Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L1/00—Supplying electric power to auxiliary equipment of vehicles
  • B60L1/003—Supplying electric power to auxiliary equipment of vehicles to auxiliary motors, e.g. for pumps, compressors
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L3/00—Electric devices on electrically-propelled vehicles for safety purposes; Monitoring operating variables, e.g. speed, deceleration or energy consumption
  • B60L3/0023—Detecting, eliminating, remedying or compensating for drive train abnormalities, e.g. failures within the drive train
  • B60L3/0046—Detecting, eliminating, remedying or compensating for drive train abnormalities, e.g. failures within the drive train relating to electric energy storage systems, e.g. batteries or capacitors
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L50/00—Electric propulsion with power supplied within the vehicle
  • B60L50/10—Electric propulsion with power supplied within the vehicle using propulsion power supplied by engine-driven generators, e.g. generators driven by combustion engines
  • B60L50/16—Electric propulsion with power supplied within the vehicle using propulsion power supplied by engine-driven generators, e.g. generators driven by combustion engines with provision for separate direct mechanical propulsion
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
  • B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
  • B60L58/12—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries responding to state of charge [SoC]
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
  • B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
  • B60L58/12—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries responding to state of charge [SoC]
  • B60L58/14—Preventing excessive discharging
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
  • B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
  • B60L58/12—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries responding to state of charge [SoC]
  • B60L58/15—Preventing overcharging
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
  • B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
  • B60L58/18—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries of two or more battery modules
  • B60L58/20—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries of two or more battery modules having different nominal voltages
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
  • B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
  • B60L58/18—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries of two or more battery modules
  • B60L58/22—Balancing the charge of battery modules
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L7/00—Electrodynamic brake systems for vehicles in general
  • B60L7/10—Dynamic electric regenerative braking
  • B60L7/14—Dynamic electric regenerative braking for vehicles propelled by AC motors
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
  • B60R16/00—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for
  • B60R16/02—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for electric constitutive elements
  • B60R16/03—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for electric constitutive elements for supply of electrical power to vehicle subsystems or for
  • B60R16/033—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for electric constitutive elements for supply of electrical power to vehicle subsystems or for characterised by the use of electrical cells or batteries
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
  • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
  • H02J7/14—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from dynamo-electric generators driven at varying speed, e.g. on vehicle
  • H02J7/1423—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from dynamo-electric generators driven at varying speed, e.g. on vehicle with multiple batteries
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L2210/00—Converter types
  • B60L2210/30—AC to DC converters
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L2210/00—Converter types
  • B60L2210/40—DC to AC converters
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L2240/00—Control parameters of input or output; Target parameters
  • B60L2240/10—Vehicle control parameters
  • B60L2240/12—Speed
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
  • B60L2260/00—Operating Modes
  • B60L2260/20—Drive modes; Transition between modes
  • B60L2260/26—Transition between different drive modes
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
  • H02J2310/00—The network for supplying or distributing electric power characterised by its spatial reach or by the load
  • H02J2310/40—The network being an on-board power network, i.e. within a vehicle
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
  • H02J2310/00—The network for supplying or distributing electric power characterised by its spatial reach or by the load
  • H02J2310/40—The network being an on-board power network, i.e. within a vehicle
  • H02J2310/46—The network being an on-board power network, i.e. within a vehicle for ICE-powered road vehicles
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T10/00—Road transport of goods or passengers
  • Y02T10/60—Other road transportation technologies with climate change mitigation effect
  • Y02T10/70—Energy storage systems for electromobility, e.g. batteries
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T10/00—Road transport of goods or passengers
  • Y02T10/60—Other road transportation technologies with climate change mitigation effect
  • Y02T10/7072—Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T10/00—Road transport of goods or passengers
  • Y02T10/60—Other road transportation technologies with climate change mitigation effect
  • Y02T10/72—Electric energy management in electromobility

Definitions

• the present invention relates to a power system for a vehicle, which includes a first battery, a second battery and a generator that charges the first and second batteries.
