VEHICLE START-STOP SYSTEM

Abstract

Vehicle starter assembly (18) comprising: • a circuit (34) configured to operate in a charge state and a discharge state; • a first energy storage device (38) and a second energy storage device (40) electrically connected to the circuit (34), wherein the first energy storage device (38) and the second energy storage device (40) are connected in parallel with each other in the charging state and are connected in series with each other in the discharging state; • a current control circuit (36) electrically connected to the first energy storage device (38); and • a processor (50) programmed to detect an engine request and output a switching control signal that switches the switching circuit (34) between the state of charge and the state of discharge, wherein the processor (50) is programmed to output a current control signal to the current control circuit (36), and wherein the current control circuit (36) is programmed to maintain a constant amount of current flow through the first energy storage device (38) and the second energy storage device (40) in accordance with the current control signal, characterized in that the processor (50) is programmed to output the current control signal, reduce the current flow through the first energy storage device (38) and the second energy storage device (40) to a first predetermined value before outputting the switching control signal to the switching circuit (34).

Description

BACKGROUND

[0001] Automotive start-stop systems reduce fuel consumption and emissions. Start-stop systems shut down an internal combustion engine under certain conditions, such as when a vehicle is temporarily stopped, to reduce the amount of time the engine is idling. The engine is restarted in response to, for example, the driver pressing the accelerator pedal. A starter motor is used to restart the engine.

[0002] The document US 2015 / 0377203 A1 discloses an alternator-starter system with batteries. In a motor mode, in which the batteries are connected in series, an electric machine drives an internal combustion engine, and in a generator mode, in which the batteries are connected in parallel, the electric machine is driven by the internal combustion engine to charge the internal combustion engine. The document DE 102 53 372 A1 shows an engine starting system with batteries that are connected in series with a starter motor to start an internal combustion engine and in parallel with a starter generator for charging. In the document US 2010 / 0244459 A1, a capacitor is used in addition to a battery. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows an example vehicle with an arrangement for charging from a low-voltage power grid and discharging to a starter motor. Fig. 2 is a block diagram of example components of the vehicle assembly of Fig. 1. Fig. 3 is a flowchart of an example process that may be performed by the vehicle assembly. Fig. 4 is a flowchart of another example process that may be performed by the vehicle assembly. Fig. 5 is an electrical diagram of example components of the vehicle assembly of Fig. 1 to illustrate energy storage devices in a parallel design. Fig. 6 is an electrical diagram of example components of the vehicle assembly of Fig. 1, to represent energy storage devices in a series configuration. Fig. 7 is a block diagram of the example components of the vehicle assembly of Fig. 1, to represent electrical switches for connecting the energy storage devices in parallel design to the low-voltage power grid. Fig. 8 is a block diagram of the example components of the vehicle assembly of Fig. 1, to represent electrical switches for connecting the energy storage devices in series with the starter. DETAILED DESCRIPTION

[0003] Continuously stopping and starting an engine while driving on a road presents new challenges for the vehicle's low-voltage (12-volt) electrical system. The starter motor typically draws a significant amount of power when starting the engine. A dedicated starter motor power source, separate from the standard automotive low-voltage system, can help minimize electrical fluctuations in the 12-volt power line. In other words, isolating the starter motor power source from the low-voltage electrical system can prevent, for example, dimmed interior lighting and headlights, a momentary reduction in engine idle, a brief shutdown of 12-volt loads, and so on.

[0004] However, adding another power source, such as a 12V lead-acid battery solely for the starter motor, places additional strain on the vehicle's electrical system, requiring additional cost and effort to control and maintain sufficient battery voltage for repeated restarts. A lead-acid battery is a common choice for starting the engine in low temperatures due to its cold-cranking capability. However, lead-acid batteries are not always compatible with other power sources. For example, a 12V lithium-ion battery has a different voltage profile, which can compromise the lead-acid battery, especially at lower temperatures.

[0005] One way to reduce electrical system costs while still providing sufficient power for the starter motor involves replacing the lead-acid battery with another energy storage device, such as an ultracapacitor. Ultracapacitors tend to have a much longer cycle life, meaning they are capable of a higher number of complete charge and discharge cycles, than a conventional automotive battery. An exemplary electrical start-stop system using an ultracapacitor includes a processor programmed to connect the ultracapacitor to the starter motor upon receiving an engine start request and to disconnect the ultracapacitor from the starter motor upon receiving an engine run command.

