Multifunctional integrated test system

Abstract

A test system for performing a series of electrical tests on a cable is disclosed. The system comprises a test unit, a set of sensors and two circuits. The two circuits are switchably coupled to a common voltage source and selectively electrically coupled to the cable to enable the test unit to perform a corresponding test on the cable.

Description

[0001] CROSS REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of U.S. Patent Application No. 18 / 492,193, filed on October 23, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates generally to test equipment, and more particularly, to a multifunctional integrated test equipment for testing conductors. Background Art

[0004] Commercial aircraft and other applications, including industrial, commercial and residential applications, typically include power distribution systems. Power distribution systems distribute electricity to loads via cables.

[0005] Prior to installation, the cable or a representative sample thereof is subjected to a battery of tests designed to confirm that the cable meets predetermined performance specifications to meet the operational demands of the application. Summary of the invention

[0006] Technical Solution 1. A test system for testing a cable, the cable having a first end and an opposite second end, and also having a conductive element circumferentially surrounded by a first electrical insulation layer, the cable also comprising an unshielded portion and a shielded portion, the shielded portion comprising a first conductive shield circumferentially surrounding the first electrical insulation layer, the first end being electrically coupled to the second end to define a loop, the test system comprising:

[0007] a voltage source configured to supply a first voltage signal;

[0008] a current transformer having a toroidal core defining an aperture, a primary winding and a secondary winding, the primary winding being wound around a branch of the toroidal core, wherein an unshielded portion of the cable may be disposed through the aperture to define the secondary winding;

[0009] a first circuit having a first branch coupled to the voltage source via a first node and electrically arranged in series between the voltage source and an upstream end of the primary winding, the first branch having a first switch, the first circuit further comprising a second branch arranged in series between a downstream end of the primary winding and the voltage source via a second node, the second branch having a second switch, wherein the first circuit receives the first voltage signal when the first switch and the second switch are closed;

[0010] a conductive housing defining an interior space arranged to operably receive a shielded portion of the cable within the interior space, the first conductive shield being coupleable to the conductive housing, the conductive housing being coupleable to an electrical ground;

[0011] a second circuit electrically coupled in parallel with the first circuit, the second circuit coupled to the voltage source via the first node and arranged in series between the voltage source and the secondary winding, the second circuit comprising a third branch having a third switch, the second circuit further comprising a fourth branch arranged in series between the conductive housing and the voltage source via the second node, the fourth branch comprising a fourth switch, wherein when the third switch and the fourth switch are closed, the second circuit receives the first voltage signal;

[0012] a first current sensor configured to sense a first current in the conductive element at an unshielded portion of the cable and to generate a first current sensor signal indicative of a first value of the first current;

[0013] a second current sensor configured to sense a second current through the first node and generate a second current sensor signal indicative of a second value of the second current;

[0014] a third current sensor configured to sense a third current in the shielded portion of the cable and to generate a third current sensor signal indicative of a third value of the third current, the third current being defined by a sum of the first current and a fourth current induced in the first conductive shield;

[0015] a test unit including a first test module and a second test module, the test unit being communicatively coupled to the voltage source to receive therefrom a status signal indicative of a value of the first voltage signal, and also being communicatively coupled to the first current sensor, the second current sensor, and the third current sensor to receive therefrom the first current sensor signal, the second current sensor signal, and the third current sensor signal, respectively;

[0016] wherein, when the third switch and the fourth switch are closed, the first test module is configured to determine a value of the first voltage signal, determine an amplitude of at least one of the first current and the third current, and associate the amplitude of at least one of the first current and the third current with the value of the first voltage signal; and

[0017] Wherein, when the first switch and the second switch are closed, the second test module is configured to determine a difference between the first current and the third current, and to correlate a magnitude of at least one of the first current and the third current with a value of the first voltage signal.

[0018] Technical Solution 2. A testing system according to Technical Solution 1, wherein the first switch and the second switch define a first group of switches, and the third switch and the fourth switch define a second group of switches, wherein the first group of switches is interlocked with the second group of switches so that at a time, only one of the first group of switches or the second group of switches is closed.

[0019] Technical Solution 3. A testing system according to Technical Solution 2, wherein the first group of switches is arranged in a double-pole single-throw configuration, and the second group of switches is arranged in a double-pole single-throw configuration.

[0020] Technical Solution 4. A testing system according to Technical Solution 2, wherein the testing unit is communicatively connected to the first group of switches and the second group of switches to selectively control their respective operations.

[0021] Technical Solution 5. A testing system according to Technical Solution 1, wherein the value of the first voltage signal is limited by amplitude and frequency.

[0022] Technical Solution 6. A testing system according to Technical Solution 1, wherein the voltage source includes a signal generator communicatively connected to an amplifier, and the amplifier is configured to selectively modify a voltage received from the signal generator to define the first voltage signal.

[0023] Technical Solution 7. A testing system according to Technical Solution 1, wherein the conductive housing includes a low-pressure chamber.

[0024] Technical Solution 8. A testing system according to Technical Solution 7, wherein the conductive housing includes a chamber controller communicatively connected to the testing unit.

[0025] Technical Solution 9. A testing system according to Technical Solution 8, wherein the internal space of the conductive housing is selectively pressurized to a predetermined atmospheric pressure, and wherein, when the third switch and the fourth switch are closed, the first test module is also configured to associate the amplitude of at least one of the first current and the third current with the predetermined atmospheric pressure.

[0026] Technical Solution 10. A testing system according to Technical Solution 8, wherein the internal space of the conductive housing is pressurized to a predetermined atmospheric pressure, and wherein, when the first switch and the second switch are closed, the second test module is also configured to associate the amplitude of at least one of the first current and the fourth current with the predetermined atmospheric pressure.

[0027] Technical Solution 11. The test system according to Technical Solution 1, wherein the first test module is a partial discharge test module.

[0028] Technical solution 12. The testing system according to Technical solution 11, wherein a partial discharge event at the first electrical insulation layer causes the fourth current to flow in the first conductive shield.

[0029] Technical Solution 13. A testing system according to Technical Solution 1, wherein the second testing module is an EMI testing module.

[0030] Technical Solution 14. A testing system according to Technical Solution 13, wherein the first current induces the fourth current in the first conductive shielding member.

[0031] Technical Solution 15. A testing system according to Technical Solution 1, wherein the cable also includes a second electrical insulation layer circumferentially surrounding the conductive element and circumferentially surrounded by the first electrical insulation layer, and wherein the shielding part also includes a second conductive shield circumferentially surrounding the second electrical insulation layer, and the second conductive shield is circumferentially surrounded by the first electrical insulation layer.

[0032] Technical Solution 16. The test system according to Technical Solution 1 further includes:

[0033] a first temperature sensor configured to sense a first temperature of the conductive element and to supply a first temperature sensor signal indicative of the first temperature of the conductive element;

[0034] a second temperature sensor configured to sense a second ambient temperature proximate the cable and to supply a second temperature sensor signal indicative of the second ambient temperature; and

[0035] The test unit further includes a third test module, which is communicatively connected to the first temperature sensor and the second temperature sensor to receive the first temperature sensor signal and the second temperature sensor signal therefrom when the first switch and the second switch are closed, and is also configured to determine the first ambient temperature and the second ambient temperature.

[0036] Technical Solution 17. A testing system according to Technical Solution 16, wherein the third testing module is also configured to determine the difference between the first temperature and the second ambient temperature, and to associate the difference between the first temperature and the first ambient temperature with the first current.

[0037] Technical Solution 18. The test system according to Technical Solution 16 also includes a third temperature sensor, which is configured to sense a third temperature of the first conductive shielding component and supply a third temperature sensor signal indicating the third temperature; and wherein the third test module is communicatively connected to the third temperature sensor to receive the third temperature sensor signal therefrom, determine the third temperature, and is also configured to determine the difference between the third temperature and the second ambient temperature, and associate the difference between the third temperature and the second ambient temperature with the first current.

[0038] Technical Solution 19. A testing system according to Technical Solution 18, wherein the internal space of the conductive housing is selectively pressurized to a predetermined atmospheric pressure, and wherein the third test module is also configured to associate the amplitude of the first current with the predetermined atmospheric pressure.

[0039] Technical Solution 20. The test system according to Technical Solution 16 further includes a fourth temperature sensor configured to sense a fourth temperature of the annular core and supply a fourth temperature sensor signal indicating the fourth temperature; and wherein the third test module is communicatively connected to the fourth temperature sensor to receive the fourth temperature sensor signal therefrom, determine the fourth temperature, and is also configured to determine the difference between the fourth temperature and the second ambient temperature, and associate the difference between the fourth temperature and the second ambient temperature with the first current. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In the attached picture:

[0041] Figure 1A is a perspective view of the cable.

[0042] Figure 1B yes Figure 1A The cross section of the cable.

[0043] Figure 1C yes Figure 1A Schematic diagram of a cross section of the shielded part of a cable.