• a known power system installed in a vehicle is configured by using two batteries, e.g. a lead battery (first battery) and a lithium ion battery (second battery). Using these batteries properly, electric power is supplied to various electrical loads installed in the vehicle.
• a patent document JP-A-2012-080706 discloses a configuration of such a power system.
• a lithium ion battery is electrically connected to a generator and a lead battery via a connection switch configured by a semiconductor switch.
• the connection switch In regenerative generation of the generator associated with deceleration of the vehicle, the connection switch is turned on to enable power supply to the lithium ion battery from the generator. Also, in non-regenerative generation, the connection switch is turned off, so that electric power is ensured to be supplied from the lithium ion battery to electrical loads which establish electrical connection on a lithium ion battery side with respect to the connection switch. Controlling the connection switch as mentioned above, the electrical energy generated by regenerative generation can be efficiently used.
• the lead battery and the lithium ion battery may have a different terminal voltage, i.e. the terminal voltage of the lead battery may be made higher than that of the lithium ion battery.
• the lithium ion battery can be charged in preference to the lead battery.
• the connection switch is turned on in regenerative generation to charge both of the lead battery and the lithium ion battery, an unintentional situation would occur.
• the state of the lead battery may transition from a charging state to a discharging state to unintentionally decrease the amount of charge (residual capacity) of the lead battery.
• electrical charge is applied from the lead battery to the lithium ion battery and thus the amount of charge of the lead battery decreases.
• An embodiment provides a power system for a vehicle which includes a first battery, a second battery, and a connection switch that electrically connects and disconnects the first and second batteries to realize efficient application of electrical charge to the first and second batteries.
• a power system for a vehicle which includes: a generator; a first battery and a second battery which are connected in parallel with the generator; and a connection switch which is provided on a connection line electrically connecting the first and second batteries, and which electrically connects and electrically disconnects the first battery and the generator to/from the second battery.
• the power system performs regenerative generation by the generator when the vehicle decelerates.
• a terminal voltage of the first battery is made larger than a terminal voltage of the second battery.
• the power system further includes: a first control means which makes the connection switch an electrically connected state to apply electrical charge to both of the first battery and the second battery during regenerative generation by the generator; a discharge monitor means which monitors a discharging state of the first battery during regenerative generation; and a second control means , which disconnects the connection switch based on the discharging state of the first battery monitored by the discharge monitor means during regenerative generation.
• Fig. 2 is a flow diagram illustrating a procedure of a charge control process
• Fig. 3 is a diagram illustrating lead battery state of charge PbSOC relative to turn-on vehicle speed and turn-off vehicle speed;
• Fig. 4 is a diagram illustrating PbSOC relative to discharge permission value
• Fig. 5 is a time diagram illustrating a state of charge of batteries in regenerative generation.
• Fig. 6 is a diagram illustrating PbSOC and lithium battery state of charge LiSOC relative to turn-off vehicle speed.
• the power system of the present embodiment is applied to a vehicle that has an engine (internal combustion engine).
• the power system includes two batteries, i.e. a lead battery and a lithium ion battery, and a generator that charges these batteries.
• the alternator 11 is connected to the crank shaft (output shaft) of the engine to generate power with the rotational energy of the crank shaft.
• AC current is induced in the stator coil in response to excitation current that passes through the rotor core.
• the AC current is converted to DC current by a rectifier.
• the excitation current passing through the rotor coil is regulated by a regulator to thereby adjust the voltage of the generated DC current to a set voltage Vreg.
• the regulator of the alternator 11 is controlled by an engine controller 30 (first control means, discharge monitor means, second control means, reference value setting means, prohibition vehicle speed setting means, permission vehicle speed setting means).
• the battery unit 14 is provided with an input terminal 16 and an output terminal 17, ⁇ which are connected to each other via a power feeder 18.
• the alternator 11 and the lead battery 12 are connected to the input terminal 16.
