Power control system for dc-dc converter and inverter pre-charge and shutdown

Abstract

A power control system for DC-DC converter and inverter pre-charge and shutdown is disclosed. The power control system for a propulsion system of a vehicle includes an energy storage system including a pre-charge circuit and one or more battery packs. A DC-DC converter is connected to the energy storage system and includes a first capacitor, a first plurality of power switches, and an inductor. A power inverter module is connected to the DC-DC converter and includes a second capacitor and a second plurality of power switches. A controller is configured to pre-charge the first capacitor of the DC-DC converter and the second capacitor of the power inverter module and control an operating mode of the DC-DC converter and the power inverter module.

Description

Technical Field

[0001] The information provided in this section is for the purpose of presenting the overall context of this disclosure. To the extent described in this section, the work of the currently attributed inventors and aspects of this description that are not otherwise considered prior art at the time of filing are neither expressly nor implicitly regarded as prior art to this disclosure.

[0002] This disclosure relates to battery systems, and more particularly to a power control system for a battery system used in a battery electric vehicle (BEV), the power control system including a DC-DC converter. Background Technology

[0003] A battery electric vehicle (BEV) comprises one or more battery packs, each containing one or more battery cells. The battery system controls the charging and discharging of the batteries. During operation, one or more electric motors of the BEV are used to provide propulsion for the vehicle. The electricity stored in the battery packs is depleted after use, and the BEV is recharged. Options for recharging the battery packs include plugging the device into a public power source at a charging station (such as a commercial or home charging station). Other options may include using electricity stored in another BEV to charge one BEV.

[0004] As is understood, when a vehicle is not at the owner's home, the battery pack of a BEV may be depleted. Currently, depending on various factors, the amount of time required to fully recharge (multiple) battery packs is typically approximately 4-12 hours for a full charge. This charging cycle is significantly longer than the amount of time required to fill the fuel tank of a vehicle that includes an internal combustion engine (less than 10 minutes).

[0005] Some battery electric vehicles (BEVs) have adopted higher voltage battery systems to allow for faster charging of (multiple) battery packs, thus reducing charging time. For example, some fast-charging systems can charge a battery pack to 80% capacity in less than an hour. Operating at higher voltage levels requires additional precautions to reduce potential damage to power control system components during startup and shutdown. Summary of the Invention

[0006] A power control system for a vehicle propulsion system includes an energy storage system comprising a pre-charge circuit and one or more battery packs. A DC-DC converter is connected to the energy storage system and includes a first capacitor, a first plurality of power switches, and an inductor. A power inverter module is connected to the DC-DC converter and includes a second capacitor and a second plurality of power switches. A controller is configured to: pre-charge the first capacitor of the DC-DC converter and the second capacitor of the power inverter module; and control the operating modes of the DC-DC converter and the power inverter module.

[0007] Among other features, the controller is configured to: after pre-charging the first capacitor of the DC-DC converter, control the output voltage of the DC-DC converter to ramp up the voltage across the second capacitor of the power inverter module, thereby pre-charging the second capacitor.

[0008] Among other features, the controller is configured to: after pre-charging the first capacitor of the DC-DC converter, switch the DC-DC converter from standby mode to operating mode and control the output voltage of the DC-DC converter to ramp up the voltage across the second capacitor of the power inverter module, thereby pre-charging the second capacitor. When the difference between the input voltage of the power inverter module and a predetermined target voltage is less than a predetermined threshold, the controller switches the power inverter module from stop mode to operating mode and the propulsion system from stop mode to active mode. When the propulsion system is stopped, the controller is configured to ramp down the output voltage of the DC-DC converter to a voltage less than a first predetermined threshold.

[0009] Among other features, when the output voltage of the DC-DC converter is less than a first predetermined threshold, the controller switches the power inverter module from operating mode to stop mode and the DC-DC converter from operating mode to standby mode. The controller is configured to disconnect the energy storage system and switch the propulsion system from operating mode to stop mode when the input voltage of the DC-DC converter is less than a second predetermined threshold.

[0010] Among other features, a bidirectional bypass switch is connected between the power inverter module and the energy storage system. The controller is configured to close the bidirectional bypass switch and simultaneously precharge the first and second capacitors.

[0011] Among other features, in response to the difference between the voltage across the pre-charge resistor in the energy storage system and the voltage of the first capacitor being less than a first predetermined threshold, the controller selectively switches the energy storage system to normal mode and disconnects the bidirectional bypass switch. The controller determines the difference between the output voltage of the DC-DC converter and the input voltage of the power inverter module. When this difference is greater than a predetermined threshold, the controller incrementally adjusts the output voltage of the DC-DC converter by a delta voltage. When this difference is less than the predetermined threshold, the controller switches the power inverter module from stop mode to run mode and the propulsion system from shut-off mode to active mode.

