HOST SYSTEM WITH AC CHARGING INPUT AND METHOD FOR IDENTIFYING AN ELECTRICAL DEVICE CONNECTED TO IT

Abstract

A method (100) for detecting an externally connected AC electrical device, (14A, 14B) via a host system (10) with a rechargeable energy storage system, RESS, (12) and an AC charging input (20) connected to the RESS (12), the method (100) comprising: while the AC charging input (20) is electrically connected to the AC electrical device (14A, 14B) via a vehicle-to-live (V2L) load connector and a V2L cable set forming a V2L connection, or via a jump-start charging cable set and an EVSE charging cable set, Electric Vehicle Service Equipment, forming a jump-start charging connection, detecting a control pilot voltage and a proximity voltage at a respective pilot voltage terminal and proximity voltage terminal of the AC charging input (20);When the control pilot voltage is zero volts, evaluate, via the controller (50), whether entry conditions are met, wherein the entry conditions indicate a request by a user of the host system (10) to discharge current from the RESS to the AC electrical device (14A, 14B); receive, via the controller (50), a modulated voltage signal from the V2L connection or from the jump-start charging connection in response to the entry conditions, wherein the modulated voltage signal is a predetermined signal variation of the proximity voltage and / or the control pilot voltage; identify, via the controller (50), the AC electrical device (14A, 14B) as an identified device, including comparing the modulated voltage signal with an expected voltage, which indicates identity of the AC electrical device;and discharging electrical energy from the RESS (12) to the identified device via the V2L connection or the jump-start charging connection when the modulated voltage signal matches the expected voltage, wherein the identified device is a 240 V AC auxiliary device and wherein the discharge of electrical power from the RESS (12) to the identified device occurs via the jump-start charging connection when the modulated voltage signal matches the expected voltage, further comprising: monitoring a current state of charge, SOC, of ​​the RESS (12) via the controller (50);and automatic interruption of the electrical power delivery from the RESS (12) to the identified device when the current SOC is below a SOC threshold, wherein the host system (10) is a host vehicle, the RESS comprises a high-voltage traction battery pack of the host vehicle, and the AC charging input (20) is an EVSE charging input, and wherein the current SOC is a current SOC of the traction battery pack, further comprising: determining, via the controller (50), a distance between the host vehicle (10) and a nearest charging station or destination; and automatically adjusting the SOC threshold based on the distance and the current SOC.

Description

The present disclosure relates to a host system with an alternating current (AC) charging input and, in particular, to associated methods for automatically detecting and identifying an AC electrical device connected to the charging input. The automatic detection and identification of the connected electrical device, which, as explained herein, may have various designs and voltage requirements, is performed before current is discharged from a rechargeable energy storage system (RESS) of the host system to the connected electrical device. In the various exemplary embodiments described herein in detail, the host system is a motor vehicle or other mobile platform with an electrified powertrain that draws current from the RESS.For the sake of simplicity, the host system is hereby referred to interchangeably as the host vehicle, without limiting the present disclosure to mobile systems in general or motor vehicles in particular. As is known in the prior art, the automatic charging of the electrochemical battery cells of a traction battery pack, which is a key component of the aforementioned RESS, can be carried out using an offboard charging station for electric vehicle supply equipment (EVSE). For this purpose, the host vehicle is typically equipped with the aforementioned AC charging input, which is located at an accessible point on the vehicle's body. The charging terminals of the charging input are configured to accept and engage the corresponding charging pins of an EVSE charging plug, with the plug being connected to the aforementioned charging station via an electrical cable.In North America, such a connector is typically a five-pin SAE J1772 charging connector, where the five pins correspond to a terminal for line 1 (L1), a terminal for line 2 / neutral (L2 / N), a ground terminal (G), a terminal for 0-12 V control voltage (CP), and a terminal for 0-5 V proximity voltage (PRX). However, other pin configurations may be used in other geographic regions, depending on the respective charging standards. During routine battery charging, when the host vehicle's traction battery is actively being charged, the host vehicle remains securely connected to the external EVSE charging station via the interlocked engagement of the EVSE charging plug and the AC charging input counterstructure. However, when active charging is complete, or when the battery is not being discharged to power an onboard electrical load, the electrical energy stored in the individual battery cells of the battery / RESS remains available as a potential power source. If an external AC electrical device is connected to the charging input, however, the host vehicle does not know the identity of the connected device, which in turn complicates subsequent decisions regarding power output control. DE 10 2016 214 050 A1 relates to an arrangement comprising a motor vehicle, including a battery, a charging port and a charging device connected between the battery and the charging port, and a connecting means comprising a first coupling which is connected or connectable to the charging port of the motor vehicle, and a second coupling which can be connected to an energy sink for the transfer of power from the motor vehicle to the energy sink. DESCRIPTION The object of the invention is to enable a safe and range-optimized external energy output from a vehicle-mounted high-voltage energy storage device to power-intensive AC consumers, while preventing harmful deep discharge of the energy storage device. This object is achieved by the subject matter according to claim 1. The hardware and software solutions provided herein enable the automatic detection and identification of an externally connected alternating current (AC) electrical device of one of two types: (1) a vehicle-to-live (V2L) charging connection box with an associated V2L cable set and end connectors that together form a V2L connection, or (2) a jump-start charging cable set that is connected at one end to an EVSE charging cable set, the two cable sets and their end connectors together forming a jump-start charging connection. The resident / own control logic for carrying out the present method resides on an electrified host system, which may itself be a battery electric vehicle (BEV) or a hybrid electric