[0044] Figure 1D yes Figure 1A Another aspect of the cross section of the cable.

[0045] Figure 1E yes Figure 1A A cross-section of yet another aspect of the cable.

[0046] Figure 1F yes Figure 1A A cross-section of yet another aspect of the cable.

[0047] Figure 1G yes Figure 1FSchematic diagram of a cross section of the shielded part of a cable.

[0048] Figure 2 is a schematic diagram of a testing system according to aspects described herein.

[0049] Figure 3 is a schematic diagram of another exemplary testing system according to aspects described herein. DETAILED DESCRIPTION

[0050] Aspects of the present disclosure relate to a test apparatus and system, and more particularly, to a multifunctional integrated test apparatus and system for testing insulated conductors such as cables. For purposes of illustration, the present disclosure will be described with reference to testing cables. The present disclosure may be applicable to testing a variety of electrical conductors, including, for example, rigid busbars, and may be used to provide benefits in industrial, commercial, military, and residential applications.

[0051] The word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any implementation described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other implementations. Furthermore, all aspects described herein are to be considered exemplary unless otherwise specifically stated.

[0052] As used herein, the terms "first", "second", and "third", etc., may be used interchangeably to distinguish one component from another, and are not intended to indicate the position or importance of the various components. Unless the context clearly dictates otherwise, the singular forms "one", "an", and "the" include plural references. In addition, as used herein, the term "group" or "group of elements" may be any number of elements, including only one. All directional references (e.g., radial, axial, proximal, distal, upper, lower, upward, downward, left, right, lateral, front, rear, top, bottom, above, below, vertical, horizontal, clockwise, counterclockwise, upstream, downstream, tail, etc.) are used only for identification purposes to help the reader understand the present disclosure, and do not constitute limitations, particularly limitations on the position, orientation, or use of the present disclosure.

[0053] Unless otherwise specified, connection references (e.g., attached, coupled, connected, and joined) are to be interpreted broadly and may include intermediate members between a collection of elements and relative movement between elements. As such, connection references do not necessarily infer that two elements are directly connected and in fixed relation to each other.

[0054] As used herein, an element of "electrical connection", "electrical coupling" or "signal communication" includes an electrical transmission or signal sent, received or communicated to or from these connected or coupled elements. In addition, such electrical connection or coupling may include a wired or wireless connection, or a combination thereof. In a non-limiting example, a connection or disconnection may be selectively configured to provide, enable, disable, etc., to achieve electrical connections between corresponding elements. A non-limiting example electrical connection or disconnection may be enabled or operated by a switch, bus connection logic, or any other energized connector configured to enable or disable a connected downstream electrical load. In addition, although terms such as "voltage", "current" and "electricity" may be used herein, it will be clear to those skilled in the art that these terms may be interrelated when describing aspects of a circuit or circuit operation.

[0055] As used herein, a controllable switch element or "switch" is an electrical device that is controllable to operate or switch between a first operating mode, in which the switch is "closed" to transfer current from the switch input to the switch output, and a second operating mode, in which the switch is "open" to prevent current from being transferred between the switch input and the switch output. In a non-limiting example, a connection or disconnection, such as a connection enabled or disabled by a controllable switch element, can be selectively configured to provide, enable, disable, etc., an electrical connection between corresponding elements.

[0056] As used herein, the term "conductivity" refers to the property of a material that allows an electric charge or electric current to flow through it. Also as used herein, the term "electrical conductor" refers to a material that exhibits a relatively high electrical conductivity (e.g., greater than about 10-7 Siemens / meter (S / m)). Unless otherwise indicated, as used herein, the term "conductive" refers to electrical conductivity, and the term "conductor" refers to an electrical conductor.

[0057] As used herein, the term "electrical insulation" refers to the property of a material that resists the flow of an electric charge or electric current. Also as used herein, the term "electrical insulator" refers to a material that exhibits a low electrical conductivity (e.g., less than about 10-8 Siemens / meter (S / m)). Unless otherwise indicated, as used herein, the term "insulation" refers to electrical insulation, and the term "insulator" refers to an electrical insulator.

[0058] As used herein, the term "ground" or "electrical ground", or "system ground" refers to a reference point in an electrical circuit to which voltage can be measured or referenced. As used herein, "ground" will provide a common return path for electrical current. It should be understood that an element coupled to an electrical ground via a resistive element or impedance is considered to be electrically isolated relative to the electrical ground.

[0059] As used herein, a "controller", such as a "control module", includes a component configured or adapted to provide instructions, control, operation or any form of communication to an operable component to achieve its operation. Such a controller or module may include any known processor, microcontroller or logic device, including but not limited to: a field programmable gate array (FPGA), a complex programmable logic device (CPLD), an application specific integrated circuit (ASIC), a full authority digital engine control (FADEC), a proportional controller (P), a proportional integral controller (PI), a proportional differential controller (PD), a proportional-integral differential controller (PID), a hardware accelerated logic controller (e.g., for encoding, decoding, transcoding, etc.), etc., or a combination thereof. Although described herein as including separate elements, in non-limiting aspects, these controllers and modules may be combined on one or more devices, including general-purpose devices, such as a single processor or microcontroller. Non-limiting examples of such controllers or modules may be configured or adapted to run, operate or otherwise execute program code to achieve an operation or functional result, including performing various methods, functionalities, processing tasks, calculations, comparisons, sensing or measurements, etc., to enable or achieve the technical operations or operations described herein. The operation or functional result can be based on one or more inputs, stored data values, sensed or measured values, true or false indications, etc. Although "program code" is described, non-limiting examples of operable or executable instruction sets may include routines, programs, objects, components, data structures, algorithms, etc. that have a technical effect of performing a specific task or realizing a specific abstract data type. In another non-limiting example, the controller module, regulator module, or integrator module may also include a processor-accessible data storage component, including a memory, whether a transitional memory, a volatile memory, or a non-transient memory. Other non-limiting examples of memory may include random access memory (RAM), read-only memory (ROM), flash memory, or one or more different types of portable electronic memory, such as an optical disk, a DVD, a CD-ROM, a flash drive, a universal serial bus (USB) drive, etc., or any suitable combination of these types of memory. In one example, the program code may be stored in a memory in a machine-readable format accessible to a processor.

[0060] In addition, the memory can store various data, data types, sensed or measured data values, inputs, generated or processed data, etc., which can be accessed by the processor when providing instructions, controls or operations to achieve functions or operational results, as described herein. In another non-limiting example, the control module may include comparing a first value with a second value, and operating or controlling the operation of additional components based on the satisfaction of the comparison. For example, when a sensed, measured or provided value is compared with another value (including a stored or predetermined value), the satisfaction of the comparison can result in an action, function or operation controllable by the controller module. As used herein, the term "satisfaction" or "satisfaction" of the comparison means that the first value satisfies the second value, such as being equal to or less than the second value or within the value range of the second value. It should be understood that this determination can be easily changed to be satisfied by a positive / negative comparison or a true / false comparison. The example comparison can include comparing the sensed or measured value with a predetermined threshold or threshold range.

[0061] In addition, as used herein, sensors may be described as "sensing," "monitoring," or "measuring" a corresponding value. As used herein, sensing, monitoring, or measuring includes determining a value indicative of or associated with a corresponding value, rather than directly sensing or measuring the corresponding value itself. The sensed, monitored, or measured value may also be provided to other components. For example, a signal indicating a particular sensed, monitored, or measured value may be provided to a controller module or processor, and the controller module or processor may perform processing based on the signal to determine a representative value or electrical characteristic representing that value.

[0062] Cables typically undergo acceptance testing performed by users and manufacturers to confirm that the cables meet predetermined performance requirements. For example, typical acceptance tests for cables may include temperature rise tests, partial discharge (PD) tests, and electromagnetic interference (EMI) tests. Each test typically includes subjecting the cable (i.e., the cable under test) to predetermined electrical conditions (voltage, current, etc.) and / or environmental conditions (e.g., atmospheric pressure, temperature, etc.), and measuring the performance characteristics of the cable (e.g., temperature, voltage, current, etc.). The measured performance characteristics may be compared to predetermined thresholds. Testing may be performed according to commercial, industrial, or military standards to determine the acceptability of the cable. In addition, or alternatively, the test may be customized, for example, based on the specific performance requirements of the application.

[0063] A conductor (e.g., a cable) charged to a non-zero potential or conducting current acts as an antenna, which provides energy or radiated emissions to the surrounding environment in the form of near-field electric and magnetic fields (E fields and M fields) and far-field electromagnetic fields (EM fields). The energy from these radiated emissions can be coupled to other nearby conductors and radiated into the environment. The energy can typically be radiated or conducted as electrical noise or electromagnetic interference (EMI), and may interfere with the normal operation of the connection and nearby equipment. Although electrical insulation (e.g., an electrical insulation layer) on or around the cable can mechanically protect the cable from wear and tear, and protect the cable from moisture in the environment, the electrical insulation is transparent to electromagnetic energy and cannot provide protection or shielding from EMI. Therefore, conventional power distribution circuits typically use so-called "shielded cables" or "jacketed cables." Shielded cables typically have a central signal-carrying primary conductor or conductive element, which is disposed within or surrounded by an electrical insulation layer, and is further surrounded by an EMI shielding layer to reduce the effects of EMI. Typically, the shielding layer is conductive and surrounds the insulated primary conductor, and can reduce EMI by reflecting energy, conducting it to the ground, or both.

