Electrical device for TRS

Abstract

The present disclosure relates to an electrical device 100 for a transport refrigeration system 20. The electrical apparatus 100 includes: a voltage source 120 configured to output a power supply voltage; a load 130 having an input 132 electrically coupled to the output 124 of the voltage source 120; and a controller 190. The controller 190 is configured to: monitor 302 a supply voltage output by the voltage source 120 and a voltage received by the load 130 at an input 132 of the load; determining 304 whether a trigger criterion has been met based on a comparison 343 of the supply voltage to a voltage received by the load 130 from an input 132 of the load 130; and causing 306 the electrical device to enter an error handling mode 400, 500 in response to determining that the trigger criterion has been met.

Description

Technical Field

[0001] The present disclosure relates to an electrical device for a transport refrigeration system, the electrical device comprising a voltage source, a load electrically coupled to the voltage source, and a controller. The present disclosure also relates to a transport refrigeration system comprising the electrical device. Background Art

[0002] As is well known, a transport refrigeration system (TRS) includes electrical devices including at least one electrical load that requires a power supply for operation. The power supply for operating the electrical load may come from, for example, a generator mechanically coupled to a prime mover of a vehicle in which the transport refrigeration system is installed. Otherwise, the power supply for operating the electrical load may come from a power source external to the vehicle (sometimes referred to as "shore power"), from an electrical energy storage device (e.g., a battery), or from other sources (e.g., a solar cell or solar array on the vehicle or TRS).

[0003] Typically, at least one electrical conductor is provided for coupling the electrical load to the rest of the electrical device. However, the electrical coupling to the electrical load typically suffers damage and / or degradation during use due to, for example, the effects of vibrations from other components of the TRS and / or the vehicle in which the TRS is contained, and / or corrosion due to exposure to the atmosphere or contaminants. Ultimately, the electrical coupling may be degraded or otherwise compromised. Such degradation or damage to the electrical coupling may present various risks, such as excessive heat generation within the electrical device, and / or transmission of electrical current to other components of the transport refrigeration system and / or users of the transport refrigeration system.

[0004] It is desirable to provide an electrical device for a transport refrigeration system that is capable of effectively detecting whether an electrical coupling to an electrical load is in a degraded or damaged state. Summary of the invention

[0005] According to a first aspect, there is provided an electrical device for a transport refrigeration system, the electrical device comprising: a voltage source configured to output a supply voltage; a load having an input electrically coupled to the output of the voltage source; and a controller, wherein the controller is configured to: monitor the supply voltage output by the voltage source and a voltage received by the load at an input of the load; determine whether a trigger criterion has been met based on a comparison of the supply voltage and a voltage received by the load from the input of the load; and in response to determining that the trigger criterion has been met, cause the electrical device to enter an error handling mode.

[0006] The controller being configured to cause the electrical device to enter the error handling mode may include the controller being configured to: deactivate the source; and / or cause an alarm to be provided on an interface of the transport refrigeration system.

[0007] The source may be a rectifier, and / or the load may be a DC-DC converter.

[0008] The rectifier may be a synchronous rectifier. The rectifier may have an input configured to receive at least one alternating voltage. The input of the rectifier may be configured to receive a plurality of alternating voltages.

[0009] The controller may be configured to determine that the trigger criterion has been met if a difference between a voltage output by the voltage source and a voltage received by the load is greater than a trigger threshold.

[0010] In addition, the controller can be configured to determine that the trigger criterion has been met if: the difference between the voltage output by the voltage source and the voltage received by the load is greater than the secondary trigger threshold throughout a predetermined trigger period; and the start of the predetermined trigger period is set to the time when the difference between the voltage output by the voltage source and the voltage received by the load is greater than the primary trigger threshold.

[0011] The primary trigger threshold may be greater than the secondary trigger threshold. Alternatively, the primary trigger threshold may be equal to the secondary trigger threshold. The predetermined trigger period may be equal to or greater than 1 second, or equal to or greater than 15 seconds.

[0012] The controller may be configured to: monitor a voltage output by the voltage source by monitoring a signal received from a voltage sensor of the source; and / or monitor a voltage received by the load by monitoring a signal received from a voltage sensor of the load.

[0013] The power supply may be configured to: monitor a voltage output by the voltage source using a voltage sensor of the power supply; and maintain the voltage output by the voltage source within an output voltage tolerance range of an output voltage target value.

[0014] It can be: the output voltage target value is between 48V and 52V; the output voltage tolerance range is between 0.2V and 1.2V; the primary trigger threshold is equal to or greater than 1.5V; and / or the secondary trigger threshold is at least 0.25V lower than the primary trigger threshold.