vehicle (HEV) in the non-limiting embodiments described below, or another mobile or stationary system with its own resident rechargeable energy storage system (RESS).The RESS of the host system is embodied here as a multi-cell high-voltage traction battery pack with a lithium-ion, nickel-metal hydride, or other application-appropriate electrochemical battery chemistry. AC discharge accessories, which can be plugged into the V2L load terminal box in various conceivable configurations, can be a nominal 120 V multi-phase device, while the EVSE charging cable set and its end connectors, used in an exemplary "jump-start" scenario, are typically configured as a higher-voltage device, such as a nominal 240 V AC device. In the "jump-start charging" scenario, the jump-start charging cable set and the EVSE charging cable set are ultimately used to transfer the discharged energy from the host vehicle's RESS to a depleted RESS of a second electric vehicle, such as a different BEV than the host vehicle.As a result, when a plug connection is established with the AC charging input of the host vehicle, an onboard controller of the host vehicle quickly distinguishes between the connection of an offboard EVSE charging station, the aforementioned V2L load connection box, and the jump-start charging cable set and EVSE charging cable set, with the latter option corresponding to the jump-start use case mentioned above. The present teaching can readily be applied on board an electrified motor vehicle as well as on board battery-powered watercraft, aircraft, rail vehicles, mobile platforms, robots, etc. Since the mobility of the system is not strictly necessary within the scope of this disclosure, stationary systems, such as power plants, can also be controlled according to this teaching. However, for the sake of illustration and to demonstrate particularly advantageous applications, the present teaching is explained in connection with a rechargeable battery electric vehicle (BEV), without limiting the teaching to such a configuration. For this reason, the host system of this disclosure is referred to interchangeably here as a host vehicle, as mentioned elsewhere above. The solutions described here are designed for specific use cases where the host vehicle's onboard rotating electric machine is not generating active torque and the host vehicle's RESS is not being charged. During such times, the electrical energy stored in the host vehicle's RESS battery cells remains available to power other functions. For example, at certain times, it may be useful for a host vehicle user to be able to connect one of the AC electrical devices described above to the AC charging input and, after successful identification of the connected device using the described procedure, supply power from the RESS to the externally connected AC electrical device. A clear application scenario is that of "tailgating" or camping. In such a scenario, the user might want to temporarily power any number of AC discharge accessories, such as an electric grill, an oscillating fan, lights, a radio, or a television. Such AC discharge accessories could be plugged into the V2L load connection box via the V2L cable set and end connectors, and then powered via the host vehicle's RESS. Similarly, a situation might arise where the user of another / secondary electric vehicle experiences a discharged battery state requiring a jump start. The host vehicle user can assist in this specific use case by connecting the host vehicle's AC charging input to a corresponding AC charging input on the secondary electric vehicle.This connection is established here using a dedicated jump-start charging cable set and an EVSE charging cable set, which are connected end-to-end. In each of these exemplary use cases, an electrical connection is first established between the AC charging input of the power-supplying host vehicle and the external AC electrical device, whose identity is then automatically determined by a control unit in the host vehicle before power is delivered from the RESS to the connected AC electrical device. Once the external electrical connection is established, the present hardware- and software-based control strategy, together with a Vehicle Integrated Control Module (VICM) or another suitable onboard controller of the host vehicle, enables automatic differentiation between different types of AC electrical devices. The identification of each device is performed automatically using existing voltage signals that are selectively modulated or varied, as described herein, where the approach voltage and the pilot voltage are two possible candidate voltage signals that are evaluated by the controller within the scope of this disclosure. According to an exemplary embodiment, a method for detecting an externally connected AC electrical device via a host system with a RESS and an AC charging input connected thereto, while the AC charging input is electrically connected to the electrical device, comprises detecting a control pilot voltage and a proximity voltage at the respective pilot voltage and proximity voltage terminals of the AC charging input. If the control pilot voltage is zero volts, the method includes evaluating, via the controller, whether certain input conditions are met. The input conditions in this particular embodiment indicate a user's desire to supply power from the host system's RESS to the AC electrical device. In response to the fulfillment of the input conditions, the controller receives a modulated voltage signal from an EVSE charging connector of an EVSE charging cable set, or from a similar connector of a V2L cable set connected to the aforementioned V2L load terminal, depending on the connection. The modulated voltage signal is a predetermined variation of the proximity voltage and / or the control pilot voltage. The method then involves comparing the modulated voltage signal, via the controller, to an expected voltage, indicating the identity of the external electrical load.The electrical power delivered by the RESS to the external AC electrical device is then released when the modulated voltage signal matches the expected voltage. A host system is also disclosed herein. In one disclosed embodiment, the host system comprises a RESS with a plurality of battery cells, an AC charging input, a bidirectional inverter connected to the RESS, a measurement circuit, and a controller configured to perform the present method. The AC charging input has five voltage terminals, including a first-line voltage terminal (L1), a second-line / neutral voltage terminal (L2 / N), a ground voltage terminal (G), a control voltage terminal (CP), and a proximity voltage terminal (PRX). The bidirectional inverter is connected to the RESS, the L1 voltage terminal, and the L2 / N voltage terminal and is configured to convert a DC voltage from the RESS to an AC voltage and vice versa, if required.The measuring circuit is connected to the voltage terminals G, CP and PRX and is configured to measure a CP voltage and a PRX voltage. The above summary does not represent every embodiment or aspect of this disclosure. Rather, the