System and method for detecting electrical short circuits

Abstract

To provide methods and systems of detecting short circuits in an electrical system, such as a dynamic braking grid of a vehicle.SOLUTION: The methods and systems measure a characteristic of an electrical current that is conducted through one or more resistive elements of an electrical system 104. The electrical current is supplied to the electrical system from a power source 102 as an applied voltage. A resistance change signal representative of a change in one or more electrical resistances of the one or more resistive elements is determined. The resistance change signal is based at least in part on a difference between the characteristic of the electrical current that is measured and a low pass filtered value of one or more of the characteristic of the electrical current that is measured or the applied voltage supplied by the power source. A short circuit event is identified based at least in part on the resistance change signal.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments of the inventive subject matter described herein relate to the detection of electrical short circuits in an electronic system, such as a power resistor.

Background Art

[0002] Known electronic systems include those that conduct current to a resistor to dissipate the current. For example, some vehicles include a grid having a conductive ribbon that receives power generated by a motor during regenerative braking or during dynamic braking. This power is generated by the motor and acts to slow or stop the movement of the vehicle. The power is conducted to the grid to be dissipated as heat from the vehicle's regenerative braking system.

[0003] The grid can be formed from one or more series of resistors. These resistors can be implemented in conductive plates that are positioned relatively close to each other. Over time, due to damage to the grid, standard wear, or other reasons, the relative positions of the resistors can begin to change. If the resistors contact each other (e.g., due to vibration or other movement), an internal electrical short circuit between the resistors can occur. This short circuit can damage the grid, damage the regenerative braking system, and otherwise have an adverse effect on the operation of the vehicle.

Summary of the Invention

[0004] In one embodiment, a method (for example, for detecting a short circuit in an electrical system) includes the step of measuring the characteristics of a current conducted through one or more resistive elements in the electrical system. The current is supplied to the electrical system from a power source as an applied voltage. The method also includes the step of determining a resistance change signal representing a change in one or more electrical resistances of one or more resistive elements. The resistance change signal may be at least partially based on the difference between the characteristics of the current being measured and one or more low-pass filtered values ​​of the characteristics of the current being measured or the applied voltage supplied by the power source. The method may also include the step of identifying a short-circuit event at least partially based on the resistance change signal.

[0005] In another embodiment, the system (e.g., a detection system) includes a sensing device and a processing assembly. The sensing device is configured to measure the characteristics of a current conducted through one or more resistive elements in an electrical system. The current may be supplied to the electrical system from a power source as an applied voltage. The processing assembly may be configured to determine a resistance change signal representing a change in one or more electrical resistances of one or more resistive elements. The resistance change signal may be at least partially based on the difference between the characteristics of the current being measured and one or more low-pass filtered values ​​of the characteristics of the current being measured or the applied voltage supplied by the power source. The processing assembly may be configured to identify a short-circuit event at least partially based on the resistance change signal. [Brief explanation of the drawing]

[0006] Here, let's briefly refer to the attached diagram. [Figure 1] A power system in one embodiment is illustrated. [Figure 2] Figure 1 illustrates the electrical system of the power system shown, and a schematic diagram of an electrical short-circuit detection system in one embodiment. [Figure 3] Figure 1 shows a circuit diagram of one embodiment of the electrical system and Figure 2 shows a detection system. [Figure 4]This is a flowchart of one embodiment of a method for detecting short-circuit events. [Modes for carrying out the invention]

[0007] One or more embodiments of the subject matter of the invention described herein detect electrical short circuits in electronic systems. In one embodiment, the systems and methods described herein may be used to detect electrical short circuits in regenerative braking grids (DBGs) of vehicles such as railway vehicles and other off-highway vehicles (OHVs). However, not all embodiments are limited to DBGs or railway vehicles. One or more embodiments may be used to detect short circuits in non-vehicle systems and other systems, including vehicle systems other than railway vehicles or OHVs.