• Electrical loads 19, to which power is supplied from the lithium ion battery 13, are connected to the output terminal 17.
• Specific examples of the electrical loads 19 include constant-current loads, such as a navigation system and an audio system, which are driven with constant current.
• the MOS switch 21 is a semiconductor switch configured by a MOSFET (metal oxide semiconductor field effects transistor).
• the MOS switch 21 is provided between the input and output terminals 16 and 17.
• the MOS switch 21 functions as a switch that electrically connects (turns on) and electrically disconnects (turns off) the lithium ion battery 13 to/from the alternator 11 and the lead battery 12.
• the SMR switch 22 is a semiconductor switch configured by a MOSFET.
• the SMR switch 22 is arranged between a connecting point (indicated by XI in Fig. 1) and the lithium ion battery 13, the connecting point connecting between the MOS switch 21 and the output terminal 17.
• the SMR switch 22 functions as a switch that electrically connects (turns on) and electrically disconnects (turns off) the lithium ion battery 13 to/from a power feed path that connects between the input and output terminals 16 and 17.
• the SMR switch 22 also functions as an opening/closing means in a time of emergency. Normally, or, in periods other than a time of emergency, the SMR switch 22 is retained to be a state of being turned on (on state) by an on signal sent from the battery controller 23. In a time of emergency as exemplified below, the output of the on signal is stopped to bring the SMR switch 22 into a state of being turned off (off state). By bringing the SMR switch 22 into an off state, overcharge or overdischarge of the lithium ion battery 13 is avoided. For example, in the event that the regulator provided at the alternator 11 breaks down to abnormally raise the set voltage Vreg, the lithium ion battery 13 may be overcharged.
• the on state and the off state of the MOS switch 21 and the SMR switch 22 are constantly monitored by the battery controller 23.
• the results of the monitoring are transmitted from the battery controller 23 to other components, such as the engine controller 30, at predetermined intervals.
• the electric power generated by the alternator 11 is supplied to various in-vehicle electrical loads, while being supplied to the lead battery 12 and the lithium ion battery 13.
• electric power is supplied from the lead battery 12 and the lithium ion battery 13 to the in-vehicle electrical loads.
• An amount of discharge from the lead battery 12 and the lithium ion battery 13 to the in-vehicle electrical loads and an amount of charge applied from the alternator 11 to the batteries 12 and 13 are controlled so that SOC (state of charge: percentage (%) of an actual amount of charge with respect to an amount of charge in a fully-charged state) of the batteries 12 and 13 will fall in a rage that would not cause overcharge or overdischarge (proper range).
• the engine controller 30 is ensured to control the set voltage Vreg so as not to cause overcharge or overdischarge, while the battery controller 23 is ensured to control the operation of the MOS switch 21.
• the MOS switch 21 and the SMR switch 22 are both turned on to charge both of the lead battery 12 and the lithium ion battery 13.
• terminal voltages of the lead battery 12 and the lithium ion battery 13 are determined such that the terminal voltage of the battery 12 is higher than that of the battery 13. Accordingly, in a state where the switches 21 and 22 are turned on for mutual electrical connection of the batteries 12 and 13, the lithium ion battery 13 is ensured to be charged by both the alternator 11 and the lead battery 12.
• the engine controller 30 has an idle reduction function that automatically stops the engine when predetermined automatic stop conditions are met while the vehicle runs, and automatically restarts the engine when predetermined restart conditions are met while the engine is automatically stopped.
• the automatic stop conditions include, for example, that: the vehicle speed is not more than a predetermined level; and the manipulated variable of the accelerator is zero (or the brake is applied).
• the engine restart conditions include, for example, that: the accelerator has been manipulated; and the brake has been released.
• the battery controller 23 brings both of the MOS switch 21 and the SMR switch 22 into an on state, so that the lithium ion battery 13 is charged (regeneratively charged) while the engine revolution decreases.