[0012] Among other features, when the propulsion system is in operating mode, the bidirectional bypass switch is closed and the DC-DC converter is in standby mode, and the controller is configured to stop the propulsion system by: disconnecting the energy storage system; and when the output voltage of the DC-DC converter and the power inverter module is less than a first predetermined threshold, causing the power inverter module to switch from operating mode to stop mode.

[0013] Among other features, when the voltage across the first and second capacitors is less than a second predetermined threshold, the controller causes the propulsion system to switch from an operating mode to a shut-off mode.

[0014] A power control system for a vehicle propulsion system includes an energy storage system comprising a pre-charge circuit and one or more battery packs. A DC-DC converter is connected to the energy storage system and includes a first capacitor, a first plurality of power switches, and an inductor. A power inverter module is connected to the DC-DC converter and includes a second capacitor and a second plurality of power switches. The controller is configured to: pre-charge the first capacitor of the DC-DC converter; transition the DC-DC converter from a standby mode to an operating mode; and determine the difference between the output voltage of the DC-DC converter and the input voltage of the power inverter module. When the difference is greater than a first predetermined threshold, the output voltage of the DC-DC converter is ramped up. When the difference is less than the first predetermined threshold, the power inverter module is transitioned from a stop mode to an operating mode, and the propulsion system is transitioned from a shut-off mode to an operating mode.

[0015] Among other features, when the propulsion system is stopped, the controller is configured to: selectively sag the output voltage of the DC-DC converter; when the output voltage of the DC-DC converter is less than a second predetermined threshold, switch the power inverter module from operating mode to stop mode and switch the DC-DC converter from operating mode to standby mode; disconnect the energy storage system; and when the input voltage of the DC-DC converter is less than a third predetermined threshold, switch the propulsion system from operating mode to stop mode.

[0016] A power control system for a vehicle propulsion system includes an energy storage system comprising a pre-charge circuit and one or more battery packs. A DC-DC converter is connected to the energy storage system and includes a first capacitor, a first plurality of power switches, an inductor, and a bidirectional bypass switch. A power inverter module is connected to the DC-DC converter and includes a second capacitor and a second plurality of power switches; the bidirectional bypass switch is connected between the power inverter module and the energy storage system. A controller is configured to: close the bidirectional bypass switch and simultaneously pre-charge the first and second capacitors; and after pre-charging the first and second capacitors, switch the mode of the DC-DC converter from a standby mode to an operating mode.

[0017] Among other features, the controller is configured to calculate the difference between the output voltage of the DC-DC converter and the input voltage of the power inverter module. When this difference exceeds a predetermined threshold, the controller is configured to incrementally adjust the output voltage of the DC-DC converter by an incremental voltage. When the difference is less than the predetermined threshold, the controller is configured to switch the power inverter module from a stop mode to an operating mode and the propulsion system from a shut-off mode to an active mode.

[0018] Among other features, when the propulsion system is in operating mode, the bidirectional bypass switch is closed and the DC-DC converter is in standby mode. The controller is configured to stop the propulsion system by: disconnecting the energy storage system; and when the output voltage of the DC-DC converter and the input voltage of the power inverter module are less than a first predetermined threshold, switching the power inverter module from operating mode to stop mode. When the voltage of the first capacitor and the second capacitor are less than a second predetermined threshold, the controller switches the propulsion system from operating mode to shutdown mode.

[0019] This disclosure also discloses the following technical solutions:

[0020] Option 1. A power control system for a vehicle propulsion system, the power control system comprising:

[0021] An energy storage system, which includes a pre-charging circuit and one or more battery packs;

[0022] A DC-DC converter connected to the energy storage system and including a first capacitor, a first plurality of power switches and an inductor;

[0023] A power inverter module, connected to the DC-DC converter and including a second capacitor and a second plurality of power switches; and

[0024] The controller is constructed as follows:

[0025] Pre-charge the first capacitor of the DC-DC converter and the second capacitor of the power inverter module; and

[0026] Control the operating mode of the DC-DC converter and the power inverter module.

[0027] Option 2. The power control system according to Option 1, wherein the controller is configured to: after pre-charging the first capacitor of the DC-DC converter, control the output voltage of the DC-DC converter to ramp up the voltage across the second capacitor of the power inverter module, thereby pre-charging the second capacitor.

[0028] Option 3. The power control system according to Option 1, wherein the controller is configured to: after pre-charging the first capacitor of the DC-DC converter, switch the DC-DC converter from standby mode to operating mode and control the output voltage of the DC-DC converter to ramp up the voltage across the second capacitor of the power inverter module, thereby pre-charging the second capacitor.

[0029] Option 4. According to the power control system described in Option 1, when the difference between the input voltage of the power inverter module and the predetermined target voltage is less than a predetermined threshold, the controller causes the power inverter module to switch from a stop mode to an operating mode and causes the propulsion system to switch from a stop mode to an operating mode.