[0006] The ultracapacitors can charge from the 12-volt vehicle system voltage and discharge at a higher voltage, for example, higher than 20 volts, by using a circuit that switches rows of ultracapacitors between parallel and series configurations. The higher voltage, in conjunction with current control, can allow the ultracapacitors to operate at a discharge operating current when the engine starts; this can increase the service life of the starter motor. The current control capability can be used to reduce the load on the vehicle's 12-volt energy storage device by limiting the deep discharges otherwise required to recharge the ultracapacitors.A further advantage of current control is the ability to reduce the current to zero before switching between the parallel configuration (charging) and the series configuration (discharging) of the ultracapacitors; thus, sparking at the switch can be excluded.

[0007] The elements shown may take many different forms and may include multiple and / or different components and features. The example components shown are not limiting. In fact, additional or alternative components and / or implementations may be utilized. Furthermore, the elements shown are not necessarily drawn to scale unless expressly stated as such.

[0008] As in Fig. 1, a vehicle starter system 10 of a host vehicle 12 includes a starter motor 14, a low-voltage power grid 16, and a vehicle starter assembly 18. The vehicle starter assembly 18 includes a power source 20 and is capable of maintaining a state of charge, i.e., a percentage of the total energy contained in the power source 20, in the power source 20 sufficient to start an engine 22, for example, an internal combustion engine, of the host vehicle 12. For example, when the vehicle starter assembly 18 detects an engine request in the form of an engine start command, the power source 20 may be electrically disconnected from the low-voltage power grid 16 and connected to the starter motor 14, where the power source 20 is discharged to start the engine 22.Furthermore, when the vehicle starter assembly 18 detects the engine request in the form of an engine run command, the vehicle starter assembly 18 may electrically disconnect the power source 20 from the starter 14 and reconnect it to the low-voltage power grid 16, where the power source 20 may be charged. The vehicle starter assembly 18 may include any number of electrical components that, when combined, can sense an input voltage Vin and an output voltage Vout. The input voltage Vin may be defined as the voltage across the vehicle starter assembly 18 when connected to the low-voltage power grid 16 (see . Fig. 5). The output voltage Vout can be defined as the voltage across the vehicle starter assembly 18 when connected to the starter 14 (see Fig. 6). As discussed below, a current in the energy source 20 may be controlled during charging, discharging, and when the energy source 20 is switched from either the low-voltage power grid 16 or the starter motor 14. Some or all of the components of the vehicle starting system 10, as well as the engine demand, may communicate with each other via a communication link, such as a Controller Area Network (CAN) bus, an Ethernet, or the like.

[0009] The starter 14 may include any number of mechanical and electrical components that, when combined, work together to start the engine 22. For example, the starter 14 may include a starter motor 24, such as a permanent magnet or DC electric motor, that mechanically connects to the engine 22. The starter 14 may include a starter solenoid 26 responsible for electrically connecting the power source 20 to the starter motor 24 so that the starter motor 24 can rotate and potentially start the engine 22. The electrical components may sense a starter voltage, which may be defined as the voltage across the starter 14.

[0010] The low-voltage power system 16 may include any number of mechanical and electrical components that, when combined, maintain a stable operating system voltage for the host vehicle 12. For example, the low-voltage power system 16 may include an alternator 28, a 12-volt power source 30, e.g., a lead-acid battery, a lithium-ion battery, etc., and electrical loads 32, e.g., headlights, radio, cigarette lighter, etc. The alternator 28 may be mechanically connected to the prime mover 22 and electrically connected to the vehicle starter assembly 18. The combination of the alternator 28 and the 12-volt power source 30 may charge the power source 20 of the vehicle starter assembly 18 when the power source 20 is connected to the low-voltage power system 16.The electrical components can detect a low voltage power grid voltage, which is defined as the voltage across the low voltage power grid 16.

[0011] The host vehicle 12 may be any passenger or commercial vehicle, such as a car, a truck, an SUV, a crossover vehicle, a van, a minivan, a taxi, a bus, a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), etc., wherever the power engine 22 is present in the host vehicle 12.

[0012] Now referring to Fig. 2, the vehicle starter assembly 18 includes a power source 20, a switching circuit 34, a current control circuit 36, and a processor 50. Some or all of these components may communicate with each other via a communication link, such as a Controller Area Network (CAN) bus, an Ethernet, or the like.

