System for a cable section, transmission system for transmitting electrical energy and method for operating the system

Abstract

The invention relates to a system for a cable section for transmitting electrical energy, having a first sensor for detecting an electrical signal of the cable section, a processor unit, a data memory and a signal interface, the data memory storing a first curve set consisting of a plurality of first curves with an associated distance, each first curve representing a predetermined impulse response of an electrical pulse by means of a cable model of the cable section, the electrical pulse being caused by a modeled partial discharge, the first sensor being configured to detect a first discharge signal and to transmit a first measurement signal representing it to the processor unit, the processor unit being configured to determine, on the basis of the first measurement signal, a first curve of the first curve set as a first discharge curve, which first discharge curve is best correlated with the first discharge signal in the first curve set, the processor unit being configured to determine a first sensor distance of an actual partial discharge on the basis of the distance to which the first discharge curve belongs.

Description

Technical Field

[0001] The present invention relates to a system for a cable segment for transmitting electrical energy, a transmission system for transmitting electrical energy, and a method for operating the system for transmitting electrical energy. Background Technology

[0002] Cable segments for transmitting electrical energy are known in the prior art. A cable segment can consist of a single cable section or multiple cable sections coupled sequentially. A cable segment can also be called a cable. Electrical energy can be transmitted through a cable segment using either direct current (DC) or alternating current (AC). For transmitting electrical energy over long distances, very high voltages are typically used. In this case, the cable segment can be constructed as a high-voltage cable. A cable segment typically includes a conductive core, which can be formed from multiple individual conductive cores. Multiple layers of different materials and / or different functions are typically arranged around the core. One of these layers can be an insulating layer. In practice, a phenomenon known as partial discharge may occur. This partial discharge causes a jumping electrical signal that propagates in the opposite direction of the cable segment from the point of partial discharge (also called the partial discharge location). The signal caused by partial discharge is also called a partial discharge signal. Partial discharge signals can be detected using sensors at the ends of the cable segment. However, it should be considered that, due to the physical characteristics of the cable segment, the partial discharge signal undergoes attenuation and dispersion along the path between the partial discharge location and the sensor. Attenuation and dispersion depend, for example, on the frequency components of the pulses caused by partial discharge, the cable segment's structural design, the cable segment's laying type, the cable segment's temperature, and / or the cable segment's service life. Furthermore, a single sensor at one end of the cable segment is insufficient. More precisely, a second sensor is needed at the opposite end of the cable segment to calculate where the partial discharge occurs or its location via propagation time and triangulation. Due to the correlation between attenuation and dispersion of the partial discharge signal, a non-negligible deviation often occurs between the calculated and actual partial discharge locations. In addition to the aforementioned attenuation and dispersion, it is also possible that the partial discharge signal undergoes strong dispersion and / or attenuation, especially frequency-dependent attenuation, making it unrecognizable as a pulse signal by sensors and / or evaluation equipment. Therefore, there is a danger of unrecognized partial discharges occurring in the cable segment. If multiple such partial discharges occur at the same location, this can lead to non-negligible damage to the cable segment, which must be avoided. Summary of the Invention

[0003] The objective of this invention is to provide a system and a method that allow for reliable identification of partial discharges and accurate determination of the distance between the location of the partial discharge and the sensor.

[0004] According to a first aspect of the invention, the aforementioned task is solved by a system according to the invention. Therefore, a system for transmitting electrical energy in a cable segment is provided. The system includes a first sensor for detecting electrical signals in the cable segment, a processor unit, a data memory, and a signal interface. The data memory stores a first set of curves consisting of a plurality of first curves, each carrying a corresponding distance to the first sensor, wherein each first curve represents a predetermined pulse response of an electrical pulse by means of a cable model of the cable segment, the electrical pulse being caused by a modeled partial discharge on the cable segment at a distance to the first sensor corresponding to the respective first curve. The first sensor is configured to detect an electrical signal, referred to as a first discharge signal, caused by an actual partial discharge on the cable segment. Furthermore, the first sensor is configured to directly or indirectly transmit a first measurement signal to the processor unit, wherein the first measurement signal represents the first discharge signal. The processor unit is configured to determine, based on the first measurement signal, a first curve in the first set of curves as the first discharge curve, the first discharge curve being optimally correlated with the first discharge signal among the first curves in the first set of curves. Which curve in the first set of curves best matches or correlates with the first discharge signal can be determined by applying a similarity metric, such as Euclidean distance, Mahalanobis distance, and / or cosine similarity, in the feature space. The processor unit is configured to determine the actual partial discharge to the first sensor distance based on the distance to which the first discharge curve belongs. The signal interface is implemented to transmit an output signal representing the first sensor distance.

[0005] Research has shown that partial discharges on cable segments can be modeled using electrical pulses. Furthermore, it has been found that cable segments can be modeled using a mathematical model, i.e., a cable model, which can be set with multiple parameters. These parameters can be set to make the model model the actual cable segment. If this cable model is now used to induce partial discharges at the modeled location of the partial discharge on the modeled cable segment, the same cable model can be used to obtain the pulse response at one end of the cable segment or at another sensor location on the cable segment. The pulse response, or at least a portion of the pulse response, then forms a curve. The pulse response or curve changes as the distance between the modeling location for the sensor and the modeling location for the feed electrical pulse changes. Therefore, it is possible to obtain corresponding curves for multiple different distances using the cable model. These curves can form multiple first curves, each with its corresponding distance to a first sensor, and these first curves are stored in a data memory. The first curves differ not only in their spectral density but also in their amplitude spectrum. For example, it has been found that the greater the modeling distance between the partial discharge location and the sensor, the lower the frequency of the curve's spectrum and the smaller the maximum amplitude.

[0006] Therefore, in terms of the system, it is preferably specified that the data storage device stores a first curve set consisting of at least 10, at least 20, or at least 30 first curves. The distances to the sensors corresponding to the first curves can form a sequence of correspondingly larger distances, wherein the distances are implemented at equal intervals.

[0007] When the first sensor detects an electrical signal on the cable segment, the signal can be compared with a first curve to determine which curve best fits the detected signal. This curve is associated with a distance stored in the data memory. This distance corresponds to the actual distance between the first sensor and the actual partial discharge on the cable segment.

[0008] Therefore, it is specified that the first sensor is configured to detect an electrical signal, referred to as the first discharge signal, caused by an actual partial discharge on the cable segment. Furthermore, the first sensor can transmit a first measurement signal to the processor unit, wherein the first measurement signal represents the detected first discharge signal. The first discharge signal is typically an analog signal. Conversely, the first measurement signal is preferably a digital signal. This provides the advantage that no degradation of information about the detected first discharge signal occurs during transmission to the processor unit. Therefore, the first sensor can be configured to digitize the detected first discharge signal and thereby form the first measurement signal.

[0009] By transmitting the first measurement signal to the processor unit, the processor unit obtains not only information about the first measurement signal itself, but also information about the first discharge signal represented by the first measurement signal. Therefore, the processor unit can identify the curve that best reflects the detected first discharge signal from a plurality of first curves in the first set of curves. Thus, the processor unit is configured to determine, based on the first measurement signal, the first curve among the plurality of first curves as the first discharge curve, which is best correlated with the first discharge signal among the first curves in the first set of curves. Therefore, the processor unit can, for example, be configured to perform autocorrelation on each first curve having the first discharge curve, such that an autocorrelation value is generated by implementing each autocorrelation function. The first curve (on which the maximum autocorrelation value is obtained) is the curve among the first curves in the first set of curves that is best correlated with the first discharge signal. However, in principle, other methods exist for determining the curve among the first curves in the first set that is best correlated with the first discharge signal. The corresponding curve is referred to as the first discharge curve.

[0010] The processor unit is preferably coupled to a data memory, enabling the processor unit to access the data memory. Specifically, the processor unit can be configured to read data from the data memory regarding a first curve and its associated distance. As previously described, the processor unit is configured to determine a first discharge curve. This first discharge curve is the first of a plurality of first curves stored in the data memory. For each first curve, a distance representing the distance of the partial discharge to the sensor is stored in the data memory. The processor unit is therefore preferably configured to read the distance to which the first discharge curve belongs from the data memory. Thus, it is specified that the processor unit is configured to determine the first sensor distance from the actual partial discharge to the first sensor based on the distance to which the first discharge curve belongs. Preferably, the first sensor distance is the distance to which the first discharge curve belongs.

[0011] The first set of curves was previously determined using a cable model that can be adapted to actual cable segments with particular precision. Therefore, the actual attenuation and / or dispersion of the pulses formed by partial discharge can also be considered by the cable model. The first curves in the first set of curves preferably differ in their frequency and amplitude characteristics. This allows for particularly precise adjustment of the first curve in the first set that best matches the first discharge signal. Therefore, amplitude and frequency characteristics that influence which first curve is determined here as the first discharge curve are preferred. In practice, it has been found that the first discharge curve among multiple first discharge curves can be accurately determined such that the distance to the first sensor to which the first discharge curve belongs particularly accurately indicates the actual distance from the sensor to the partial discharge location where partial discharge occurred.

[0012] The system also has a signal interface configured to transmit an output signal representing the distance to the first sensor. Specifically, the output signal can be sent via the signal interface. This makes the distance to the first sensor accessible to other components, devices, and / or systems. In particular, the system can have additional modules and / or units configured for further processing of the first sensor distance. Therefore, it is also possible that the signal interface forms an integrated part of the processor unit. Thus, the processor unit and the signal interface can be constructed integratedly.