[0015] The controller may also be configured to: record a number of trigger events, each trigger event corresponding to satisfaction of a trigger condition; in response to determining that the trigger condition has been satisfied, increment the number of recorded trigger events; and cause the electrical device to exit an error handling state based on the number of recorded trigger events.

[0016] If the number of recorded triggering events is less than the event number threshold and the event number threshold is greater than one, the controller may be configured to deactivate the power supply and then reactivate the power supply after a predetermined rest period. The predetermined rest period may be equal to or greater than 1 minute. The predetermined rest period may be equal to or greater than 3 minutes. The predetermined rest period may be equal to or greater than 5 minutes.

[0017] If the number of recorded triggering events is equal to an event number threshold and the event number threshold is greater than one, the controller may be configured to deactivate the power supply and prevent reactivation of the power supply until an unlock signal is received from the interface of the transport refrigeration system. The event number threshold may be equal to or greater than three.

[0018] The controller may be configured to set the number of recorded trigger events to zero if the trigger condition is not met throughout the predetermined trial period. The predetermined trial period may be equal to or greater than 1 hour. The predetermined trial period may be equal to or greater than 2 hours.

[0019] According to a second aspect, there is provided a transport refrigeration system comprising an electrical device according to the first aspect.

[0020] According to a third aspect, a vehicle is provided, the vehicle comprising the electrical device according to the first aspect or the transport refrigeration system according to the second aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A vehicle including a transport refrigeration system is shown;

[0022] Figure 2 is a schematic diagram showing suitable Figure 1 a diagram of a transport refrigeration unit for use with a transport refrigeration system;

[0023] Figure 3 is shown to be suitable for Figure 1 A diagram of an example electrical device for use with a transport refrigeration system;

[0024] Figure 4 It shows the operation Figure 3 A flowchart of an example method of an example electrical device;

[0025] Figure 5 is shown as Figure 4 A flowchart of an example implementation of a process for evaluating triggering criteria as part of the method shown in; and

[0026] Figure 6 is shown as Figure 4 Flowchart of an example implementation of a process of causing an electrical device to enter and then exit an error handling mode as part of the method shown in FIG. DETAILED DESCRIPTION

[0027] Figure 1 A vehicle 10 is shown including a transport refrigeration system 20. Figure 1In the example of FIG. 1 , the transport refrigeration system 20 forms part of a road refrigeration semi-trailer having a structure 22 that supports (or forms) at least one climate controlled compartment 24 configured to be cooled and / or heated by the TRU 110. The structure 22 includes a chassis. The vehicle 10 includes an electrical device 100 that includes various components disposed within a chassis box 105. In some examples, one or more components of the electrical device 100 may be integrated or incorporated into the TRU 110. The structure 22 supports the TRU 110 and the chassis box 105. The vehicle 10 also includes a tractor unit 14 that is removably coupled to the trailer.

[0028] Figure 2 A diagram of an example TRU 110 suitable for use within a vehicle 10 and a transport refrigeration system 20 is schematically shown. The TRU 110 includes a vapor-compression refrigeration circuit 400. The vapor-compression refrigeration circuit 400 includes an evaporator 408 configured to receive heat from a climate-controlled compartment 24 of the transport refrigeration system 20, and a condenser 404 configured to discharge heat to a heat sink 44 (e.g., ambient air outside the climate-controlled compartment 24). To this end, the vapor-compression refrigeration circuit 400 also includes a compressor 402 and an expansion valve 406. Accordingly, the vapor-compression refrigeration circuit 400 can be controlled to remove heat from the climate-controlled compartment 24. It will be apparent to those skilled in the art that the vapor-compression refrigeration circuit 400 can be controlled by any number of suitable control methods. The TRU 110 also includes a plurality of fans 462, 464. In Figure 2 In the example, a first fan 462 is associated with the condenser 404 (e.g., located near the condenser 404) for improving heat transfer at one or more surfaces of the condenser 404, and a second fan 464 is associated with the evaporator 408 (e.g., located near the evaporator 408) for improving heat transfer at one or more surfaces of the evaporator 408.

[0029] Figure 3 A diagram of an example electrical device 100 suitable for use with a transport refrigeration system 20 including a transport refrigeration unit (TRU) 110 is shown. The electrical device 100 may be incorporated into a mobile climate control module including a climate controlled compartment, such as Figure 1, and the transport refrigeration system 20 and climate controlled compartment 24 shown in . Accordingly, the electrical device 100 is generally configured for use in transportation. The electrical device 100 includes a rectifier 120, a DC-DC converter 130, a power distribution unit (PDU) 140, a DC subsystem 150, a plurality of motors 162, 164, an external interface 180, and a controller 190. In use, the rectifier 120 is used as a voltage source, and the DC-DC converter 130 is used as a load. Therefore, the rectifier 120 can be described as a voltage source 120, and the DC-DC converter 130 can be described as a load 130. The external interface 180 can be a user interface capable of providing visual, auditory, and / or tactile information to a user. The controller 190 is generally configured according to the following reference Figure 4 A method is described for operating the electrical device 100 .