[0013] The energy source 20 may include a first energy storage device 38 and a second energy storage device 40. The first energy storage device 38 and the second energy storage device 40 may be electrically connected to the circuit 34. The first energy storage device 38 and the second energy storage device 40 may be configured between a parallel configuration (see Fig. 5 and Fig. 7) and a series design (see Fig. 6 and Fig. 8). In the parallel configuration, the first energy storage device 38 and the second energy storage device 40 are connected to the low-voltage power grid 16. In the series configuration, the first energy storage device 38 and the second energy storage device 40 are connected to the starter 14.

[0014] The first energy storage device 38 and the second energy storage device 40 may include any suitable energy storage device capable of being charged rapidly, for example, fully charged within seconds, and capable of being discharged at high currents, for example, at currents of at least one hundred amperes. The first energy storage device 38, the second energy storage device 40, or both, may include, for example, an ultracapacitor. The ultracapacitor design of the first energy storage device 38 and / or the second energy storage device 40 may be a stacked series of ultracapacitors to achieve a higher voltage value. The stacked series of ultracapacitors may be connected in parallel with a corresponding stacked series of ultracapacitors to obtain a higher equivalent capacitance.The stacked series of ultracapacitors can use a voltage compensation circuit (not shown) to keep the individual ultracapacitor voltages balanced. That is, the voltage compensation circuit can monitor each ultracapacitor and adjust the voltage of an individual ultracapacitor to control its voltage within a predetermined voltage range, for example, 50 mV, of the other ultracapacitors in the stacked series.

[0015] The circuit 34 may include any suitable number of electrical switches 42 that interconnect the first energy storage device 38, the second energy storage device 40, the current control circuit 36, an input terminal 44, and an output terminal 46. The circuit 34 has a state of charge as defined by the first energy storage device 38 and the second energy storage device 40 being connected in parallel by the electrical switches 42. In the state of charge, the electrical switches 42 also connect the first energy storage device 38 and the second energy storage device 40 to the input terminal 44 and the current control circuit 36 (see Fig. 7).

[0016] The circuit 34 has a discharge state as defined by the first energy storage device 38 and the second energy storage device 40, which are connected in series by the electrical switches 42. In the discharge state, the electrical switches 42 connect the first energy storage device 38 to the current control circuit 36, and the second energy storage device 40 to the output terminal 46 (see Fig. 8). The circuit 34 may include electrical components that interface with the processor 50 to switch the electrical switches 42 between the charge state and the discharge state through a switch control signal.

[0017] The electrical switches 42 may include any number of electrical components that can be used to switch the first energy storage device 38 and the second energy storage device 40 between the charge state and the discharge state. The electrical switches 42 may include relays, for example, single-pole double-throw (SPDT) switches, triple-pole triple-throw (TPTT) switches, etc. Alternatively, the electrical switches 42 may include solid-state relays, for example, metal-oxide-semiconductor field-effect transistors (MOSFETs), insulated-gate bipolar transistors (IGBTs), etc.

[0018] The vehicle starter assembly 18 may include the input terminal 44, which may electrically connect the vehicle starter assembly 18 to the low-voltage power system 16 (see Fig. 7-8). The input terminal 44 may consist of, for example, a pole terminal, terminal block, plug-in terminal, flat-pin connection, a ring terminal, etc. The input terminal 44 may be a plug or a socket connection.

[0019] The vehicle starter assembly 18 may include the output terminal 46, which may electrically connect the vehicle starter assembly 18 to the starter 14 (see Fig. 7-8). The output terminal 46 may consist of, for example, a pole terminal, terminal block, plug-in terminal, flat-pin connection, a ring terminal, etc. The output terminal 46 may be a plug or a socket connection.

[0020] The vehicle starter assembly 18 may include a common terminal 48 that may electrically connect the vehicle starter assembly 18 to both the low voltage power system 16 and the starter 14 (see Fig. 7-8). The common terminal 48 may be a return line for the input current and the output current of the vehicle starter assembly 18. The common terminal 48 may consist of, for example, a pole terminal, terminal block, push-in terminal, spade connection, ring terminal, etc. The common terminal 48 may be a plug or socket connection.