[0064] Conventional shielded cables typically employ foil shields, braided (or mesh) conductive shields, or a combination thereof. A foil shield is typically a thin layer of conductor (e.g., aluminum) attached to an insulating carrier (e.g., polyester) and circumferentially surrounds an electrical insulation layer that surrounds the electrical insulation layer of a primary conductor or wire. A braided conductive shield is typically a braided mesh formed into a tubular sheath of bare or tinned copper wire that provides a low impedance path (e.g., a short circuit) to ground. In some cases, an unshielded insulated cable may be passed through a braided conductive sheath or shield that may serve as an EMI shield. In some cases, multiple alternating electrical insulation layers and shielding layers may circumferentially surround the primary conductor.

[0065] EMI testing of shielded cables, such as conducted emissions testing, can provide an indication of the effectiveness of the cable shielding. Conducted emissions testing typically involves supplying a predetermined current through the primary conductor of the cable under test within a predetermined frequency range (e.g., 9kHz-300MHz) and detecting undesirable electromagnetic signals (e.g., conducted emissions) emitted from the primary conductor, such as by detecting induced currents in the shielding of the cable's conductive shield. Depending on the test standard or protocol applied, the induced current may be measured in microamperes (μA) and is typically expressed as a logarithmic expression (e.g., dBμA) relative to a frequency spectrum. In some cases, conducted emissions are detected as voltages (e.g., in microvolts (μV)) and are typically expressed as a logarithmic expression (e.g., dBμV) relative to a frequency spectrum.

[0066] Typical conducted emission test equipment or test modules include a power supply (e.g., a voltage source or function generator and amplifier), an EMI receiver (e.g., a spectrum analyzer), a line impedance stabilization network (LISN), an isolation transformer, an RF cable, and a ground cable with a predetermined termination impedance (e.g., 50 ohms). In some cases, the EMI receiver may include a current sensor. The test module typically also includes suitable test software and an automatic data acquisition module, which is arranged to perform various automatic conducted emission tests. Conventional conducted emission tests may include providing current from a power supply to the primary conductor of the cable under test, and scanning using software and an EMI receiver to measure the peak and average values ​​of electromagnetic signals (e.g., voltage and / or current) detected on the shield of the cable under test. The peak and average values ​​of the detected electromagnetic signals are compared with predetermined limits or thresholds specified in the test standard or protocol.

[0067] A partial discharge is when an electrical insulator associated with a conductor cannot withstand the electric field applied to it. The result of this fault is a high-frequency unipolar discharge that only partially bridges the insulation between the conductors, with an accompanying current pulse through and over the insulation from the conductor to ground. The current pulse is relatively short in duration (e.g., microseconds) and low in energy, but can lead to degradation of the electrical insulation. For example, the discharge can attack the insulation internally by heat and ionization. In some cases, the discharge occurs at the surface of the insulator, which can cause the decomposition of air molecules into oxygen (ozone) and nitrogen (nitric oxide). Nitric oxide forms nitric acid, which attacks the insulation from the outside.

[0068] In the case of shielded insulated cables, partial discharges can partially bridge the electrical insulation between the primary conductor and the conductive shield. If partial discharge current pulses are present in the insulation of the cable, a set of radio frequency current pulses of equal magnitude but opposite polarity are conducted on the primary conductor and the conductive shield. The current pulses typically have a relatively high frequency (e.g., megahertz) and a relatively small amplitude (e.g., milliamps). Partial discharge testing of insulated shielded conductors can confirm that the cable insulation is free of partial discharges at a specified frequency and at a specified voltage amplitude.

[0069] Conventional PD test procedures and general evaluation guidelines are generally provided in various industry and military standards. Partial discharge testing of insulated shielded cables typically includes grounding the conductive shield of the cable (e.g., an outer conductive shield) and applying a test voltage to the primary conductor of the cable. The test voltage amplitude and frequency can vary over time. Typical partial discharge tests also include directly or indirectly measuring any discharge current pulses that may occur in the conductive shield due to dielectric breakdown of the electrical insulation layer between the primary conductor and the conductive shield of the cable. For example, in some cases, partial discharge events can be inferred by detecting the discharge current in the conductive shield of the tested cable at various test voltage levels or frequencies. During such a PD test, a test voltage is applied to the primary conductor of the tested cable, and any partial discharge pulses are detected on the shield using a current sensor (e.g., a high frequency current transformer (HFCT) or a radio frequency current transformer (RECT)) and a partial discharge measurement device (e.g., a spectrum analyzer and / or an oscilloscope). The corresponding waveform or characteristics of any discharge current in the conductive shield of the cable can be determined at various test voltage and frequency levels.

[0070] In other cases, a partial discharge current pulse can be inferred or determined based on a measured voltage drop in the test voltage when the discharge occurs. In this case, a conventional pulse generator is typically used to calibrate the test system by correlating the measured voltage drop to a pico-coulomb amount.

[0071] A conventional PD test module includes a variable voltage source (e.g., a pulse generator and an amplifier), one or more current sensors (e.g., an HFCT or RFCT), a partial discharge measurement device (e.g., an oscilloscope and a spectrum analyzer). The PD test module typically also includes suitable test software and an automatic data acquisition module arranged to perform one or more PD tests. Conventional PD testing typically includes a scan using software and a partial discharge detector to characterize the waveform characteristics of any discharge current in the primary conductor or shield or both of the cable under test. The waveform characteristics are analyzed and compared with predetermined limits or thresholds specified in the test standard or protocol.

[0072] The resistance of a cable is inversely proportional to its conductivity and is primarily based on the material (copper, aluminum, etc.) and cross-sectional area (wire gauge) of the cable. The resistance will decrease in direct proportion to the cross-sectional area of ​​the cable. In operation, when conducting current, the temperature of the cable will rise due to its resistance. The magnitude of the temperature rise will be proportional to the cable resistance and the square of the current flowing through the cable.

[0073] Conventional cables have predetermined temperature and ampacity ratings. The ampacity rating is typically the maximum current that the cable can continuously conduct under predetermined conditions (e.g., atmospheric pressure, ambient temperature, etc.) without exceeding its temperature rating. The temperature rating of a cable is typically considered to be the highest temperature that the cable can reach while carrying current at the rated ampacity (e.g., without the insulation melting, oxidizing, or spontaneously igniting). The temperature rating is typically based on the type of insulation and / or jacket used in the cable construction. For example, some conventional cables are typically rated for temperatures ranging from 40 degrees Celsius (°C) to 105°C.

[0074] Temperature rise testing is typically performed to confirm that the cable can meet predetermined temperature ratings and / or current carrying capacity. Conventional temperature rise testing supplies a predetermined electrical test current through the primary conductor of the specific cable being tested and measures the temperature rise (e.g., above ambient temperature) at one or more predetermined locations along the cable. For example, depending on the test standard or protocol applied, the temperature rise may be in the range of about 50°C to about 105°C. In other cases, such as for specialized cables, the temperature range may be higher. In some cases, temperature testing may be performed at a relatively low voltage (e.g., about 5V) that is lower than the rated voltage of the cable being tested.

[0075] Typically, the temperature rise test equipment can be arranged as a test module, which includes a power supply (e.g., a voltage source and / or a current source), a current sensor (e.g., a current transformer) and a set of temperature sensors (e.g., a thermocouple). The temperature rise test module typically also includes suitable test software and an automatic data acquisition module, which is arranged to perform various temperature rises. Conventional temperature rise tests can include supplying an electrical test current of a predetermined amplitude and frequency (e.g., 300A, 2kHz) from a power supply to the primary conductor of the cable under test, and continuously or periodically sensing or measuring the corresponding temperature of the surrounding environment and one or more locations along the cable under test for a predetermined time or until a stable temperature of the cable under test is reached. The maximum measured temperature of the cable under test is compared with the ambient temperature to determine the temperature rise value, and the temperature rise value is compared with a predetermined limit or threshold value specified in the test standard or protocol.