[0008] During DBG operation, the conduction plates of the DBG may experience an electrical short circuit, allowing the DBG current to bypass at least some of the electrical resistance formed by the plates. The plates can also experience a short circuit if they are subjected to airflow, for example, from a blower (e.g., a fan) that dissipates heat generated by the current into the air around the plates. However, the plates can also experience a short circuit due to the thermal cycling of the DBG, which can cause distortion and / or transitions of the metallic elements. These short circuits can form localized hot spots between two or more plates, which can ultimately lead to sparks, melting, arcing, and DBG failure.

[0009] To prevent DBG failures, the systems and methods described herein may provide early detection of electrical short circuits. Early detection of short circuits allows for preventative inspection and maintenance, thereby avoiding more serious damage and / or downtime to the DBG or other electrical systems.

[0010] Figure 1 illustrates a power system (100) in one embodiment. The power system (100) is shown as a locomotive, but it may alternatively be a different type of system or a different type of vehicle that is not a vehicle. The system (100) includes a power source (102), such as a traction motor that generates power during regenerative braking. Alternatively, the power source (102) may represent an alternator, generator, battery or other power source. The power source (102) generates an electric current, which is conducted to an electrical system (104). The electrical system (104) includes one or more resistive elements, such as power resistors. These resistive elements convert the current from the power source (102) into heat. The heat can be dissipated from the power system (100) by, for example, a blower (e.g., a fan). In the illustrated embodiment, the power source (102) may include a traction motor that generates an electric current during regenerative braking of the electric system (100). The electrical system (104) may include a DBG that converts electrical energy into heat for dissipation.

[0011] Figure 2 illustrates a schematic diagram of an electrical system (104) and an electrical short-circuit detection system (200) (referred to as the "detection system" in Figure 2) in one embodiment. The system (104) includes several electrical resistive elements (202) connected in series with each other in a conductive state. In the illustrated embodiment, the resistive elements (202) are conductive plates, such as conductive two-dimensional bodies, with an outer shape in which two orthogonal directions are longer than a third orthogonal direction. Alternatively, the resistive elements (202) may be other types of resistors. During the operation of the system (104), power from the power source (102) is conducted through the resistive elements (202). The resistive elements (202) reduce the flow of current through the electrical system (104) and convert the power into heat. As one example, during regenerative braking of a vehicle, power generated by the vehicle's traction motor can be conducted to the resistive elements (202) (e.g., DBG) and dissipated as heat.

[0012] The resistive elements (202) may be arranged at relatively close intervals. During operation, the relative positions of the resistive elements (202) may change due to the airflow generated by the blower, and / or they may bend or deform due to the heat generated by the power conducted to the resistive elements (202). This change in position and / or deformation may cause the resistive elements (202) to come into contact with each other and cause an electrical short circuit. The short circuit may damage the power system (100) and / or limit the operation of the power system (100).

[0013] The detection system (200) is electrically connected to the electrical system (104) at one or more points and monitors the electrical characteristics of the current conducted through the electrical system (104). The detection system (200) monitors changes in the electrical resistance of the electrical system (104) over time and detects electrical short circuits based on these changes. For example, while the resistive elements (202) are not in contact with each other, the voltage and / or current conducted through the resistive elements (202) may be proportional to the voltage generated by the power supply (102). The voltage and / or current generated by the power supply (102) and conducted through the electrical system (104) is the voltage or current applied to the resistive elements (202), so the applied voltage (V dc The voltage and / or current (referred to herein as conduction voltage or conduction current) conducted through the resistive element (202) may be proportional to the applied voltage and / or applied current by one or more proportionality constants. For example, the product of the conduction voltage and the proportionality constant is equal to the input voltage, and / or the product of the conduction current and the same or another proportionality constant is equal to the input voltage. The proportionality constants are the same or substantially the same over time.