features and advantages mentioned above, as well as other features and associated advantages of this disclosure, will be readily apparent from the following detailed description of illustrative examples and modes of implementation of the present disclosure when considered in conjunction with the accompanying figures and the attached claims. Furthermore, this disclosure expressly includes combinations of the elements and features described above and below. BRIEF DESCRIPTION OF THE FIGURES Fig. 1 is a schematic representation of a representative electrified host system in the form of a battery-electric vehicle configured to automatically identify an externally connected AC electrical device and subsequently supply power to the connected device according to the disclosure. Fig. 2 is a schematic perspective view of a representative charging plug for an electric vehicle supply unit (EVSE) according to one embodiment and of voltage connections used by an onboard controller of the host system shown in Fig. 1 when carrying out the present method. Fig. 3 and Fig.Figure 4 shows alternative circuit topologies for implementing an exemplary use case where the externally connected AC electrical device is an AC discharge accessory, with the connection made via an intermediate Vehicle-to-Live (V2L) load connector and associated V2L cable set. Figure 5 is a schematic electrical circuit topology for implementing a jump-charge use case where the externally connected AC electrical device comprises an EVSE charging connector and associated cable set. Figure 6 is a logic flow diagram describing one possible embodiment of a control method for use on board the host system shown in Figure 1. DETAILED DESCRIPTION The present disclosure can be realized in many different forms. Representative examples of the disclosure are illustrated in the drawings and are described here in detail as non-restrictive examples of the disclosed principles. For this purpose, elements and limitations described in the sections “Summary”, “Introduction”, “Description”, and “Detailed Description”, but not expressly included in the claims, should not be incorporated into the claims, either individually or collectively, either by implication, by inference, or otherwise. For the purposes of this description, the use of the singular, unless expressly excluded, includes the plural and vice versa; the terms "and" and "or" apply in both the subjunctive and disjunctive moods; "every" and "all" mean "everyone and all"; and the words "including," "containing," "comprehensive," "with," and the like mean "including without limitation." Furthermore, words of approximation such as "about," "almost," "essentially," "generally," "approximately," etc., may be used here to mean "at, close to, or almost at" or "within 0-5% of" or "within acceptable manufacturing tolerances," or logical combinations thereof. With reference to the figures, in which the same reference numerals refer to the same features in the different views, Fig. 1 schematically depicts an electrified host system 10 in the representative / non-restrictive form of a motor vehicle with road wheels 13. In other embodiments, the host system 10 can be a different type of mobile platform, e.g., a watercraft, an aircraft, a rail vehicle, etc. Alternatively, the host system 10 can be stationary, in which case, in its wide range of possible mobile or stationary embodiments, the host system 10 comprises a multi-cell rechargeable energy storage system (RESS-1) 12, the energy of which is discharged situationally upon successful detection of an AC electrical device 14A or 14B, as described below. For the sake of descriptive consistency, the host system 10 is referred to hereafter, without restriction, as the host vehicle 10. In particular, the electrical energy stored in a plurality of electrically interconnected electrochemical battery cells 12C (see Fig. 3-5) of the RESS 12 could be made available for use outside the vehicle on a situational basis when the external AC electrical device 14A or 14B is powered at the discretion of a user of the host vehicle 10. For example, within the scope of the present disclosure, the RESS 12 located on board the host vehicle 10 could be selectively connected to the AC electrical device 14A or 14B. The electrical device 14A can be configured as one or more different 120 V AC nominal discharge accessories 15A, 15B, or 15C. In contrast, the electrical device 14B can be configured as a nominal 240 V or other higher voltage AC discharge device, ultimately connected to a RESS 112 (RESS-2), e.g.,an electrified secondary vehicle 10A is coupled. Thus, the connected AC electrical devices 14A and 14B, when powered by the RESS 12, would have different loads and therefore require different power control strategies. When no power is being drawn, the RESS 12 of the main vehicle 10 can be recharged by an external EVSE (Electric Vehicle Supply Equipment) charging station 16. Variations of the EVSE charging station 16 are capable of outputting an AC charging voltage (VAC), and possibly a DC charging voltage (not shown), or both, as is well understood in the art of EV charging. The charging of an electric vehicle is carried out according to country-specific standards, with SAE J1772 being the relevant North American standard that specifies the required electrical hardware and communication protocols to be used when performing a vehicle charging operation. While J1772 is used here for the purpose of illustrating the present teaching and the associated voltage terminal / pin configurations within the non-restrictive exemplary context of motor vehicle charging, i.e., where the electrified host system 10 is a motor vehicle and is therefore referred to below as host vehicle 10, the present control strategy can be adapted for use with other relevant standards, such as, but not limited to, the Combined Charging System (CCS), CHAdeMO, etc. With regard to the exemplary AC electrical device 14A, relevant examples include any number of devices that a user of the host vehicle 10 might occasionally wish to power when the host vehicle 10 is not in operation. In the camping scenarios mentioned above, for example, the user might draw power from the RESS 12 to operate a television, a reading lamp, or a hairdryer, as shown for the representative AC accessories 15A, 15B, and 15C. Other possible embodiments of the AC electrical device 14A include radios, oscillating fans, refrigerators, heaters, electric grills, and the like; therefore, the examples shown in Fig. 1 are representative of the present approach and are not limiting. For this purpose, a first end connector 18C-1 is located at a first distal end E1 of a vehicle-to-live (V2L) cable set 18, e.g., a portable electrical connector J1772 and the associated electrical wiring, as shown. Such a configuration can be used to selectively connect sockets or terminals of an EVSE / AC charging input 20 of the host vehicle 10 to a V2L load connection box 22 configured as described herein. The electrical device 14A can be plugged into a corresponding AC socket 24 of the V2L load connection box 22, either