[0030] Option 5. The power control system according to Option 1, wherein when the propulsion system is stopped, the controller is configured to cause the output voltage of the DC-DC converter to ramp down to a voltage less than a first predetermined threshold.

[0031] Option 6. The power control system according to Option 5, wherein when the output voltage of the DC-DC converter is less than the first predetermined threshold, the controller causes the power inverter module to switch from the operating mode to the stop mode and causes the DC-DC converter to switch from the operating mode to the standby mode.

[0032] Option 7. The power control system according to Option 6, wherein the controller is configured to disconnect the energy storage system and cause the propulsion system to switch from an operating mode to a stop mode when the input voltage of the DC-DC converter is less than a second predetermined threshold.

[0033] Option 8. The power control system according to Option 1 further includes a bidirectional bypass switch connected between the power inverter module and the energy storage system.

[0034] Option 9. The power control system according to Option 8, wherein the controller is configured to close the bidirectional bypass switch and simultaneously precharge the first capacitor and the second capacitor.

[0035] Option 10. The power control system according to Option 9, wherein, in response to the difference between the voltage across the pre-charge resistor in the energy storage system and the voltage of the first capacitor being less than a first predetermined threshold, the controller selectively switches the energy storage system to a normal mode and disconnects the bidirectional bypass switch.

[0036] Option 11. The power control system according to Option 10, wherein:

[0037] The controller determines the difference between the output voltage of the DC-DC converter and the input voltage of the power inverter module;

[0038] When the difference exceeds a predetermined threshold, the controller incrementally adjusts the output voltage of the DC-DC converter by an incremental voltage; and

[0039] When the difference is less than a predetermined threshold, the controller causes the power inverter module to switch from a stop mode to an operating mode and the propulsion system to switch from a shut-off mode to an active mode.

[0040] Option 12. The power control system according to Option 8, wherein when the propulsion system is in operating mode, the bidirectional bypass switch is closed and the DC-DC converter is in standby mode, the controller is configured to stop the propulsion system by the following steps:

[0041] Disconnect the energy storage system; and

[0042] When the output voltage of the DC-DC converter and the power inverter module is less than a first predetermined threshold, the power inverter module is switched from the operating mode to the stop mode.

[0043] Option 13. The power control system according to Option 12, wherein when the voltage across the first capacitor and the second capacitor is less than a second predetermined threshold, the controller causes the propulsion system to switch from the operating mode to the off mode.

[0044] Option 14. A power control system for a vehicle propulsion system, the power control system comprising:

[0045] An energy storage system, which includes a pre-charging circuit and one or more battery packs;

[0046] A DC-DC converter connected to the energy storage system and including a first capacitor, a first plurality of power switches and an inductor;

[0047] A power inverter module, connected to the DC-DC converter and including a second capacitor and a second plurality of power switches; and

[0048] The controller is constructed as follows:

[0049] The first capacitor of the DC-DC converter is pre-charged;

[0050] To switch the DC-DC converter from standby mode to operating mode; and

[0051] Determine the difference between the output voltage of the DC-DC converter and the input voltage of the power inverter module:

[0052] When the difference exceeds a first predetermined threshold, the output voltage of the DC-DC converter is ramped up; and

[0053] When the difference is less than the first predetermined threshold, the power inverter module is switched from stop mode to run mode and the propulsion system is switched from shut-off mode to active mode.

[0054] Option 15. The power control system according to Option 14, wherein when the propulsion system is stopped, the controller is configured to:

[0055] Selectively slop the output voltage of the DC-DC converter;

[0056] When the output voltage of the DC-DC converter is less than a second predetermined threshold, the power inverter module is switched from the operating mode to the stop mode and the DC-DC converter is switched from the operating mode to the standby mode.

[0057] Disconnect the energy storage system; and

[0058] When the input voltage of the DC-DC converter is less than a third predetermined threshold, the propulsion system is switched from the operating mode to the stop mode.

[0059] Option 16. A power control system for a vehicle propulsion system, the power control system comprising:

[0060] An energy storage system, which includes a pre-charging circuit and one or more battery packs;

[0061] A DC-DC converter connected to the energy storage system includes a first capacitor, a first plurality of power switches, an inductor, and a bidirectional bypass switch.

[0062] A power inverter module, which is connected to the DC-DC converter and includes a second capacitor and a second plurality of power switches;

[0063] A bidirectional bypass switch connected between the power inverter module and the energy storage system; and

[0064] The controller is constructed as follows:

[0065] Close the bidirectional bypass switch and simultaneously precharge the first capacitor and the second capacitor; and

[0066] After pre-charging the first capacitor and the second capacitor, the DC-DC converter is switched from standby mode to operating mode.