[0014] However, if two or more resistive elements (202) come into contact with each other, at least momentarily, causing an electrical short circuit, the proportionality constant may change abruptly. Therefore, abrupt changes in the ratio of conduction voltage and / or conduction current may indicate an electrical short circuit. The detection system (200) monitors changes in conduction voltage and conduction current, and / or changes in the ratio of these voltages and / or currents, to quickly identify the short circuit before it damages the operation of the electrical system (104) and / or the power system (100).

[0015] Figure 3 is a circuit diagram of one embodiment of an electrical system (104) and a detection system (200). Various groups of resistors (202) are connected in parallel with each other, and within these groups of resistors (202) are connected in series with each other. For example, resistors (202) labeled "1", "2", and "3" are connected in series with each other in the first group, resistors (202) labeled "4", "5", and "6" are connected in series with each other in the second group, resistors (202) labeled "7", "8", and "9" are connected in series with each other in the third group, and resistors (202) labeled "10", "11", and "12" are connected in series with each other in the fourth group, and the first, second, third, and fourth groups may be connected in parallel with each other. By placing a switch (304) on the opposite side of each group of resistors (202), it is possible to control which resistor (202) receives the applied current from the power supply (102).

[0016] The detection system (200) includes a sensing device (300) which is conductedly connected to a resistive element (202). The sensing device (300) represents one or more device parts that measure the characteristics of the current supplied to the electrical system (104) by a power supply (102). For example, the sensing device (300) can measure conducted voltage and / or conducted current. For example, the sensing device (300) may include one or more voltmeters and / or ammeters (302) ("VAM" in Figure 3), a high-voltage filter (306) ("High V" in Figure 3), and / or a low-voltage filter (308) ("Low V" in Figure 3). The voltmeters and ammeters (302) and / or filters (306, 308) can measure the voltage between resistive elements (202) at the locations shown in Figure 3 and / or other locations, and / or the voltage drop between two or more resistive elements (202). Alternatively, the sensing device (300) may include another type of sensor that measures voltage and / or current conducted between and / or through the resistive elements (202).

[0017] The detection system (200) may also include a processing assembly (310) operably connected to a sensing device (300). For example, the processing assembly (310) and the sensing device (300) may be connected by one or more wired and / or wireless connections. The processing assembly (310) includes one or more processors (312) ("Processing" in Figure 3, e.g., microprocessors, controllers, or other electrical logic-based devices) and / or hardware and / or electrical circuits connected thereto. This circuit may include an input / output module (314) ("I / O" in Figure 3) and an input / output board (316) ("CIO" in Figure 3). The input / output module (314) may represent hardware and / or electrical circuits connected thereto, including one or more processors that generate output signals for presentation to an operator (e.g., signals transmitted to a display device to warn the operator of a detected short circuit). The input / output board (316) may represent hardware and / or electrical circuits, including one or more processors, and / or connected to them, for transmitting signals to a display device or other output device. Optionally, the input / output board (316) may receive signal inputs from one or more other devices, such as signals representing applied voltages generated by a power supply (102) and conducted to an electrical system (104).

[0018] Figure 4 is a flowchart relating to one embodiment of a method (400) for detecting a short-circuit event. In one embodiment, the method (400) may be carried out by a detection system (300). In (402), the conducted voltage and conducted current are measured by the sensing device (300). In (404), the applied voltage and / or applied current supplied to the electrical system (104) by the power supply (102) is determined. For example, the sensing device (300) is connected to the electrical system (104) at one or more points and measures the applied voltage from the power supply (102).

[0019] (406) calculates the difference between the measured voltage and / or measured current (e.g., conduction voltage and / or conduction current) and the ratio after filtering between the measured voltage and / or measured current and the applied voltage and / or applied current. These differences can be referred to as resistance change signals.