[0021] Current control circuitry 36 may include any number of electrical components that interface with processor 50 to sense current flow through power source 20, such as a Hall-effect sensor, a low-resistance sense resistor, etc. As discussed above, current control circuitry 36 may include any number of electrical components that may be configured to control current flow, such as constant current, variable current, or zero current, through power source 20 using a current control signal, whether circuitry 34 is in the charging state or the discharging state. The electrical components configured to control current through power source 20 may be, for example, metal-oxide-semiconductor field-effect transistors (MOSFETs), insulated-gate bipolar transistors (IGBTs), etc.The current control circuit 36 may be connected between the first energy storage device 38 and the common terminal 48 (see . Fig. 7-8). The current control circuit 36 may include electrical components that interface with the processor 50 to sense a current control circuit voltage across the current control circuit 36, that is, a voltage from a node between the first energy storage device 38 and the current control circuit 36 to the common terminal 48.

[0022] The processor 50 may include any number of electrical components programmed to detect an engine request in the form of an engine start command. The engine start command may be initiated from any number of sources, for example, an ignition switch, a brake pedal sensor, a key fob unlock command, a driver door open switch, etc. The processor 50 may be programmed to detect any number of electrical quantities, such as the magnitude of current flowing through the power source 20, the power control circuit voltage, the low-voltage power line voltage, and / or the input voltage Vin of the vehicle starter assembly 18, and calculate the state of charge in the power source 20 while the circuit 34 is in the state of charge.The processor 50 may be programmed to determine whether there is sufficient energy in the energy source 20 to start the prime mover 22. In some cases, the processor 50 may be programmed to output the current control signal to maintain the flow of current through the energy source 20 to charge the energy source 20. In some cases, the processor 50 may be programmed to determine whether an upper charge level has been reached, indicating that the energy source 20 is sufficiently charged, and output the current control signal to terminate charging, that is, to reduce the flow of current to the energy source 20 to zero or near zero. In other cases, the processor 50 may be programmed to reduce the flow of current through the energy source 20 to a first predetermined value before outputting the switching control signal to the switching circuit 34.The first predetermined value may be a current low enough to significantly reduce or eliminate switch stresses, such as sparking, etc., as seen in electrical switches 42. Processor 50 may be programmed to output the current control signal in accordance with maintaining a constant current flow while circuit 34 is in the charging state.

[0023] The processor 50 may include any number of electrical components programmed to detect the engine request in the form of an engine work command. The engine work command may be initiated from any number of sources, for example, an ignition switch, a powertrain control module, etc. The processor 50 may be programmed to detect any number of electrical quantities, such as the magnitude of current flow through the power source 20, the current control circuit voltage, the starter voltage, and / or the output voltage Vout of the vehicle starter assembly 18, and to determine the state of charge in the power source 20 while the circuit 34 is in the discharge state.In some cases, processor 50 may be programmed to determine whether a low state of charge has been reached, indicating that power source 20 is sufficiently depleted, and issue the current control signal to terminate the discharge, i.e., reduce the current flow through power source 20 to zero or near zero. In other cases, processor 50 may be programmed to reduce the current flow through power source 20 to a first predetermined value before issuing the switching control signal to switching circuit 34. The first predetermined value may be a current low enough to significantly reduce or eliminate switch stresses, e.g., sparking, etc., as seen with electrical switches 42.The processor 50 may be programmed to output the current control signal in accordance with maintaining a constant current flow while the circuit 34 is in the discharge state.

[0024] Fig. 3 is a flowchart of an example process 300 that may be executed by the vehicle starter system 10 to configure the vehicle starter assembly 18 to transition from the charging state to the discharging state. The process 300 may be executed at any time, such as when the vehicle starter assembly 18 receives the engine start command to start the engine 22 of the host vehicle 12. In some possible approaches, the process 300 may be executed after the host vehicle 12 has been parked overnight, and the engine start command is initiated, for example, by the key fob, the door entry switch, or the ignition switch. In another possible approach, the process 300 may be executed after a driver releases the brake pedal, for example, while the host vehicle 12 is stopped at a traffic light.

[0025] At block 302, the vehicle starter assembly 18 may receive the engine start command. The engine start command may be initiated from various sources, as listed above, and received by the processor 50, for example, through the communication link.