[0067] Option 17. The power control system according to Option 16, wherein the controller is configured to calculate the difference between the output voltage of the DC-DC converter and the input voltage of the power inverter module.

[0068] Option 18. The power control system according to Option 17, wherein:

[0069] When the difference exceeds a predetermined threshold, the controller is configured to incrementally adjust the output voltage of the DC-DC converter by an incremental voltage; and

[0070] When the difference is less than the predetermined threshold, the controller is configured to switch the power inverter module from a stop mode to an operating mode and the propulsion system from a shut-off mode to an active mode.

[0071] Option 19. The power control system according to Option 16, wherein when the propulsion system is in operating mode, the bidirectional bypass switch is closed and the DC-DC converter is in standby mode, the controller is configured to stop the propulsion system by the following steps:

[0072] Disconnect the energy storage system; and

[0073] When the output voltage of the DC-DC converter and the input voltage of the power inverter module are less than a first predetermined threshold, the power inverter module is switched from the operating mode to the stop mode.

[0074] Option 20. The power control system according to Option 19, wherein when the voltage of the first capacitor and the second capacitor is less than a second predetermined threshold, the controller causes the propulsion system to switch from the operating mode to the shutdown mode.

[0075] Further applicability of this disclosure will become apparent from the detailed description, claims, and drawings. The detailed description and specific examples are intended for illustrative purposes only and are not intended to limit the scope of this disclosure. Attached Figure Description

[0076] This disclosure will be more fully understood from the detailed description and accompanying drawings, in which:

[0077] Figure 1 These are functional block diagrams and electrical schematic diagrams of an example power control system for a battery system for a vehicle according to the present disclosure, the power control system including a DC-DC converter;

[0078] Figure 2 yes Figure 1 Functional block diagram and electrical schematic diagram of an example power inverter module of a power control system;

[0079] Figure 3 This is a functional block diagram of an example controller for a power control system according to the present disclosure;

[0080] Figure 4 This is a flowchart illustrating an example of a method for pre-charging capacitors of a DC-DC converter and a power inverter module without using a bypass switch, according to the present disclosure, where "F" represents "false" or "no" and "T" represents "true" or "yes".

[0081] Figure 5 This is a flowchart illustrating an example of a method for pre-charging capacitors of a DC-DC converter and a power inverter module using a bypass switch, according to the present disclosure, where "F" represents "false" or "no" and "T" represents "true" or "yes".

[0082] Figure 6 This is a flowchart illustrating an example of a method for shutting off the capacitors of a DC-DC converter and a power inverter module without using a bypass switch, according to the present disclosure, where "F" represents "false" or "no" and "T" represents "true" or "yes"; and

[0083] Figure 7 This is a flowchart illustrating an example of a method for shutting off the capacitors of a DC-DC converter and a power inverter module when using a bypass switch, according to the present disclosure, where "F" represents "false" or "no" and "T" represents "true" or "yes".

[0084] In the accompanying drawings, reference numerals may be reused to identify similar and / or identical elements. Detailed Implementation

[0085] When an electric vehicle is started, components of the power control system (such as the DC-DC converter or power inverter module (PIM)) may be damaged by high inrush currents. Care must also be taken when shutting down the power control system to avoid damage. The power control system according to this disclosure controls the charging and discharging of the capacitors of the DC-DC converter and the PIM during startup and shutdown, respectively, to avoid damage to the components of the power control system.

[0086] Now for reference Figure 1A power control system 10 is shown. While a particular power control system is shown for illustrative purposes, power control systems can be constructed differently depending on the details of a given system. The power control system 10 in this example includes a charging port 12 and supplies power to a first vehicle load 18 (such as an auxiliary power module (APM), an AC compressor module (ACCM), and / or other loads), a power inverter module (PIM) 22, and / or other vehicle loads. The power control system 10 further includes a contactor 32, a rechargeable energy storage system (RESS) 34, and a DC-DC converter 36. The DC-DC converter 36 can operate as a buck converter, a boost converter, or a buck-boost converter.

[0087] In this example, contactor 32 includes resistor R. PC The contactor 32 further includes switches S1 and S3, which have a first terminal connected to the positive terminal of the charging port 12.

[0088] In this example, RESS 34 includes battery pack 14 and switches SPC, S5, and S6. The pre-charge circuit includes switch S6 and resistor R. PC And switch SPC. The first terminal of switch SPC and the first terminal of S5 are connected to the second terminal of switch S1. The second terminal of switch SPC is connected to resistor R. PC The second terminal of switch S5 is connected to the first terminal of fuse F1. The second terminal of fuse F1 is connected to the positive terminal of battery pack 14, which includes one or more battery cells. The negative terminal of battery pack 14 is connected to the first terminal of switch S6. The second terminal of switch S6 is connected to the second terminal of switch S2.