directly or using an extension cable (not shown), as indicated by the double arrow CC.Such a V2L cable set 18 comprises a first and a second distal end E1 and E2, wherein the first distal end E1 is connected to the AC charging input 20 via a first terminal connector 18C-1, as indicated by the double-headed arrow AA, and the distal end E2 is connected to a corresponding terminal block 25 of the V2L load connection box 22 via a second terminal connector 18C-2. In this way, electrical power from the RESS 12, which is located on board the host vehicle 10, can be selectively used to power the connected electrical device 14A via the intermediate V2L load connection box 22 and the associated V2L cable set 18. Another connection scenario is that of jump-start charging, which occurs when the user of the host vehicle 10 wants to connect the AC charging input 20 to a counterpart AC charging input 200 located on the second vehicle 10A. In this case, two different charging cable sets can be used: a special jump-start charging cable set 19 and an EVSE charging cable set 180, each with a first and second distal end E1 and E2, respectively. The first distal end E1 of the jump-start cable set 19 is plugged into the AC charging input 20 of the host vehicle 10, while the second distal end E2 of the same cable set 19 is connected to the second distal end E2 / terminal connector 180C-2 of the EVSE charging cable set 180.The first distal end E1 of the EVSE charging cable set 180 is then connected to the AC charging input 200 of the secondary vehicle 10A to complete the connection between the host vehicle 10 and the secondary vehicle 10A, with the jump-start cable set 19 in this case functioning as or as part of the electrical AC device 14B. The alternative connection of the RESS 12 to the electrical consumers 14A or 14B is schematically indicated in Fig. 1 by the triple arrow BB. For both applications, an on-board control unit 50 of the host vehicle 10, e.g.A vehicle-integrated control module or VICM, configured to detect and identify the AC electrical device 14A or 14B, and subsequently limits the discharge of the RESS 12 in accordance with predefined or user-selected and / or calculated state-of-charge (SOC) limits, which may be set via an enable signal (arrow ENBL) from a mobile device 11 and / or a vehicle-integrated device 17. This capability ensures that sufficient SOC remains to reach the user's next destination and / or the nearest EVSE charging station 16. To enable user-selectable functions, possibly including the selective enablement of the execution of a method 100 of Fig.6. By means of the controller 50 and / or the selection of the aforementioned SOC thresholds to apply to a specific discharge operation, aspects of the procedure 100 can be encoded as a computer-executable application (“App”) 29, which the user can access via the mobile device 11, e.g., a smartphone, as shown, and / or by accessing a display screen (DISP) 170 of the integrated device 17 of the host vehicle 10, such as a touchscreen of an infotainment or navigation system. For this purpose, the input conditions for executing the procedure 100, or for executing the procedure 100 in a desired manner, can include the receipt of the enable signal (arrow ENBL) by the controller 50. Still referring to Fig. 1, the controller 50 receives input signals (arrow CCIN) and sends output signals (arrow CCO) during the execution of the method 100. Accordingly, the controller 50 is configured to accurately detect the above connection of the AC electrical device 14A or 14B to the AC charging input 20 of the host vehicle 10 using the method 100, an unlimited / exemplary embodiment of which is shown in Fig. 6 and described below. Upon successful detection, the controller 50 discharges electrical power from the RESS 12 to the identified AC electrical device 14A or 14B. For the purpose of carrying out the present method 100, the controller 50 is equipped with application-specific amounts of volatile and non-volatile memory (M) and one or more processor(s) (P), e.g., microprocessors or central processing units, as well as other associated hardware and software, e.g., a digital clock or timer, input / output circuits, buffer circuits, application-specific integrated circuits (ASICs), systems-on-a-chip (SoCs), electronic circuits, and other necessary hardware required to provide the programmed functionality. The controller 50 communicates with the RESS 12 and thus knows its current state of charge (SOC), distances to available EVSE charging stations 16, and, with a corresponding measuring circuit 50L, as shown below with reference to Figures 3-5. With brief reference to Fig. 2, the method 100 and the controller 50 of the present disclosure provide an integrated hardware and control software strategy which, together, enables a user of the host vehicle 10 of Fig. 1 to discharge energy from the RESS 12 when the AC electrical device 14A or 14B is plugged into the AC charging input 20 and successfully identified. In an EV context, the main purpose of the AC charging input 20 is to enable an electrical connection with the EVSE charging station 16 of Fig. 1. For this purpose, the EVSE charging station 16 is typically equipped with an EVSE charging plug similar to the illustrated end plug 18C-1, which in turn is coupled to the EVSE charging station 16 via an electrical cable 21. In the illustrated exemplary J1772 configuration, the EVSE charging plug and the end connector 18C-1 used here terminate a length of cable 21 at a charging handle 30, the charging handle 30 being located at the first distal end E1. As is known in the prior art, such a charging handle 30 comprises an end connector 31 with separate pins for the voltage lines 1 (L1), 2 / neutral (L2 / N), and ground (G) in a typical single-phase configuration. Two additional pins, CP and PRX, are included to carry a control pilot voltage and a proximity voltage, respectively. A locking button or release 32 is located on the top of the plug handle 30, with a responding latch 34 being located adjacent to the end connector 31. When activated by the locking trigger 32, the locking mechanism 34 securely engages the counter-structure of the AC charging input 20, which is located on the host vehicle 10 of Fig.1, thereby ensuring that the end connector 18C-1 remains attached during a charging or discharging process. Recognition based on VCP and VPRX: Within the scope of the present disclosure, the controller 50, schematically depicted in Fig. 1, is configured to execute the instructions embodying the method 100 to cause the processor (P) to automatically recognize a plug connection of the AC electrical device 14A or 14B with the AC charging input 20. Since the EVSE charging station 16 could also be connected during the normal course of initiating a normal EV charging process, the controller 50 uses the resident logic and associated measuring circuit 50L of Figs. 3, 4, and 5 to eliminate the possibility that the connected external device is actually the EVSE charging station 16. Furthermore, the controller 50 automatically distinguishes between the different AC