• the battery controller 23 brings the MOS switch 21 into an off state from an on state, so that the starter 15a is driven by the electric power supplied from the lead battery 12 under the condition where the lead battery 12 is electrically disconnected from the lithium ion battery 13.
• the discharging state of the lead battery 12 is ensured to be monitored during regenerative generation and the MOS switch 21 is ensured to be turned off (electrically disconnected) based on the discharging state.
• control of charge/discharge of the batteries during regenerative generation is specifically described.
• step Sll it is determined, in step Sll, whether or not regenerative generation associated with deceleration of the vehicle is currently performed by the alternator 11. In this case, the determination is made according the condition of the driver's accelerator manipulation, the vehicle speed, and the like. If regenerative generation is currently performed, control proceeds to step S12. In step S12, it is determined whether or not the process performed at the present cycle is the one immediately after the start of regenerative generation.
• step S12 control proceeds to step S13 where the residual capacity PbSOC of the lead battery 12 is calculated.
• the method of calculating PbSOC is well known. If briefly explained, PbSOC is calculated from an open-circuit voltage of the lead battery 12 in an open state and an integrated value of current (hereinafter also referred to as current integrated value) of the lead battery 12 in a charging/discharging state.
• step S14 the engine controller 30 sets a turn-on vehicle speed and a turn-off vehicle speed.
• the turn-on vehicle speed is used as a criterion for determining whether to turn on the MOS switch 21 in regenerative generation.
• the turn-off vehicle speed is used as a criterion for determining whether to turn off the MOS switch 21 if it has been turned on in regenerative generation.
• the turn-on vehicle speed corresponds to a vehicle speed threshold (determination value) (connection permission vehicle speed) for determining whether to charge both of the lead battery 12 and the lithium ion battery 13 or to charge only the lead battery 12 during regenerative generation.
• the turn-off vehicle speed corresponds to a vehicle speed threshold (determination value) (connection prohibition vehicle speed) for making a transition from a situation where both of the lead battery 12 and the lithium ion battery 13 are charged during regenerative generation to a situation where only the lead battery 12 is charged.
• a vehicle speed threshold determination value
• connection prohibition vehicle speed connection prohibition vehicle speed
• the turn-on vehicle speed and the turn-off vehicle speed are set based on PbSOC (PbSOC at the start of regenerative generation) calculated in step S13.
• PbSOC PbSOC at the start of regenerative generation
• the turn-on vehicle speed and the turn-off vehicle speed are set based on a relationship shown in Fig. 3.
• Fig. 3 is a diagram illustrating PbSOC relative to turn-on vehicle speed and turn-off vehicle speed. In Fig. 3, the relationship is established such that, the smaller the PbSOC is, the higher the turn-on vehicle speed and turn-off vehicle speed become. In other words, when PbSOC is small, the lead battery 12 is desired to be charged in preference to the lithium ion battery 13.
• the turn-on vehicle speed is set to a higher level so that the MOS switch 21 is hardly turned on. Further, when PbSOC is small, it is desirable that the charge of the lithium ion battery 13 is finished early compared with the case where PbSOC is large. Accordingly, the turn-off vehicle speed is set to a higher level so that the MOS switch 21 is turned off comparatively early.
• the engine controller 30 sets a discharge permission value that is a criterion for determining whether to permit discharge from the lead battery 12 in regenerative generation.
• the discharge permission value corresponds to a threshold (determination value) for determining whether to permit or to immediately stop continuation of discharge of the lead battery 12 in regenerative generation.
• the discharge permission value is set based on the relationship shown in Fig. 4.
• Fig. 4 is a diagram illustrating PbSOC relative to discharge permission value.
• a large discharge permission value here means that a comparatively large amount of discharge is permitted to the lead battery 12 in regenerative generation.