[0020] The processing assembly (310) can calculate the ratio of the conduction voltage and / or conduction current and determine the proportionality constant of the electrical system (104). For example, the processing assembly (310) divides the conduction voltage measured between the second and third resistance elements (202) (elements "2" and "3" in FIG. 3) by the conduction voltage measured between the fifth and sixth resistance elements (202) (elements "5" and "6" in FIG. 3), between the eighth and ninth resistance elements (202) (elements "8" and "9" in FIG. 3), between the tenth and eleventh resistance elements (202) (elements "10" and "11" in FIG. 3), or between another pair of resistance elements (202). Further ratios can be measured to calculate additional proportionality constants for the electrical system (104).

[0021] During normal operation (e.g., when there is no short circuit), the proportionality constant is the same or substantially the same (varying within a specified threshold, e.g., 1%, 3%, 5% or another value). However, over time, the resistance provided by the resistance element (202) can change slowly with respect to time. As a result, the proportionality constant can change slowly with respect to time. The proportionality constant can be referred to as a resistance change signal. In a normal state (e.g., when there is no short circuit), the change in the proportionality constant may simply contain noise and is not an actual change in the proportionality constant. A short circuit can occur during a contact event between two or more resistance elements (202). In such a contact event, the resistance change signal rises above the noise and can indicate a short circuit.

[0022] In one embodiment, the processing assembly (310) can calculate a resistance change signal from an applied voltage and a conduction voltage. Alternatively, the resistance change signal can be calculated from an applied current and a conduction current. Although the description herein focuses on calculating a resistance change signal from a voltage, not all embodiments are limited to the use of voltage.

[0023] One example of a resistance change signal that can be calculated by the processing assembly (310) is a ratio deviation signal. In one embodiment, the processing assembly (310) calculates the ratio deviation signal as follows: <​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​For example, start and end within 100 milliseconds, 50 milliseconds, 0.1 seconds, or other time intervals. TIFF0007904946000006.tif14170 An increase or decrease can be ignored, while an increase or decrease that lasts longer than the specified time can be ignored. TIFF0007904946000007.tif14170 An increase or decrease is TIFF0007904946000008.tif14170 It is used as the value.

[0024] TIFF0007904946000009.tif14170 The value of can be used as a baseline or expected value for the ratio deviation signal. Within a time frame in which the proportionality constant does not change significantly, TIFF0007904946000010.tif14170 The value and TIFF0007904946000011.tif14170 The value is close to a certain number, and as a result, the ratio deviation signal is small or zero. However, within a time period in which the proportionality constant changes significantly, TIFF0007904946000012.tif14170 The value and TIFF0007904946000013.tif14170 The values ​​are far apart, and as a result, the relative deviation signal becomes larger.

[0025] Another example of a resistance change signal that can be calculated by the processing assembly (310) is a voltage deviation signal. In one embodiment, the processing assembly (310) calculates the voltage deviation signal as follows: TIFF0007904946000014.tif22170(Equation 2) In this case, VoltageDeviation(t) represents the voltage deviation signal.

[0026] Another example of a resistance change signal that can be calculated by the processing assembly (310) is a squared deviation signal, as follows: TIFF0007904946000015.tif7170 TIFF0007904946000016.tif7170 (Equation 3) At this time, TIFF0007904946000017.tif7170 This represents the squared deviation signal, TIFF0007904946000018.tif7170 teeth TIFF0007904946000019.tif7170 This represents the low-pass filter processing, and TIFF0007904946000020.tif7170 is TIFF0007904946000021.tif7170 This represents the low-pass filter processing.

[0027] In (408), a determination is made as to whether the difference between the measured voltage and / or measured current (e.g., conducted voltage and / or conducted current) and the filtered ratio of the measured voltage and / or measured current to the applied voltage and / or applied current indicates a short-circuit event. For example, the processing assembly (310) may examine the resistance change signal to identify a short-circuit event.