[0030] The rectifier 120 has an input side 122 (i.e., input 122) and an output side 124 (i.e., output 124). The input side 122 of the rectifier 120 is configured to receive a plurality of AC voltages from the multi-phase power supply 115, and the output side 124 of the rectifier 120 is configured to output a DC power supply voltage. In this example, the rectifier 120 is a synchronous rectifier (i.e., an active rectifier). Accordingly, each side 122, 124 of the rectifier 120 includes a plurality of power switch components. Each power switch component may include, for example, an insulated gate bipolar transistor (IGBT), a junction gate field effect transistor (JFET), a thyristor, and / or a metal-oxide-semiconductor field effect transistor (MOSFET). Specifically, each power switch component may include a gate turn-off thyristor (GTO) and / or an integrated gate commutated thyristor (IGCT). The power supply 115 may include a generator that is mechanically coupled to a vehicle (e.g., a vehicle) in which the transport refrigeration system 20 is installed. Figure 1 The generator may also be mechanically coupled to or may include an electric motor. The electric motor may be coupled to a power source external to the vehicle (e.g., a "shore" power source) such that the generator is operable when the vehicle 10 is stationary (e.g., not in transit) and / or the prime mover is not operating.

[0031] The rectifier 120 includes a circuit configured to monitor an output voltage V outputted by an output side 124 of the rectifier 120. r The rectifier 120 is configured to use the voltage sensor 128 to monitor the output voltage V r , and by appropriately controlling the multiple power switch components on each side 122, 124 of the rectifier 120 to rMaintained within a predetermined output voltage tolerance range of the output voltage target value. This can be described as a self-regulating function, and thus the rectifier 120 can be described as a self-regulating rectifier 120. Preferably, the output voltage target value is between 48V and 52V, and the output voltage tolerance range is between 0.2V and 1.2V. However, those skilled in the art will appreciate that other output voltage target values ​​and / or output voltage tolerance ranges can be used. For example, the output voltage target value can be between 48.5V and 53.5V (e.g., 51V), and / or the output voltage tolerance range can be between 0% and 5% of the output voltage target value.

[0032] The DC-DC converter 130 has an input side 132 (i.e., input 132) and an output side 134 (i.e., output 134). The DC-DC converter 130 is generally configured to convert an input DC voltage of a first magnitude received at the input side 132 of the DC-DC converter 130 into an output DC voltage of a second magnitude for powering from the output side 134 of the DC-DC converter 130. The ratio of the first magnitude to the second magnitude may be referred to as a conversion ratio of the DC-DC converter 130. The DC-DC converter 130 may include a forward converter (e.g., a buck converter, a split-pi converter, a half-bridge converter, or a full-bridge converter) and / or a flyback converter (e.g., a boost converter, a buck-boost converter, converter, or SEPIC converter).

[0033] The DC-DC converter 130 includes a circuit configured to monitor an input voltage V received at an input side 132 of the DC-DC converter 130 . l The DC-DC converter 130 is configured to monitor the input voltage V using the voltage sensor 138. l (ie, the DC-DC converter monitors the first amplitude), and based on the monitored input voltage V l The conversion ratio of the DC-DC converter 130 is changed so as to control the voltage (i.e., of the second magnitude) provided to the DC subsystem 150 from the output side 134 of the DC-DC converter 130, thereby facilitating normal operation of the DC subsystem 150, which is described in further detail below. This may be described as a self-regulating function, and thus the DC-DC converter 130 may be described as a self-regulating DC-DC converter 130.

[0034] The PDU 140 is generally configured to serve as an interface between the various electrical components of the electrical device 100. The PDU 140 may include at least one short circuit protection device so that if a fault current occurs within the electrical device 100, the PDU can quickly disconnect the components of the electrical device 100. The input side 132 of the DC-DC converter 130 and the output side 124 of the rectifier 120 are both electrically coupled to the PDU 140. Accordingly, the input side 132 of the DC-DC converter 130 is electrically coupled to the output side 124 of the rectifier 120 via the PDU 140 through an appropriate electrical coupling (e.g., an insulated conductor).