[0089] In some examples, the DC-DC converter 36 may include a buck-boost converter. The DC-DC converter 36 includes a capacitor C1 having a first terminal connected to a first terminal of switch S1 and a second terminal connected to a second terminal of switch S2. The first terminal of power switch T1 is connected to the second terminal of switch S1 and the first terminal of bidirectional bypass switch S0. The second terminal of power switch T1 is connected to the first terminal of inductor L1 and the first terminal of power switch T3. The second terminal of power switch T3 is connected to the second terminal of switch S2.

[0090] The second terminal of the bidirectional bypass switch S0 is connected to the first terminal of power switch T2, the second terminal of switch S3, the first terminal of switch S12, and the first terminal of fuse F2. The second terminal of power switch T2 is connected to the second terminal of inductor L1 and the first terminal of power switch T4. The second terminal of power switch T4 is connected to the second terminal of switch S2, the second terminal of the first vehicle load 18, and the first terminal of switch S11.

[0091] The second terminal of fuse F2 is connected to the first terminal of switch S10. The second terminal of switch S10 is connected to power inverter module 22. The second terminal of power inverter module 22 is connected to the second terminals of switch S11 and switch S4.

[0092] Although specific embodiments of the contactor 32, energy storage system (RESS) 34, and DC-DC converter 36 are shown for illustrative purposes, other embodiments may also be used.

[0093] Now for reference Figure 2 An example of a power inverter module (PIM) 22 is shown. The power inverter module 22 includes a capacitor C2 and power switches T5 and T6, T7 and T8, and T9 and T10. The first terminal of capacitor C2 is connected to the first terminals of switches T5, T7, and T9. The second terminals of these power switches are connected to the second terminals of capacitor C2. The second terminal of power switch T5 is connected to the first terminal of power switch T6 and the first phase of motor M. The second terminal of power switch T7 is connected to the first terminal of power switch T8 and the second phase of motor M. The second terminal of power switch T9 is connected to the first terminal of power switch T10 and the third phase of motor M. Although a single inverter and PIM are shown, an electric vehicle may include one or more additional PIMs and / or inverters.

[0094] Now for reference Figure 3 The controller 60 executes an application configured to control the power switch 68 of the DC-DC converter 36, the power inverter module 22, and switches 64 (including switches S1 to S12 and SPC) based on inputs from sensors 66 (such as current, voltage, temperature, speed, torque, and other sensors), the user interface 72, the propulsion system 73, other vehicle systems 74, or other inputs. Although a single controller 60 is shown, one or more controllers may be used.

[0095] In some examples, the voltage sensor includes: a first voltage sensor VS1 ( Figure 1 Its sensing resistor R PC The voltage at both ends (pre-charge voltage); the second voltage sensor VS2 ( Figure 1), which senses the voltage at the input of the DC-DC converter 36 (the voltage across capacitor C1); the third voltage sensor VS3 ( Figure 1 ), which senses the voltage at the output of the DC-DC converter 36; the fourth voltage sensor VS4 ( Figure 2 ), which senses the voltage at the input of PIM 22; and the fifth voltage sensor VS5 ( Figure 2 ), which senses the voltage across capacitor C2.

[0096] Now for reference Figure 4 A method 110 is shown for pre-charging the capacitors of DC-DC converter 36 and PIM 22 without using a bypass switch. During pre-charging, controller 60 causes switches SPC and S6 to close to charge capacitor C1 and / or other capacitors in PIM 22 and / or load 18.

[0097] At 114, the method determines whether the power control system does not include a bypass switch (or whether the bypass switch is off or open). If 114 is true, the method continues at 118, and the method sets the DC-DC converter 36 and PIM 22 to standby mode. At 122, the method determines whether the propulsion system has been commanded to be turned on. If true, the method precharges capacitor C1 (e.g., by closing...). Figure 1 Switches SPC and S6 in the circuit are used to charge capacitor C1.

[0098] This method determines the resistor R PC Voltage V across the terminals PC The voltage V at the input of the DC-DC converter 36 DCDCIn The method adjusts the voltage level at 134 to ensure that the voltage level is within the range of the input voltages. When this difference is less than a first predetermined threshold, the method switches the mode of RESS 34 from pre-charge to normal mode (by disconnecting SPC and closing S5) and switches the mode of DC-DC converter 36 to operation. At 138, the output of DC-DC converter 36 is incrementally increased to appropriately charge the capacitors in the power inverter module. For example, the voltage is controlled to provide a ramp, step, or monotonic increase. In other words, pulse width modulation (PWM) of the switches in DC-DC converter 36 is used to move the output of DC-DC converter 36 from an initial voltage (which may be zero or non-zero) toward a target voltage level (V). PIM_dc_target () gradually increase.

[0099] When the voltage at the PIM input (or V) PIM_dc ) and V PIM_dc_targetWhen the difference between them is within the second predetermined threshold (TH2) (as determined at 142), the method continues at 146 and switches the mode of PIM 22 to operation and the mode of the propulsion system to action.