[0013] The system's first sensor can be configured to repeatedly and / or periodically detect electrical signals. This results in the determination of a first discharge curve and a first sensor distance with each detection of the electrical signal. The processor unit can be configured accordingly. Furthermore, the signal interface can be configured to transmit output signals, such that the latest sensor distance is transmitted respectively. The output signal can thus periodically transmit the previously determined first sensor distance. The advantage of periodically detecting electrical signals using the first sensor is that continuous monitoring of cable segments is possible using the system.

[0014] An advantageous embodiment of the system is characterized by having a second sensor for detecting electrical signals in a cable segment. The data memory preferably stores a set of second curves consisting of a plurality of second curves, each carrying a distance to the corresponding second sensor. Each second curve represents a predetermined pulse response of an electrical pulse, caused by a modeled partial discharge on the cable segment at a distance to the second sensor corresponding to the respective second curve. Furthermore, the first and second sensors can be fastened to the cable segment at predetermined sensor distances from each other. The second sensor is preferably configured to detect an electrical signal, referred to as a second discharge signal, caused by the same actual partial discharge on the cable segment. Furthermore, the second sensor is preferably configured to transmit a second measurement signal, representing the second discharge signal, directly or indirectly to a processor unit. The processor unit is preferably configured to determine, based on the second measurement signal, a second curve in the set of second curves as the second discharge curve best correlated with the second discharge signal. Which curve in the second set of curves best matches or correlates with the second discharge signal can be determined by applying a similarity metric, such as Euclidean distance, Mahalanobis distance, and / or cosine similarity, in the feature space. Furthermore, the processor unit is preferably configured to determine the actual partial discharge relative to the first sensor based on a predetermined sensor distance, the distance to which the first discharge curve belongs, and the distance to which the second discharge curve belongs.

[0015] Therefore, in addition to the first sensor, the system also has another sensor, namely a second sensor. The second sensor is also configured to detect electrical signals. The first and second sensors can be secured to the cable segment at a predetermined sensor distance. Preferably, the first sensor can be secured to a first end of the cable segment and the second sensor can be secured to the opposite second end of the cable segment. If a partial discharge occurs on the cable segment, the cable segment generates a pulsed signal, which is detected as an electrical signal by both sensors. However, especially due to attenuation and dispersion of the cable segment, different electrical signals reach the two sensors. If the distance between the partial discharge location and the first sensor is, for example, smaller than the distance to the second sensor, the first discharge signal has a larger amplitude in the high-frequency spectral components than the second discharge signal. Because the first and second discharge signals are often different in practice, a corresponding discharge curve can be determined for each of the two discharge signals.

[0016] Therefore, it is preferably specified that the data memory stores a second set of curves consisting of a plurality of second curves, each carrying a corresponding distance to the second sensor. Reference is made in a similar manner to advantageous descriptions, preferred features, technical effects, and / or advantages regarding the second set of curves, the second curves, and their corresponding distances, as has already been made regarding the first set of curves, the first curves, and their corresponding distances. In principle, it can be specified that the data memory thus stores both a first set of curves and a second set of curves. These two sets of curves can be different. However, it is also possible that the first set of curves and the second set of curves are the same. In this case, the data memory can store a common set of curves that forms both the first and second set of curves. A similar situation applies to the corresponding distances.

[0017] The second sensor can be constructed similarly to the first sensor. The advantageous descriptions, preferred features, technical effects, and / or advantages of the second sensor are therefore referenced in a similar manner to those described in conjunction with the first sensor. However, it should be noted that the first and second discharge signals are caused by the same actual partial discharge on the cable segment. Due to the often different distances from the partial discharge location to the two sensors and / or due to different physical conditions, the first discharge signal is largely different from the second discharge signal.

[0018] Therefore, it is also preferable that the processor unit is configured to determine the second discharge curve in the second curve set that is best correlated with the second discharge signal. Furthermore, the processor unit can be configured to read the distance to which the second discharge curve belongs from the data memory. A corresponding situation can be set for the first discharge curve. Therefore, the first processor unit can be configured to read the distance to which the first discharge curve belongs from the data memory. Ideally, the sum of the two read distances yields a predetermined sensor distance between the two sensors. Thus, the first sensor distance, i.e., the distance between the actual location of partial discharge on the cable segment (partial discharge location) and the first sensor, is determined by the distance to which the first partial discharge curve belongs. However, the first sensor distance is also determined by subtracting the distance to which the second discharge curve belongs from the predetermined sensor distance. In this case, the processor unit can be configured to redundantly determine the first sensor distance based on the predetermined sensor distance, the distance to which the first discharge curve belongs, and the distance to which the second discharge curve belongs. This is because the processor unit can be configured to perform the above mathematical steps. If the difference between the predetermined sensor distance and the distance to which the second discharge curve belongs does not correspond to the distance to which the first discharge curve belongs, the first sensor distance can be determined, for example, by averaging the aforementioned difference and the distance to which the first discharge curve belongs. The processor unit can be configured accordingly. The distance to the first sensor can also be determined more accurately by considering the distances belonging to the first and second discharge curves.

[0019] Another advantageous embodiment of the system is characterized by having a first pulse feeding unit for feeding at least one first electrical pulse into a cable segment. The processor unit is configured to change parameters of the cable model, which represents the transmission characteristics of the electrical pulse on the cable segment. The processor unit is also configured to control the first pulse feeding unit such that an electrical pulse, referred to as a first reference pulse, is fed into the cable segment via the first pulse feeding unit. The first pulse feeding unit is arranged spaced apart from a first sensor, which is configured to detect an electrical signal, referred to as a first reference signal, caused by the first reference pulse. Furthermore, the first sensor is configured to transmit a first test signal, representing the first reference signal, directly or indirectly to the processor unit. Additionally, the processor unit is configured to adapt the parameters of the cable model based on the first test signal such that the transmission characteristics represented by the cable model correspond to the actual transmission characteristics of the cable segment represented by the first reference pulse and the first reference signal.

[0020] As already described regarding the system, the data memory can store a set of curves formed by multiple first curves, wherein each of these first curves in the first curve set can be predetermined using a cable model of the cable segment. The cable model can, for example, be stored in the system's data memory. Furthermore, the cable model can, for example, be loaded by a processor unit to implement the cable model. The cable model can be changed by parameters. By changing the parameters of the cable model, the transmission characteristics of the modeled electrical pulses on the cable segment can be altered. For example, the parameters of the cable model can be adapted to model additional attenuation characteristics and / or dispersion characteristics of the cable segment using the cable model. For example, these parameters can be used to induce frequency-specific attenuation and / or location-specific attenuation and / or frequency-specific dispersion and / or location-specific dispersion. By configuring the processor unit to change the parameters of the cable model, the transmission characteristics of the cable segment can be adapted particularly precisely to the actual transmission characteristics of the cable segment. For the first use of the cable model, predetermined parameters can be used. However, to adapt the parameters of the cable model to the actual transmission characteristics and thereby achieve accurate modeling, test signals are advantageous.

[0021] Therefore, the processor unit is configured to control a first pulse feed unit, such that an electrical pulse, referred to as a first reference pulse, is fed into the cable segment via the first pulse feed unit. Preferably, this feeding is performed at a distance from the first sensor. This distance between the first pulse feed unit and the first sensor can be predetermined and / or known. As previously mentioned, the first sensor detects an electrical signal. Therefore, the first sensor also detects an electrical signal, referred to as a first reference signal, caused by the first reference pulse. Furthermore, the first sensor is configured to transmit a test signal to the processor unit, wherein the first test signal represents the first reference signal. Typically, the first reference signal is an analog signal. To avoid degrading the information content, the first sensor can be configured to digitize the first reference signal, thereby forming the first test signal. Furthermore, the first sensor is configured to transmit the first test signal to the processor unit.

[0022] Furthermore, the processor unit can be coupled to the pulse feed unit to send a control signal to the first pulse feed unit, causing a first reference pulse to be fed into the cable segment. The control signal can represent the first reference pulse. Alternatively or supplementarily, the processor unit can at least temporarily store data representing the first reference pulse. Alternatively or supplementarily, a signal representing the first reference pulse can be sent from the pulse feed unit to the processor unit after the first reference pulse is fed in, wherein the signal represents the first reference pulse.

[0023] A first reference signal is generated by the feeding of a first reference pulse, which is detected by a first sensor. Therefore, the processor unit can be configured to determine the actual transmission characteristics of the cable segment based on the first reference pulse and the first reference signal. Since the location where the pulse feeding unit feeds the first reference pulse into the cable segment is known, the cable model can also be used to model the transmission characteristics represented by the cable model, which occur when a pulse corresponding to the first reference pulse is fed into the cable segment modeled by the cable model at the theoretically same location. Therefore, in this context, the processor unit is configured to adapt the parameters of the cable model based on a first test signal, such that the transmission characteristics represented by the cable model correspond to the actual transmission characteristics of the cable segment represented by the first reference pulse and the first reference signal. This applies at least when the cable segment is modeled by the processor unit using the cable model such that a pulse corresponding to the first reference pulse is fed into the modeled cable segment, thereby generating an auxiliary signal corresponding to the first reference signal using the cable model. This is because these auxiliary signals and the aforementioned pulse allow the transmission characteristics represented by the cable model to be compared with the actual transmission characteristics of the cable segment in a corresponding manner. Here, the parameters of the cable model are adapted in such a way that the difference between the transmission characteristics represented by the cable model and the actual transmission characteristics of the cable segment is minimized. Preferably, this difference relates to amplitude characteristics and / or frequency characteristics.

