the first temperature is greater than or equal to a temperature threshold.

[0178] During the second diagnostic step 255, the controller 80 generates a diagnostic message and transmits it to the remote device 62, the diagnostic message indicating that the switch was caused by the first subsystem 55.

[0179] During the third diagnostic step 260, the controller 80 diagnoses the switch as a switch caused by the operator activating the manual control component 50.

[0180] During the third diagnostic step 260, the controller 80 generates a diagnostic message and transmits it to the remote device 62. The diagnostic message indicates that the switching was caused by the manual control component 50.

[0181] With the aid of the present invention, the diagnostic device 20 can effectively distinguish between trips caused by subsystems 55 and 60 or by the manual control component 50, even when the switching device 10 is placed in an environment where the nominal conditions relative to the selected temperature threshold may become hotter or colder.

[0182] This significantly avoids the situation where the diagnostic device 20 attributes the tripping to an error, because the temperature of the switching device 10 is either higher or lower than the nominal conditions. In fact, considering the second temperature makes it possible to take into account the fact that the diagnostic device 10 is placed under temperature conditions different from those initially calibrated for the first tripping subsystem 60.

[0183] Therefore, the information transmitted to the operator of the device that must intervene, including the switching device 10, is more accurate, which makes the intervention more relevant, faster, and, most importantly, safer (because certain actions associated with a particular tripping cause may prove dangerous for other causes).

[0184] The fact that a third threshold is calculated based on one or more measured second temperature values ​​makes it possible to accurately consider the effect of the temperature of the diagnostic device 10 on the operation of the subsystem 55.

[0185] Using a table containing a third threshold value based on the measured second temperature value makes it easy and quick to calculate the third threshold without requiring high computational power.

[0186] The use of the average value of the second temperature accurately reflects the effect of the second temperature on the operation of subsystem 55.

[0187] When calculating the maximum intensity value from the derivative of the measured intensity value, the maximum value can be calculated accurately even if the maximum value exceeds the saturation value of the current sensor 75.

[0188] However, in the absence of saturation, treating the maximum value directly as the highest value among the measured values ​​allows for faster and more accurate processing than using derivatives.

[0189] Using the maximum value of the derivative is more accurate than using other values ​​of the derivative when calculating the maximum value of the intensity.

[0190] Comparing the maximum intensity with a second current threshold makes it easy and quick to detect switching according to the second standard.

[0191] When it is determined that neither the first nor the second criterion applies, the switching caused by the manual control component 50 can be easily and simply detected, rather than providing specific procedures, such as using a specific sensor to detect the actuation of component 50. The switching device 10 is significantly simplified because such a specific sensor is not required.

[0192] When the second temperature is the temperature of the diagnostic device 20, the diagnostic device 20 is particularly easy to manufacture because there is no need to provide the temperature sensor 70 with access to the switching module 15 (for example). Furthermore, the temperature sensor 70 can be arranged within a possible housing 64 and thus protected, especially when the device 20 and module 15 are two separate units housed in different housings.

[0193] The diagnosis is more accurate when the second temperature is the temperature of the switching module 15, because the second temperature more accurately reflects the first temperature. For example, incorrect diagnoses can be avoided when the switching module 15 is not heated or cooled like the diagnostic device 10.

[0194] It should be noted that, according to a possible variation, a switch caused by the first criterion could likely be diagnosed by directly comparing a second temperature value (e.g., an average second temperature value) with a corresponding temperature threshold. For example, if the second temperature is the first temperature (specifically, if temperature sensor 70 begins measuring the temperature of the bimetallic strip or another element of the first subsystem 55), then the switch is diagnosed as being due to a switch of the first criterion if and only if the second temperature value is greater than or equal to the temperature threshold at which the subsystem 55 disconnects from the switch.

[0195] It should be noted that, according to a possible variation, steps 235 to 255 are not implemented. In this case, the diagnostic device 20 is simply configured to distinguish between a trip caused by the second criterion and a manual trip of component 50.

Claims

1. A diagnostic device (20) for a switching device (10), the switching device (10) including a switching module (15), the switching module (15) including an input (25), an output (30), a switching member (35), and a tripping system (40), the switching member (35) being configured to switch between a first position and a second position, wherein in the first position the switching member (35) is electrically connected to the input (25) and the output (30), and in the second position the switching member (35) electrically isolates the input (25) and the output (30), the tripping system (40) being designed to command the switching member (35) to switch from the first position to the second position, the tripping system (40) being a thermomagnetic tripping system, configured to command switching when one of a first criterion or a second criterion is met, the first criterion being the fact that a first temperature of an element of the tripping system (40) is greater than or equal to a temperature threshold, and the second criterion being the fact that a magnetic field is greater than or equal to a field threshold, the magnetic field being generated by a current circulating between the input and the output when the switching member (35) is in the first position. The diagnostic device (20) includes a controller (80) configured to detect the switching of the switching member (35) from a first position to a second position. The diagnostic device (20) is characterized in that it includes a temperature sensor (70) and a current sensor (75), the temperature sensor (70) being configured to estimate a second temperature value of the switching device (10), the current sensor (75) being configured to measure a value of the intensity of a current, and the controller (80) being configured to, after detecting a switching, diagnose the switching as a switching due to a first criterion based on at least one estimated second temperature value and when at least one intensity value is greater than or equal to a first current threshold, the first current threshold being a function of at least one of the estimated second temperature values.