[0028] With respect to the ratio deviation signal (RatioDeviation(t)) described above, a short-circuit event can be identified by the absolute value of the ratio deviation signal that exceeds the threshold (K). The threshold is selectable, which changes the sensitivity of the detection system (200). For example, if the threshold (K) is small, the detection system (200) will be more sensitive to short circuits but also more likely to falsely identify short-circuit events, while if the threshold (K) is large, the sensitivity to short circuits will be smaller but the likelihood of falsely identifying short-circuit events will be lower.

[0029] With respect to the Voltage Deviation(t) described above, short-circuit events can be identified by a processing assembly (312) that monitors the value of the Voltage Deviation(t). For example, a short-circuit event can be identified by a threshold(K) and V base It can be identified by the absolute value of the voltage deviation signal that exceeds the product of (t).

[0030] With respect to the VoltageSquaredDeviation(t) described above, short-circuit events can be identified by a processing assembly (312) that monitors the value of the VoltageSquaredDeviation(t). For example, a short-circuit event can be identified by a threshold (K), V base (t) and <V base It can be identified by corresponding to the absolute value of the squared deviation signal that exceeds the product of (t).

[0031] If a short-circuit event is detected, the flow of method (400) can proceed to (410). Otherwise, the flow of method (400) can return to (402) to further monitor the electrical system (104). In (410), the cumulative value of the short-circuit events is changed. In contrast to determining that a short-circuit event has occurred each time a resistance change signal indicates a short circuit, for example, the processing assembly (310) can track a cumulative value whose value changes based on the number, duration, and / or energy of the short-circuit events.

[0032] As an example, the processing assembly (310) can calculate a cumulative value of short-circuit events as the total number of short-circuit events. An increase in such a cumulative value may indicate an increase in the severity of the short-circuit events.

[0033] As another example, the processing assembly (310) can calculate a cumulative value as the total duration of short-circuit events. For example, the total duration during which the resistance change signal exceeds one or more thresholds described above can be calculated as a cumulative value. If a short-circuit event lasts for 1 second, followed by a 0.5-second short-circuit event and another 2-second short-circuit event, the total duration of the short-circuit events could be 3,5. An increase in total duration may mean increased damage to the resistive element (202) compared to a shorter total duration. The total duration can be reset to 0, for example, after the power system (100) has moved from the starting position to the target position.

[0034] As another example, the processing assembly (310) can calculate the cumulative value as energy of a short-circuit event. For example, the processing assembly (310) can calculate the cumulative value as the time integral of the squared deviation signal during short-circuit event detection. This cumulative value may represent, and / or be proportional to, the thermal energy or heat quantity directed toward the contact point between the resistive elements (202) where the short-circuit event is occurring.

[0035] In (412), a determination is made as to whether the cumulative values ​​indicate that the electrical system (104) is damaged (and therefore has caused a short circuit event). In one embodiment, the processing assembly (310) can compare one or more cumulative values ​​with a specified threshold value. If the cumulative values ​​exceed the threshold value, the processing assembly (310) can determine that the electrical system (104) is likely damaged. As a result, the flow may proceed to (414). Otherwise, the flow of method (400) may return to (402).

[0036] A warning signal is generated in (414). This warning signal is generated by the processing assembly (310) and may be presented to the operator of the power system (100). The warning signal may indicate to the operator that the electrical system (104) is in the initial stages of damage, such as delamination. In one embodiment, the cumulative value may be compared to several different thresholds (e.g., various delamination stages) representing different levels of damage. The thresholds may be determined by testing the electrical system (104) to a failure state while measuring the above quantities, during which the thresholds are set based on engineering judgment. The warning signal may be used to control the operation of the power system (100). For example, the warning signal may be used to disable the power system (100) to reduce power output, or otherwise reduce the operation of the power system (100) to prevent further damage to the electrical system (104).

[0037] Method (400) may be repeated one or more times during the operation of the power system (100). For example, the flow of method (400) may return to (402) for additional monitoring of the electrical system (104).