[0024] By adapting the parameters of the cable model, the cable model can be adapted to the actual conditions of the cable segment very easily. This is especially suitable for initial commissioning. However, it is also possible to adapt the cable model multiple times during operation by changing the parameters. Therefore, in practice, it may occur that strong partial discharge causes changes in attenuation and / or dispersion at specific locations in the cable segment. This attenuation and / or dispersion may change, particularly in terms of amplitude characteristics or frequency characteristics. These changes can be taken into account by adapting the parameters of the cable model. If the re-adaptation of the cable model parameters is implemented using a processor unit, the processor unit can be configured to redetermine the first curve set and / or the second curve set. Furthermore, the processor unit can be configured to store the new first curve set in the data memory. The corresponding situation can be applied to the new second curve set and distance. It is also possible, therefore, to determine the first sensor distance with particular accuracy during continuous operation, and more precisely, especially even when the cable segment undergoes changes.

[0025] The parameters of a cable model can affect transmission characteristics such as amplitude characteristics, phase characteristics, group delay, phase delay, relative permittivity of the cable segment, and / or other characteristics of the cable segment. This allows the cable model to be adapted to actual cable segments with exceptional precision.

[0026] It has proven advantageous that the first sensor is located at one end of the cable segment and the first pulse feeding unit feeds the first reference pulse at the opposite end of the cable segment. This is because, in this case, the first reference pulse must be transmitted through the entire line segment before the corresponding first reference signal caused by the first reference pulse is detected by the first sensor. Therefore, this first reference signal is particularly advantageously suited to adapting the parameters of the cable model.

[0027] As previously described, it is preferable that the system has two sensors, namely a first sensor and a second sensor. Furthermore, it is preferable that the first sensor is disposed at one end of the cable segment and the second sensor is disposed at the opposite end of the cable segment. At this opposite end, a first reference pulse is preferably fed in as previously described.

[0028] An advantageous embodiment of the system is characterized by having a second pulse feeding unit for feeding at least one second electrical pulse into a cable segment. The processor unit is configured to control the second pulse feeding unit such that an electrical pulse, referred to as a second reference pulse, is fed into the cable segment via the second pulse feeding unit, wherein the second pulse feeding unit is arranged spaced apart from a second sensor. The second sensor is configured to detect an electrical signal, referred to as a second reference signal, caused by the second reference pulse. Furthermore, the second sensor is configured to transmit a second test signal, representing the second reference signal, directly or indirectly to the processor unit. The processor unit is configured to adapt parameters of the cable model based on the first test signal and the second test signal, such that the transmission characteristics represented by the cable model correspond to the actual transmission characteristics of the cable segment represented by the first reference pulse and the first reference signal and / or by the second reference pulse and the second reference signal.

[0029] The second pulse feed unit, second reference pulse, second reference signal, and second test signal are described with reference to the foregoing description, preferred features, technical effects, and / or advantages in a similar manner to those described in conjunction with the first pulse feed unit, first reference pulse, first reference signal, and first test signal. However, it should be noted that the second pulse feed unit is arranged spaced apart from the second sensor. For example, the second pulse feed unit can be arranged such that it feeds the second reference pulse at the same end where the first sensor is also arranged. The second sensor is preferably arranged at the opposite end of the cable segment, where the first pulse feed unit preferably also feeds the first reference pulse. Therefore, the reference pulse fed by the second pulse feed unit must be transmitted from the cable segment to the second sensor at the opposite end, where it is detected as the second reference signal. However, during transmission, the fed reference pulse undergoes frequency-dependent and / or amplitude-dependent attenuation and / or dispersion.

[0030] In principle, the second test signal can be used in a similar manner to the first test signal to adapt to the parameters of the cable model. However, if this adaptation is based on both the first and second test signals, the parameters of the cable model can be adapted more precisely. This adaptation can be implemented by a processor unit such that the transmission characteristics represented by the cable model correspond to the actual transmission characteristics of the cable segment represented by the first reference pulse and the first reference signal, and to the actual transmission characteristics of the cable segment represented by the second reference pulse and the second reference signal. Through this correspondingly precise adaptation of the cable model parameters, as previously described, the first and / or second curve sets preferably stored in the data memory can be updated. This, in turn, allows for a particularly precise determination of the first sensor distance.

[0031] An advantageous embodiment of the system is characterized in that the first sensor and the second pulse feed unit are configured as a common first converter unit. The first converter unit can be configured to be arranged and / or secured to an end of the cable segment. A further embodiment of the system is characterized in that the second sensor and the first pulse feed unit are configured as a common second converter unit. The second converter unit can be configured to be arranged and / or secured to another end of the cable segment. Therefore, the first and second converter units can be arranged and / or secured to opposite ends of the cable segment.

[0032] Another advantageous embodiment of the system is characterized in that the processor unit is configured such that the first and / or second pulse feeding unit is periodically configured to feed reference pulses and adapt the parameters of the cable model after each reference pulse feeding.

[0033] Periodically feeding in reference pulses, preferably periodically feeding in a first reference pulse and / or periodically feeding in a second reference pulse, allows for periodic updates to the cable model. This also allows for periodic updates to the first and / or second curve sets. The corresponding conditions apply to the respective distances. Therefore, the processor unit can be configured accordingly. By periodically updating the cable model and / or one or more curve sets, particularly accurate and timely detection of the first sensor distance can be achieved.

[0034] Another advantageous embodiment of the system is characterized in that the first sensor is configured to periodically detect electrical signals in the cable segment. The processor unit is also preferably configured to determine a first discharge curve in any case where the electrical signal detected by the first sensor forms a first discharge signal, and to determine the distance from the first sensor to the corresponding partial discharge based on the first discharge curve.

[0035] Therefore, it is preferable to stipulate that the first sensor distance is determined in an event-controlled manner, that is, always when the electrical signal detected by the first sensor generates a first discharge signal. This allows the first sensor distance to be determined each time a partial discharge is detected on the cable segment.

[0036] Another advantageous embodiment of the system is characterized in that the second sensor is configured to periodically detect electrical signals in the cable segment. The processor unit is also preferably configured to determine the corresponding second discharge curve in any case where the electrical signal detected by the second sensor forms a second discharge signal, and to determine the first sensor distance between each partial discharge and the first sensor based on a predetermined sensor distance, the distance to which the first discharge curve belongs, and the distance to which the second discharge curve belongs. To determine the first sensor distance, it has been previously determined that when the system has both first and second sensors, the first sensor distance can be determined with particular precision when using the distance to which the first discharge curve belongs, the distance to which the second discharge curve belongs, and the predetermined sensor distance between the two sensors. Therefore, this first sensor distance can also be determined in an event-controlled manner, i.e., in any case where the electrical signal detected by the first and second sensors forms the corresponding discharge signal.

[0037] Another advantageous embodiment of the system is characterized in that the processor unit is configured to determine the frequencies of a plurality of actual partial discharges at the same distance relative to the first sensor, and the output signal also represents the frequencies.

[0038] By configuring the processor unit to determine the first and / or second discharge curves, weak partial discharges can also be detected and considered, and the first sensor distance can be calculated separately for this purpose. If multiple weak partial discharges occur at the same location and therefore at the same distance from the first sensor, this in practice will result in the multiple weak partial discharges causing adverse effects on the cable segment similar to a single, particularly strong partial discharge. Therefore, the frequency of multiple actual partial discharges occurring on the cable segment at the same distance from the first sensor is particularly important information in practice. Thus, transmitting the frequency of such partial discharges by means of an output signal advantageously provides the possibility of accurately monitoring the condition of the cable segment.

[0039] Another advantageous embodiment of the system is characterized in that the processor unit is configured to obtain at least one characteristic parameter of a plurality of actual partial discharges at the same distance relative to the first sensor, and the output signal further represents the obtained characteristic parameter.

[0040] Characteristic parameters can represent the properties of partial discharge. Therefore, characteristic parameters can, for example, represent the energy of a partial discharge. However, the energy of a partial discharge may only be one piece of information among many, which can be obtained from the spectral composition of the partial discharge. A processor unit can be configured to perform source filtering separation to obtain the characteristic parameters.

[0041] Another advantageous embodiment of the system is characterized in that the processor unit is configured to generate an alarm signal when the frequency of partial discharge is greater than a predetermined threshold frequency and / or when the obtained characteristic parameter of partial discharge is greater than a predetermined threshold characteristic parameter, and the signal interface is configured to transmit the alarm signal.

[0042] As previously explained, the frequency of partial discharges occurring at the same distance as the first sensor can lead to damage to the cable segment. The frequency of these partial discharges can be a measure of the extent of damage. Therefore, it is advantageous to generate an alarm signal when the frequency exceeds a predetermined threshold frequency. This threshold frequency can be predetermined such that an alarm signal is generated promptly before the damage to the cable segment becomes excessive. A similar approach can be taken when the characteristic parameter exceeds a predetermined threshold characteristic parameter. In this case, there is also a risk of damage to the cable segment, thus generating a corresponding alarm signal.