2. The diagnostic device according to claim 1, wherein, The controller (80) includes a memory (100) and is configured to determine the first current threshold based on a table stored in the memory (100) containing a first current threshold based on a second temperature, or based on a function stored in the memory that associates the first current threshold with a second temperature value.

3. The diagnostic device according to any one of claims 1 and 2, wherein, The controller (80) is configured to estimate at least one intensity value based on at least one value of the derivative of the intensity measured by the current sensor, and is configured to diagnose the switching as a switching due to a first criterion based on at least one estimated intensity value.

4. The diagnostic device according to claim 3, wherein, The controller (80) is configured as follows: - Detect saturation of the current sensor (75), estimate at least one intensity value from at least one value of the derivative of the measured intensity, and diagnose switching based at least on the estimated intensity value when saturation is detected, and - In the absence of saturation, the switching can be directly diagnosed based on at least one intensity value measured by the current sensor (75).

5. The diagnostic device according to claim 3, wherein, The current is an alternating current that exhibits a time period. Each estimated intensity value is estimated based on the derivative of the intensity, which is the maximum derivative of the intensity over the time period of the current. Each intensity value is estimated by considering the intensity as a sine function of time.

6. The diagnostic device according to any one of claims 1 to 2, wherein, At least one second temperature value is the average value of the second temperature during the time band prior to the switch.

7. The diagnostic device according to any one of claims 1 to 2 and 4 to 5, wherein, The controller (80) is also configured to compare at least one intensity value of the current with a second current threshold, and is configured to diagnose a switching due to a second criterion when the intensity value is greater than or equal to the second current threshold.

8. The diagnostic device according to claim 7, wherein, The tripping system (40) includes a component (50) configured to command a switch based on an operator's command, and a controller (80) configured to diagnose a switch as a switch commanded by the operator if the controller does not diagnose the switch as a switch caused by a first criterion or a second criterion.

9. The diagnostic device according to any one of claims 1 to 2, 4 to 5 and 8, wherein, The second temperature is the temperature of the diagnostic device (20).

10. The diagnostic device according to any one of claims 1 to 2, 4 to 5 and 8, wherein, The second temperature is the temperature of the switching module (15).

11. A switching device (10) comprising a switching module (15) including an input (25), an output (30), a switching member (35), and a tripping system (40), the switching member (35) being configured to switch between a first position and a second position, wherein in the first position the switching member (35) is electrically connected to the input (25) and the output (30), and in the second position the switching member (35) electrically isolates the input (25) from the output (30), the tripping system (40) being designed to command the switching member (35) to switch from the first position to the second position, the tripping system (40) being a thermomagnetic tripping system configured to command switching when one of a first criterion or a second criterion is met, the first criterion being the fact that a first temperature of an element of the tripping system (40) is greater than or equal to a temperature threshold, and the second criterion being the fact that a magnetic field is greater than or equal to a field threshold, the magnetic field being generated by a current circulating between the input and the output when the switching member (35) is in the first position, the switching device (10) comprising a diagnostic device (20) according to any one of claims 1 to 10.

12. The switching device according to claim 11, wherein, The diagnostic device (20) includes a first housing (64) containing a controller (80), and the switching module (15) includes a second housing (22) containing a switching member (35) and a tripping system (40). The first housing (64) is different from the second housing (22) and is configured to be fixed to the second housing (22).

13. The switching device according to claim 11, comprising a single main housing containing a diagnostic device (20) and a switching module (15).

14. A method for diagnosing switching of a switching device (10), the switching device (10) including a switching module (15), the switching module (15) including an input (25), an output (30), a switching member (35), and a tripping system (40), the switching member (35) being configured to switch between a first position and a second position, wherein in the first position the switching member (35) is electrically connected to the input (25) and the output (30), and in the second position the switching member (35) electrically isolates the input (25) from the output (30), the tripping system (40) being designed to command the switching member (35) to switch from the first position to the second position, the tripping system (40) being a thermomagnetic tripping system, configured to command switching when one of a first criterion or a second criterion is met, the first criterion being the fact that a first temperature of an element of the tripping system (40) is greater than or equal to a temperature threshold, and the second criterion being the fact that a magnetic field is greater than or equal to a field threshold, the magnetic field being generated by a current circulating between the input and the output when the switching member (35) is in the first position. This method is implemented by a diagnostic device (20) comprising a controller (80), a current sensor (75), and a temperature sensor (70). The method includes the following steps: -At least one value of the second temperature of the switching device is measured by the temperature sensor (70) (200). - The controller (80) detects the switching of the switching member (35) from the first position to the second position, and - The controller (80) will perform a switching diagnosis (255) as a switching due to a first criterion when at least one intensity value is greater than or equal to a first current threshold, based on at least one estimated second temperature value, wherein the first current threshold is a function of at least one of the estimated second temperature values.

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