[0100] Now for reference Figure 5 A method 210 is shown for pre-charging the capacitors of DC-DC converter 36 and PIM 22 during startup when the power control system includes a bypass switch S0 (commanded to be turned on or closed). At 214, the method determines whether the power control system includes a bypass switch S0. If 214 is true, the method continues at 218 and sets the mode of DC-DC converter 36 and PIM 22 to standby. At 222, the method determines whether the propulsion system has been enabled. If 222 is true, the method enables or closes the bypass switch S0. At 230, the method determines whether the bypass switch S0 is enabled or closed.

[0101] If 230 is true, the method at 234 precharges capacitors C1 and C2 by closing switches SPC and S6 to charge both capacitors C1 and C2. At 235, the method determines whether the difference between VPC and VAll_DC is less than a predetermined threshold TH. If 235 is true, the method continues at 236, and transitions RESS 34 to normal mode (disconnects SPC and closes S5) and disables (or disconnects) the bypass switch.

[0102] At 238, the method switches the DC-DC converter 36 to operation mode. This method increases the voltage at the output of the DC-DC converter 36 (e.g., ramp, step, or monotonic) to controllably increase the voltage across the capacitor.

[0103] For example, the voltage (initially V at the end of 234) can be... RESS Adjust + / - Delta_V. Repeat these voltage steps until the voltage across capacitor C2 equals the desired DC-DC output voltage (this desired DC-DC output voltage can be greater than or less than V). RESS At position 242, the method determines V. DCDC_out (Target voltage output of DC-DC converter 36) minus V PIM_dc Is the voltage across capacitor C2 less than the third threshold TH3? If 242 is true, then PIM 22 is set to run and the propulsion system is set to active.

[0104] Now for reference Figure 6The diagram illustrates a method 310 for shutting off the capacitors of DC-DC converter 36 and PIM 22 when bypass switch S0 is open or not in use. At 314, the method determines whether the power control system does not include bypass switch S0. If 314 is true, the method continues at 318, setting the mode of PIM 22 to running and the mode of the propulsion system to active. At 322, the method determines whether the mode of the propulsion system transitions to stop.

[0105] If 322 is true, then this method sets the output of DC-DC converter 36 to ramp down from the current voltage. When the inverter voltage (V PIM_dc When the value is less than the fourth threshold (TH4), the method continues at 334, setting PIM 22 to stop mode and DC-DC converter 36 to standby mode. At 338, RESS 34 is disconnected using S5 and S6. When V DCDCIn When the value is less than the fifth threshold TH5, the propulsion system is cut off at point 346.

[0106] Now for reference Figure 7 The diagram illustrates a method 410 for shutting off the capacitors of DC-DC converter 36 and PIM 22 when bypass switch S0 is turned on. At 418, the mode of PIM 22 is set to running and the mode of the propulsion system is set to active. At 426, the method determines whether the mode of the propulsion system has changed to stop. If 426 is true, the method determines whether bypass is true and whether DC-DC converter 36 is in standby mode.

[0107] If 426 is true, then use S5 and S6 to disconnect RESS 34. When All_DC(V PIM_dc and / or V DCDCIN When the value is less than the sixth threshold TH6, the propulsion system mode is set to stop at point 442. At point 446, the method determines V. All_DC(Caps) If the voltage across capacitors C1 and C2 is less than the seventh threshold TH7, the propulsion system mode will be set to off at 450.

[0108] The foregoing description is merely illustrative in nature and is in no way intended to limit this disclosure, its application, or use. The broad teachings of this disclosure can be implemented in various forms. Therefore, while this disclosure includes specific examples, its true scope should not be so limited, as other modifications will become apparent upon examination of the drawings, specification, and the following claims. It should be understood that one or more steps within the method may be performed in a different order (or simultaneously) without altering the principles of this disclosure. Furthermore, while each of the embodiments described above is described as having certain features, any one or more of those features described with respect to any embodiment of this disclosure may be implemented and / or combined with features of any other embodiment, even if such combination is not explicitly described. In other words, the described embodiments are not mutually exclusive, and the arrangement of one or more embodiments with each other remains within the scope of this disclosure.

[0109] Spatial and functional relationships between components (e.g., between modules, circuit elements, semiconductor layers, etc.) are described using various terms, including “connection,” “joint,” “link,” “adjacent,” “closely adjacent,” “on top of,” “above,” “below,” and “set.” Unless explicitly described as “direct,” when describing the relationship between the first and second components in the above disclosure, the relationship can be a direct relationship in which no other intervening components exist between the first and second components, or it can be an indirect relationship (spatially or functionally) between the first and second components. As used herein, at least one of the phrases A, B, and C should be interpreted using non-exclusive logic or signifying logic (A or B or C) and should not be interpreted as meaning “at least one of A, at least one of B, and at least one of C.”