[0043] Another advantageous embodiment of the system is characterized in that the processor unit is configured to determine the aging state of the cable segment based on the frequency of partial discharge and / or the characteristic parameters of the at least one determined partial discharge and / or the adapted parameters, wherein the output signal further represents the aging state.

[0044] The aging condition of a cable segment can be determined based on the number and / or size of damaged sections. The processor unit can be configured accordingly for this determination. A higher frequency of partial discharges indicates increased aging. The corresponding conditions can be determined based on characteristic parameters. The processor unit can also be configured to adapt the parameters of the cable model based on the aging condition.

[0045] Another advantageous embodiment of the system is characterized in that the cable segment has multiple cable segments arranged sequentially along the cable segment, wherein the end-to-end opposite ends of the cable segments are connected to each other to form a coupling point. Each cable segment is equipped with a first sensor and a first set of curves for the corresponding first sensor, such that the system has multiple first sensors and multiple first sets of curves are stored in the data memory. The processor unit is preferably configured to identify cable segments with partial discharge as identified cable segments based on the distance of the first sensor. The signal interface is preferably configured to provide an output signal indicating the identified cable segment and the distance of the first sensor to the partial discharge of the identified cable element.

[0046] In practice, partial discharge may occur in one cable segment. However, the cable segment where partial discharge occurs is coupled to other cable segments. Therefore, the partial discharge causes an electrical pulse that propagates along all cable segments and is thus detected by all first sensors. To prevent the accidental assumption that partial discharge occurs in every cable segment, the cable segment with actual partial discharge is determined as the identified cable segment based on the first sensor distance using a processor unit. The remaining first sensor distances are discarded. Furthermore, it is preferably specified that the output signal provided by the signal interface indicates the identified cable segment and represents the first sensor distance to the identified cable segment. This allows for a particularly accurate and explicit determination of the first sensor distance and, therefore, also a precise determination of the location of partial discharge along the entire cable segment. The processor unit can be configured accordingly.

[0047] According to a second aspect of the invention, the task described at the outset is solved by a transmission system according to the invention. Therefore, a transmission system for transmitting electrical energy is provided, wherein the transmission system has cable segments and a system. Here, the system is an embodiment of one of the advantageous embodiments according to the first aspect of the invention and / or its related embodiments. Regarding the system, reference is made to the preceding description, preferred features, technical effects, and / or advantages in a manner similar to that already set forth with respect to one of the advantageous embodiments of the first aspect of the invention or its related embodiments.

[0048] According to a third aspect of the invention, the task described at the beginning is solved by a method according to the invention. Therefore, a method is proposed for operating a system for transmitting electrical energy in a cable segment, wherein the system has a first sensor for detecting electrical signals in the cable segment, a processor unit, a data memory, and a signal interface. The data memory stores a first set of curves consisting of a plurality of first curves, each carrying a corresponding distance to the first sensor. Each first curve represents a predetermined pulse response of an electrical pulse via a cable model of the cable segment, the electrical pulse being caused by a modeled partial discharge on the cable segment at a distance to the first sensor corresponding to the respective first curve. Furthermore, the method includes the following steps a) to e): In step a), electrical energy is transmitted via the cable segment. In step b), an electrical signal, referred to as a first discharge signal, is detected by the first sensor and is caused by an actual partial discharge on the cable segment. In step c), a first measurement signal, representing the first discharge signal, is transmitted directly or indirectly from the first sensor to the processor unit. In step d), based on the first measurement signal and with the aid of the processor unit, a first curve in the first curve set is determined to be a first discharge curve, wherein the first discharge curve is optimally correlated with the first discharge signal in the first curve set. In step e), the processor unit determines the actual partial discharge and the first sensor distance of the first sensor based on the distance to which the first discharge curve belongs.

[0049] The steps of this method correspond to the features of the system according to the first aspect of the invention. Therefore, for the method according to the third aspect of the invention, reference is made to advantageous descriptions, preferred features, technical effects, and / or advantages in a manner similar to that already described with respect to the system according to the first aspect of the invention. Therefore, repetition is omitted.

[0050] Furthermore, advantageous embodiments of the method described below are illustrated with reference to preferred features, technical effects, and advantages in a manner similar to those already described for corresponding advantageous embodiments of the system. Similar repetitions are omitted here.

[0051] An advantageous embodiment of the method is characterized in that the system has a second sensor for detecting electrical signals on a cable segment, wherein the data memory stores a set of second curves consisting of a plurality of second curves, each carrying a distance to the corresponding second sensor. Each second curve represents a predetermined pulse response of an electrical pulse via a cable model of the cable segment, the electrical pulse being caused by a modeled partial discharge on the cable segment at a distance to the second sensor corresponding to the respective second curve. The first and second sensors are arranged relative to each other on the cable segment at predetermined sensor distances. Furthermore, the method includes additional steps d.1) to d.3): In step d.1), an electrical signal, referred to as a second discharge signal, is detected by the second sensor and is caused by the same actual partial discharge on the cable segment. In step d.2), a second measurement signal, representing the second discharge signal, is transmitted directly or indirectly from the second sensor to a processor unit. In step d.3), based on the second measurement signal and by means of the processor unit, a second curve in the set of second curves is determined to be the second discharge curve, which is optimally correlated with the second discharge signal among the second curves in the set of second curves. In step e), the distance to the first sensor is additionally determined by the processor unit based on the distance to which the second discharge curve belongs.

[0052] Another advantageous embodiment of the method is characterized in that the system has a first pulse feeding unit for feeding at least one first electrical pulse into a cable segment. The processor unit is configured to change parameters of the cable model, which represents the transmission characteristics of the electrical pulse on the cable segment, and the first pulse feeding unit is arranged spaced apart from the first sensor. Furthermore, the method includes the following steps f) to i): In step f), the processor unit controls the first pulse feeding unit to feed an electrical pulse, referred to as a first reference pulse, into the cable segment. In step g), the first sensor detects electrical signals, referred to as first reference signals, respectively caused by the first reference pulse in the first reference pulse. In step h), first test signals are transmitted directly or indirectly from the first sensor to the processor unit, the first test signals representing one of the first reference signals. In step i), the parameters of the cable model are adapted by means of the processor unit and based on the at least one first test signal, such that the transmission characteristics represented by the cable model correspond to the actual transmission characteristics of the cable segment represented by the first reference pulse and the first reference signal.

[0053] Another advantageous embodiment of the method is characterized in that the system has a second pulse feeding unit for feeding at least one second electrical pulse into the cable segment, wherein the second pulse feeding unit is arranged spaced apart from the second sensor. Furthermore, the method includes the following steps j) to l): In step j), the second pulse feeding unit is controlled by a processor unit to feed an electrical pulse, referred to as a second reference pulse, into the cable segment. In step k), an electrical signal, referred to as a second reference signal and caused by the second reference pulse, is detected by the second sensor. In step l), a second test signal, representing the second reference signal, is transmitted directly or indirectly from the second sensor to the processor unit. Furthermore, in step j), the parameters of the cable model are adapted by the processor unit based on the first and second test signals such that the transmission characteristics represented by the cable model correspond to the actual transmission characteristics of the cable segment represented by the first and second reference pulses and / or by the second and second reference pulses.

[0054] Another advantageous embodiment of the method is characterized by having an additional step m): in step m), an output signal is transmitted via a signal interface, the output signal representing the distance of the first sensor.

[0055] Another advantageous embodiment of the method is characterized in that the group of method steps a) to e) is performed once or repeatedly.

[0056] Another advantageous embodiment of the method is characterized in that steps g) to j) or steps g) to m) are performed once, periodically, after or before each set of steps a) to e).

[0057] Another advantageous embodiment of the method is characterized in that the first and / or second curve sets are calculated by means of the processor unit using a cable model updated by the adapted parameters and preferably stored in the data memory after each adaptation of the parameters of the cable model.

[0058] Further features, advantages, and applications of the invention will become apparent from the following description and accompanying drawings of the embodiments. Herein, all described and / or illustrated features, in themselves and in any combination, form the subject matter of the invention. Furthermore, the same reference numerals in the drawings denote the same or similar objects. Attached Figure Description

[0059] Figure 1 A first advantageous implementation of the system is illustrated in a schematic diagram.

[0060] Figure 2Multiple curves that share a common set of curves are shown.

[0061] Figure 3 Another advantageous implementation of the system is illustrated in the diagram.

[0062] Figure 4 Another advantageous implementation of the system is illustrated in the diagram.

[0063] Figure 5 Another advantageous implementation of the system is illustrated in the diagram.

[0064] Figures 6 to 8 Advantageous flowcharts for this method are shown separately. Detailed Implementation

[0065] exist Figure 1 An advantageous embodiment of system 2 is schematically illustrated. System 2 includes a first sensor 6, a processor unit 8, a data storage 10, and a signal interface 12. The first sensor 6 is configured to detect electrical signals in cable segment 4. Therefore, system 2 is also used for cable segment 4, which is used to transmit electrical energy.

[0066] In principle, the first sensor 6 can be configured as a single sensor 6 or as an integrated component of another device. Therefore, for example, in practice, a high-frequency converter is often fastened to the end of a cable segment, where the first sensor 6 can be part of such a high-frequency converter.

[0067] Cable segment 4 may also be constructed and / or referred to as a cable. Cable segment 4 typically has a conductive core, for example, made of copper, and an insulating portion covering the core. If an electrical signal is transmitted through the conductive core, the first sensor 6 may, for example, be configured to detect the electrical signal without contact. Alternatively, however, the sensor 6 may also have electrical contact with the conductive core of cable segment 4, such that the first sensor 6 is configured to detect the electrical signal of cable segment 4 through this electrical contact.