[0076] The acceptance tests discussed above by way of example (e.g., EMI, PD, and temperature rise tests) are typically performed independently of one another using conventional test equipment or instruments (e.g., EMI test modules, partial discharge test modules, temperature test modules, etc.) specifically designed to perform specific tests, or can be performed using general electrical equipment (e.g., power supplies, oscilloscopes, meters, current transformers, sensors, etc.). However, each specific test type requires a specific corresponding circuit and connection arrangement of the cable under test with the corresponding test equipment. As the number of acceptance tests increases, it becomes increasingly time-consuming to reconfigure the test equipment and the cable under test according to the specific arrangement required for each test. Aspects as disclosed herein provide a multifunctional test system and equipment for performing a variety of different tests on cables without the need to reconfigure the test equipment and the cable under test. Aspects as disclosed herein can simplify the testing process of cables. One benefit of aspects as disclosed herein is that the time and effort required to set up and perform multiple different electrical tests of cables is reduced compared to conventional arrangements.

[0077] Although aspects of the present disclosure will be described herein by way of example and for ease of description and understanding, aspects are not limited to EMI, PD, and temperature rise or current carrying capacity testing, and aspects may be used to conduct other types or numbers of tests as desired.

[0078] Reference will now be made in detail to aspects of the present disclosure, one or more examples of which are illustrated in the accompanying drawings. The detailed description uses numerical and letter designations to refer to features in the drawings. Like or similar designations in the drawings and the specification are used to refer to like or similar parts of the present disclosure.

[0079] Figure 1A depicts an isometric view of a cable 150 to be tested, and Figure 1B Shows Figure 1A A cross section of a portion of the cable 150. Also refer to Figure 1A and 1B, the cable 150 has a longitudinal axis 151 and extends from a first diametrically opposed end 150a to a second diametrically opposed end 150b to define an overall length LT of the cable 150. The cable 150 may include an elongated central conductive element 152 (e.g., a copper wire) or primary conductor surrounded by a first electrically insulating layer 154. The first electrically insulating layer 154 may be circumferentially surrounded by a first conductive shield 156 (e.g., a jacket, a braid, etc.). The first conductive shield 156 may define a shielded portion 158 of the cable 150. For example, the first conductive shield 156 may extend longitudinally along a first length L1 of the cable 150 that is less than the overall length LT of the cable 150 to define the shielded portion 158. A second length L2 of the cable 150 at the second end 150b may not include the first conductive shield 156 to define an unshielded portion 157 of the cable 150. The central conductive element 152 at the first end 150a (e.g., at the shielded portion 158) can be electrically connected to the second end 150b (e.g., at the unshielded portion 157), for example, via a terminal block or connector (not shown), to define a conductive ring or annular arrangement (not shown) of the central conductive element 152.

[0080] Figure 1C yes Figure 1A Schematic diagram of a cross-section of a shielded portion 158 of a cable 150. As shown, a primary current (depicted as arrow "Ip") can be operatively supplied or injected to flow in a first direction (e.g., from left to right when viewing the page) in the central conductive element 152. Due to the effects of the radiated electromagnetic field, or partial discharge in the first electrical insulation layer 154, a secondary current (depicted as arrow "Is") having an amplitude less than the primary current Ip can be induced in the first conductive shield 156, which flows in a second direction opposite to the first direction (e.g., from right to left when viewing the page). The total current (depicted as dashed arrow "It") can be measured using a conventional current transformer type current sensor (not shown). Since the directions of the primary current Ip and the secondary current It are opposite, the measured total current It can indicate the difference in amplitude between the primary current Ip and the secondary current It.

[0081] Although for ease of description and understanding, Figures 1A-1C A non-limiting example of a cable 150 having a central conductive element 152 that is a single conductor (eg, wire) is depicted, but is not otherwise limited thereto. Figure 1D Another example of a cross section of a cable 150 to be tested is depicted. Figure 1C The cable 150 with Figure 1B The difference of cable 150 is that Figure 1D The central conductive element 152 includes a set of conductors (eg, twisted conductors).

[0082] As another example, Figure 1E Another example of a cross section of a cable 150 to be tested is depicted. Figure 1E The cable 150 with Figure 1B The difference of cable 150 is that Figure 1E The central conductive element 152 includes a group of conductive elements 152a, 152b, 152c. Each of the conductive elements 152a, 152b, 152c can be surrounded by a corresponding first electrically insulating layer 154. A first conductive shield 156 surrounds each of the conductive elements 152a, 152b, 152c and the corresponding first electrically insulating layer 154.

[0083] In yet other cases, the cable 150 may include multiple insulation layers and conductive shields. Figure 1F , a cross-section of another example of a cable 150 having more than one insulating layer and more than one conductive shield is shown. The central conductive element 152 is surrounded by a first electrically insulating layer 154a. The first electrically insulating layer 154a may be circumferentially surrounded by a first conductive shield 156. However, Figure 1F The cable 150 with Figure 1C The cable 150 of the present invention differs in that a radially inner or second electrically conductive shield 156b is disposed between the first electrically insulating layer 154a and the central conductive element 152. In addition, a radially inner or second electrically insulating layer 154b is disposed between the second electrically conductive shield 156b and the central conductive element 152 and is also arranged to circumferentially surround the central conductive element 52. The first electrically insulating layer 154a circumferentially surrounds the second electrically insulating layer 154 and the second electrically conductive shield 156b. The second electrically conductive shield 156b may circumferentially surround the second electrically insulating layer 154b.

[0084] Figure 1G yes Figure 1F Schematic diagram of a cross-section of a shielded portion 158 of a cable 150. As shown, a primary current Ip can be operably supplied or injected to flow in a first direction (e.g., from left to right when viewing the page) in the central conductive element 152. Due to the influence of the radiated electromagnetic field, or partial discharge in the first electrical insulation layer 154a and / or the second electrical insulation layer 154b, a secondary current Is having an amplitude less than the primary current Ip can be induced in the first conductive shield 156, which flows in a second direction opposite to the first direction (e.g., from right to left when viewing the page). The total current It can be measured using a conventional current transformer type current sensor (not shown). Since the directions of the primary current Ip and the secondary current It are opposite, the measured total current It can indicate the difference in amplitude between the primary current Ip and the secondary current It.

[0085] It should be understood that although for ease of description and understanding, Figures 1A-1FThe central conductive element 152 is depicted as having a generally circular cross-section, but other aspects are not limited thereto. In various cases, the central conductive element 152 can have any desired cross-section, including, for example, elliptical, rectangular, and polygonal, without departing from the scope of the present disclosure. Furthermore, while aspects are discussed herein with respect to testing cables, other aspects are not limited thereto. It is contemplated that aspects as disclosed herein can be arranged to test other electrical conductors, such as busbars and other rigid conductors, without departing from the scope of the present disclosure.

[0086] Figure 2 An exemplary test system 220 according to non-limiting aspects is depicted. For ease of description and understanding, unless otherwise specified herein, reference is made to Figure 1A Description of Cable 150 Figure 2 220 is an exemplary test system, wherein the reference numerals are increased by 100. The test system 220 is arranged to test the cable 250. In non-limiting aspects, the cable 250 may include Figures 1A-1F The cable 250 may be a conventional insulated shielded conductive cable or wire. For example, in one non-limiting aspect, the cable 250 may include an M27500 component wire SAE WC27500 cable. In other non-limiting aspects, the first electrical insulation layer 254 (at Figure 2 The first conductive shield 256 can surround at least a portion of the first electrically insulating layer 254. In non-limiting aspects, the cable 250 can include a cable of any desired size (e.g., American Wire Gauge (AWG)), and can range from, for example, 0000AWG to 26AWG. In some non-limiting aspects, the central conductive element 252 can be a single strand conductor. In other non-limiting aspects, the conductive element 252 can include multiple strands of conductors, each strand having any desired size, without departing from the scope of the present disclosure.

[0087] The test system 220 may include a voltage source 225. For example, in non-limiting aspects, the voltage source may include a signal generator 228a that is communicatively coupled to an amplifier 228b. The signal generator 228a may provide a voltage to the amplifier 228b. The amplifier 228b may be configured to selectively modify the voltage from the signal generator 228a to define a first voltage signal 221. The first voltage signal 221 may have or be defined by a value such as an amplitude, a frequency, a waveform, etc. The voltage source 225 may include a first output terminal 225a and a second output terminal 225b. The first output terminal 225a may be electrically coupled to a first node 231, and the second output terminal 225b may be electrically coupled to a second node 232. The voltage source 225 is configured to supply the first voltage signal 221 across the first output terminal 225a and the second output terminal 225b. In non-limiting aspects, the first voltage signal 221 may be supplied relative to ground. The test system 220 may further include a current transformer 227, a first circuit 241 including a first set of switches 210a, a second circuit 242 including a second set of switches 210b, a set of sensors 260, a test unit 280, and a conductive housing 229. The set of sensors 260 may include a first current sensor 261, a second current sensor 262, and a third current sensor 263. The first set of switches 210a may include a first switch 211 and a second switch 212. The second set of switches 210b may include a third switch 213 and a fourth switch 214.

[0088] The test unit 280 may include a controller 285, a first test module 281, and a second test module 282. For example, in non-limiting aspects, the first test module 281 may be a conventional PD test module configured to perform a PD test of the cable 250, and the second test module 282 may be a conventional EMI test module configured to perform an EMI test of the cable 250.