• step S16 it is determined, in step S16, whether or not the vehicle speed of the moment is equal to or higher than the turn-on vehicle speed. If a relation "(Vehicle speed) > (Turn-on vehicle speed)" is satisfied, or if the determination is YES in step S16, control proceeds to step S17 where the MOS switch 21 is turned on. Thus, electrical charge is started to be applied to both of the lead battery 12 and the lithium ion battery 13.
• Pb current current detection value
• the current integrated value corresponds to a difference, i.e. a charge-discharge balance, between an amount of charge of the lead battery 12 in a charging state after the start of regenerative generation, and an amount of discharge of the battery 12 in a discharging state after transition thereto from the charging state.
• the amount of charge is calculated by integrating a Pb charge current in a charging state after the start of regenerative generation, while the amount of discharge is calculated by integrating a Pb discharge current in the following discharging state.
• one current integrated value is calculated through a period of regenerative generation, resultantly calculating a charge-discharge balance.
• the discharge permission value calculated in step S15 corresponds to the "predetermined discharge reference value".
• step S16 if a relation "(Vehicle speed) ⁇ (Turn-on vehicle speed)" is satisfied, or if the determination is NO, the present process is, halted until the next iteration, without turning on the MOS switch 21. Alternatively, if the relation "(Vehicle speed) ⁇ (Turn-on vehicle speed)" is satisfied and thus the MOS switch 21 is not turned on, a current i integrated value may be calculated.
• step S20 it is determined whether or not the current integrated value (absolute value) of the moment has become equal to or more than the discharge permission value.
• This processing is performed for the purpose of determining whether or not an amount of discharge of the lead battery 12 during regenerative generation has exceeded a predetermined amount. Considering that a negative current is integrated in a discharging state of the lead battery 12, this processing is performed for the purpose of determining whether or not the absolute value of the negative current integrated value has become equal to or larger than the discharge permission value.
• step S21 it is determined whether or not the vehicle speed of the moment has become less than the turn-off vehicle speed.
• step S20 If a relation "(Current integrated value) > (Discharge permission value)” or a relation "(Vehicle speed) ⁇ (Turn-off vehicle speed)" is satisfied (if the determination is YES in either step S20 or S21), control proceeds to step S22 where the MOS switch 21 is turned off. Then, the present process is halted until the next iteration.
• regenerative generation is started, triggered by deceleration of the vehicle.
• the vehicle speed is less than the turn-on vehicle speed (e.g., less than 30 km/h).
• the MOS switch 21 is not turned on and thus only the lead battery 12 is charged with regenerative generation.
• the lithium ion battery 13 is prohibited from being charged.
• generated current of the alternator 11 increases. With this increase, electrical charge is started to be applied to the lead battery 12. Accordingly, as shown in Fig. 5, Pb current of the lead battery 12 on a discharge side switches to a charge side.
• regenerative generation is started again, triggered by deceleration of the vehicle.
• the vehicle speed is equal to or more than the turn-on vehicle speed (e.g., 30 km/h or more).
• the MOS switch 21 is turned on.
• both of the lead battery 12 and the lithium ion battery 13 are permitted to be charged.
• the current generated by the alternator 11 increases. With this increase, electrical charge is started to be applied to the lead battery 12 and the lithium ion battery 13.
• the vehicle speed at time t3 is higher and therefore the generated current is larger accordingly.
• the generated current, Pb current and Li current slightly increase or are substantially retained to be constant, but gradually decrease thereafter with the decrease of the vehicle speed.
• Pb current turns from charging current to discharging current.
• the batteries 12 and 13 are mutually electrically connected.
• a relation "(Terminal voltage of the lead battery 12) > (Terminal voltage of the lithium ion battery 13)" is satisfied. Accordingly, the lithium ion battery 13 is preferentially charged.
• the electric power of the lead battery 12 is used for charging the lithium ion battery 13 or for driving electrical loads.
• the lead battery 12 transitions from a charging state to a discharging state.
• a current integrated value is calculated by integrating Pb currents.
• a current integrated value is calculated with the integration of charging currents to gradually increase the current integrated value.