[0068] The first sensor 6 is preferably coupled to the processor unit 8 via signal connection 58. The processor unit 8 can also be coupled to the data memory 10 via another signal connection 60 to read data from or store data in the data memory 10. Furthermore, it is preferably specified that the processor unit 8 is connected to the signal interface 12 via another signal connection 62. The signal interface 12 is used to transmit the output signal U. The processor unit 8 can, for example, control the signal interface 12 via another signal line 62 to send the output signal U. The signal interface 12 can form an integrated part of the processor unit 8. Therefore, the processor unit 8 and the signal interface 12 can form a common unit. Furthermore, it is possible that the data memory 10 is allocated to this common unit. In other words, a common unit including the processor unit 8, the data memory 10, and the signal interface 12 can be provided.

[0069] When electrical energy is transmitted via cable segment 4, especially when the electrical energy is transmitted at particularly high voltages, partial discharge 22 occurs. Partial discharge 22 can occur at partial discharge point T. Partial discharge 22 causes pulse 20, which extends in the opposite direction along the axial direction L of cable segment 4. If the partial discharge point T is separated from the first sensor 6 by a first sensor distance E, a certain propagation time is required for pulse 20 to travel from partial discharge point T to the first sensor 6. However, the application of using the propagation time to determine the partial discharge point T has proven to be error-prone in practice. The pulse 20 caused by partial discharge 22 is purely exemplary in... Figure 2 As shown in the diagram. Here, the amplitude A of pulse 20 is designated as 1. Due to the physical characteristics of cable segment 4, pulse 20 undergoes location-dependent and / or frequency-dependent attenuation and / or dispersion. (As shown in...) Figure 2 As illustrated, the signal shape changes according to the first sensor distance E between the partial discharge location T and the first sensor 6.

[0070] If we assume, purely by example, that the length of cable segment 4 is approximately 800 m, then the variation of pulse 20 depends on the route traversed or on the distance E from the first sensor. Figure 2 As shown in the diagram. If a partial discharge T occurs, for example, at a distance E from the first sensor 6, 100 m away, then the first sensor 6 can detect at least the electrical signal corresponding to curve 16, which is shown in the diagram. Figure 2The partial discharge 22 is plotted at a first sensor distance E of 100 m. If the partial discharge 22 occurs at a more distant partial discharge location T, for example, 200 m away from the first sensor 6, then the first sensor distance E is 200 m. In this case, the sensor 6 is able to detect the electrical signal corresponding to curve 16 at the first sensor distance E of 200 m. In other words, the electrical signal detected in this case has the shape of curve 16 at the first sensor distance E of 200 m, except for a proportional factor. Figure 2 The other curve 16 in the figure is generated at a first sensor distance E of 300 m, 400 m or 500 m in the case of partial discharge 22.

[0071] from Figure 2 As can be seen, curve 16 differs in its frequency characteristics and amplitude characteristics depending on the first sensor distance E. Therefore, the first sensor distance E can also be determined independently of the propagation time of the first pulse 20 based on the curve shape of the signal measured by the first sensor 6. To achieve this, a first curve set 14 consisting of a plurality of first curves 16 is stored in the data memory 10, each first curve carrying its corresponding distance to the first sensor 6, wherein each first curve 16 represents a predetermined pulse response of the electrical pulse 20 by means of a cable model of the cable segment 4, the electrical pulse being caused by a modeled partial discharge 22 on the cable segment 4 at the distance to the first sensor 6 corresponding to the respective first curve 16.

[0072] The advantage of using the cable model of cable segment 4 is that cable segment 4 does not need to be partially damaged by partial discharge 22 to obtain information about the first curve 16. More precisely, a pulse 20 can be induced at any location on the modeled cable segment 4 using the cable model, and the first curve 16 can be obtained using the same cable model. This first curve will be measured at the corresponding distance between the pulse acting on the modeled cable segment 4 and the location of the first sensor 6. Therefore, by changing the distance from the location of the sensor 6, multiple first curves 16 can be predetermined using the cable model. For this purpose, processor unit 8 can be configured. These first curves 16 collectively form a first curve set 14. This curve set 14 is stored in data memory 10. Here, data representing the first curve set 14 or the first curve 16 can actually be stored in data memory 10. A similar situation applies to the corresponding distances.

[0073] Then, the first curve 16 of the first curve set 14 can be compared with the electrical signal of the first sensor 6, which is arranged on the actual cable segment 4 for detecting the electrical signal. Here, the curve 16 that best correlates with or is consistent with the electrical signal actually detected by the first sensor 6 can be determined. Furthermore, the distance to which each first curve 16 belongs is stored in the data memory 10. Therefore, if one of the curves 16 is determined to be the first discharge curve 26, which best correlates with the discharge signal 24 actually detected by the sensor 6 among the first curves 16 in the first curve set 14, the distance to which the first discharge curve 26 belongs, for example, the first sensor distance E of 300 m, can be determined by means of the first curve 16 stored in the data memory 10 and the distance to which it belongs.

[0074] Therefore, for System 2, the first sensor 6 is configured to detect an electrical signal, referred to as the first discharge signal 24, caused by an actual partial discharge 22 on the cable segment 4. However, this first discharge signal 24 is typically an analog signal. Therefore, the first sensor 6 is preferably configured to digitize the first discharge signal 24 in order to determine a first measurement signal M, representing the first discharge signal 24, based on this. The first sensor 6 can then transmit the first measurement signal M to the processor unit 8, for example, via a signal connection 58. The signal connection can be configured as a wired signal connection 58 or a wireless signal connection 58. However, it is also possible that an optical signal connection exists between the first sensor 6 and the processor unit 8, through which the first measurement signal M can be transmitted from the first sensor 6 to the processor unit 8.

[0075] The processor unit 8 is configured to determine, based on the first measurement signal M, one of the first curves 16 in the first curve set 14 as a first discharge curve 26, wherein the first curve best matches the first discharge signal 24 among the first curves 16 in the first curve set 14. Which of the first curves 16 best matches the first discharge signal 24 can be determined based on the cross-correlation between the first discharge signal 24 and the corresponding first curve 16. The first curve 16 that causes the maximum correlation value can be understood as best matching the first discharge signal 24. Then, the corresponding first curve 16 forms the first discharge curve 26. The distance to which the first discharge curve 26 belongs is stored in the data memory 10. The processor unit 8 is coupled to the data memory 10 via a signal connection 60, such that the processor unit 8 can read the corresponding distance to the first discharge curve 26 from the data memory 10. Therefore, the processor unit 8 is configured to determine the first sensor distance E from the actual partial discharge 22 to the first sensor 6 based on the distance to which the first discharge curve 26 belongs. In the simplest case, the distance E from the first sensor corresponds to the distance of the first discharge curve 26, and this distance is stored in the data memory 10. Figure 1 and Figure 2 In the case shown, the distance relative to the first discharge curve 26 stored in the data memory 10 is 300 m. Therefore, in this case, the distance E of the first sensor can be determined to be 300 m.

[0076] To provide information about a first sensor distance E of 300 m, system 2 has a signal interface 12 implemented for transmitting an output signal U representing the first sensor distance E. Thus, the information about the first sensor distance E can be used in other components, devices, and / or modules of system 2.

[0077] exist Figure 3 Another advantageous implementation of system 2 is schematically illustrated. Regarding... Figure 3 System 2 in the middle, refers to the same way as the system in the middle. Figure 1 The system described earlier. However, Figure 3 System 2 has an additional sensor 28, namely a second sensor 28. The first and second sensors 6, 28 can be arranged and / or fastened to opposite ends 42, 44 of the cable segment 4. The second sensor 28 is preferably constructed similarly to the first sensor 6. Therefore, reference is made to the advantageous description, preferred features, technical effects and / or advantages of the second sensor 28, as has been previously described with respect to the first sensor 6.

[0078] The second sensor 28 is preferably coupled to the processor unit 8 via a separate signal connection 64, so that the second measurement signal N can be transmitted from the second sensor 28 to the processor unit 8.