[0026] At decision block 304, the vehicle starter assembly 18 may determine whether the power source 20 has sufficient state of charge to start the engine 22. For example, the processor 50 may receive the magnitude of the current flowing through the power source 20, the power control circuit voltage, the low-voltage power grid voltage, and / or the input voltage Vin of the vehicle starter assembly 18 and determine the state of charge of the power source 20. If the state of charge is sufficient to start the engine 22, the process 300 may proceed to block 308. Without sufficient state of charge, the process 300 may proceed to process 306 so that the power source 20 can charge.

[0027] At block 306, the vehicle starter assembly 18 may either begin or continue charging the power source 20. The processor 50 may determine a maximum charging current and output the associated current control signal to the current control circuit 36 to apply the maximum charging current to the power source 20. The maximum charging current may be a constant charging current value. The processor 50 may monitor the current flow by receiving the magnitude of the current flow from the current control circuit 36.

[0028] At block 308, the vehicle starter assembly 18 may prepare to switch the circuit 34 to the discharge state. The processor 50 may reduce the current flow through the energy source 20 to the first predetermined value by outputting the associated current control signal to the current control circuit 36. The processor 50 may monitor the current flow by receiving the magnitude of the current flow from the current control circuit 36.

[0029] At block 310, the vehicle starter assembly 18 may switch the circuit 34 from the charging state to the discharging state. Switching the circuit 34 may include the processor 50 issuing the appropriate switching control signal to switch the circuit 34 from the charging state to the discharging state. The electrical switches 42 are activated, and the first energy storage device 38 and the second energy storage device 40 transition from the parallel configuration, where they were connected to the low-voltage power grid 16, to the series configuration, where they are connected to the starter motor 14.

[0030] At block 312, the vehicle starter assembly 18 is in the discharge state, and the power source 20 is discharging to the starter 14 in an effort to start the engine 22. The processor 50 may determine a maximum discharge current and output the associated current control signal to the current control circuit 36 to apply the maximum discharge current to the starter 14. The maximum discharge current may be a constant discharge current value. The processor 50 may monitor the current flow by receiving the magnitude of the current flow from the current control circuit 36.

[0031] The process 300 may continue to execute block 312 and may continue to discharge the power source 20 to the starter motor 14 until, for example, the processor 50 determines that either the lower state of charge of the power source 20 has been reached or that the engine 22 is commanded to shut down, for example, by the ignition switch, the powertrain control module, etc. In this case, the processor 50 may reduce the current flow through the power source 20 to zero or near zero by outputting the associated current control signal to the current control circuit 36. The processor 50 may monitor the current flow by receiving the magnitude of the current flow from the current control circuit 36.

[0032] Fig. 4 illustrates a flowchart of an example process 400 that may be performed by the vehicle starter system 10 to configure the vehicle starter assembly 18 to transition from the discharge state to the charge state. The process 400 may be performed at any time, such as when the vehicle starter assembly 18 receives the engine run command to disconnect the power source 20 from the starter 14. In some possible approaches, the process 400 may be performed after the engine 22 has successfully started and the engine run command has been initiated, for example, by the ignition switch, the powertrain control module, etc.

[0033] At block 402, the vehicle starter assembly 18 may receive the engine work command. The engine work command may be initiated from various sources, as listed above, and received by the processor 50, for example, through the communication link.

[0034] At block 404, the vehicle starter assembly 18 may prepare to switch the circuit 34 to the charging state. The processor 50 may reduce the current flow through the energy source 20 to the first predetermined value by outputting the associated current control signal to the current control circuit 36. The processor 50 may monitor the current flow by receiving the magnitude of the current flow from the current control circuit 36.

[0035] At block 406, the vehicle starter assembly 18 may switch the circuit 34 from the discharge state to the charge state. Switching the circuit 34 may include the processor 50 issuing the appropriate switching control signal to switch the circuit 34 from the discharge state to the charge state. The electrical switches 42 are activated, and the first energy storage device 38 and the second energy storage device 40 transition from the series configuration, where they were connected to the starter 14, to the parallel configuration, where they are connected to the low-voltage power grid 16.

[0036] At block 408, the vehicle starter assembly 18 is in the charging state, and the power source 20 is being charged by the low-voltage power grid 16. The processor 50 may determine a maximum charging current and output the associated current control signal to the current control circuit 36 to enable the maximum charging current to be applied to the power source 20. The maximum charging current may be a constant charging current value. The processor 50 may monitor the current flow by receiving the magnitude of the current flow from the current control circuit 36.