• a current integrated value is calculated with the integration of discharging currents to gradually decrease the current integrated value. Then, at time t5, the current integrated value reaches a predetermined value (discharge permission value) on a negative side, or satisfies a relation "(Integrated value of charging currents) ⁇ (Integrated value of discharging currents + a)" .
• the MOS switch 21 is turned off to stop application of charge to the lithium ion battery 13.
• the period from time t3 to time t5 may be explained in other words as follows. Specifically, in the interval between time t3 and time t4, the engine controller 30 calculates an amount of charge of the lead battery 12 during regenerative generation. Then, in the interval between time t4 and time t5, the engine controller 30 calculates an amount of discharge of the lead battery 12 during regenerative generation. Then, at time t5, the engine controller 30 turns off the MOS switch 21 on the basis of the charge-discharge balance that is the difference between the amount of charge and the amount of discharge.
• the MOS switch 21 is not turned off according to the vehicle-speed condition expressed by a relation "(Vehicle speed) ⁇ (Turn-off vehicle speed)". However, if this vehicle-speed condition is satisfied before the current integrated value reaches the discharge permission value, the MOS switch 21 will be turned off accordingly.
• the discharging state of the lead battery 12 is monitored during regenerative generation, and the MOS switch 21 is electrically disconnected based on the discharging condition. Accordingly, the amount of charge (PbSOC) of the lead battery 12 is prevented from being unintentionally decreased. Thus, electrical charge comes to be efficiently applied to the batteries 12 and 13. This can prevent unintentional decrease of PbSOC during regenerative generation. Also, this can resultantly prevent the alternator 11 from being forced to apply electrical charge to the lead battery 12 in a period other than the period of regenerative generation. Thus, fuel efficiency is hardly impaired in the generation performed by the alternator 11.
• the time point when the batteries 12 and 13 are electrically disconnected from each other during regenerative generation relies on the amount of charge and the amount of discharge to/from the lead battery 12 after the start of regenerative generation. For example, when the amount of charge to the lead battery 12 is comparatively large after the start of regenerative generation, discharge from the lead battery 12 is permitted accordingly.
• the MOS switch 21 is electrically disconnected (brought into an off state) based on the balance between the amount of charge and the amount of discharge to/from the lead battery 12 (current integrated value). Accordingly, the MOS switch 21 can be electrically disconnected at a more appropriate timing.
• a discharge permission value as a discharge reference value is ensured to be set based on the amount of charge (PbSOC) of the lead battery 12 at the start of regenerative generation.
• PbSOC the amount of charge of the lead battery 12
• the MOS switch 21 can be turned off at more appropriate timing.
• the MOS switch 21 is brought into an off state from an on state at a time point when the vehicle speed decreases to the turn-off vehicle speed (connection prohibition vehicle speed) . Accordingly, the engine load caused by the rotation of the alternator 11 is reduced in a predetermined low-speed range. Thus, drivability will not be impaired right before the stop of the vehicle.
• the turn-off vehicle speed is ensured to be high when PbSOC is small at the start of regenerative generation. Accordingly, discharge from the lead battery 12 is reduced during regenerative generation to thereby prevent PbSOC from being decreased. Further, when PbSOC at the start of regenerative generation is large, the turn-off vehicle speed is ensured to be low. Accordingly, the lithium ion battery 13 can be preferentially charged.
• the MOS switch 21 is controlled to be electrically connected, so that both of the batteries 12 and 13 can be charged. Also, when the vehicle speed is equal to or less than the turn-on vehicle speed and thus the amount of generation in regenerative generation is small, only the lead battery 12 is charged. In this case, electrical charge is favorably applied to both of the batteries 12 and 13.
• the timing of turning off the MOS switch 21 can be delayed by setting a low turn-off vehicle speed when LiSOC is small at the start of regenerative generation. Accordingly, the lithium ion battery 13 is preferentially charged during regenerative generation. Further, the timing of turning off the MOS switch 21 can be advanced by setting a high turn-off vehicle speed when LiSOC is large at the start of regenerative generation. Accordingly, discharge from the lead battery 12 is reduced during regenerative generation to thereby prevent decrease of PbSOC.