[0079] If a partial discharge 22 occurs on cable segment 4, the resulting pulse 20 is detected as an electrical signal on the first sensor 6 and as a separate electrical signal on sensor 28. However, these two detected electrical signals are different because the first sensor distance E does not correspond to the second sensor distance F. Different attenuations and / or dispersions occur at different distances E and F, resulting in the detection of a first discharge signal 24 by the first sensor 6 and a second discharge signal by the second sensor 28. If the total length of cable segment 4 is, for example, 800 m, the first discharge signal 24 can be transmitted to the processor unit 8 via a first measurement signal M. The first processor unit 8 can read the corresponding 300 m distance E of the first curve 16 from the data memory 10 based on the first discharge signal 24. The data memory 10 can store an additional set of curves, namely a set of multiple second curves, each with a corresponding distance to the second sensor 28. Each second curve represents a predetermined pulse response of an electrical pulse via a cable model of cable segment 4, caused by a modeled partial discharge on cable segment 4 at the distance to the second sensor 28 corresponding to the respective second curve. After transmitting a second measurement signal N representing a second discharge signal to the processor unit 8, the processor unit 8 can determine one of the second curves in the set of second curves as the second discharge curve, which best corresponds to the second discharge signal among all the second curves. This second curve, referred to as the second discharge curve, is stored in the data memory 10 along with its corresponding distance. Therefore, the processor unit 8 can read the corresponding distance from the data memory 10. For this purpose, the processor unit 8 is preferably configured. The corresponding second sensor distance F can be, for example, 500 m. If the two sensors 6 and 28 are arranged at a sensor distance S of 800 m, then the previously calculated sensor distances, namely the first sensor distance E of 300 m and the second sensor distance F of 500 m, are consistent with the 800 m sensor distance S between the two sensors 6 and 28. Therefore, the processor unit 8 is preferably configured to determine the actual partial discharge 22 and the first sensor distance E of the first sensor 6 based on the predetermined sensor distance S (800 m), the distance to which the first discharge curve 26 belongs (300 m), and the distance to which the second discharge curve belongs (500 m). In the example described above, the first sensor distance E can be determined as redundant. However, if the distances E and F are not obtained by adding them together to obtain the sensor distance S, it can be determined by averaging the distance to which the first discharge curve belongs and the difference formed by the sensor distance and the distance to which the second discharge curve belongs. Thus, the first sensor distance E can be determined with particular precision. The first sensor distance E and the known location for the first sensor 6 are also known, as is the location of the partial discharge T.

[0080] exist Figure 4 Another advantageous implementation of system 2 is shown. Here, system 2 is at least substantially corresponding to [the specific implementation of system 2]. Figure 4 System 2 is described. Therefore, the corresponding description is referenced in a similar manner. Furthermore, Figure 4 System 2 has a first pulse feed unit 32. This first pulse feed unit can be constructed together with the second sensor 28. The first pulse feed unit 32 and the second sensor 28 can therefore form a common unit.

[0081] In principle, the parameters of the cable model can be predetermined. Thus, for example, the parameters of the cable model can be predetermined such that the cable model can use these parameters to determine a first and / or second set of curves for multiple structurally identical cable segments 4. However, in practice, cable segments vary from one another, ranging from small to large. Therefore, the same set of parameters for cable models used for multiple cable segments typically only allows for suboptimal modeling. To achieve better adaptation of the parameters to each cable segment and thus better modeling of the cable segments through the cable model, it is preferable to specify that the parameters of the cable model are adapted to the actual characteristics of each cable segment 4. This can be done during the first run of the cable segment. However, alternatively or additionally, the parameters of the cable model can be adapted periodically or according to specific events. By repeatedly adapting the parameters of the cable model during operation, better modeling of the cable segment 4 can be ensured by the adapted parameters of the cable model, which may also be subject to certain changes during operation. If, for example, a strong partial discharge occurs on the cable segment 4, causing a change in the attenuation and / or dispersion characteristics of the cable segment 4, this can be better described by adapting the parameters of the cable model.

[0082] Therefore, it is preferred that the system has a first pulse feeding unit 32 configured to feed at least one first electrical pulse into the cable segment 4. Here, the processor unit 8 is configured to control the first pulse feeding unit 32 such that an electrical pulse, referred to as a first reference pulse 38, is fed into the cable segment 4 via the first pulse feeding unit 32. The first pulse feeding unit 32 is arranged at a distance from the first sensor 6. Preferably, the first sensor 6 is arranged at the first end 42 of the cable segment 4, while the first pulse feeding unit 32 is arranged at the opposite end 44 of the cable segment 4. This ensures that the first reference pulse 38 fed into the cable segment 4 must pass through the entire cable segment 4 before it can be detected by the first sensor 6 as an electrical signal. Therefore, the first sensor 6 is configured to detect the electrical signal referred to as the first reference signal and caused by the first reference pulse 38. If the first reference pulse 38 is fed into the cable segment 4 by the first pulse feeding unit 32, the first reference pulse 38 is subjected to attenuation and / or dispersion caused by the cable segment 4. Therefore, the first reference signal detected by the first sensor 6 is caused by a first reference pulse. In particular, the first reference signal can be a first reference pulse 38 attenuated by cable segment 4. The first reference signal is typically an analog signal. Therefore, the first sensor 6 is preferably configured to digitize each first reference signal. Furthermore, the first sensor 6 is configured to transmit a first test signal O to the processor unit 8 via signal connection 58, wherein the first test signal O represents the first reference signal.

[0083] Preferably, the processor unit 8 is coupled to the first pulse feed unit 32 via control line 66 to control the first pulse feed unit 32. Therefore, the first reference pulse 38 is also known to the processor unit 8. If the second sensor 28 and the first pulse feed unit 32 constitute a common unit, then for control purposes, the first reference pulse 38 can be detected by the second sensor 28, and the corresponding signal can be transmitted to the processor unit 8 via signal line 64. Thus, the first reference pulse 38 is also known to the processor unit 8. Furthermore, the processor unit 8 knows the at least one first reference signal via the first test signal O from the first sensor 6 to the processor unit 8. Therefore, the transmission characteristics of the cable segment 4 can be determined in a conventional manner from the first reference pulse 38 fed into the cable segment 4 and the associated first reference signal. The processor unit 8 can be constructed accordingly. In principle, the same transmission characteristics should be achievable using a cable model. However, when cable segment 4 is first put into operation and / or due to changes in cable segment 4, it may be necessary to adapt the parameters of the cable model so that the transmission characteristics of cable segment 4 represented by the cable model are consistent with the actual transmission characteristics of cable segment 4, which can be determined from the first reference pulse and the associated first reference signal.

[0084] Therefore, the processor unit 4 is configured to adapt the parameters of the cable model based on the first test signal O, such that the transmission characteristics of the cable segment 4 represented by the cable model correspond to the actual transmission characteristics of the cable segment 4 represented by the first reference pulse and the first reference signal.

[0085] System 2 may also include a second pulse feed unit 40, which is also configured to feed electrical pulses into cable segment 4. The second pulse feed unit 40 is capable of feeding a corresponding second reference pulse into cable segment 4, allowing the first sensor 6 to detect a second reference signal. The second pulse feed unit 40 can be used and operated together with the first sensor 6 in a manner similar to that described above for the first pulse feed unit 32 and the second sensor 28. Therefore, for example, it is possible that the two pulse feed units 32, 40 feed reference pulses into cable segment 4 in parallel, at staggered times, or alternately, and the corresponding reference signals are detected by sensors 6, 28. The reference pulses and reference signals can then be used to better determine the actual transmission characteristics of cable segment 4. Furthermore, the second pulse feed unit 40 can be constructed together with the first sensor 6. They can therefore form a common unit.

[0086] exist Figure 5 Another advantageous embodiment of System 2 is shown below. The processor unit 8, data memory 10, and signal interface 12 are similarly described previously. However, System 2 is adapted to a cable segment 4 having a plurality of cable segments 46 arranged sequentially along the front and back of the cable segment 4, wherein the end portions 44, 42 of the cable segments 46 opposite each other at their ends are connected to each other to form a coupling portion 48. Here, the coupling portion 48 is configured such that electrical energy can be transferred from cable segment 46 to cable segment 46 via the coupling portion 48.

[0087] For each cable segment 46, the same implementation scheme of System 2 can be provided, as it has been previously combined with Figures 1 to 4 As explained above. Therefore, for each cable segment 46, reference is made in a similar manner to the preceding description, preferred features, effects, and advantages, as explained in the context of system 2 having cable segments 4. Therefore, similar repetitions are omitted.

[0088] Each cable segment 46 is equipped with a first sensor 6, which is preferably connected to the processor unit 8 via a corresponding signal line 58. Furthermore, each first sensor 6 is equipped with a first set of curves, which is stored in the data memory 10. The system 2 thus has multiple first sensors 6 and multiple first set of curves 14. Referring to the above description, the processor unit 8 is configured to determine a first sensor distance E from the actual partial discharge 22 for each first sensor 6.

[0089] For example, if a partial discharge 22 occurs in one cable segment 46 of the cable segment, this causes a pulse 20 that propagates across all cable segments 46 due to the coupling points 48 between the cable segments 46. This could theoretically result in a first discharge signal being detected by a first sensor 6 of each cable segment 46, the first discharge signal being caused by the same partial discharge 22, however, this partial discharge only occurs in one cable segment of the cable segment 46. Therefore, the processor unit 8 is configured to determine the cable segment 46 with the actual partial discharge 22 as the identified cable segment 54 based on a first sensor distance E. In other words, the processor unit 8 can first determine the respective discharge curve and the resulting first sensor distance E based on the first discharge signal. Therefore, the corresponding first sensor distance E can be determined for each cable segment 46. Based on these multiple first sensor distances E, the processor unit 8 can then determine the cable segment 54 of the cable segment 46 as the identified cable segment 54 where the partial discharge 22 actually occurred. The first sensor distance E assigned to the cable segment 46 thus also forms an actual first sensor distance E, which can be represented by the output signal U. The output signal U can additionally indicate the identified cable segment 46. Therefore, it is preferably specified that the signal interface 12 is implemented to provide the output signal U, which indicates the identified cable segment 54 and represents the first sensor distance E between the first sensor 6 of the identified cable segment 54 and the actual partial discharge 22.

[0090] In addition, from Figure 1 , 3 Transmission system 56 can be seen in figures 4 and 5. Transmission system 56 has system 2. This is shown in different embodiments in the above figures. Transmission system 56 also has such cable segment 4. Therefore, for transmission system 56, refer in a similar manner to the previous description, preferred features, effects, and advantages.