electrical devices 14A and 14B based on a unique modified or modulated corresponding voltage signal, i.e.,the approach and / or control voltages in various embodiments, with possible activation of the locking release 32 of Fig. 2 . In the various embodiments described below, for example, a connection to the EVSE charging station 16 of Fig. 1 would result in voltage signals corresponding to a state-of-charge voltage, which is outside the scope of this disclosure. However, a connection to the V2L load connection box 22 of Fig. 1 results in a different second modulated voltage signal, as disclosed here. Likewise, connecting the higher-voltage AC electrical device 14B in a fast-charging scenario results in a third modulated voltage signal, the first, second, and third modulated voltages being unique to allow the controller 50 to quickly and accurately distinguish between them before enabling current flow to or from the RESS 12. By using the representative circuit topologies of Figs. 3, 4, and 5 according to the method 100 shown in Fig. 6, the controller 50 automatically detects the respective AC electrical device 14A or 14B when it is connected to the AC charging input 20, as mentioned above, and then takes the necessary measures to initiate and control the power output function. The controller 50 automatically detects a desired output voltage from the RESS 12 using the proximity and / or control pilot circuit. The controller 50 can also automatically terminate the described discharge mode before the RESS 12 is depleted, thus enabling the user to reach the nearest EVSE charging station 16 and / or destination.Exemplary circuit topologies for implementing the present teaching, including the detection of specific voltages and / or PWM duty cycles for the purpose of identifying the AC electrical device 14A or 14B, are now described with reference to Fig. 3-5. APPLICATION CASE 1 - VEHICLE-TO-LIVE (V2L) and AC ACCESSORIES: Referring to Fig. 3, the application case described above, in which the host vehicle 10 of Fig. 1 is electrically connected to the AC electrical device 14A, e.g., in the form of one of the AC discharge accessories 15A, 15B, and / or 15C, can be implemented via the V2L load connection box 22, which in turn comprises the V2L load connection box 22 and an associated V2L cable set 18. The RESS 12 is shown schematically to include its various battery cells 12C, a pair of high-voltage contactors 120, and a current-limiting resistor (R0). The RESS 12 is electrically connected to a bidirectional inverter 42.As indicated by the double arrows AC ←→ DC, the bidirectional inverter 42 is configured to convert alternating current to direct current and vice versa as required, depending on whether the bidirectional inverter 42 is used in a charging application or, within the scope of the present disclosure, during discharging. Parts of the host vehicle 10, shown schematically in Fig. 3, include the present control unit 50 and the measuring circuit 50L, the latter being internally connected to the voltage terminals (3), (4) and (5) of the AC charging input 20, wherein voltage terminal (3) corresponds to electrical ground / G, voltage terminal (4) carries the control pilot voltage / CP and voltage terminal (5) carries the proximity voltage / PRX. The remaining two terminals, i.e. voltage terminal (1) L1 and voltage terminal (2) L2 / N, are connected to the bidirectional inverter 42. In the measuring circuit 50L, various resistors R2, R3, R4, and R5 with predetermined ohmic resistance values ​​are arranged as shown, with resistors R2 and R3 connected in parallel. An electrical switch S2 is arranged between the terminals of the parallel resistors R2 and R3, which is open when the specified additional functions are performed. The control voltage terminal (4) is connected to the anode of a control diode D1, the cathode of which is connected to the remaining terminals of resistors R2 and R3. Resistor R5 is connected between the control voltage terminal (5) and electrical ground (G), i.e., the voltage terminal (3) of the AC charging input 20, with resistor R4 connected in series between the control voltage terminal (5) and a regulated (ref) low-voltage source, e.g., +5V. Within the end connector 18C-1 of the V2L cable assembly 18 shown in Fig. 1, a manually controlled switch S3 is connected in parallel to another resistor R7, as shown, with the terminals of switch S3 and resistor R7 connected to the ground terminal (3). As explained below, in one possible configuration, switch S3 can be connected to or integrally constructed with the locking release 32 of Fig. 2 and thus be selectively opened or closed by actuating the locking release 32. In other embodiments, a further optional switch S4 is used, shown in a phantom line in parallel to a resistor R*, arranged externally with respect to the locking release 32, and having an open / closed state independent of a corresponding open / closed state of the locking release 32.When integrated with the interlock release 32, the switch S3 can be pressed and released according to a predetermined sequence to assist in the modulation of a low-voltage signal for the identification of the connected AC electrical device 14A. The opposite terminals of such switch S3 and resistor R7 are connected to one terminal of resistor R6, the opposite terminal of resistor R6 being connected to the PRX voltage terminal (5) carrying the proximity voltage. Thus, when the end plug 18C-1 is inserted into the AC charging input 20, the voltage terminals (1)-(5) of the end plug 18C-1 engage with or connect to the voltage terminals (1)-(5) of the AC charging input 20 to establish the various electrical connections shown in Fig. 3. While the specific resistance levels of resistors R6 and R7 may vary depending on the intended application, the exemplary embodiment shown in Fig. 1 may exhibit representative resistance levels of 150 Ω and 330 Ω, respectively, for a representative multiphase 120 V rated electrical load of 14 A. The V2L load junction box 22 contains several AC outlets 24, e.g., typical three-prong NEMA outlets with integrated fuses F1 and F2, which form AC circuit breakers. Within the V2L load junction box 22, the connections of such outlets 24 correspond to the voltage lines 1, 2, and earth (L1, L2 / N, and G, respectively). To provide a single-phase AC output, the V2L cable set 18 from Fig. 1 terminates in a connection with the described terminal block 18C-2 via the terminal block 25. A residual current device (RCD) 28 can be connected to the lines L1 and L2 / N. To meet the requirements of the RCD, an equipment ground can be established near the terminal block 18C-1 by connecting the high-voltage neutral line (N) to earth (G), e.g., via the terminal block 25. B. via a conductive bridging element 27. As mentioned above, switch S3 can be held / released according to a predetermined sequence to signal the connection of the 14A AC electrical device. More precisely, activation of switch S3 by a user via the toggling of the latching release 32 (Fig. 2) can be used for modulation in a highly generalized sense, providing a unique voltage