[0089] The controller 285 can be a conventional controller with a processor, a memory, and a communication module. The processor can be configured to perform various computer-implemented functions and / or instructions (e.g., executing methods, steps, calculations, etc. and storing relevant data in the memory). When executed by the processor, the instructions can cause the processor to perform operations as described herein. The controller 285 can be communicatively coupled to one or more of the voltage source 225, the first test module 281, or the second test module 282, or a combination thereof, and configured to control their respective operations. The controller 285 can be a controller system or a single controller. For example, in non-limiting aspects, the controller 285 can include a first control module 285a, which is communicatively coupled to the first test module 281, and is configured to control the operation of the first test module 281a. In non-limiting aspects, the controller 285 can additionally or alternatively include a second control module 285b, which is communicatively coupled to the second test module 282 and is configured to control the operation of the second test module 282.

[0090] The test unit 280 may include a user interface 290, such as a display or monitor, or be communicatively coupled to the user interface 290. The user interface 290 may be located at a remote location physically separated from the test unit 280. The user interface 290 may include one or more knobs, dials, switches, displays, keyboards, touch screens, monitors, etc., for communicating with a user, such as receiving inputs and providing outputs. The user may input different types of information, including but not limited to test selections, voltage amplitudes, voltage frequencies, waveforms, durations, etc. The test unit 280 may be communicatively coupled to the voltage source 225 via the first communication line 226 and the second communication line 236. For example, the test unit 280 may receive a status signal 226a indicating the value of the first voltage signal 221 from the voltage source 225 via the first communication line 226. In non-limiting aspects, the value of the first voltage signal 221 may indicate the amplitude or frequency of the first voltage signal 211, or both. In non-limiting aspects, the test unit 280 may provide a command signal 236a via the second communication line 236 to trigger the voltage source 225 to adjust or modify the first voltage signal 221.

[0091] The conductive housing 229 defines an interior space 229a and an exterior space 229b. The interior space 229a is sized and arranged to operably receive a shielded portion 258 of the cable 250 therein. The conductive housing 229 may be electrically coupled to the electrical ground 230. An unshielded portion 257 of the cable 250 may be disposed at an exterior 229b of the conductive housing 229. A first conductive shield 256 may be electrically coupled to the conductive housing 229.

[0092] In non-limiting aspects, the conductive housing 229 can be a conventional altitude or low pressure chamber. In these aspects, the conductive housing 229 can be configured to operably provide a controlled atmosphere that can be pressurized to simulate a high altitude (e.g., from 50,000 to hundreds of thousands of feet). For example, the conductive housing 229 can include a pressurization module 219 and a chamber controller 219a. The pressurization module 219 can include a conventional vacuum pump, valves, sensors, etc., which are configured to pressurize the atmosphere within the interior space 229a of the conductive housing 229 to a predetermined atmospheric pressure level. The controller 285 can be communicatively coupled to the test unit 280 via the third communication line 218 and the fourth communication line 217. For example, the test unit 280 can receive a status signal 218a from the chamber controller 219a via the third communication line 218, which indicates the atmospheric pressure value (e.g., 10 pounds per square inch) in the interior space 229a of the conductive housing 229. In non-limiting aspects, the test unit 280 may provide a command signal 217 a via the fourth communication line 217 to trigger the pressurization module 219 to adjust or modify the atmospheric pressure level within the interior space 229 a of the conductive housing 229 .

[0093] The current transformer 227 can have a toroidal core 274 defining an aperture 275, a primary winding 271, and a secondary winding 272. The primary winding 271 can be arranged as a conductive coil wound around a branch 274a of the toroidal core 274. An unshielded portion 257 of the cable 250 can be disposed through the aperture 275. The conductive element 252 at the first end 250a of the cable 250 can be electrically coupled to the conductive element 252 at the second end 250b of the cable 250, for example, via a lug or electrical connector 255, to form a ring or annular structure 250c. When so arranged, the cable 250 can define a secondary winding 272 (e.g., a single-turn secondary winding).

[0094] The first circuit 241 may include a first branch 241a and a second branch 241b electrically connected in series. The first branch 241a is electrically connected to the voltage source 225. For example, the first branch 241a may be electrically connected to the first output terminal 225a via the first node 231. The first branch 241a may be electrically connected in series between the voltage source 225 and the upstream end of the primary winding 271. The first branch 241a may include a first switch 211. The first switch 211 is electrically connected in series with the primary winding 271.

[0095] The first circuit 241 may include a second branch 241b electrically connected in series between the downstream end of the primary winding 271 and the voltage source 225. For example, the second branch 241b may be connected to the second output terminal 225b via the second node 232. The second branch 241b may include a second switch 212. The second switch 212 is electrically connected in series with the primary winding 271. As shown, the first switch 211 and the second switch 212 may be arranged in a double-pole single-throw configuration. In non-limiting aspects, the first switch 211 and the second switch 212 may include any desired switching device (e.g., MOSFET) that can be selectively operated. When the first set of switches 210a (e.g., the first switch 211 and the second switch 212) are closed, the first circuit 241 selectively receives the first voltage signal 221.

[0096] The second circuit 242 is arranged electrically in parallel with the first circuit 241. The second circuit 242 may include a third branch 242a and a fourth branch 242b. The third branch 242a is electrically coupled to the voltage source 225. For example, the third branch 242a may be coupled to the first output terminal 225a via the first node 231. The second branch 241b may be electrically coupled in series between the voltage source 225 and the secondary winding 272 (e.g., the conductive element 252). The third branch 242a may include a third switch 213. The third switch is electrically coupled in series with the secondary winding 272.

[0097] The fourth branch 242b is electrically connected in series between the conductive housing 229 and the voltage source 225. For example, the fourth branch 242b can be connected to the second output terminal 225b via the second node 232. The fourth branch 242b may include a fourth switch 214. The fourth switch 214 is electrically connected in series with the second output terminal 225b and the conductive housing 229. As shown, in non-limiting aspects, the third switch 213 and the fourth switch 214 can be arranged in a double-pole single-throw configuration. In non-limiting aspects, the third switch 213 and the fourth switch 214 can each include any desired switching device (e.g., MOSFET) that can be selectively operated. When the second set of switches 210b (e.g., the third switch 213 and the fourth switch 214) are closed, the second circuit 242 selectively receives the first voltage signal 221.

[0098] The interlock device 215 can be coupled to the first set of switches 210a and the second set of switches 210b. The interlock device 215 interlocks the first set of switches 210a with the second set of switches 210b so that only one of the first set of switches 210a or the second set of switches 210b is closed at a time. In non-limiting aspects, the test unit 280 can be communicatively coupled to the first set of switches 210a or the second set of switches 210b, or both, to selectively control their respective operations, actuations, or switching. For example, the test unit 280 can be communicatively coupled to the first set of switches 210a or the second set of switches, or both, via the fifth communication line 222.

[0099] The first current sensor 261, the second current sensor 262, and the third current sensor 263 are communicatively coupled to the test unit 280. In non-limiting aspects, the first current sensor 261, the second current sensor 262, and the third current sensor 263 may include respective current transformers, such as HFCT or RFCT.

[0100] The first current sensor 261 is configured to sense a first current I1 flowing in a first direction in the conductive element 252 at the unshielded portion 257 and supply a first current sensor signal 261 a indicating a first value (eg, magnitude) of the first current I1 to the test unit 280 .

[0101] The second current sensor 262 is configured to sense the second current I2 passing through the second node 232 and supply a second current sensor signal 262 a indicating a second value (eg, magnitude) of the second current I1 to the test unit 280 .

[0102] The third current sensor 263 is configured to sense the third current I3 flowing through the cable 250 at the shielding portion 258, and supply a third current sensor signal 263a indicating a third value (e.g., amplitude) of the third current I1 to the test unit 280. The third current I3 sensed by the third current sensor 263 may be equal to the sum of the first current I1 flowing through the conductive element 252 in the first direction and the fourth current I4 flowing in the first conductive shield 256 in the second direction opposite to the first direction. For example, in some non-limiting examples, the fourth current may be an induced current caused by an EMI event. In other non-limiting examples, the fourth current I4 may be a current pulse caused by a PD event. The first test module 281 may also be communicatively coupled to the first current sensor 261, the second current sensor 262, and the third current sensor 263 to receive the first current sensor signal 261a, the second current sensor signal 262a, and the third current sensor signal 263a, respectively.