[0037] The process 400 may continue to execute block 408 and may continue to apply the charging current until, for example, the processor 50 determines that either the upper state of charge of the power source 20 has been reached or that the engine 22 is commanded to turn off, for example, by the ignition switch, etc. In this case, the processor 50 may reduce the current flow through the power source 20 to zero or near zero by outputting the associated current control signal to the current control circuit 36. The processor 50 may monitor the current flow by receiving the magnitude of the current flow from the current control circuit 36.

[0038] Now referring to Fig. 5, the vehicle starter assembly 18 is schematically illustrated in the charging state, where the first energy storage device 38 and the second energy storage device 40 are in parallel configuration. The first energy storage device 38 and the second energy storage device 40 are separated from the starter 14 and connected to the low-voltage power grid 16 and the power control circuit 36.

[0039] Now referring to Fig. 6, the vehicle starter assembly 18 is schematically illustrated in the discharge state, where the first energy storage device 38 and the second energy storage device 40 are in series configuration. The first energy storage device 38 and the second energy storage device 40 are disconnected from the low-voltage power grid 16. The first energy storage device 38 is connected to the power control circuit 36, and the second energy storage device 40 is connected to the starter 14.

[0040] The Fig. 7 and Fig. 8 show the positions of the electrical switches of the circuit 34 for both the parallel layout and the series layout. As in Fig. 7, the electrical switches 42, for example, the three-pole triple circuit (TPTT), in the parallel configuration, connect the first energy storage device 38 and the second energy storage device 40. The electrical switches 42 also connect the first energy storage device 38 and the second energy storage device 40 to the low-voltage power grid 16 and the power control circuit 36. As shown in Fig. 8, the electrical switches 42, for example, the three-pole triple circuit (TPTT), in the series configuration, connect the first energy storage device 38 and the second energy storage device 40. The electrical switches 42 also connect the first energy storage device 38 to the current control circuit 36, and the second energy storage device 40 to the starter 14. The Fig. 7 and Fig. 8 also illustrate the input terminal 44, the output terminal 46 and the common terminal 48 of the vehicle starter assembly 18.

[0041] In general, the described data processing systems and / or devices may employ any of a variety of computer operating systems, including, but not limited to, versions and / or variants of the Ford Sync® application, the AppLink / Smart Device Link middleware, the Microsoft Automotive® operating system, the Microsoft Windows® operating system, the Unix operating system (e.g., the Solaris® operating system distributed by Oracle Corporation in Redwood Shores, California, USA), the AIX UNIX operating system distributed by International Business Machines in Armonk, New York, USA, the Linux operating system, the Mac OSX and iOS operating systems distributed by Apple Inc. in Cupertino, California, USA, the BlackBerry OS distributed by Blackberry, Ltd. in Waterloo, Canada, and the Android operating system distributed by Google, Inc.and the Open Handset Alliance, or the QNX® CAR platform for infotainment offered by QNX Software Systems. Examples of computing devices include, but are not limited to, an in-vehicle computer, a computer workstation, a server, a desktop, laptop, or handheld computer, or other computing system and / or device.

[0042] Data processing devices generally include computer-executable instructions, where the instructions may be executable by one or more data processing devices such as those listed above. Computer-executable instructions may be compiled or interpreted by computer programs created using a variety of programming languages and / or technologies, including, but not limited to, Java™, C, C++, Visual Basic, Java Script, Perl, etc. Some of these applications may be compiled and executed on a virtual machine, such as the Java virtual machine, the Dalvik virtual machine, or similar. Generally, a processor (e.g., a microprocessor) receives instructions from, for example, memory, a computer-readable medium, etc., and executes those instructions, performing one or more processes, including one or more of the processes described herein. Such instructions and other data may be stored and transmitted using a variety of computer-readable media.