[0038] In one embodiment, a method (for example, for short-circuit detection in an electrical system) includes the step of measuring the characteristics of a current conducted through one or more resistive elements in an electrical system. The current is supplied to the electrical system from a power source as an applied voltage. The method further includes the step of determining a resistance change signal representing a change in one or more electrical resistances of one or more resistive elements. The resistance change signal may be at least partially based on the difference between the characteristics of the current being measured and one or more low-pass filtered values ​​of the characteristics of the current being measured or the applied voltage supplied by the power source. The method may further include the step of identifying a short-circuit event at least partially based on the resistance change signal.

[0039] In one embodiment, the applied voltage can be generated by the vehicle's traction motor during regenerative braking of the vehicle, one or more resistive elements can include one or more resistors of the regenerative braking grid, and / or the conducted voltage can include a voltage drop across one or more resistors.

[0040] In one embodiment, the resistance change signal may represent one or more changes in electrical resistance caused by an increase in heat within one or more resistive elements due to a short-circuit event.

[0041] In one embodiment, the characteristics of the measured current may include a voltage drop across at least one of the resistive elements.

[0042] In one embodiment, the resistance change signal may represent the difference between the ratio of the voltage drop across at least one of the resistive elements to the applied voltage and the value of the ratio of the voltage drop across at least one of the resistive elements to the applied voltage after low-pass filtering.

[0043] In one embodiment, a short-circuit event may be identified in correspondence with the absolute value of a resistance change signal that exceeds a specified non-zero threshold.

[0044] In one embodiment, the resistance change signal may represent the difference between the voltage drop across at least one of the resistive elements and the product of the applied voltage and the low-pass filtered value of the ratio of the voltage drop across at least one of the resistive elements to the applied voltage.

[0045] In one embodiment, a short-circuit event may be identified in relation to the absolute value of a resistance change signal that exceeds the product of the applied voltage and a specified non-zero threshold.

[0046] In one embodiment, the resistance change signal may represent the difference between a first product of the voltage drop across at least one of the resistive elements and the low-pass filtered value of the applied voltage, and a second product of the applied voltage and the low-pass filtered value of the voltage drop across at least one of the resistive elements.

[0047] In one embodiment, a short-circuit event may be identified in relation to the absolute value of a resistance change signal that exceeds the product of the applied voltage, the voltage drop across at least one resistive element, and a specified non-zero threshold.

[0048] In one embodiment, the method may further include the steps of monitoring the number of times a short-circuit event is identified, and generating a warning signal indicating damage to the electrical system, corresponding to the number of times a short-circuit event is identified that exceeds a specified non-zero threshold.

[0049] In one embodiment, the method may further include the steps of monitoring the total duration of short-circuit events and generating a warning signal indicating damage to the electrical system, corresponding to a total duration exceeding a specified non-zero threshold.

[0050] In one embodiment, the method may further include the steps of monitoring the time integral of a resistance change signal and generating a representative warning signal indicating damage to an electrical system, corresponding to a time integral exceeding a specified non-zero threshold.

[0051] In one embodiment, the method may further include a step of generating a warning signal, at least in part, based on the identification of a short-circuit event. The warning signal can indicate damage to the electrical system to the operator of a power system, including an electrical system.

[0052] In another embodiment, the system (e.g., a detection system) includes a sensing device and a processing assembly. The sensing device is configured to measure the characteristics of a current conducted through one or more resistive elements of an electrical system. The current may be supplied to the electrical system from a power source as an applied voltage. The processing assembly may be configured to determine a resistance change signal representing a change in one or more electrical resistances of one or more resistive elements. The resistance change signal may be at least partially based on the difference between the characteristics of the current being measured and one or more low-pass filtered values ​​of the characteristics of the current being measured or the applied voltage supplied by the power source. The processing assembly may further be configured to identify a short-circuit event at least partially based on the resistance change signal.