[0035] A plurality of motors 162, 164 are also coupled to the PDU 140. Thus, the plurality of motors 162, 164 are coupled to the output side 124 of the rectifier 120 via the PDU 140. Figure 3 In the example of FIG. 1 , the plurality of motors 162, 164 are connected in parallel with each other. However, in other examples, the plurality of motors 162, 164 may be connected in series. Each motor 162, 164 is configured to drive a mechanical device. For example, the mechanical device may be a fan, a pump, or a compressor of the transport refrigeration system 20. Specifically, each motor 162, 164 is configured to drive a corresponding fan 462, 464 associated with the vapor-compression refrigeration circuit 400 of the TRU 110.

[0036] The DC subsystem 150 may include at least one load, at least one voltage source, or a combination of one or more loads and / or one or more voltage sources. Specifically, the DC subsystem 150 may include a battery (which may be used as a load or a voltage source depending on whether the battery is charged or discharged). The DC subsystem 150 may have an operating voltage that may correspond to a nominal voltage or a rated voltage of the battery (if present). In use, the DC-DC converter 130 converts a voltage supplied from the PDU 140 (i.e., a voltage having a first voltage amplitude) to a voltage supplied to the DC subsystem 150 at an operating voltage of the DC subsystem 150 (i.e., a voltage having a second voltage amplitude).

[0037] In the above reference Figure 3 In the depicted example, the electrical device 100 includes a PDU 140 electrically coupled to a rectifier 120 and a DC-DC converter 130. In other examples, the rectifier 120 may be directly electrically coupled to the DC-DC converter 130. In such examples, the electrical device 100 may not include the plurality of motors 162, 164.

[0038] Figure 4is a flow chart illustrating an example method 300 of operating the electrical device 100. As described above, the method 300 is generally implemented by the controller 190. The method 300 includes the process of monitoring (at block 302) the voltage output by the rectifier 120 (at block 302A) and the voltage received by the DC-DC converter 130 (at block 302B). Specifically, the controller 190 is configured to monitor the voltage output by the rectifier 120 (at block 302A) by monitoring the signal received from the rectifier output voltage sensor 128, and to monitor the voltage received by the DC-DC converter 130 (at block 302B) by monitoring the signal received from the converter input voltage sensor 138 described above. During initialization (e.g., startup) of the electrical device 100, the method 300 may include, prior to monitoring (at block 302) the voltage output by the rectifier 120 (at block 302A) and the voltage received by the DC-DC converter 130 (at block 302B), waiting until a predetermined delay period has elapsed to allow the electrical device 100 to stabilize before the method 300 continues as described below. The predetermined delay period may be, for example, at least 1 minute.

[0039] The method 300 also includes a process of evaluating the trigger criteria (at block 304). In response to determining (at block 304) that the trigger condition has not been met, the method 300 returns to the process of monitoring the voltage (at block 302) and the process of evaluating the trigger condition (at block 304), so that the trigger condition repeats until it is determined (at block 304) that the trigger condition has been met. In response to determining (at block 304) that the trigger condition has been met, the method 300 proceeds with the process of causing (at block 306) the electrical device 100 to enter the error handling mode. Figure 5 and 6 The process represented by blocks 304 and 306 is described in further detail.

[0040] Figure 5 It shows that Figure 4 An example implementation of the process of evaluating a trigger criterion is shown at block 304 in FIG. 1 . Typically, the trigger criterion is related to whether an anomaly exists in the electrical coupling between the rectifier 120 and the DC-DC converter 130 .

[0041] The process of evaluating the trigger criteria includes calculating (at block 342) the voltage V output by the rectifier 120 r and the voltage V received by the DC-DC converter 130 l The process of evaluating the trigger criteria then continues by comparing the voltage difference ΔV (as calculated in block 342) with the primary trigger threshold ΔV t1 The action of comparing (at block 343). Primary trigger threshold ΔV t1is selected as the voltage V output by the rectifier 120 r and the voltage V received by the DC-DC converter 130 l The value of the difference between , which indicates that the electrical coupling between the rectifier 120 and the DC-DC converter 130 is in a damaged or degraded state.

[0042] If it is determined as a result of the comparison (at block 343) that the voltage difference ΔV does not exceed the primary trigger threshold ΔV t1 , the process continues to determine (at block 348) that the action that has not met the triggering criteria has not yet been performed, and as described above with respect to Figure 4 The method 300 continues.

[0043] In some examples, if it is determined as a result of the comparison (at block 343 ) that the voltage difference ΔV meets or exceeds the primary trigger threshold ΔV t1 , the process can directly continue to determine (at block 347) that the action of the triggering criterion has been met. That is, the method 300 includes: if the voltage V output by the rectifier 120 is r and the voltage V received by the DC-DC converter 130 l The difference ΔV between them is equal to or greater than the primary trigger threshold ΔV t1 , then it is determined (at block 347) that the trigger criteria are met.