• the ratio of PbSOC to LiSOC PbSOC/LiSOC) may be calculated. When PbSOC/LiSOC is large, the turn-off vehicle speed may be set to a low level compared with the case where the PbSOC/LiSOC is small.
• a turn-on vehicle speed is set based on not only the amount of charge (PbSOC) of the lead battery 12 at the start of regenerative generation, but also the amount of charge (LiSOC) of the lithium ion battery 13 at the start of regenerative generation.
• PbSOC amount of charge
• LiSOC amount of charge
• a turn-on vehicle speed is set based on PbSOC and LiSOC at every cycle.
• numerical values of +a (comparatively higher vehicle speeds) may be used with respect to the numerical values shown in Fig. 6.
• the lithium ion battery 13 will have more opportunities of being charged, by setting a low turn-on vehicle speed when LiSOC is small at the start of regenerative generation. Further, the lead battery 12 can be preferentially charged during regenerative generation, by setting a high turn-on vehicle speed when LiSOC is large at the start of regenerative generation.
• a discharge permission value is set based on the relationship shown in Fig. 4.
• a discharge permission value may be set to a positive value in any case.
• the larger the PbSOC is at the start of regenerative generation the larger the value may be that is set as the discharge permission value.
• the lead battery 12 is used as the first battery and the lithium ion battery 13 is used as the second battery.
• the second battery may be a different secondary battery, such as a nickel-cadmium battery or a nickel-hydrogen battery.
• the first and second batteries may both be a lead battery, or the first and second batteries may both be a lithium ion battery. In any case, the terminal voltage of the first and second batteries may only have to be different.
• a power system for a vehicle which includes: a generator (11); a first battery (12) and a second battery (13) which are connected in parallel with the generator; land a connection switch (21) which is provided on a connection line (18) electrically connecting the first and second batteries, and which electrically connects and electrically disconnects the first battery and the generator to/from the second battery.
• the power system performs regenerative generation by the generator when the vehicle decelerates.
• a terminal voltage of the first battery is made larger than a terminal voltage of the second battery.
• the connection switch is brought into an electrically connected state to apply electrical charge to both of the first battery and the second battery.
• the first and second batteries have a differently set terminal voltage. Specifically, the terminal voltage of the first battery is set to a higher level than that of the second battery. Accordingly, even during regenerative generation, the state of the first battery may transition from a charging state to a discharging state. For example, in regenerative generation associated with deceleration of the vehicle, the vehicle speed gradually decreases to decrease the amount of regenerative generation performed by the generator. When the amount of regenerative generation decreases in this way, the state of the first battery may transition from a charging state to a discharging state. Thus, the amount of charge (residual capacity) of the first battery may unintentionally decrease during regenerative generation. As a result, the generator can be forced to apply electrical charge to the first battery in a period other than the period of regenerative generation.
• the discharging state of the first battery is monitored during regenerative generation. Based on the discharging state, the connection switch is electrically disconnected. Thus, the amount of charge of the first battery is prevented from being unintentionally decreased. In this way, electrical charge is efficiently applied to the first and second batteries.

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• Engineering & Computer Science (AREA)
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• Transportation (AREA)
• Life Sciences & Earth Sciences (AREA)
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• Sustainable Energy (AREA)
• Charge And Discharge Circuits For Batteries Or The Like (AREA)
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• 2012
  • 2012-08-10 JP JP2012178438A patent/JP5889750B2/ja active Active
• 2013
  • 2013-08-09 WO PCT/JP2013/071986 patent/WO2014025069A1/en active Application Filing
  • 2013-08-09 DE DE112013004005.0T patent/DE112013004005T5/de active Pending
  • 2013-08-09 CN CN201380042071.1A patent/CN104604085B/zh active Active
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