[0053] In one embodiment, the applied voltage can be generated by the vehicle's traction motor during regenerative braking of the vehicle, one or more resistive elements can include one or more resistors of the regenerative braking grid, and the conducted voltage can include a voltage drop across one or more resistors.

[0054] In one embodiment, the resistance change signal may represent one or more changes in electrical resistance caused by an increase in heat in one or more resistive elements due to a short-circuit event.

[0055] In one embodiment, the characteristics of the measured current may include a voltage drop across at least one of the resistive elements.

[0056] In one embodiment, the resistance change signal can represent the difference between the ratio of the voltage drop across at least one of the resistive elements to the applied voltage and the value of the ratio of the voltage drop across at least one of the resistive elements to the applied voltage after low-pass filtering.

[0057] In one embodiment, the processing assembly may be configured to identify a short-circuit event in response to the absolute value of a resistance change signal that exceeds a specified non-zero threshold.

[0058] In one embodiment, the resistance change signal can represent the difference between the voltage drop across at least one of the resistive elements and the product of the applied voltage and the low-pass filtered value of the ratio of the voltage drop across at least one of the resistive elements to the applied voltage.

[0059] In one embodiment, the processing assembly may be configured to identify a short-circuit event corresponding to the absolute value of a resistance change signal that exceeds the product of the applied voltage and a specified non-zero threshold.

[0060] In one embodiment, the resistance change signal can represent the difference between a first product of the low-pass filtered values ​​of at least one resistive element and the applied voltage, and a second product of the low-pass filtered values ​​of the applied voltage and the voltage drop across at least one resistive element.

[0061] In one embodiment, the processing assembly may be configured to identify a short-circuit event in response to the absolute value of a resistance change signal that exceeds the product of an applied voltage, a voltage drop across at least one resistive element, and a specified non-zero threshold.

[0062] In one embodiment, the processing assembly may be configured to monitor the number of times a short-circuit event is identified and to generate an alarm signal indicating damage to the electrical system, corresponding to the number of times a short-circuit event is identified that exceeds a specified non-zero threshold.

[0063] In one embodiment, the processing assembly may be configured to monitor the total duration of short-circuit events and generate a warning signal indicating damage to the electrical system, corresponding to a total duration that exceeds a specified non-zero threshold.

[0064] In one embodiment, the processing assembly may be configured to monitor the time integral of a resistance change signal and generate a warning signal indicating damage to the electrical system, corresponding to a time integral that exceeds a specified non-zero threshold.

[0065] In one embodiment, the processing assembly may be configured to generate a warning signal, at least in part, based on the identification of a short-circuit event. The warning signal can indicate damage to the electrical system to the operator of a power system, including an electrical system.

[0066] It should be understood that the above description is intended to be descriptive and not restrictive. For example, the embodiments (and / or aspects thereof) described above may be used in combination with each other. In addition, many modifications can be made to the teachings of the subject matter of the invention to adopt specific situations or materials without departing from the scope of the invention. The dimensions and types of materials described herein are intended to define parameters of the subject matter of the invention, but they are not restrictive and are typical embodiments. Many other embodiments will be apparent to those skilled in the art upon reviewing the above description. Accordingly, the scope of the subject matter of the invention should be determined by referring to the appended claims, along with the full range of equivalents enjoyed by the claims. In the appended claims, the terms “including” and “in which” are used as plain English synonyms for “comprising” and “wherein,” respectively. Furthermore, in the following claims, terms such as “first,” “second,” and “third” are used merely as labels and are not intended to impose numerical requirements on their subjects. Moreover, the following limitations on the claims are not written in the form of “means plus function,” and such limitation of claims is not intended to be interpreted under 35 U.S. SC § 112(f) unless it explicitly uses the phrase “means for” followed by a description of function and is followed by further structure.