[0043] A computer-readable medium (also referred to as a processor-readable medium) includes any non-transitory (e.g., tangible) medium that participates in providing data (e.g., instructions) that can be read by a computer (e.g., by a processor of a computer). Such a medium may take many forms, including, but not limited to, non-volatile media and volatile media. Non-volatile media may include, for example, optical or magnetic disks and other persistent storage. Volatile media may include, for example, dynamic random access memory (DRAM), which is typically main memory. Such instructions may be transmitted using one or more transmission media, including coaxial cables, copper wires, and fiber optics, including the wires comprising a system bus coupled to a processor of a computer.Conventional forms of computer-readable media include, for example, a floppy disk, a floppy disk, a hard disk, magnetic tape, any other magnetic medium, a CD-ROM, a DVD, any other optical medium, punched cards, punched tape, any other physical medium with hole patterns, a RAM, a PROM, an EPROM, a flash EEPROM, any other memory chip or memory card, or any other medium that a computer can read.

[0044] Databases, data repositories, or other data stores described herein may include various types of mechanisms for storing, retrieving, and accessing various types of data, including a hierarchical database, a set of files in a file system, an application database in a proprietary format, a relational database management system (RDBMS), and so on. Each such data store is generally embodied in a computing device employing a computer operating system, such as one of those mentioned above, and is accessed via a network using any one or more of a variety of methods. A file system may be accessible by a computer operating system and may include files stored in various formats.An RDBMS generally uses the Structured Query Language (SQL), in addition to a language for creating, storing, manipulating, and executing stored procedures, such as the PL / SQL language mentioned above.

[0045] In some examples, system elements may be implemented as computer-readable instructions (e.g., software) on one or more computing devices (e.g., servers, PCs, etc.) stored on computer-readable media associated therewith (e.g., disks, memories, etc.). A computer program product may include such instructions stored on a computer-readable medium for performing the functions described herein.

[0046] With regard to the processes, systems, methods, heuristics, etc. described herein, it is understood that although the steps of such processes, etc., have been described as occurring in a particular ordered sequence, such processes could be performed with the described steps in an order different from the order described herein. Furthermore, it is understood that certain steps may be performed concurrently, additional steps may be added, or certain steps described herein may be omitted. In other words, the process descriptions herein are for the purpose of illustrating particular embodiments and should not be construed as limiting the claims in any way.

[0047] Accordingly, it is to be understood that the above description is intended to be illustrative and not restrictive. Many embodiments and applications other than the examples given would become apparent upon reading the above description. The scope of protection should not be determined with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to those claims. It is anticipated and intended that future developments will occur in the technologies discussed herein and that the disclosed systems and methods will be incorporated into such future embodiments. Taken together, it should be understood that the application is susceptible to modifications and variations.

[0048] All terms used in the claims are intended to have their ordinary meaning as understood by persons having extensive knowledge of the technologies described herein, unless explicitly stated otherwise. In particular, the use of singular articles, such as "a," "an," "the," "the," "the," etc., is intended to mean any one or more of the recited elements, unless a claim explicitly states a contrary limitation.

[0049] The Abstract is provided to enable the reader to quickly ascertain the nature of the technical disclosure. It is provided with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Additionally, the foregoing Detailed Description indicates that various features are grouped together in various embodiments for the purpose of more efficient disclosure. This method of disclosure should not be construed as reflecting an intent that the claimed embodiments require more features than are expressly recited in each claim. Rather, as the following claims indicate, the inventive subject matter includes fewer than all of the features of a single disclosed embodiment.Thus, the following claims are hereby incorporated into the detailed description, with each claim standing on its own as a separate claim.