[0044] In other examples, if as a result of the comparison (at block 343 ), it is determined that the voltage difference ΔV exceeds the primary trigger threshold ΔV t1 , the process continues by comparing the voltage difference ΔV (as calculated in block 342) with the secondary trigger threshold ΔV t2 Prior to the act of performing the comparison (at block 345), the act of starting (at block 344) the timing of the predetermined trigger period may continue. Subsequently, if as a result of the comparison (at block 345), it is determined that the voltage difference ΔV exceeds the secondary trigger threshold ΔV t2 , the process continues with the action of determining (at block 346) whether the timing of the predetermined trigger period has ended (ie, whether the predetermined trigger period has passed).

[0045] If it is determined (at block 346) that the timing of the predetermined trigger period has not yet expired, the process returns to comparing the voltage difference ΔV (as calculated in block 342) with the secondary trigger threshold ΔV. t2 The action of comparing (at block 345) causes the repetitive voltage difference ΔV to be equal to the secondary trigger threshold ΔV t2The comparison is performed until it is determined (in block 346) that the timing of the predetermined trigger period has ended. If or when it is subsequently determined (in block 346) that the predetermined trigger period has ended, the process continues with determining (at block 347) the action that has satisfied the trigger criteria. Otherwise, if as a result of the comparison (at block 345) it is found that the voltage difference ΔV does not exceed the secondary trigger threshold ΔV t2 , the process continues to determine (at block 348) that the action of the triggering criteria has not been met, such that if at any point in time during the timing of the predetermined triggering period, the voltage difference ΔV is determined (at block 345) to be equal to or less than the secondary triggering threshold ΔV t2 , the process results in a determination (at block 348) that the trigger criteria have not been met, and as described above with respect to Figure 4 Method 300 continues as shown and described.

[0046] Accordingly, in such an example, method 300 includes: only if the voltage V output by rectifier 120 is greater than or equal to 0 during the entire predetermined trigger period r and the voltage V received by the DC-DC converter 130 l The difference ΔV between them is greater than the secondary trigger threshold ΔV t2 , where the start of the predetermined trigger period is set to when it is determined (at block 343) that the rectifier 120V r Output voltage V r and the voltage V received by the DC-DC converter 130 l The difference ΔV between them is greater than the primary trigger threshold ΔV t1 At the time of , it is determined (at block 347) that the trigger criteria have been met.

[0047] Only when the voltage V output by the rectifier 120 r and the voltage V received by the DC-DC converter 130 l The difference ΔV between them is initially greater than the primary trigger threshold ΔV t1 , and then greater than the secondary trigger threshold ΔV throughout the predetermined trigger period t2 By determining that the trigger criterion has been met only when there is no anomaly in the electrical coupling between the rectifier 120 and the DC-DC converter 130 (which may be referred to as a false positive determination), the probability that the trigger criterion will be determined to have been met by the method 300 can be reduced. The inventors have found that a predetermined trigger period of at least 1 second, and preferably at least 15 seconds, is particularly effective in reducing the probability of a false positive determination that the trigger criterion has been met.

[0048] Preferably, the primary trigger threshold is greater than the secondary trigger threshold. This takes into account the measured voltage V output by the rectifier 120 r and the measured voltage V received by the DC-DC converter 130 l, and thus, when there is an anomaly in the electrical coupling between the rectifier 120 and the DC-DC converter 130 (which may be referred to as a true positive determination), the probability that the trigger criteria will be determined to have been met by the method 300 is increased, and the probability of a false positive determination that the trigger criteria has been met is not significantly increased despite the possible presence of measurement errors. For example, if the output voltage target voltage of the rectifier 120 is between 52V and 48V, and the output voltage tolerance range of the rectifier 120 is between 0.2V and 1.2V, the primary trigger threshold may be equal to or greater than 1.5V (e.g., equal to or greater than 3V), and the secondary trigger threshold may be at least 0.25V less than the primary trigger threshold (e.g., at least 0.5V). The inventors have found that using these values ​​is useful for reducing the error caused by the measured voltage V r and V l It is particularly effective at detecting false positives caused by transients in the circuit.

[0049] Figure 6 It shows that Figure 4 306 of the method 300. The error handling mode may be a first error handling mode (as shown in block 400) or a second error handling mode (as shown in block 500). Typically, the second error handling mode includes various error handling actions that are more destructive to the operation of the transport refrigeration system 20 than the first error handling mode. Therefore, the method 300 is adjusted to generally select the second error handling mode only when there is a high probability that the electrical coupling between the rectifier 120 and the DC-DC converter 130 is in a severely impaired state and / or rapidly degraded or damaged state.