[0091] exist Figure 6 A flowchart illustrating an advantageous embodiment of a method for operating system 2 is shown. Here, the method comprises the following steps:

[0092] a) Electrical energy is transmitted via cable segment 4;

[0093] b) An electrical signal, referred to as the first discharge signal 24, is detected by means of the first sensor 6 and is caused by the actual partial discharge 22 on the cable segment 4;

[0094] c) The first measurement signal M, representing the first discharge signal 24, is transmitted directly or indirectly from the first sensor 6 to the processor unit 8;

[0095] d) Based on the first measurement signal M and with the aid of the processor unit 8, a first curve 16 of the first curve set 14 is determined as the first discharge curve 26, wherein the first curve optimally matches the first discharge signal 24 among all the first curves 16 in the first curve set 14; and

[0096] e) The processor unit 8 determines the actual partial discharge 22 and the first sensor distance E of the first sensor 6 based on the distance to which the first discharge curve 26 belongs.

[0097] Regarding the method, reference is made in a similar manner to the preceding description, preferred features, effects, and / or advantages, as for system 2. Figures 1 to 5 As already explained, the corresponding repetition is omitted.

[0098] However, it should be noted that steps a) through e) can be performed in the order described.

[0099] If this method is implemented using system 2, such as in, for example, Figure 3 As shown, subsequent additional steps d.1) to d.3) can be performed between steps d) and e). Figure 7 The corresponding flowchart is illustrated below. The additional steps can be summarized as follows:

[0100] di) The electrical signal, referred to as the second discharge signal, is detected by means of the second sensor 28 and is caused by the same actual partial discharge 22 on the cable segment 4;

[0101] d.2) The second measurement signal N, representing the second discharge signal, is transmitted directly or indirectly from the second sensor 28 to the processor unit 8;

[0102] d.3) Using the processor unit 8, a second curve from the second curve set is determined as a second discharge curve based on the second measurement signal, wherein the second curve is optimally consistent with the second discharge signal among the second curves in the second curve set.

[0103] Here, it is also preferred that, in step e), the first sensor distance E is additionally determined by means of the processor unit 8 based on the distance to which the second discharge curve belongs.

[0104] exist Figure 8 The flowchart illustrates another implementation of the method. According to this implementation, in addition to combining... Figure 7 In addition to the steps described, the method also includes the following steps:

[0105] f) The processor unit 8 controls the first pulse feed unit 32, so that the electrical pulse, referred to as the first reference pulse 38, is fed into the cable segment 4 via the first pulse feed unit 32.

[0106] g) Detect a first signal, referred to as a first reference signal, by means of a first sensor 6, which is caused by a first reference pulse in a first reference pulse 38;

[0107] h) The first test signal O, representing the first reference signal in the first reference signal, is transmitted directly or indirectly from the first sensor 6 to the processor unit 8;

[0108] i) By means of the processor unit 8 and based on at least one first test signal O, the parameters of the cable model 4 are adapted such that the transmission characteristics represented by the cable model 4 correspond to the actual transmission characteristics of the cable segment 4 represented by the first reference pulse 38 and the first reference signal.

[0109] In addition, previously combined with the appendix Figures 6 to 8 Each of the methods described may have an additional step m), which is purely exemplary in Figure 8 The flowchart is shown together with the above. Then, the method preferably also includes the following steps:

[0110] m) The output signal U, representing the distance E of the first sensor, is transmitted via signal interface 12.

[0111] It should also be noted that "having" does not exclude other elements or steps, and "a" or "an" does not exclude multiple. Furthermore, it should be noted that the features described with reference to one embodiment of the above exemplary embodiments may also be used in combination with other features of the other embodiments described above. Reference numerals should not be considered limiting.

[0112] List of reference numerals

[0113] Amplitude

[0114] M First measurement signal

[0115] N Second measurement signal

[0116] 0 First test signal

[0117] P Second test signal

[0118] E First sensor distance

[0119] F Second sensor distance

[0120] S sensor distance

[0121] T partial discharge location

[0122] U output signal

[0123] L Axial direction

[0124] 2 System

[0125] 4 cable sections

[0126] 6 First Sensor

[0127] 8 processor units

[0128] 10. Data Storage

[0129] 12 Signal Interfaces

[0130] 14 First Curve Set

[0131] 16 First Curve

[0132] 20 pulses

[0133] 22 Partial Discharge

[0134] 24 First discharge signal

[0135] 26 First discharge curve

[0136] 28 Second Sensor

[0137] 32 First Pulse Feed Unit

[0138] 38 First reference pulse

[0139] 40 Second pulse feed unit

[0140] 42 First end

[0141] 44 Second end

[0142] 46 cable segments

[0143] 48. Coupling site

[0144] 54 identified cable segments

[0145] 56 Transmission System

[0146] 58 Signal Connection

[0147] 60 Signal Connection

[0148] 62 Signal Connection

[0149] 64 Signal Connections

[0150] 66 Control circuit

[0151] 68 Control circuit

Claims

1. A system (2) for a cable segment (4) used to transmit electrical energy, wherein, The system (2) has: The first sensor (6) is used to detect electrical signals in the cable segment (4). Processor unit (8) Data storage (10), and Signal interface (12). The data storage (10) stores a set (14) of first curves consisting of a plurality of first curves (16), each first curve representing a distance to a first sensor (6), wherein each first curve (16) represents a predetermined pulse response of an electrical pulse (20) via a cable model of a cable segment (4), the electrical pulse being caused by a modeled partial discharge (22) on the cable segment (4) at the distance to the first sensor (6) corresponding to the respective first curve (16). The first sensor (6) is configured to detect an electrical signal, referred to as the first discharge signal (24), which is caused by an actual partial discharge (22) on the cable segment (4), and the first sensor is configured to transmit a first measurement signal (M) representing the first discharge signal (24) directly or indirectly to the processor unit (8). The processor unit (8) is configured to determine a first discharge curve (26) from the first curves (16) of the first curve set (14) based on the first measurement signal (M), wherein the first curve is optimally correlated with the first discharge signal (24) among the first curves (16) of the first curve set (14). The processor unit (8) is configured to determine the actual partial discharge (22) and the first sensor distance (E) of the first sensor (6) based on the distance to which the first discharge curve (26) belongs, and The signal interface (12) is implemented to transmit an output signal (U) representing the distance (E) of the first sensor.

2. The system (2) according to claim 1, characterized in that, The system (2) has a second sensor (28) for detecting electrical signals of the cable segment (4). The data memory (10) stores a set of second curves consisting of multiple second curves, each carrying a distance to a second sensor (28). Each second curve represents a predetermined pulse response of an electrical pulse (20) via a cable model of a cable segment (4), the electrical pulse being caused by a modeled partial discharge (22) on the cable segment (4) at the distance to the second sensor (28) corresponding to the respective second curve. The first sensor (6) and the second sensor (28) are fastened to the cable segment (4) at a predetermined sensor distance from each other. The second sensor (28) is configured to detect an electrical signal, referred to as the second discharge signal, which is caused by the same actual partial discharge (22) on the cable segment (4), and the second sensor is configured to transmit a second measurement signal N representing the second discharge signal directly or indirectly to the processor unit (8). The processor unit (8) is configured to, based on the second measurement signal (N), determine one of the second curves in the second set of second curves as the second discharge curve, wherein the second curve is optimally correlated with the second discharge signal among the second curves, and The processor unit (8) is configured to determine the actual partial discharge (22) and the first sensor distance (E) of the first sensor (6) based on a predetermined sensor distance, the distance to which the first discharge curve (26) belongs, and the distance to which the second discharge curve belongs.

3. The system (2) according to claim 2, characterized in that, The system (2) has a first pulse feeding unit (32) for feeding at least one first electrical pulse into the cable segment (4). The processor unit (8) is configured to change the parameters of a cable model representing the transmission characteristics of an electrical pulse (20) on a cable segment (4). The processor unit (8) is configured to control the first pulse feed unit (32) so that an electrical pulse (20), referred to as the first reference pulse (38), is fed into the cable segment (4) via the first pulse feed unit (32). The first pulse feed unit (32) and the first sensor (6) are arranged separately. The first sensor (6) is configured to detect an electrical signal, referred to as a first reference signal and caused by a first reference pulse (38), and the first sensor is configured to transmit a first test signal (O) representing the first reference signal directly or indirectly to the processor unit (8). The processor unit (8) is configured to adapt the parameters of the cable model based on the first test signal (O) such that the transmission characteristics represented by the cable model correspond to the actual transmission characteristics of the cable segment (4) represented by the first reference pulse (38) and the first reference signal.

4. The system (2) according to claim 3, characterized in that, The system (2) has a second pulse feeding unit (40) for feeding at least one second electrical pulse into the cable segment (4). The processor unit (8) is configured to control the second pulse feed unit (40) so that an electrical pulse (20), referred to as the second reference pulse, is fed into the cable segment (4) via the second pulse feed unit (40). The second pulse feed unit (40) and the second sensor (28) are arranged separately. The second sensor (28) is configured to detect an electrical signal, referred to as the second reference signal and caused by a second reference pulse, and is configured to transmit a second test signal (P) representing the second reference signal directly or indirectly to the processor unit (8). The processor unit (8) is configured to adapt the parameters of the cable model based on the first test signal (O) and the second test signal (P), such that the transmission characteristics represented by the cable model correspond to the actual transmission characteristics of the cable segment (4) represented by the first reference pulse (38) and the first reference signal and / or by the second reference pulse and the second reference signal.