signal on the proximity voltage line (PRX) to terminal (5). This unique modulated voltage signal can be used by the controller 50 to identify the desired AC output voltage to be supplied to the connected 14A AC electrical device. The controller 50 can therefore read the proximity voltage at terminal (5) to determine the identity of the connected 14A AC electrical device. Alternatively, the optional separate switch S4 can be connected in series between resistor R6 and the voltage terminal (5), i.e., the proximity voltage terminal. Such a switch S4 can be used to toggle or modulate the proximity voltage without having to activate switch S3. Advantages of using such a switch S4 include a clear user confirmation sequence for entering the discharge state, which cannot be confused with a desired locking action, and enabling this strategy to be used in areas where switch S3 is not employed. Referring to Fig. 5, which will be discussed in detail below, a similar end effect can be achieved by connecting another resistor R8 to the CP voltage terminal (4), i.e., the special terminal that carries the control pilot voltage. Using resistor R8 as a sensor, the controller 50 could effectively measure a current flowing through resistor R8 to aid in the identification of the connected AC electrical device 14A, without requiring the user to operate switches S3 or S4 of Fig. 3 in the manner described above. As can be seen, connecting resistor R8 at the indicated circuit location would change the proximity voltage at the voltage terminal (5). Therefore, using resistor R8 at this location would necessitate a corresponding increase in the resistance value of resistor R6 to allow for an accurate measurement.However, the passive detection enabled by resistor R8 would help to eliminate the need for manual switch activation and is therefore useful in some applications. Referring to Fig. 4, in another V2L embodiment, an optional active control circuit 60 with control electronics in the form of an application-specific integrated circuit (ASIC) 62 with an oscillator (OSC) 63 can be integrated into the end connector 18C-2 of the V2L cable set 18 (see Fig. 1). The pilot control circuit 60 can be configured to actively vary or modulate a control pilot frequency, e.g., via pulse width modulation (PWM), with such actions being powered by a low-voltage battery (BAT) 61, e.g., a 5 V battery. The unique modulated frequency and / or voltage could thus indicate which of the AC electrical devices 14A or 14B has been connected.For example, ASIC 62 could use oscillator 63 to output a 500 Hz signal indicating AC electrical device 14A, a 750 Hz signal indicating AC electrical device 14B, and 1 kHz for a typical EVSE charging process where the host vehicle 10 is connected to the EVSE charging station 16. These frequencies are representative and non-limiting; the actual values ​​may differ, provided there is sufficient spacing between the different frequencies. APPLICATION CASE No. 2 - JUMP CHARGE: Referring to Fig. 5, the present teaching can be applied in the above-described application case of jump charging ("Jmp-Chg"), in which a user of the host vehicle 10 shown in Fig. 1 wishes to discharge energy from the RESS 12 of the host vehicle 10 to the RESS 112 of the secondary vehicle 10A. Such a connection can consist of connecting the jump-start charging cable set 19 from Fig. 1 to the EVSE charging cable set 180. That is, the end connector 19C-2 of the jump-start charging cable set 19 is connected to the end connector 180C-2 of the EVSE charging cable set 180, with the opposite end connector 180C-1 in turn being plugged into the AC charging input 200 of the secondary electric vehicle 10A. In the jump-start setup shown in Fig. 5, the power discharge ultimately occurs at a higher voltage than was used in the AC accessory application shown in Figs. 3 and 4. Accordingly, the specially configured jump-start cable set 19 can be used for the jump-start application by having internal resistors R6 and R7 with different values ​​than their counterparts in Figs. 3 and 4. In a typical jump-start charging operation, a user of the host vehicle 10 connects the end connector 19C-1 of the jump-start charging cable set 19 to the AC charging input 20. The opposite end of the jump-start cable set 19 terminates in end connector 19C-2, which is then connected to end connector 180C-2 of the EVSE charging cable set 180. This establishes an electrical connection to the voltage terminals (1), (2), and (3), i.e., L1, L2 / N, and G. At this stage, the mutual communication ports (Com) of the EVSE charging cable set 180 and the jump-start cable set 19 are also connected, with a communication circuit board (PCB) 70 of the latter being connected to the Com port and, as understood in the prior art, being configured to monitor and coordinate the two-way communication between the secondary electric vehicle 10A and the main vehicle 10. The activation of switch S3 for use in the circuit topology shown, or of the optional separate switch S1 of Fig. 4, can be performed manually in such a sequence that a unique / modulated proximity voltage (PRX) is transmitted to the proximity voltage terminal (5). Again, the activation sequence can be predefined to achieve a desired voltage effect, such as a press and hold sustained for a calibrated duration, a rapid double press and release, etc. The proximity voltage is then read by the controller 50 and interpreted as the identity of the connected AC electrical device 15B, as described above. To provide a suitable proximity voltage indicating the step charge event, resistors R6 and R7 can be set to a predetermined level, e.g.,51Ω and 430Ω, or other suitable values, can be set to indicate the desire to initiate a jump charging action. As in Figs. 3 and 4, there are alternatives where the control voltage applied to terminal (4) is modulated to match the connected device, in this case the secondary vehicle 10A of Fig. 1, more precisely the RESS 112 located therein. The various circuit topologies described above with reference to Figs. 3, 4, and 5 can be controlled in accordance with the present method 100. In general terms, possible embodiments of the method 100 operate while the AC charging input 20 of the host vehicle 10 is electrically connected to the external AC electrical device 14A or 14B of Fig. 1.Once this connection is established, the controller 50 automatically detects the control pilot voltage (CP) and the proximity voltage (PRX) present at the respective pilot and proximity voltage terminals of the AC charging input 20. When the control voltage is zero volts (0V), the controller 50 evaluates whether the input conditions are met, e.g., by processing the enable signal (arrow ENBL) of Fig. 1, where such input conditions indicate a request from a user of the host vehicle 10 to supply power from the RESS 12 to the AC electrical device 14A or 14B. In response to the fulfillment of the input conditions, the controller 50 receives the modulated voltage signal described above, where the modulated voltage signal is a predetermined signal variation of the proximity voltage and / or