[0103] In operation, aspects of the test system 220 may be arranged to sequentially perform a set of tests, such as a set of acceptance tests, on the cable 250. In non-limiting aspects, the set of tests may include a first test and a second test. For example, in non-limiting aspects, the first test may be a PD test, and the second test may be an EMI test. Each test may include subjecting the cable 250 to predetermined electrical conditions (voltage, current, etc.) and / or environmental conditions (e.g., pressure, temperature, etc.), and measuring performance characteristics (e.g., voltage, current, etc.) of the cable 250. The measured performance characteristics may be compared with predetermined thresholds. Tests may be performed according to commercial, industrial, or military standards to determine the acceptability of the cable 250. In addition, or alternatively, the test may be customized, such as based on specific performance requirements of the application. Although various aspects of the present disclosure are described herein by way of example and for ease of description and understanding, with respect to EMI, PD, and temperature rise tests, the various aspects are not limited thereto, and the various aspects may be used to perform other types or quantities of tests in any order or sequence as desired.

[0104] For example, in the case where the first test includes a PD test of the cable 250, the first switch 211 and the second switch 212 can be switched to an open or closed state, and the third switch 213 and the fourth switch 214 can be switched to a closed or open state. In this way, the first circuit 241 is not operated during the first test, and the second circuit 242 is arranged to be in an operating state. The voltage source 225 can be operated to provide the first voltage signal 221 of a predetermined amplitude and frequency (e.g., 1 kilovolt (kV) at 10 megahertz (MHz) respectively) to the second circuit 242. The voltage source 225 can also be operated to change (e.g., incrementally increase) the amplitude (e.g., from 1 kV to 100 kV in increments of 1000 volts) and frequency (e.g., from 10 MHz to 500 MHz in increments of 10 MHz at each amplitude) of the first voltage signal 221. The voltage source 225 can provide an indication of the amplitude and frequency of the first voltage signal 221 to the first test module 281. The first test module 281 may continuously or periodically monitor the value of the first current I1 corresponding to the corresponding value of the first voltage signal 221. For example, the first test module 281 may determine the value of the first current I1 based on the first current sensor signal 261a received from the first current sensor 261. Additionally or alternatively, the first test module 281 may determine the value of the third current I3 based on the third current signal 263a received from the third current sensor 263.

[0105] In non-limiting aspects, the first test may include testing the cable 250 under a controlled atmosphere, such as pressurizing to a predetermined atmospheric pressure within the interior space 229a of the conductive housing 229. The test unit 280 may determine the atmospheric pressure within the interior space 229a of the conductive housing 229 based on the status signal 218a. The test unit 280 may also be configured to selectively trigger the pressurization module 219 by supplying a command signal 217a to the chamber controller 219a to adjust or modify the atmospheric pressure within the interior space 229a to a predetermined atmospheric pressure level.

[0106] In operation, depending on the amplitude and frequency of the first voltage signal 221, or the atmospheric pressure within the interior space 229a of the conductive housing 229, or a combination thereof, a partial discharge event may occur in the first electrical insulation layer 254 of the cable 250. The partial discharge event may cause the fourth current I4 to flow in the first conductive shield 256, or cause the value of the first current I1 to change, or both. The first test module 281 may also determine the difference between the first current I1 and the third current I3, which indicates the amplitude of the fourth current I4. The first test module 281 may also associate the value (e.g., amplitude and frequency) of the first voltage signal 221 with the determined value of the first current I1 or the fourth current I4 or both. In non-limiting aspects, the first test module 281 may also associate the atmospheric pressure within the interior space 229a of the conductive housing 229 with the determined value of the first current I1 or the fourth current I4 or both. The first voltage signal 221 or the atmospheric pressure or both and the associated values ​​of the first current I1 or the fourth current I4 or both may be compared to a predetermined partial discharge threshold to determine the acceptability of the cable 250 for PD testing.

[0107] In a non-limiting example where the second test includes an EMI test of the cable 250, the first switch 211 and the second switch 212 may be operated or switched to a closed or open state, and the third switch 213 and the fourth switch 214 may be switched to a disconnected or closed state. In this way, the first circuit 241 is operational during the first test, and the second circuit 242 is arranged in a non-operating state. The voltage source 225 may be operated to provide a first voltage signal 221 of a predetermined amplitude and frequency (e.g., 1 kilovolt (kV) at 10 megahertz (MHz) respectively) to the first circuit 241. This causes the first voltage signal 221 to be applied across the primary winding 271, which causes the first current I1 to flow in the secondary winding 272 (i.e., the conductive element 252). The voltage source 225 may provide an indication of the amplitude and frequency of the first voltage signal 221 to the second test module 282. The second test module 282 may continuously or periodically monitor the value of the first current I1 corresponding to the corresponding value of the first voltage signal 221. For example, the first test module 281 may determine a value of the first current I1 based on the first current sensor signal 261 a received from the first current sensor 261 .

[0108] In non-limiting aspects, the second test may include testing the cable 250 under a controlled atmosphere, such as at a predetermined atmospheric pressure within the interior space 229a of the conductive housing 229. The testing unit 280 may determine the atmospheric pressure within the interior space 229a of the conductive housing 229 based on the status signal 218a. The testing unit 280 may also be configured to selectively trigger the pressurization module 219 by supplying a command signal 217a to the chamber controller 219a to adjust or modify the atmospheric pressure within the interior space 229a to a predetermined atmospheric pressure level.

[0109] In operation, depending on the amplitude and frequency of the first current I1, or the atmospheric pressure within the interior space 229a of the conductive housing 229, or a combination thereof, the first current I1 may emit an electromagnetic signal (e.g., a conducted emission) that causes or causes the fourth current I4 to flow in the first conductive shield 256. The second test module 282 may determine the value of the third current I3 based on the third current signal 263a received from the third current sensor 263. The second test module 282 may also determine the difference between the first current I1 and the third current I3, which indicates the amplitude of the fourth current I4. The second test module 282 may associate the value (e.g., amplitude and frequency) of the first voltage signal 221 with the determined value of the fourth current I4. In non-limiting aspects, the second test module 282 may also associate the atmospheric pressure within the interior space 229a of the conductive housing 229 with the determined values ​​of the first current I1 or the fourth current I4 or both. The first voltage signal 221 or the atmospheric pressure within the interior space 229a of the conductive housing 229 or both and the associated values ​​of the first current I1 or the fourth current I4 or both may be compared to predetermined EMI thresholds to determine the acceptability of the cable 250 with respect to EMI testing.

[0110] In non-limiting aspects, the test sequence may additionally or alternatively include a third test. For example, in non-limiting aspects, the third test may be a heat rise test. The third test may include subjecting the cable 250 to predetermined electrical conditions (voltage, current, etc.) and / or environmental conditions (e.g., pressure, temperature, etc.), and measuring the performance characteristics (e.g., temperature rise, etc.) of the cable 250. The measured performance characteristics may be compared with a predetermined threshold. The third test may be performed according to commercial, industrial, or military standards to determine the acceptability of the cable 250. Additionally, or alternatively, the third test may be customized, such as based on specific performance requirements of an application. Although the third test is described herein by way of example and for ease of description and understanding, with respect to the temperature rise test, the various aspects are not limited thereto, and the various aspects may be used to perform other types or quantities of tests in any order or sequence as desired.

[0111] Figure 3 Another exemplary testing system 320 is depicted that is arranged to test a cable 250 according to non-limiting aspects. The cable 250 may be a conventional insulated, shielded, conductive cable or wire. In non-limiting aspects, the cable 250 may include Figures 1A-1F Any one of the cables 150. Figure 3 The test system 320 is similar to Figure 2 The test system 220 has a significant difference in that the test unit 280 of the test system 320 includes a third test module 283. Figure 2 Another significant difference of the test system 220 is that Figure 3In a non-limiting aspect of the present invention, the controller 285 may additionally or alternatively include a third control module 285 c that is communicatively coupled to the third test module 283 and configured to control the operation of the third test module 283 .

[0112] The first current sensor 261 is configured to sense a first current I1 in the conductive element 252 at the unshielded portion 257, and supply a first current sensor signal 261a indicating a first value (e.g., magnitude) of the first current I1 to the test unit 280. The second current sensor 262 is configured to sense a second current I2 passing through the second node 232, and supply a second current sensor signal 262a indicating a second value (e.g., magnitude) of the second current I1 to the test unit 280.

[0113] like Figure 3 As shown in , the sensor group 260 may also include a first temperature sensor 265, a second temperature sensor 266, a third temperature sensor 267, and a fourth temperature sensor 268. In non-limiting aspects, the first temperature sensor 265, the second temperature sensor 266, the third temperature sensor 267, and the fourth temperature sensor 268 may include corresponding thermocouples. The first temperature sensor 265, the second temperature sensor 266, the third temperature sensor 267, and the fourth temperature sensor 268 are communicatively coupled to the third test module 283.

