JP2007189797A - Hybrid automobile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device and a method that can easily reduce variations of states of charges (SOC) of battery units during the parking of a vehicle even in a normal parking area and an outdoor parking area, and to provide a control method and a device that can uniformly maintain the states of charges (SOC) of the battery units automatically or by a simple operation of a driver at intervals sufficiently smaller than the interval of the periodic maintenance of the vehicle. <P>SOLUTION: This hybrid automobile is characterized by comprising a circuit constituted such that a plurality of the battery units for the hybrid automobile are set into states of being separated from their loads and a charging power supply, and connected in parallel with one another. The in-vehicle battery units for the hybrid automobile are configured such that, in general, several pieces of the units of the same standards are connected in parallel with one another or in series and used, electrical connection at the use is released once during the stop or the parking of the vehicle, and the battery units are merely mutually connected in parallel with one another while being mounted in the vehicle, and left as they are for an appropriate time (several hours, for example). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention is used for a hybrid vehicle using both internal combustion engine power and electric power. The present invention relates to an apparatus and method for satisfactorily maintaining the state of a battery mounted on a hybrid vehicle and serving as an electric power supply source for a long period of time. The present invention provides a state in which a plurality of battery units are connected in parallel or in series as a high-voltage DC power source for a hybrid vehicle, and the state of charge (SOC) of the battery units is made uniform. Related to control.

  A hybrid vehicle is provided with an electric motor in addition to an internal combustion engine as an engine for supplying driving power, and a driving current is supplied to the electric motor from an on-vehicle battery, and driving auxiliary power is generated from the electric motor to an axle. When such a hybrid vehicle decelerates in the running state, it is controlled so that the generator acts by the rotational power of the axle to be in a braking state, and the electric energy generated by the generator is charged and regenerated in the vehicle battery. It is configured. The hybrid vehicle manufactured and sold by the applicant of the present application adopts a configuration in which the motor and the generator are configured as a “motor generator” which is a single hardware rotating machine and used as a motor or a generator according to the operation mode. is doing.

  Thus, in a hybrid vehicle equipped with a motor generator, the motor generator is set to a motor mode when the vehicle is accelerating, and electric energy is supplied to the motor generator from an in-vehicle battery, and the generated rotational power is converted into an axle. Is supplied as driving power. On the other hand, when the vehicle is in a braking state, the motor generator is switched to the generator mode, and the electric energy generated by the motor generator is charged and regenerated in a vehicle-mounted battery. The battery for this purpose is extremely large compared to a battery mounted on a normal automobile.

  Here, the “battery unit” is a mounting form of a high-voltage battery mounted on a hybrid vehicle. For example, the battery unit can be repeatedly charged and discharged with a terminal voltage of about 200 V and a maximum charge amount of about 100 Ah, and has a configuration in which a large number (several hundreds) of cells are connected in series for safety of handling. An open / close relay is provided at the input / output terminal. A battery is a form in which cells constituting the battery are connected in series, and together with the open / close relay, the battery is formed as a whole in a mechanically inseparable unit, and in general, its internal connection cannot be accessed over the entire lifetime. If the internal connection is disconnected, it is impossible to recover in principle and it will be destroyed. According to the rated voltage and rated current of the electric power device of the hybrid vehicle, a plurality (m) of the battery units are connected in parallel, a plurality (p) of the battery units are connected in series, or a plurality (m ) A plurality (p) of the configurations connected in parallel are connected in series and mounted in a hybrid vehicle, which becomes a DC power supply for power of the hybrid vehicle. This battery unit is mounted on a hybrid vehicle and is used to supply electric energy for driving the vehicle or to store electric energy generated by braking the vehicle. This battery is a low-voltage battery (eg, 12V, 24V, etc.) that supplies direct current to vehicle lighting fixtures, internal combustion engine control circuits, radio receivers, internal combustion engine starter motors, and other general electrical components. It is a battery provided separately.

Japanese Patent No. 3411735 JP2000-261977

  In order to obtain various rated values (eg, several hundred volts, several hundred ampere hours) such as terminal voltage and charging capacity in a practical form, the large-scale battery power supply of a hybrid vehicle uses the standardized battery unit. It is configured by using a combination, that is, by connecting battery units in series or in parallel. When designed to obtain the required high rated voltage or large rated current by connecting a plurality of battery units in series or in parallel, the characteristics (for example, internal resistance, temperature characteristics, etc.) of each battery unit are not necessarily uniform. As a result, a phenomenon occurs in which the amount of charge or the state of charge (referred to as “State of Charge” or “SOC”) held by each battery unit varies while charging and discharging accompanying the traveling of the vehicle are repeated. This variation in the state of charge has the property that, in principle, the charge state is not converged but rather enlarged as charge and discharge are repeated according to the road running state of a normal vehicle. This is unavoidable that even if a unit battery having a small variation in characteristics is combined, the variation will increase due to long-term use. To recover this, disconnect the connection between multiple unit batteries, connect them individually or in parallel, and supply a charging current for a long time (eg, 10 hours) with a small current from the outside. Maintenance work is required.