[0050] The process includes selecting whether to enter the first error handling mode or the second error handling mode based on the number of recorded triggering events n, wherein each triggering event corresponds to a unique instance of satisfying the triggering criteria (as determined at block 347). To this end, the process includes an action of recording (at block 362) the number of triggering events n, for example, in a memory of the controller 190 or a memory associated with the controller 190. During initialization (e.g., startup) of the electrical device 100, the number of recorded triggering events may be set to zero, such that n=0, or the number of recorded triggering events may be set equal to the last known value for n stored in the memory of the controller 190 or a memory associated with the controller 190. Recording (at block 362) the number of triggering events includes incrementing the number of recorded triggering events (i.e., increasing the number of recorded triggering events by one) each time it is determined (at block 347) that the triggering criteria have been satisfied. The action of recording (at block 362) the number of triggering events may also include setting the number of recorded triggering events to zero if the triggering criteria have not been satisfied throughout the predetermined trial period. Typically, the predetermined trial period can be defined based on a set of electrical coupling characteristics between the rectifier 120 and the DC-DC converter 130. Specifically, the predetermined trial period can be equal to or greater than 1 hour or equal to or greater than 2 hours. Therefore, a series of independent determinations (at block 347) that the trigger criteria have been met for a considerable period of time will not cause the controller 190 to cause the electrical device 100 to enter the second error handling mode. Such independent determinations can be made as a result of, for example, the transport refrigeration system 20 being in a state that occurs during transportation. Additionally or alternatively, such independent determinations can be made during relatively rare transient events within the electrical device 100, and / or as a result of high levels of electrical noise within the electrical coupling between the rectifier 120 and the DC-DC converter 130 (e.g., as a result of electromagnetic interference).

[0051] The process then continues by comparing the number of recorded trigger events n with the event number threshold n t The act of comparing (at block 364). If the number of recorded trigger events n is not equal to (eg, less than) the event number threshold n t , the process includes causing the electrical device to enter a first error handling mode (see block 400). On the other hand, if the number n of recorded triggering events is equal to (eg, not less than) the event number threshold n t , then the process includes causing the electrical device to enter a second error handling mode (see block 500). Event number threshold n t is usually an integer greater than one. Preferably, the event number threshold n tThis ensures that the electrical device 100 enters the second error handling mode only when a large number of triggering events are recorded, and therefore when there is a high probability that the electrical coupling between the rectifier 120 and the DC-DC converter 130 is in a severely impaired state and / or rapidly damaged or degraded state.

[0052] Both the first error handling mode (represented by block 400) and the second error handling mode (represented by block 500) include the action of deactivating the rectifier 120 (at blocks 410 and 510, respectively). Deactivating the rectifier 120 means that the output side 124 of the rectifier 120 does not output a DC supply voltage.

[0053] Optionally, the first error handling mode (see block 400) further includes: causing (at block 420) an external interface (e.g., as described above with respect to Figure 3 The action of providing an alarm on the external interface 180 described above indicates that the electrical device 100 has entered the first error handling mode.

[0054] The first error handling mode (see block 400) also includes the action of starting (at block 430) the timing of the predetermined rest period before continuing to determine (at block 440) whether the timing of the predetermined rest period has ended (i.e., whether the predetermined rest period has passed).

[0055] If it is determined (at block 440) that the timing of the predetermined rest period has not ended, the process returns to the action of determining (at block 440) whether the timing of the predetermined rest period has ended, and then continues to loop until it is determined (at block 440) that the timing of the predetermined rest period has ended. If it is determined (at block 440) that the timing of the predetermined rest period has ended, the process continues with the action of reactivating (at block 450) the rectifier 120, and then causing the electrical device 100 to exit the first error handling mode. The method 300 then returns to the process of monitoring the voltage (at block 302), and then proceeds to the process of evaluating (at block 304) the triggering criteria, such as Figure 4 If the first error handling mode (see block 400) includes an action causing (at block 420) an alarm to be provided on the interface, then if it is determined (at block 440) that the timing of the predetermined rest period has ended, the process also continues with an action causing (at block 460) the alarm to be removed from the interface.