[0114] The first temperature sensor 265 is configured to sense a first temperature of the conductive element 252 (e.g., at the unshielded portion 257 of the cable 250), and supplies a first temperature sensor signal 265a indicating the first temperature of the conductive element 252 to the third test module 283. The second temperature sensor 266 is configured to sense a second temperature of the ambient air near the unshielded portion 257 of the cable 250, and supplies a second temperature sensor signal 266a indicating the second temperature of the ambient air to the third test module 283. The third temperature sensor 267 is configured to sense a third temperature of the first conductive shield 256 of the current transformer 227, and supplies a third temperature sensor signal 267a indicating the third temperature of the first conductive shield 256 to the third test module 283. The fourth temperature sensor 268 is configured to sense a fourth temperature of the toroidal core 274, and supplies a fourth temperature sensor signal 268a indicating the fourth temperature of the toroidal core 274 to the third test module 283. The third test module 283 is communicatively coupled to the first, second, third, and fourth temperature sensors 265, 266, 267, and 268 to receive first, second, third, and fourth temperature sensor signals 265a, 266a, 267a, and 268a, respectively.

[0115] The third test module 283 can be configured to determine a first temperature of the conductive element 252 (e.g., at the unshielded portion 257 of the cable 250) and a second temperature of the ambient air near the unshielded portion 257 of the cable 250 based on the first temperature sensor signal 265a and the second temperature sensor signal 266a, respectively. The third test module 283 can also be configured to determine a temperature rise of the unshielded portion 257 of the cable 250 based on a comparison of the first temperature sensor signal 265a and the second temperature sensor signal 266a. The third test module 283 can also be configured to determine a third temperature of the first conductive shield 256 based on the third temperature sensor signal 267a. The third test module 283 can also be configured to determine a temperature rise of the shielded portion 258 of the cable 250 based on a comparison of the second temperature sensor signal 266a and the third temperature sensor signal 267a. The third test module 283 can also be configured to determine a fourth temperature of the annular core 274 based on the fourth temperature sensor signal 268a. The third test module 283 may also be configured to determine a temperature rise of the annular core 274 based on a comparison of the second temperature sensor signal 266 a and the fourth temperature sensor signal 268 a .

[0116] In a non-limiting example where the third test includes a temperature rise test of the cable 250, the first switch 211 and the second switch 212 can be switched to a closed or open state, and the third switch 213 and the fourth switch 214 can be switched to a disconnected or closed state. In this way, the first circuit 241 is operational during the first test, and the second circuit 242 is arranged in a non-operating state. The voltage source 225 can be operated to provide a first voltage signal 221 of a predetermined amplitude and frequency (e.g., 3 kV at 10 megahertz (MHz) respectively) to the first circuit 241. This causes the first voltage signal 221 to be applied across the primary winding 271, which causes the first current I1 to flow in the secondary winding 272 (i.e., the conductive element 252).

[0117] The third test module 283 may determine a value of the first current I1 corresponding to the value of the first voltage signal 221. For example, the first test module 281 may determine the value of the first current I1 based on the first current sensor signal 261a received by the test unit 280 from the first current sensor 261.

[0118] In non-limiting aspects, the third test may optionally include testing the cable 250 under a controlled atmosphere, such as at a predetermined atmospheric pressure within the interior space 229a of the conductive housing 229. The testing unit 280 may determine the atmospheric pressure within the interior space 229a of the conductive housing 229 based on the status signal 218a. The testing unit 280 may also be configured to selectively trigger the pressurization module 219 by supplying a command signal 217a to the chamber controller 219a to adjust or modify the atmospheric pressure within the interior space 229a to a predetermined atmospheric pressure level.

[0119] In operation, the third test module 283 monitors a second temperature of the conductive element 252 (e.g., at the unshielded portion 257 of the cable 250) based on the first temperature sensor signal 265a. The third test module 283 also monitors a second temperature of the ambient air near the unshielded portion 257 of the cable 250 based on the second temperature sensor signal 266a. The third test module 283 also determines a difference between the first temperature and the second temperature, which indicates a first temperature rise (e.g., exceeding the ambient temperature) of the cable 250. The third test module 283 can correlate the difference between the first temperature and the second ambient temperature with the first current I1.

[0120] In non-limiting aspects, the third test module 283 also monitors a third temperature of the first conductive shield 256 based on the third temperature sensor signal 267a. The third test module 283 also determines a difference between the third temperature and the second temperature, which indicates a second temperature rise (e.g., above the ambient temperature) of the shield portion 258 of the cable 250. The third test module 283 can correlate the difference between the third temperature and the second ambient temperature to the first current I1.

[0121] In non-limiting aspects, the third test module 283 can also monitor a fourth temperature of the ring core 274 based on the fourth temperature sensor signal 268a. The third test module 283 can determine a difference between the third temperature and the second temperature, which indicates a third temperature rise (e.g., above the ambient temperature) of the ring core 274. The third test module 283 can associate the difference between the fourth temperature and the second ambient temperature with the first current I1.

[0122] The third test module 283 may also associate the value (e.g., amplitude and frequency) of the first voltage signal 221 with the determined first, second, and third temperature rises. In non-limiting aspects, the third test module 283 may also associate the atmospheric pressure within the interior space 229a of the conductive housing 229 with the determined first, second, and third temperature rises. The associated values ​​of the first voltage signal 221, the first current I1, the atmospheric pressure within the interior space 229a of the conductive housing 229, or a combination thereof, and the first, second, and third temperature rises, or a combination thereof, may be compared with a predetermined temperature rise threshold to determine the acceptability of the cable 250 with respect to the temperature rise test.

[0123] The disclosure discussed herein provides a solution for multiple testing of conductive cables. A fault detection device can detect and locate faults in wiring before significant energy loss and thus damage occurs. Unlike conventional techniques, aspects as described herein can be implemented without repeatedly disconnecting and reconnecting the tested cable from multiple test modules and instruments.

[0124] Aspects of the present disclosure reduce the workload on maintenance and quality control personnel in determining the performance and / or acceptability of conductive cables.Aspects of the disclosure discussed herein minimize the time and effort typically required to set up and conduct a battery of tests.

[0125] To the extent not yet described, different features and structures of various aspects may be used in combination with each other as desired. A feature may not be shown in all aspects, and this is not meant to be interpreted as it cannot be, but is done for the sake of brevity of description. Therefore, various features of different aspects can be mixed and matched as needed to form new aspects, whether or not the new aspects are explicitly described. All combinations or permutations of the features described herein are covered by the present disclosure.

[0126] This written description uses examples to disclose the subject matter, including the best mode, and also to enable any person skilled in the art to practice the subject matter, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the subject matter is defined by the claims, and may include other examples that occur to those 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 literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.

[0127] The various features, aspects and advantages of the present disclosure may also be embodied in any arrangement of the aspects of the present disclosure, including but not limited to the following technical solutions defined in the enumerated aspects:

[0128] A test system for testing a cable, the cable having a first end and an opposite second end, and also having a conductive element circumferentially surrounded by a first electrical insulation layer, the cable also including an unshielded portion and a shielded portion, the shielded portion including a first conductive shield circumferentially surrounding the first electrical insulation layer, the first end being electrically coupled to the second end to define a loop, the test system comprising: a voltage source configured to supply a first voltage signal; a current transformer having an annular core defining an aperture, a primary winding and a secondary winding, the primary winding being wound around a branch of the annular core, wherein the unshielded portion of the cable can be disposed through the aperture to define the secondary winding; a first circuit having a first node coupled to the voltage source and electrically arranged in series between the voltage source and the primary winding; a first branch between the upstream end of the primary winding and the voltage source, the first branch having a first switch, the first circuit also including a second branch arranged in series between the downstream end of the primary winding and the voltage source via a second node, the second branch having a second switch, wherein when the first switch and the second switch are closed, the first circuit receives a first voltage signal; a conductive housing defining an interior space, which is arranged to operably receive a shielded portion of the cable within the interior space, the first conductive shield can be connected to the conductive housing, and the conductive housing can be connected to an electrical ground; a second circuit, which is electrically connected in parallel with the first circuit, the second circuit is connected to the voltage source via the first node, and is arranged in series between the voltage source and the secondary winding, the second circuit includes a third branch having a third switch, and the second circuit also includes The invention relates to a method for transmitting the first shielded portion of the cable to the conductive housing and generating a first current sensor signal. The method comprises: providing a first current sensor for sensing a first current in the conductive element at an unshielded portion of the cable and generating a first current sensor signal indicating a first value of the first current; a second current sensor for sensing a second current passing through the first node and generating a second current sensor signal indicating a second value of the second current; and a third current sensor for sensing a third current in the shielded portion of the cable and generating a third current sensor signal indicating a third value of the third current, the third current being a function of the first current and the shielded portion of the cable. a sum of a fourth current induced in the first conductive shield; a test unit comprising a first test module and a second test module, the test unit being communicatively coupled to the voltage source to receive therefrom a status signal indicating a value of the first voltage signal, and also being communicatively coupled to the first current sensor, the second current sensor, and the third current sensor to receive therefrom the first current sensor signal, the second current sensor signal, and the third current sensor signal, respectively; wherein, when the third switch and the fourth switch are closed, the first test module is configured to determine the value of the first voltage signal, determine the magnitude of at least one of the first current and the third current, and associate the magnitude of at least one of the first current and the third current with the value of the first voltage signal;and wherein, when the first switch and the second switch are closed, the second test module is configured to determine a difference between the first current and the third current, and to correlate a magnitude of at least one of the first current and the third current with a value of the first voltage signal.;

[0129] A test system according to any preceding clause, wherein the first switch and the second switch define a first group of switches and the third switch and the fourth switch define a second group of switches, wherein the first group of switches is interlocked with the second group of switches such that only one of the first group of switches or the second group of switches is closed at a time.