  Conventionally, this maintenance work is performed while the operation of the vehicle is stopped. In addition, in order to perform this maintenance work, a charging facility for each in-vehicle battery is required in the parking lot or garage of the vehicle. This charging facility becomes large-scale, and it is impossible to frequently do this for many vehicles in a general garage or outdoor parking lot. Moreover, since the terminal voltage of the battery unit mounted on the hybrid vehicle is high, a general driver cannot perform an operation for easily changing these electrical connections.

  The present invention relates to a state of charge (SOC) of each battery unit in a power supply device for a hybrid vehicle that is specified by mounting a plurality of battery units on one vehicle and connecting the plurality of battery units in series or in parallel. The purpose of this is to control the occurrence of variation in a small amount. The present invention provides a variation in the state of charge (SOC) between battery units in a place where there is no predetermined charging facility for an in-vehicle battery for a hybrid vehicle, that is, in a normal parking lot or an outdoor parking lot, while the vehicle is parked. It is an object of the present invention to provide an apparatus and a method capable of reducing the size of the apparatus. An object of the present invention is to provide a method and an apparatus for equalizing a state of charge (SOC) of a battery unit by an operation mode that can be safely executed by a general driver. It is an object of the present invention to provide a method and an apparatus that can extend the cycle of battery maintenance by supplying a charging current from an external charging device for an on-vehicle battery for a hybrid vehicle. The present invention provides a control method and apparatus in which a state of charge (SOC) of a battery unit is uniformly maintained by a simple operation of a driver or automatically at an interval sufficiently smaller than a regular vehicle maintenance interval. The purpose is to do. An object of the present invention is to maintain the state of charge (SOC) of a battery unit uniformly over a long period of time and to substantially extend the life of the battery. An object of the present invention is to provide a safe method and apparatus in which a driver or an operator does not have to directly touch a high-pressure device of a vehicle.

  The present invention sets a plurality of battery units for a hybrid vehicle in a state where they are disconnected from their load and charging power source when the vehicle is not operated for a long time, such as at night, and is simply connected in parallel to each other. It is characterized by providing a circuit to be kept. An in-vehicle battery unit for a hybrid vehicle is generally used in such a manner that several devices of the same standard are connected in parallel or in series for one vehicle, and the present invention is used when the vehicle is stopped or parked. This is a method of releasing the general connection form, simply connecting the battery units in parallel with each other while the battery units are mounted on the vehicle, and leaving them for a suitable time (eg, several hours). It is a device that realizes.

  In general, in a battery unit of the same standard, a battery unit with a small charge amount has a terminal voltage lower than a terminal voltage of a battery unit with a large charge amount. The electric characteristics (mainly internal resistance value) become uniform. The time for connecting the battery units in parallel is several hours. Illustrative examples are 2 hours, 5 hours, 10 hours, and the like. The parallel connection can be canceled by a timer relay, when the current is monitored and it is below a predetermined value, or by an artificial operation. In the present invention, it is preferable to set the parallel connection in a state where the engine key of the vehicle is operated off.

  In other words, the first aspect of the present invention is a method invention, in which a plurality of battery units having the same rated voltage mounted on the vehicle are mounted on the vehicle while the operation of the vehicle is stopped, and substantially charged against the load. It is characterized in that the state of charge (SOC) of the plurality of high-voltage battery units is made uniform by electrically connecting them in parallel over an appropriate long time (eg, several hours) in the absence of a discharge current.

  The second of the present invention is an apparatus invention, wherein a plurality of n unit cells of the same standard that can be charged / discharged are connected in series, and open / close relays (2a, 2b, 2c, 2d, 3a, 3b, 3c, 3d, respectively) at both ends thereof. ) Are connected to a plurality of m battery units (1a, 1b, 1c, 1d), and the plurality of m battery units are connected to the switching relays (2a, 2b, 2c, 2d, 3a, 3b, 3c, A DC power supply device (10) configured to be connected in parallel (or in series) via the contacts of 3d), and a control circuit (6) for supplying a drive current to the drive windings of the open / close relay according to the control, respectively In the hybrid vehicle provided with the terminal, the terminals (4, 5) of the DC power supply (10) are substantially connected to the electric circuit of the vehicle (when the key switch 7 is in the OFF state) while the vehicle is not operating. Load and A circuit means for supplying a driving current to the driving winding of the open / close relay and connecting the m battery units in parallel while being disconnected from the power source is provided.