[0056] The predetermined rest period may be equal to or greater than 1 minute. Alternatively, the predetermined rest period may be equal to or greater than 3 minutes, or equal to or greater than 5 minutes. Using the predetermined rest period in the manner described herein allows any transient conditions (e.g., excessive vibrations from the vehicle 10 containing the transport refrigeration system 20, or local contamination from substances such as water) to dissipate before the rectifier reactivates and causes the electrical device 100 to exit the first error handling mode. In addition, using the predetermined rest period allows any heat generated in the electrical coupling between the rectifier 120 and the DC-DC converter 130 to dissipate before causing the electrical device 100 to exit the first error handling mode. Additionally, use of a predetermined rest period may facilitate resetting of measurement circuits associated with voltage sensors of the rectifier 120 and / or the DC-DC converter 130 before the electrical device 100 exits the first error handling mode and the method 300 returns to the process of monitoring (at block 302) the voltage output by the rectifier 120 (at block 302A) and the voltage received by the DC-DC converter 130 (at block 302B).

[0057] The second error handling mode (see block 500) also includes an action that causes (at block 520) an alarm to be provided on an interface of the electrical device 100 or the transport refrigeration system 20, the alarm indicating that the electrical device 100 has entered the second error handling mode. Specifically, the interface may be a user interface, and the alarm may notify a user that the electrical device 100 has entered the second error handling mode. The alarm may also instruct the user to perform remedial work on the electrical device 100, or instruct the user to schedule remedial work to be performed.

[0058] The second error handling mode (see block 500) also includes an action to determine (at block 540) whether the unlock signal has been received by the controller 190. The alarm provided to the interface (at block 520) may also inform the user that the electrical device 100 will not be allowed to exit the second error handling mode until an unlock input indicating a specific command to exit the second error handling mode is provided to the interface. When the unlock input is provided to the interface, an unlock signal is provided from the interface to the controller 190.

[0059] If it is determined (at block 540) that the unlock signal has not been received, the process returns to the act of determining (at block 540) whether the unlock signal has been received, and then continues to loop until it is determined (at block 540) that the unlock signal has been received. If it is determined (at block 540) that the unlock signal has been received and when it is determined (at block 540) that the unlock signal has been received, the process continues to the act of reactivating (at block 550) the rectifier 120, and the act of causing (at block 560) the alarm to be removed from the interface. The electrical device 100 is then exited from the second error handling mode, and the method 300 returns to the process of monitoring the voltage (at block 302), and then proceeds to the process of evaluating (at block 304) the triggering criteria, such as Figure 4 As such, the method 300 includes preventing the rectifier 120 from being reactivated (at block 550 ) and preventing the electrical device 100 from exiting the second error handling mode unless and until it is determined (at block 540 ) that an unlock signal has been received.

[0060] In summary, the method 300 includes causing the electrical device 100 to reactivate the rectifier 120 and then exit the corresponding error handling mode in a state that differs depending on whether the electrical device 100 has entered the first error handling mode or the second error handling mode (and therefore, differs depending on the number n of recorded triggering events).

[0061] Operating the electrical device 100 according to the method disclosed herein ensures that the electrical coupling between the rectifier 120 and the DC-DC converter 130 can be effectively detected to be in an impaired state and / or in a damaged or degraded state, without the need to include additional (e.g., dedicated) sensor devices within the electrical device 100 for this purpose, such as the sensor devices sampled in the previously considered electrical devices. As a result, the number of parts (e.g., complexity), installation mass, and / or size of the electrical device 100 can be minimized.

[0062] It should be understood that the steps described in the preceding paragraphs may be performed in any suitable order. Figure 4-Figure 6 The processes and actions described herein may be varied, and / or the specific content of each process and / or action may be varied while still achieving the desired control results described above. Although the method 300 is described in the context of the rectifier 120 and the DC-DC converter 130 as the voltage source 120 and the load 130, respectively, it is understood that the method 300 is applicable to other types of voltage sources and loads that form part of the electrical device 100 for the transport refrigeration system 20. Accordingly, unless described with respect to a particular type of feature, all references to the rectifier 120 in this disclosure are equally applicable to other types of voltage sources, and all references to the DC-DC converter 130 in this disclosure are equally applicable to other types of loads.

[0063] The controller described herein may include a processor. The controller and / or processor may include any suitable circuitry to enable the methods described herein and as shown. The controller or processor may include: at least one application specific integrated circuit (ASIC); and / or at least one field programmable gate array (FPGA); and / or a single processor or multi-processor architecture; and / or a sequential (von Neumann) / parallel architecture; and / or at least one programmable logic controller (PLC); and / or at least one microprocessor; and / or at least one microcontroller; and / or a central processing unit (CPU) to perform the methods and / or the functions configured by the controller or processor.