[0067] This written description discloses several embodiments of the subject matter of the present invention using examples, and enables a person skilled in the art to practice embodiments of the subject matter, including the creation and use of any device or system, and the implementation of the methods included. The patentable scope of the subject matter of the present invention is defined by the claims and may include other examples conceivable by a person skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the written language of the claims, or if they include equivalences of structural elements that do not substantially differ from the written language of the claims.

[0068] The foregoing description relating to specific embodiments of the subject matter of the present invention will be better understood when read in conjunction with the accompanying drawings. To the extent that the drawings show schematic diagrams of functional blocks of various embodiments, functional blocks do not necessarily indicate separations between hardware circuits. Therefore, for example, one or more functional blocks (e.g., processors or memory) can be implemented on a single piece of hardware (e.g., a general-purpose message processor, microcontroller, random access memory, hard disk, etc.). Similarly, programs can be standalone programs, incorporated as subroutines in an operating system, or functions of an installed software package. Various embodiments are not limited to the arrangements and means shown in the drawings.

[0069] Where used herein, elements or processes listed in the singular and preceded by the words "a" or "an" should be understood not to exclude multiple such elements or processes unless expressly stated otherwise. Furthermore, references to "one embodiment" in the subject matter of the invention are not intended to be construed as excluding the existence of additional embodiments containing similarly listed features. Moreover, unless expressly stated otherwise, embodiments "comprising," "including," or "having" one or more elements having a particular characteristic may include additional elements that do not possess that characteristic.

Claims

1. (1) A step of measuring the characteristics of a current conducted through one or more resistive elements of an electrical system, which is generated when a voltage is supplied to the electrical system mounted on the vehicle from a power source mounted on the vehicle, and which has an outer shape in which a first direction and a second direction orthogonal to them are longer than a third direction orthogonal to them. (2) A processing assembly including at least one processor, connected to the sensing device by wired or wireless connection, performs the steps of determining resistance change signals of the one or more resistive elements based on filtering using the characteristics of the current measured in step (1), (3) A step in which the processing assembly identifies a short-circuit event based on the resistance change signal determined in step (2), wherein the short-circuit event is identified when the resistance change signal exceeds a selected threshold among a first threshold for a certain sensitivity and a second threshold for a sensitivity greater than the first threshold and less than the certain sensitivity, (4) The process assembly monitors the total number of identified short-circuit events, the total duration of the short-circuit events which is reset to zero after the vehicle moves from the starting position to the target position, and the cumulative value of the thermal energy of the short-circuit events. (5) The process assembly generates a warning signal indicating damage to the electrical system in response to one or more of the following: the total number of identified short-circuit events exceeds a first designated non-zero threshold; the total duration exceeds a second designated non-zero threshold; and the cumulative value of the thermal energy exceeds a third designated non-zero threshold, to be presented to the operator of the vehicle and to reduce the operation of the vehicle in order to prevent damage to the electrical system; A method including, The characteristics of the current to be measured are determined by the voltage drop across the one or more resistive elements caused by the current flowing through them. Furthermore, the filtering process is a process that removes the characteristics and / or applied voltage that occurred and ended in a short time less than the specified time. In addition, the resistance change signal is determined by the following formula, based on the difference between the ratio of the voltage drop across the one or more resistive elements to the applied voltage and the filtered value of the ratio of the voltage drop across the one or more resistive elements to the applied voltage: In the above equation, RatioDeviation(t) is a ratio deviation signal, and V ｇｒｉｄ (t) is the voltage drop, V ｂａｓｅ (t) is the applied voltage, teeth, A method characterized by being the value after the filtering process described above.

2. The method according to claim 1, wherein the applied voltage is generated by the traction motor of the vehicle during regenerative braking of the vehicle, and the one or more resistive elements include one or more resistors of the regenerative braking grid.

3. The method according to claim 1, wherein the short-circuit event is identified in response to the resistance change signal exceeding a specified non-zero threshold.

4. The method according to claim 1, wherein the electrical system is a regenerative braking grid.

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