Claims

[1] Vehicle starter assembly (18) comprising: • a circuit (34) configured to operate in a charge state and a discharge state; • a first energy storage device (38) and a second energy storage device (40) electrically connected to the circuit (34), wherein the first energy storage device (38) and the second energy storage device (40) are connected in parallel with each other in the charging state and are connected in series with each other in the discharging state; • a current control circuit (36) electrically connected to the first energy storage device (38); and • a processor (50) programmed to detect an engine request and output a switching control signal that switches the circuit (34) between the charge state and the discharge state, wherein the processor (50) is programmed to output a current control signal to the current control circuit (36) and wherein the current control circuit (36) is programmed to maintain a constant magnitude of current flow through the first energy storage device (38) and the second energy storage device (40) in accordance with the current control signal, characterized by that the processor (50) is programmed to output the current control signal to reduce the current flow through the first energy storage device (38) and the second energy storage device (40) to a first predetermined value before outputting the switching control signal to the switching circuit (34). [2] The vehicle starter assembly (18) of claim 1, further comprising an input terminal (44) electrically connected to the first energy storage device (38) and the second energy storage device (40) via the switching circuit (34) in the charging state. [3] The vehicle starter assembly (18) of claim 2, further comprising an output terminal (46) electrically connected to the second energy storage device (40) via the switching circuit (34) in the discharge state. [4] Vehicle starter assembly (18) comprising: • a circuit (34) configured to operate in a charge state and a discharge state; • a first energy storage device (38) and a second energy storage device (40) electrically connected to the circuit (34), wherein the first energy storage device (38) and the second energy storage device (40) are connected in parallel with each other in the charging state and are connected in series with each other in the discharging state; • a current control circuit (36) electrically connected to the first energy storage device (38); and • a processor (50) programmed to detect an engine request and output a switching control signal that switches the circuit (34) between the charge state and the discharge state, wherein the processor (50) is programmed to output a current control signal to the current control circuit (36) and wherein the current control circuit (36) is programmed to maintain a constant magnitude of current flow through the first energy storage device (38) and the second energy storage device (40) in accordance with the current control signal, wherein the current control circuit (36) is configured to control a current flow through the first energy storage device (38) and the second energy storage device (40) when the circuit (34) is in the charging state and in accordance with the current control signal, characterized by , that the current control circuit (36) is configured to control the current flow through the first energy storage device (38) and the second energy storage device (40) when the circuit (34) is in the discharge state and in accordance with the current control signal. [5] The vehicle starter assembly of claim 4, wherein the processor is programmed to detect a magnitude of current flow and output the current control signal based at least in part on the magnitude of current flow and the circuit (34) operating in the charging or discharging state. [6] The vehicle starter assembly (18) of claim 1, wherein the first energy storage device (38) and / or the second energy storage device (40) include an ultracapacitor. [7] The vehicle starter assembly (18) of claim 1, wherein the energy request includes an engine start command and an engine run command. [8] Vehicle starter system (10) comprising: • a low-voltage electricity network (16); • a starter (14); • a circuit (34) configured to operate in a charge state and a discharge state; • a first energy storage device (38) and a second energy storage device (40) electrically connected to the circuit (34), wherein the first energy storage device (38) and the second energy storage device (40) are connected in parallel with each other in the charging state and are connected in series with each other in the discharging state; • an input terminal (44) electrically connected to the low-voltage power grid (16), the input terminal (44) electrically connecting the first energy storage device (38) and the second energy storage device (40) to the low-voltage power grid (16) when the circuit (34) is in the charging state; • an output terminal (46) electrically connected to the starter (14), the output terminal (46) electrically connecting the second energy storage device (40) to the starter (14) when the circuit (34) is in the discharge state; • a current control circuit (36) electrically connected to the first energy storage device (38); and • a processor (50) programmed to detect an engine request and output a switching control signal that switches the circuit (34) between the charging state and the discharging state, and wherein the processor (50) is programmed to output a current control signal to the current control circuit (36), and wherein the current control circuit (36) is configured to maintain a constant magnitude of current flow through the first energy storage device (38) and the second energy storage device (40) when the circuit (34) is in the charging state in accordance with the current control signal, characterized by , that the first energy storage device (38) and the second energy storage device (40) are separated from the low-voltage power grid (16) in the discharge state. [9] The vehicle starter system (10) of claim 8, wherein the current control circuit (36) is configured to control the flow of current through the first energy storage device (38) and the second energy storage device (40) when the circuit (34) is in the discharge state and in accordance with the current control signal. [10] The vehicle starter system (10) of claim 9, wherein the processor (50) is programmed to detect a magnitude of current flow and output the current control signal based at least in part on the magnitude of current flow and the circuit (34) operating in the charging or discharging state. [11] The vehicle starter system (10) of claim 8, wherein the processor (50) is programmed to output the current control signal to maintain the constant magnitude of current flow through the first energy storage device (38) and the second energy storage device (40). [12] The vehicle starter system (10) of claim 8, wherein the processor (50) is programmed to output the current control signal to reduce the current flow through the first energy storage device (38) and the second energy storage device (40) to a first predetermined value prior to outputting the switching control signal to the switching circuit (34). [13] The vehicle starter system (10) of claim 8, wherein the first energy storage device (38) and / or the second energy storage device (40) includes an ultracapacitor. [14] The vehicle starter system (10) of claim 8, wherein the energy request includes an engine start command and an engine run command.

Images