[0064] The controller or processor may include or communicate with one or more memories, wherein the one or more memories store data described herein, and / or store machine-readable instructions (e.g., software) for performing the processes and functions described herein (e.g., determining parameters and executing control routines). The memory may be any suitable non-transient computer-readable storage medium, data storage device, or apparatus, and may include a hard disk and / or solid-state memory (e.g., flash memory). In some examples, the computer-readable instructions may be transmitted to the memory via a wireless signal or via a wired signal. The memory may be a permanent non-removable memory, or may be a removable memory (e.g., a universal serial bus (USB) flash drive). The memory may store a computer program, which includes computer-readable instructions, and when the processor or controller reads the instructions, the method described herein and / or as shown in the figure is executed. The computer program may be software or firmware, or a combination of software and firmware.

[0065] Unless mutually exclusive, features described in relation to any one of the above aspects may be applied to any other aspects after necessary correction. In addition, unless mutually exclusive, any features described herein may be applied to any aspect and / or combined with any other features described herein.

Claims

1. An electrical device (100) for a transport refrigeration system (20), the electrical device comprising: A voltage source (120) configured to output a power supply voltage; a load (130) having an input (132) electrically coupled to the output (124) of the voltage source; and A controller (190), wherein the controller is configured to: monitoring (302) a supply voltage output by the voltage source and a voltage received by the load at the input of the load; determining (304) whether a trigger criterion has been met based on a comparison (343) of the supply voltage with the voltage received by the load from the input of the load; and In response to determining that the triggering criteria have been met, the electrical device is caused (306) to enter an error handling mode (400, 500).

2. The electrical device (100) according to claim 1, wherein: The controller (190) is configured to cause the electrical device to enter the error handling mode (400, 500), including the controller being configured to: deactivating (410, 510) the source; and / or An alarm is caused (420, 520) to be provided on an interface (180) of the transport refrigeration system (20).

3. The electrical device (100) according to claim 1, wherein: The source is a rectifier (120), and / or the load is a DC-DC converter (130).

4. The electrical device (100) according to claim 1, wherein: The controller (190) is configured to determine (304, 343, 347) that the trigger criterion has been met if a difference between a voltage output by the voltage source (120) and a voltage received by the load (130) is greater than a trigger threshold.

5. The electrical device (100) according to claim 1, wherein: The controller (190) is configured to determine (304, 343, 344, 345, 346, 347) that the triggering criterion has been met if: A difference between a voltage output by the voltage source (120) and a voltage received by the load (130) is greater than a secondary trigger threshold throughout a predetermined trigger period; as well as The start of the predetermined trigger period is set to a time when a difference between a voltage output by the voltage source and a voltage received by the load is greater than a primary trigger threshold.

6. The electrical device (100) according to claim 5, wherein: The primary trigger threshold is greater than the secondary trigger threshold.

7. The electrical device (100) according to claim 1, wherein: The controller (190) is configured to: monitoring (302A) a voltage output by the voltage source by monitoring a signal received from a voltage sensor (128, 138) of the source (120); as well as A voltage received by the load is monitored (302B) by monitoring a signal received from a voltage sensor (128, 138) of the load (130).

8. The electrical device (100) according to claim 7, wherein: The source (120) is configured to: monitoring a voltage output by the voltage source using the voltage sensor (128, 138) of the source; as well as The voltage output by the voltage source is maintained within an output voltage tolerance range of an output voltage target value.

9. The electrical device (100) according to claim 1, wherein: The controller (190) is also configured to: recording (362) a number of triggering events, each triggering event corresponding to satisfying the triggering criterion; responsive to determining that the trigger criteria has been met, incrementing a number of recorded trigger events; as well as The electrical device (100) is caused to exit an error handling state based on the number of recorded triggering events.

10. The electrical device (100) according to claim 9, wherein: The controller (190) is configured to deactivate the source (120) if the number of recorded triggering events is less than an event number threshold, the event number threshold being greater than one, and then reactivate the source after a predetermined rest period.

11. The electrical device (100) according to claim 10, wherein: The predetermined rest period is equal to or greater than 1 minute.

12. The electrical device (100) according to claim 9, wherein: The controller (190) is configured to deactivate the source (120) if the number of recorded triggering events is equal to an event number threshold, the event number threshold being greater than one, and to prevent reactivation of the source until an unlock signal is received from an interface (180) of the transport refrigeration system (20).

13. The electrical device (100) according to claim 10, wherein: The event quantity threshold is equal to or greater than three.

14. The electrical device (100) according to claim 9, wherein: The controller (190) is configured to: If the trigger criteria are not met throughout the predetermined trial period, the number of recorded trigger events is set to zero.

15. A transport refrigeration system (20) comprising the electrical device (100) of claim 1.

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