5. The system (2) according to claim 4, characterized in that, The first sensor (6) and the second pulse feed unit (40) are configured as a common first converter unit.

6. The system (2) according to claim 5, characterized in that, The second sensor (28) and the first pulse feed unit (32) are configured as a common second converter unit.

7. The system (2) according to any one of claims 4 to 6, characterized in that, The processor unit (8) is configured such that the first pulse feed unit (32) and / or the second pulse feed unit (40) are configured to periodically feed reference pulses and to adapt the parameters of the cable model after each reference pulse feed.

8. The system (2) according to any one of claims 2 to 6, characterized in that, The first sensor (6) is configured to periodically detect electrical signals of the cable segment (4), and the processor unit (8) is configured to determine the corresponding first discharge curve (26) in each case where the electrical signal detected by the first sensor (6) forms a first discharge signal (24), and to determine the first sensor distance (E) between the first sensor (6) and the corresponding partial discharge (22) based on the first discharge curve (26).

9. The system (2) according to claim 8, characterized in that, The second sensor (28) is configured to periodically detect electrical signals of the cable segment (4), and the processor unit (8) is configured to determine the corresponding second discharge curve in each case where the electrical signal detected by the second sensor (28) forms a second discharge signal, and to determine the corresponding partial discharge (22) and the first sensor distance (E) of the first sensor (6) based on the predetermined sensor distance, the distance to which the first discharge curve (26) belongs, and the distance to which the second discharge curve belongs.

10. The system (2) according to claim 8, characterized in that, The processor unit (8) is configured to determine the frequency of multiple actual partial discharges (22) at the same distance from the first sensor (6), and the output signal (U) also represents the frequency.

11. The system (2) according to claim 10, characterized in that, The processor unit (8) is configured to determine at least one characteristic parameter of a plurality of actual partial discharges (22) at the same distance from the first sensor (6), and the output signal (U) also represents the determined characteristic parameter.

12. The system (2) according to claim 11, characterized in that, The processor unit (8) is configured to generate an alarm signal when the frequency of a local discharge (22) is greater than a predetermined threshold frequency and / or when the obtained characteristic parameter of the local discharge (22) is greater than a predetermined threshold characteristic parameter, and the signal interface (12) is configured to transmit the alarm signal.

13. The system (2) according to claim 11, characterized in that, The processor unit (8) is configured to determine the aging state of the cable segment (4) based on the frequency of partial discharge (22) and / or the at least one characteristic parameter and / or adapted parameter of the partial discharge (22), wherein the output signal (U) also represents the aging state.

14. The system (2) according to any one of claims 1 to 6, characterized in that, The cable segment (4) has a plurality of cable segments (46) arranged sequentially along the cable segment (4), wherein the ends of the cable segments (46) facing each other at their ends are connected to each other to form a coupling portion (48). Each cable segment (46) is equipped with a first sensor (6) and a first curve set (14) for the corresponding first sensor (6), such that the system (2) has multiple first sensors (6) and multiple first curve sets (14) are stored by a data memory (10). The processor unit (8) is configured to determine the actual partial discharge (22) and the first sensor distance (E) of the corresponding first sensor (6) for each first sensor (6). The processor unit (8) is configured to determine, based on a first sensor distance (E), the cable segment (46) with partial discharge (22) as the identified cable segment (46), and The signal interface (12) is configured to provide an output signal (U) indicating the identified cable segment (46) and the distance (E) between the first sensor (6) of the identified cable segment (46) and the first sensor of the partial discharge (22).

15. A transmission system (56) for transmitting electrical energy, said transmission system having: Cable segment (4), and The system (2) according to any one of claims 1 to 14.

16. A method for operating a system (2), said system for a cable segment (4) used to transmit electrical energy, wherein, The system (2) has a first sensor (6) for detecting electrical signals of a cable segment (4), a processor unit (8), a data memory (10), and a signal interface (12), wherein the data memory (10) stores a first curve set (14) consisting of a plurality of first curves (16), each of the plurality of first curves having a corresponding distance to the first sensor (6), wherein each first curve (16) represents a predetermined pulse response of an electrical pulse (20) by means of a cable model of the cable segment (4), the electrical pulse being caused by a modeled partial discharge (22) on the cable segment (4) at the distance to the first sensor (6) corresponding to the corresponding first curve (16), and the method has the following steps: a) Power is transmitted via cable segment (4). b) An electrical signal, referred to as the first discharge signal (24) and caused by an actual partial discharge (22) on the cable segment (4), is detected by means of a first sensor (6). c) The first measurement signal (M) representing the first discharge signal (24) is transmitted directly or indirectly from the first sensor (6) to the processor unit (8). d) Based on the first measurement signal (M) and with the aid of the processor unit (8), a first curve (16) of the first curve set (14) is determined as the first discharge curve (26), wherein the first curve is optimally correlated with the first discharge signal (24) among the first curves (16) of the first curve set (14), and e) The processor unit (8) determines the actual partial discharge (22) and the first sensor distance E of the first sensor (6) based on the distance to which the first discharge curve (26) belongs.

17. The method according to claim 16, characterized in that, The system (2) has a second sensor (28) for detecting electrical signals of the cable segment (4), wherein the data memory (10) stores a set of second curves consisting of a plurality of second curves, each second curve having a corresponding distance to the second sensor (28), wherein each second curve represents a predetermined pulse response of an electrical pulse (20) by means of a cable model of the cable segment (4), the electrical pulse being caused by a modeled partial discharge (22) on the cable segment (4) at a distance to the second sensor (28) corresponding to the corresponding second curve, wherein the first sensor (6) and the second sensor (28) can be arranged on the cable segment (4) at a predetermined sensor distance between each other, and the method has the following further steps: d.1) An electrical signal, referred to as the second discharge signal, is detected by means of a second sensor and is caused by the same actual partial discharge (22) on the cable segment (4). d.2) The second measurement signal (N), representing the second discharge signal, is transmitted directly or indirectly from the second sensor (28) to the processor unit (8), and d.3) Based on the second measurement signal (N) and with the aid of the processor unit (8), a second curve from the second curve set is determined as the second discharge curve, wherein the second curve is optimally correlated with the second discharge signal among the second curves in the second curve set. In step e), the first sensor distance (E) is additionally determined by the processor unit (8) based on the distance to which the second discharge curve belongs.

18. The method according to claim 17, characterized in that, The system (2) has a first pulse feeding unit (32) for feeding at least one first electrical pulse into a cable segment (4), wherein a processor unit (8) is configured to change parameters of a cable model representing the transmission characteristics of the electrical pulse (20) on the cable segment (4), wherein the first pulse feeding unit (32) is arranged spaced apart from a first sensor (6), and the method has the following further steps: f) The processor unit (8) controls the first pulse feeding unit (32) so that an electrical pulse (20), referred to as the first reference pulse (38), is fed into the cable segment (4) via the first pulse feeding unit (32). g) An electrical signal, referred to as a first reference signal, is detected by means of a first sensor (6), each of which is caused by a first reference pulse (38). h) The first test signal (O), representing one of the first reference signals, is transmitted directly or indirectly from the first sensor (6) to the processor unit (8), and i) By means of the processor unit (8) and based on the first test signal (O), the parameters of the cable model are adapted such that the transmission characteristics represented by the cable model correspond to the actual transmission characteristics of the cable segment (4) represented by the first reference pulse (38) and the first reference signal.

19. The method according to claim 18, characterized in that, The system (2) has a second pulse feeding unit (40) for feeding at least one second electrical pulse into a cable segment (4), wherein the second pulse feeding unit (40) is arranged spaced apart from the second sensor (28), and the method has the following further steps: j) The processor unit (8) controls the second pulse feeding unit (40) so that the electrical pulse (20), called the second reference pulse, is fed into the cable segment (4) through the second pulse feeding unit (40). k) Detect the electrical signal, referred to as the second reference signal and caused by the second reference pulse, using a second sensor (28), and l) The second test signal (P), representing the second reference signal, is transmitted directly or indirectly from the second sensor (28) to the processor unit (8). In step i), the parameters of the cable model are adapted by the processor unit (8) based on the first test signal (O) and the second test signal (P) so that the transmission characteristics represented by the cable model correspond to the actual transmission characteristics of the cable segment (4) represented by the first reference pulse (38) and the second reference signal and / or by the second reference pulse and the second reference signal.

20. The method according to claim 16 or 17, characterized in that, The method has the following further steps: m) transmits an output signal (U) representing the distance (E) of the first sensor via the signal interface (12).

21. The method according to claim 16 or 17, characterized in that, The method steps a) through e) are performed once or repeatedly.

22. The method according to claim 20, characterized in that, Steps g) to j) or steps g) to m) are performed once, periodically, or before each set of steps a) to e) of the method.

23. The method according to claim 19, characterized in that, The processor unit (8) uses the cable model updated with the adapted parameters to calculate the first curve set (14) and / or the second curve set, and stores the first curve set and / or the second curve set in the data memory (10).

24. The method according to claim 23, characterized in that, After each adaptation of the cable model parameters, the processor unit (8) uses the cable model updated by the adapted parameters to calculate the first curve set (14) and / or the second curve set, and stores the first curve set and / or the second curve set in the data memory (10).

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