[0110] In the accompanying drawings, the direction of the arrows generally illustrates the flow of information of interest (such as data or instructions). For example, when components A and B exchange various types of information, but the information transmitted from component A to component B is relevant to the illustration, the arrow may point from component A to component B. This unidirectional arrow does not imply that no other information is transmitted from component B to component A. Furthermore, for information sent from component A to component B, component B may send a request for the information to component A or receive acknowledgment of the information.

[0111] In this application (including the definitions below), the term "module" or "controller" may be replaced by the term "circuit". The term "module" may refer to, be part of, or include the following: application-specific integrated circuit (ASIC); digital, analog, or mixed-signal analog / digital discrete circuit; digital, analog, or mixed-signal analog / digital integrated circuit; combinational logic circuit; field-programmable gate array (FPGA); processor circuitry (shared, dedicated, or grouped) that executes code; memory circuitry (shared, dedicated, or grouped) that stores code executed by the processor circuitry; other suitable hardware components that provide the described functionality; or combinations of some or all of the above, such as in a system-on-a-chip.

[0112] A module may include one or more interface circuits. In some examples, the interface circuits may include wired or wireless interfaces connected to a local area network (LAN), the Internet, a wide area network (WAN), or a combination thereof. The functionality of any given module of this disclosure may be distributed among multiple modules connected via the interface circuits. For example, multiple modules may allow for load balancing. In further examples, a server (also referred to as a remote or cloud) module may perform a function on behalf of a client module.

[0113] As used above, the term code may include software, firmware, and / or microcode, and may refer to programs, routines, functions, classes, data structures, and / or objects. The term shared processor circuitry covers a single processor circuit that executes some or all of the code from multiple modules. The term group processor circuitry covers a processor circuit that, in combination with additional processor circuitry, executes some or all of the code from one or more modules. References to multiple processor circuits cover multiple processor circuits on a discrete die, multiple processor circuits on a single die, multiple cores of a single processor circuit, multiple threads of a single processor circuit, or a combination of the above. The term shared memory circuitry covers a single memory circuit that stores some or all of the code from multiple modules. The term group memory circuitry covers a memory circuit that, in combination with additional memory, stores some or all of the code from one or more modules.

[0114] The term memory circuit is a subset of the term computer-readable medium. As used herein, the term computer-readable medium does not cover transient electrical or electromagnetic signals propagating through a medium (such as a carrier wave); therefore, the term computer-readable medium can be considered tangible and non-transitory. Non-limiting examples of non-transitory, tangible computer-readable media are non-volatile memory circuits (such as flash memory circuits, erasable programmable read-only memory circuits, or mask read-only memory circuits), volatile memory circuits (such as static random access memory circuits or dynamic random access memory circuits), magnetic storage media (such as analog or digital magnetic tape or hard disk drives), and optical storage media (such as CDs, DVDs, or Blu-ray discs).

[0115] The apparatus and methods described in this application can be implemented, in part or in whole, by a special-purpose computer created by causing a general-purpose computing mechanism to perform one or more specific functions embodied in a computer program. The function blocks, flowchart components, and other elements described above serve as software specifications that can be converted into computer programs through the routine work of skilled technicians or programmers.

[0116] A computer program includes processor-executable instructions stored on at least one non-transitory, tangible, computer-readable medium. A computer program may also include or depend on stored data. A computer program may encompass a basic input / output system (BIOS) for interacting with the hardware of a special-purpose computer, device drivers for interacting with specific devices of a special-purpose computer, one or more operating systems, user applications, background services, background applications, etc.

[0117] Computer programs may include: (i) descriptive text to be parsed, such as HTML (Hypertext Markup Language), XML (Extensible Markup Language), or JSON (JavaScript Object Notation); (ii) assembly code; (iii) object code generated from source code by a compiler; (iv) source code executed by an interpreter; and (v) source code compiled and executed by a just-in-time (JIT) compiler, etc. As an example only, source code can be written in languages ​​including C, C++, C#, Objective-C, Swift, Haskell, Go, SQL, R, Lisp, Java®, Fortran, Perl, Pascal, Curl, OCaml, JavaScript®, HTML5 (Hypertext Markup Language version 5), Ada, ASP (Dynamic Server Web Pages), PHP (PHP: Hypertext Preprocessing Language), Scala, Eiffel, Smalltalk, Erlang, Ruby, Flash®, Visual Basic®, Lua, MATLAB, SIMULINK, and Python®.