[0130] A test system according to any preceding clause, wherein the first set of switches are arranged in a double pole single throw configuration and the second set of switches are arranged in a two pole single throw configuration.

[0131] A test system according to any preceding clause, wherein the test unit is communicatively coupled to the first set of switches and the second set of switches to selectively control their respective operations.

[0132] A test system as described in any preceding clause, wherein the value of the first voltage signal is defined by amplitude and frequency.

[0133] The test system of any preceding clause, wherein the voltage source comprises a signal generator communicatively coupled to the amplifier, the amplifier configured to selectively modify a voltage received from the signal generator to define the first voltage signal.

[0134] A testing system according to any preceding clause, wherein the conductive housing comprises a low pressure chamber.

[0135] The test system of any preceding clause, wherein the conductive housing comprises a chamber controller communicatively coupled to the test unit.

[0136] A test system according to any of the preceding clauses, wherein the interior space of the conductive housing is selectively pressurized to a predetermined atmospheric pressure, and wherein, when the third switch and the fourth switch are closed, the first test module is further configured to associate the amplitude of at least one of the first current and the third current with the predetermined atmospheric pressure.

[0137] A test system according to any of the preceding clauses, wherein the interior space of the conductive housing is pressurized to a predetermined atmospheric pressure, and wherein, when the first switch and the second switch are closed, the third test module is further configured to correlate the amplitude of at least one of the first current and the fourth current to the predetermined atmospheric pressure.

[0138] A test system according to any preceding clause, wherein the first test module is a partial discharge test module.

[0139] A testing system as claimed in any preceding clause, wherein a partial discharge event at the first electrically insulating layer causes a fourth current to flow in the first electrically conductive shield.

[0140] The test system according to any preceding clause, wherein the second test module is an EMI test module.

[0141] A testing system as in any preceding clause, wherein the first current induces a fourth current in the first conductive shield.

[0142] A test system according to any of the preceding clauses, wherein the cable further comprises a second electrical insulation layer circumferentially surrounding the conductive element and circumferentially surrounded by the first electrical insulation layer, and wherein the shielding portion further comprises a second conductive shield circumferentially surrounding the second electrical insulation layer, the second conductive shield being circumferentially surrounded by the first electrical insulation layer.

[0143] The test system according to any of the preceding clauses further includes a first temperature sensor configured to sense a first temperature of the conductive element and supply a first temperature sensor signal indicating the first temperature of the conductive element; a second temperature sensor configured to sense a second ambient temperature near the cable and supply a second temperature sensor signal indicating the second ambient temperature; and wherein the test unit also includes a third test module, which is communicatively connected to the first temperature sensor and the second temperature sensor to receive the first temperature sensor signal and the second temperature sensor signal therefrom when the first switch and the second switch are closed, and is also configured to determine the first ambient temperature and the second ambient temperature.

[0144] The test system of any preceding clause, wherein the third test module is further configured to determine a difference between the first temperature and the second ambient temperature, and to correlate the difference between the first temperature and the first ambient temperature to the first current.

[0145] The test system according to any of the preceding clauses further includes a third temperature sensor configured to sense a third temperature of the first conductive shield and supply a third temperature sensor signal indicating the third temperature; and wherein the third test module is communicatively connected to the third temperature sensor to receive the third temperature sensor signal therefrom, determine the third temperature, and is also configured to determine the difference between the third temperature and a second ambient temperature, and associate the difference between the third temperature and the second ambient temperature with the first current.

[0146] The test system of any preceding clause, wherein the interior space of the conductive housing is selectively pressurized to a predetermined atmospheric pressure, and wherein the third test module is further configured to correlate the magnitude of the first current to the predetermined atmospheric pressure.

[0147] The test system according to any of the preceding clauses further includes a fourth temperature sensor configured to sense a fourth temperature of the annular core and supply a fourth temperature sensor signal indicating the fourth temperature; and wherein the third test module is communicatively connected to the fourth temperature sensor to receive the fourth temperature sensor signal therefrom, determine the second temperature, and is also configured to determine the difference between the fourth temperature and a second ambient temperature, and associate the difference between the fourth temperature and the second ambient temperature with the first current.

Claims

1. A test system for testing a cable, the cable having a first end and an opposite second end, and further having a conductive element circumferentially surrounded by a first electrical insulation layer, the cable further comprising an unshielded portion and a shielded portion, the shielded portion comprising a first conductive shield circumferentially surrounding the first electrical insulation layer, the first end being electrically coupled to the second end to define a loop, the test system comprising: a voltage source configured to supply a first voltage signal; a current transformer having a toroidal core defining an aperture, a primary winding and a secondary winding, the primary winding being wound around a branch of the toroidal core, wherein an unshielded portion of the cable may be disposed through the aperture to define the secondary winding; a first circuit having a first branch coupled to the voltage source via a first node and electrically arranged in series between the voltage source and an upstream end of the primary winding, the first branch having a first switch, the first circuit further comprising a second branch arranged in series between a downstream end of the primary winding and the voltage source via a second node, the second branch having a second switch, wherein the first circuit receives the first voltage signal when the first switch and the second switch are closed; a conductive housing defining an interior space arranged to operably receive a shielded portion of the cable within the interior space, the first conductive shield being coupleable to the conductive housing, the conductive housing being coupleable to an electrical ground; a second circuit electrically coupled in parallel with the first circuit, the second circuit coupled to the voltage source via the first node and arranged in series between the voltage source and the secondary winding, the second circuit comprising a third branch having a third switch, the second circuit further comprising a fourth branch arranged in series between the conductive housing and the voltage source via the second node, the fourth branch comprising a fourth switch, wherein when the third switch and the fourth switch are closed, the second circuit receives the first voltage signal; a first current sensor configured to sense a first current in the conductive element at an unshielded portion of the cable and to generate a first current sensor signal indicative of a first value of the first current; a second current sensor configured to sense a second current through the first node and generate a second current sensor signal indicative of a second value of the second current; a third current sensor configured to sense a third current in the shielded portion of the cable and to generate a third current sensor signal indicative of a third value of the third current, the third current being defined by a sum of the first current and a fourth current induced in the first conductive shield; a test unit including a first test module and a second test module, the test unit being communicatively coupled to the voltage source to receive therefrom a status signal indicative of a value of the first voltage signal, and also being communicatively coupled to the first current sensor, the second current sensor, and the third current sensor to receive therefrom the first current sensor signal, the second current sensor signal, and the third current sensor signal, respectively; wherein, when the third switch and the fourth switch are closed, the first test module is configured to determine a value of the first voltage signal, determine an amplitude of at least one of the first current and the third current, and associate the amplitude of at least one of the first current and the third current with the value of the first voltage signal; and Wherein, when the first switch and the second switch are closed, the second test module is configured to determine a difference between the first current and the third current, and to correlate a magnitude of at least one of the first current and the third current with a value of the first voltage signal.

2. The test system according to claim 1, wherein: The first switch and the second switch define a first set of switches and the third switch and the fourth switch define a second set of switches, wherein the first set of switches is interlocked with the second set of switches such that only one of the first set of switches or the second set of switches is closed at a time.

3. The test system according to claim 2, wherein: The first set of switches are arranged in a double pole single throw configuration and the second set of switches are arranged in a double pole single throw configuration.

4. The test system according to claim 2, wherein: The test unit is communicatively coupled to the first set of switches and the second set of switches to selectively control respective operations thereof.

5. The test system according to claim 1, wherein: The value of the first voltage signal is defined by amplitude and frequency.

6. The test system according to claim 1, wherein: The voltage source includes a signal generator communicatively coupled to an amplifier, the amplifier configured to selectively modify a voltage received from the signal generator to define the first voltage signal.

7. The test system according to claim 1, wherein: The conductive housing includes a low pressure chamber.

8. The test system according to claim 7, wherein: The conductive housing includes a chamber controller communicatively coupled to the test unit.

9. The test system according to claim 8, wherein: The interior space of the conductive housing is selectively pressurized to a predetermined atmospheric pressure, and wherein, when the third switch and the fourth switch are closed, the first test module is further configured to correlate a magnitude of at least one of the first current and the third current to the predetermined atmospheric pressure.

10. The test system according to claim 8, wherein: The interior space of the conductive housing is pressurized to a predetermined atmospheric pressure, and wherein, when the first switch and the second switch are closed, the second test module is further configured to correlate the magnitude of at least one of the first current and the fourth current to the predetermined atmospheric pressure.

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