the control pilot voltage in various possible embodiments. The controller 50 then compares the modulated voltage signal with an expected voltage, indicating the identity of the AC electrical device 14A or 14B. Once the device 14A or 14B has been properly identified, the controller 50 discharges the electrical power from the RESS 12 through the intermediate conductors of the cable set 18 or 180 if the modulated voltage signal matches the expected voltage. The configuration of the controller 50 allows it to automatically switch between the AC accessories, e.g., 15A, 15B, or 15C from Fig.1 or other 120V AC accessories, on the one hand, and the jump-start charging cable set 19 and the EVSE charging cable set 180, on the other hand, to distinguish when the modulated voltage signal matches different corresponding expected voltages. Referring to Fig. 6, a non-limiting exemplary embodiment of the method 100 begins at block B102, where the AC electrical device 14A or 14B is connected to the AC charging input 20 of the host vehicle 10 shown in Fig. 1. Since the connection of the AC electrical device 14B corresponds to an application of the jump-start charging connection (“JCC”), logic block B102 is abbreviated as “CONN V2L, JCC” for clarity. As part of logic block B102, the voltage terminals (1)-(5) of the AC charging input 20 receive the corresponding mating pins of either the portable V2L cable set 18 or the jump-start charging cable set 19. The opposite end of the V2L cable set 18 is connected to the V2L load terminal box 22 (Figs. 3 and 4), while in the case of fast charging, the fast charging cable set 19 is connected to the AC charging input 200 via the intermediate EVSE charging cable set 180. The procedure 100 then continues with block B104.In block B104, the controller 50 detects the pilot voltage (VCP). As shown in Figs. 3 and 4, the pilot voltage is present, for example, at the voltage terminal (4) and can be read by the controller 50 using the associated measuring circuit 50L. The procedure 100 continues with block B106 as soon as the pilot voltage has been measured. In block B106, the controller 50 next determines whether the pilot voltage measured in block B104 is 0 V, which is the expected voltage value before power delivery to an unexcited device such as the AC electrical devices 14A and 14B. However, in an EVSE charging scenario, i.e., one in which the host vehicle 10 is connected to the representative offboard EVSE charging station 16 of Fig. 1, the pilot control voltage is a predetermined non-zero value. The procedure 100 proceeds to block B110 if the pilot voltage is not zero, and proceeds to block B108 instead if the pilot voltage is the expected value of 0 V. Block B108 comprises determining the proximity voltage (“DET VPRX”) via the controller 50, e.g., by reading the corresponding voltage at the terminal (5) shown in Fig. 3-5. The method 100 continues with block B112 as soon as the proximity voltage has been determined by the controller 50. Block B110, in response to the detection of a non-zero pilot control voltage in Block B106, includes the execution of normal plug-in charging functions (“EXEC CHG”). Such an operation is performed when the detected non-zero pilot control voltage corresponds to a predetermined charging value, according to the existing region-specific charging protocols, and proceeds according to those protocols. Procedure 100 is complete. In block B112, the control unit 50 next compares the proximity voltage (VPRX) from block B108 with the corresponding values ​​to initiate the current delivery to the AC electrical device 14A or 14B, either via the V2L load connection box 22 or the jump-start cable set 19. As described above, the V2L connection in a typical embodiment is carried at 120 V AC, while the AC voltage in the jump-charge case may be approximately 240 V AC or otherwise differ sufficiently in magnitude from that of the discharge accessory use case. Therefore, the proximity voltage for each use case is uniquely set in the memory (M) of the control unit 50 so that the control unit 50 can quickly distinguish between the two possible connections after first ruling out the possibility that the connection could be the EVSE charging station 16 shown in Fig. 1.Procedure 100 then proceeds to block B114 if the proximity voltage matches one of the corresponding values ​​for the AC electrical device 14A or 14B, alternatively repeating block B104. In block B114 of Fig. 5, the controller 50 next detects input conditions (“DET COND”) indicating a desire to initiate current delivery from the RESS 12 to the connected AC electrical device 14A or 14B. Various approaches are described above, including the detection of a specific activation sequence of the latching release 32 of Fig. 2, corresponding to an open / closed state of the connected switch S3 (Figs. 3-5) or the optional additional switch S1 (Fig. 4), or passive detection when the optional resistor R8 is used. Alternative embodiments, where the detected voltage is the control pilot voltage instead of the proximity voltage, are also possible, for example, via the operation of circuit 60 of Fig. 4. The method 100 then proceeds to block B116. Block B116 involves initiating the discharge mode (“DISCH”). The controller 50 thus regulates the operation of the bidirectional inverter 42 as needed to supply current from the cells 12C of the RESS 12 via the voltage terminals (1) and (2) to the connected AC electrical device 14A or 14B. The procedure 100 then proceeds to block B118. Block B118 includes the automatic monitoring of the current state of charge (SOC) of the RESS 12 during discharge and the comparison of the current SOC with a first calibrated threshold (SOC1), e.g., 60%–70% or another suitable application-specific value, where 100% corresponds to a fully charged set of battery cells 12C and 0% to a fully discharged state, as is generally known in the art. If the current SOC falls below the first calibrated threshold (SOC1), the process 100 proceeds to block B120. If the current SOC remains above the first calibrated threshold, the controller 50 executes blocks B114, B116, and B118 in a loop as long as the current SOC remains above the first calibrated threshold (SOC1) or until the user terminates the discharge process before reaching such a threshold. In block B120, the controller 50 can determine the distance to the nearest available EVSE charging station 16 and / or the next destination. Such locations can be stored in the controller 50's memory as fixed geolocations in a lookup table, which the controller 50 can quickly reference, or the controller 50 can determine the distance in real time via communication with an onboard navigation system, the user's mobile device 11 (Fig. 1), etc. Since a user of the host vehicle 10 typically uses a power outlet in their garage or at their residence to charge the RESS 12, the user's residence can be taken into account when determining the nearest charging station. As part of Block B120, the controller 50 can automatically derive the required state of charge (SOC2) for traveling the distance. Since the distance / location