Claims

1. A power control system for a vehicle propulsion system, the power control system comprising: An energy storage system, which includes a pre-charging circuit and one or more battery packs; A DC-DC converter connected to the energy storage system and including a first capacitor, a first plurality of power switches and an inductor; A power inverter module, which is connected to the DC-DC converter and includes a second capacitor and a second plurality of power switches; A bidirectional bypass switch is connected between the power inverter module and the energy storage system; as well as The controller is constructed as follows: Close the bidirectional bypass switch and simultaneously precharge the first capacitor of the DC-DC converter and the second capacitor of the power inverter module; as well as Control the operating modes of the DC-DC converter and the power inverter module; In response to the difference between the voltage across the pre-charge resistor in the energy storage system and the voltage of the first capacitor being less than a first predetermined threshold, the controller selectively switches the energy storage system to a normal mode and disconnects the bidirectional bypass switch.

2. The power control system according to claim 1, wherein, The controller is configured to: after pre-charging the first capacitor of the DC-DC converter, control the output voltage of the DC-DC converter to ramp up the voltage across the second capacitor of the power inverter module, thereby pre-charging the second capacitor.

3. The power control system according to claim 1, wherein, The controller is configured to: after pre-charging the first capacitor of the DC-DC converter, switch the DC-DC converter from standby mode to operating mode and control the output voltage of the DC-DC converter to ramp up the voltage across the second capacitor of the power inverter module, thereby pre-charging the second capacitor.

4. The power control system according to claim 1, wherein, When the difference between the input voltage of the power inverter module and the predetermined target voltage is less than a predetermined threshold, the controller causes the power inverter module to switch from a stop mode to an operating mode and the propulsion system to switch from a stop mode to an operating mode.

5. The power control system according to claim 1, wherein, When the propulsion system is stopped, the controller is configured to cause the output voltage of the DC-DC converter to ramp down to a voltage less than a first predetermined threshold.

6. The power control system according to claim 5, wherein, When the output voltage of the DC-DC converter is less than the first predetermined threshold, the controller causes the power inverter module to switch from the operating mode to the stop mode and the DC-DC converter to switch from the operating mode to the standby mode.

7. The power control system according to claim 6, wherein, The controller is configured to disconnect the energy storage system and to switch the propulsion system from an operating mode to a stopped mode when the input voltage of the DC-DC converter is less than a second predetermined threshold.

8. The power control system according to claim 1, wherein: The controller determines the difference between the output voltage of the DC-DC converter and the input voltage of the power inverter module; When the difference exceeds a predetermined threshold, the controller incrementally adjusts the output voltage of the DC-DC converter by an incremental voltage; and When the difference is less than a predetermined threshold, the controller causes the power inverter module to switch from a stop mode to an operating mode and the propulsion system to switch from a shut-off mode to an active mode.

9. The power control system according to claim 1, wherein, When the propulsion system is in operating mode, the bidirectional bypass switch is closed and the DC-DC converter is in standby mode, the controller is configured to stop the propulsion system by the following steps: Disconnect the energy storage system; as well as When the output voltage of the DC-DC converter and the power inverter module is less than a first predetermined threshold, the power inverter module is switched from the operating mode to the stop mode.

10. The power control system according to claim 9, wherein, When the voltage across the first capacitor and the second capacitor is less than a second predetermined threshold, the controller causes the propulsion system to switch from the operating mode to the off mode.

11. A power control system for a vehicle propulsion system, the power control system comprising: An energy storage system, which includes a pre-charging circuit and one or more battery packs; A DC-DC converter connected to the energy storage system and including a first capacitor, a first plurality of power switches and an inductor; A power inverter module, which is connected to the DC-DC converter and includes a second capacitor and a second plurality of power switches; A bidirectional bypass switch is connected between the power inverter module and the energy storage system; as well as The controller is constructed as follows: Close the bidirectional bypass switch and simultaneously precharge the first capacitor of the DC-DC converter; To switch the DC-DC converter from standby mode to operating mode; and Determine the difference between the output voltage of the DC-DC converter and the input voltage of the power inverter module: When the difference is greater than a first predetermined threshold, the output voltage of the DC-DC converter is changed in a ramp manner; as well as When the difference is less than the first predetermined threshold, the power inverter module is switched from the stop mode to the run mode and the propulsion system is switched from the shut-off mode to the active mode. In response to the difference between the voltage across the pre-charge resistor in the energy storage system and the voltage of the first capacitor being less than a first predetermined threshold, the controller selectively switches the energy storage system to a normal mode and disconnects the bidirectional bypass switch.

12. The power control system according to claim 11, wherein, When the propulsion system is stopped, the controller is configured to: Selectively slop the output voltage of the DC-DC converter; When the output voltage of the DC-DC converter is less than a second predetermined threshold, the power inverter module is switched from the operating mode to the stop mode and the DC-DC converter is switched from the operating mode to the standby mode. Disconnect the energy storage system; as well as When the input voltage of the DC-DC converter is less than a third predetermined threshold, the propulsion system is switched from the operating mode to the stop mode.

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