is static due to the discharge mode, and the SOC changes dynamically during discharge, the corresponding SOC2 needed to reach the destination is used. Block B120 can also determine the user's next destination, either by prompting the user before the discharge process begins or automatically based on past driving history, e.g., via the navigation or infotainment systems mentioned above. If, based on the distance mentioned above, the controller 50 determines that the current state of charge exceeds the state of charge (SOC2) required to reach the next destination ("SOC > SOC2"), procedure 100 repeats Block B116. Otherwise, procedure 100 proceeds to Block B122. Block B122 of Fig. 5 includes the automatic deactivation of discharge operations (“DEACT DISCH”) when the defined SOC limit is reached. Since block B122 could be accessed from blocks B120 or B122, the respective triggering limit could be the first limit (SOC1) or the second limit (SOC2). The procedure 100 is complete when the discharge operations have finished. The user then disconnects the electrical load 14A or 14B from the EV charging port 20, after which the host vehicle 10 is ready to resume normal driving operation. Using the method 100 of Fig. 6 and the controller 50 shown in Fig. 1, in conjunction with the various circuit implementations shown in Figs. 3-5, the present teaching offers a number of advantages. For example, to meet the high-voltage insulation requirements, the described strategy allows the discharge of the RESS 12 to the connected AC electrical device 14A or 14B only when the controller 50 detects that the control voltage is initially 0 V, the proximity voltage is within a certain range, and the discharge is enabled by the user of the host vehicle 10. Based on the magnitude of the proximity voltage, the controller 50 is able to automatically detect the voltage level requested by the user for supplying the connected AC electrical device 14A or 14B, in this example 120 V or 240 V, respectively. Furthermore, the present teaching enables the user to activate the discharge mode by using the J1772 connector release switch 32 of Fig. 2, e.g., by a double-click, press and hold, or another predetermined activation sequence, or by a separate switch S1 (Fig. 4) that performs a similar function to change the proximity voltage. Other embodiments allow automatic detection of the connected electrical load 14A or 14B by temporarily using a specific control voltage and / or a PWM duty cycle from the V2L load terminal box 22, which can be supplied by the battery 61 from Fig. 4. The discharge of the RESS 12 is automatically interrupted when a predetermined state of charge (SOC) of the battery cells 12 is reached, the thresholds being optionally set by the user or automatically based on proximity to the nearest charging station 16 and / or the next destination.This approach, in turn, helps to ensure that the RESS 12 is not discharged to an extent that would prevent meaningful propulsion operation of the host vehicle 10. The detailed description and the drawings or figures are supporting and descriptive of the present teaching, but the scope of the present teaching is defined exclusively by the claims. While some of the best modes and other embodiments for carrying out the present teaching have been described in detail, various alternative designs and embodiments for carrying out the present teaching exist, which are defined in the appended claims. Furthermore, this disclosure expressly includes combinations and subcombinations of the elements and features shown above and below.

Claims

A method (100) for detecting an externally connected AC electrical device, (14A, 14B) via a host system (10) with a rechargeable energy storage system, RESS, (12) and an AC charging input (20) connected to the RESS (12), the method (100) comprising: while the AC charging input (20) is electrically connected to the AC electrical device (14A, 14B) via a vehicle-to-live (V2L) load connector and a V2L cable set forming a V2L connection, or via a jump-start charging cable set and an EVSE charging cable set, Electric Vehicle Service Equipment, forming a jump-start charging connection, detecting a control pilot voltage and a proximity voltage at a respective pilot voltage terminal and proximity voltage terminal of the AC charging input (20);When the control pilot voltage is zero volts, evaluate, via the controller (50), whether entry conditions are met, wherein the entry conditions indicate a request by a user of the host system (10) to discharge current from the RESS to the AC electrical device (14A, 14B); receive, via the controller (50), a modulated voltage signal from the V2L connection or from the jump-start charging connection in response to the entry conditions, wherein the modulated voltage signal is a predetermined signal variation of the proximity voltage and / or the control pilot voltage; identify, via the controller (50), the AC electrical device (14A, 14B) as an identified device, including comparing the modulated voltage signal with an expected voltage, which indicates identity of the AC electrical device;and discharging electrical energy from the RESS (12) to the identified device via the V2L connection or the jump-start charging connection when the modulated voltage signal matches the expected voltage, wherein the identified device is a 240 V AC auxiliary device and wherein the discharge of electrical power from the RESS (12) to the identified device occurs via the jump-start charging connection when the modulated voltage signal matches the expected voltage, further comprising: monitoring a current state of charge, SOC, of ​​the RESS (12) via the controller (50);and automatic interruption of the electrical power delivery from the RESS (12) to the identified device when the current SOC is below a SOC threshold, wherein the host system (10) is a host vehicle, the RESS comprises a high-voltage traction battery pack of the host vehicle, and the AC charging input (20) is an EVSE charging input, and wherein the current SOC is a current SOC of the traction battery pack, further comprising: determining, via the controller (50), a distance between the host vehicle (10) and a nearest charging station or destination; and automatically adjusting the SOC threshold based on the distance and the current SOC. The method according to claim 1, wherein the entry conditions comprise a release signal from a mobile device or from an integrated device of the host system (10). The method according to claim 1, further comprising: measuring, via the control (50), the proximity voltage while a user of the host system (10) switches a switch of the V2L cable set or the jump-start charging cable set. The method according to claim 3, wherein the V2L cable set or the jump-start charging cable set comprises a lock (34) and a lock release (32) configured to open and close the lock (34), wherein the switch is connected to the lock release (32), wherein the method (100) further comprises: selectively opening or closing the switch by actuating the lock release (32).

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