  The plurality of m battery units are further connected in series with a plurality of p pieces (eg, two, three), and the control circuit is connected to the drive winding of the switching relay of the plurality of p battery units connected in series. In addition, as a configuration in which a driving current is supplied and a means for connecting a plurality of m × p batteries in parallel for every m batteries is provided, a battery having a larger scale can be implemented. A timer circuit that automatically cancels the parallel connection state may be provided.

  The method of the present invention is preferably executed as regularly as possible with respect to travel time, and the vehicle is equipped with a travel distance accumulator or travel time accumulative display meter that is automatically reset each time the operation of the present invention is performed. Can keep

  With the method or apparatus of the present invention, the charge amount of each battery unit is automatically made uniform for a plurality of battery units of the same standard. The operation for carrying out the present invention merely switches the connection path of the battery terminal while the vehicle is stopped, and does not require a special device such as a charging device or a large additional device. When one driver finishes his / her duty, it can be carried out without the assistance of another person. The method of the present invention can be carried out at any time in an outdoor garage or parking lot. By implementing the present invention, it is possible to lengthen the period of maintenance work such as recharging of the battery unit. Further, by implementing the present invention, the plurality of battery units are not operated for a long time with the charge states being uneven, and some battery units are not consumed unevenly. Thereby, the whole battery life can be lengthened. Even if the timing for releasing the parallel connection according to the present invention is lost, there is almost no actual harm, and the battery is not damaged by carrying out the present invention.

  First, an example of the overall configuration of a hybrid vehicle that implements the present invention will be described with reference to FIG. The main internal combustion engine 100 for power of the vehicle is a diesel engine, and a motor generator 200 is fixedly connected to an output shaft thereof. The motor generator is configured such that a rotor winding is attached around its rotation axis, and this rotates around the mechanical center of a fixed field winding provided around the motor generator. This device is an AC induction rotating machine, and the rotor winding is constrained in the rotor and there is no lead wire outside. A clutch 300 is provided on the output rotation shaft (right side in the figure) of the motor generator 200. The clutch 300 may be either one that is opened and closed by a driver's clutch pedal (not shown) or one that is automatically opened and closed according to rotation. A transmission 400 is provided on the output shaft of the clutch 300. The output shaft of the transmission 400 is connected to a propeller shaft (not shown), and the propeller shaft is configured to drive the axle. The structure of the clutch 300, the structure of the transmission 400, the structure of the rotating shaft from the propeller shaft to the axle, and the like are well-known structures of automobiles, and are not directly related to the characteristics of the present invention, and thus are more detailed. Description is omitted.

  A three-phase alternating current is supplied from the inverter 21 to the stator winding of the motor generator 200, and a rotating magnetic field is generated around the rotor shaft of the motor generator 200. The frequency of the three-phase alternating current, that is, the rotational speed of the rotating magnetic field is controlled according to the output rotational speed of the rotation sensor 25 provided in the internal combustion engine 100 and the control signal generated by the program control circuit 23. The program control circuit 23 is connected to the accelerator pedal operated by the driver, information on the gear ratio set in the transmission 400, and a brake pedal operation signal operated by the driver via the interface circuit 24. Then, clutch operation information, vehicle speed information, other vehicle state information and driving operation information are taken in, and control signals generated by the inverter control circuit 22 are controlled. The inverter control circuit 22 controls the rotational phase speed of the inverter 21 according to the logic set based on the input information.

  For example, when the low gear is set in the transmission 400 and the accelerator pedal is depressed, the driver is instructing acceleration of the vehicle, and the motor generator 200 is used as an electric motor so that the internal combustion engine 100 is auxiliary accelerated. To work. This controls the rotational speed of the rotating magnetic field to be greater than the physical rotational speed of the armature. When the vehicle speed sensor 27 outputs a corresponding vehicle speed and the accelerator pedal is released, it is assumed that the driver is decelerating the vehicle, and the motor generator 200 is used as the generator. Is controlled so as to perform auxiliary braking. This is performed by controlling the rotational speed of the rotating magnetic field to be smaller than the physical rotational speed of the armature. At this time, the detector 26 detects the charge amount information of the DC power supply (high voltage battery) and sends it to the inverter control circuit 22. That is, when the charge amount of the battery is small, the charge current of the high voltage battery is increased, and when the charge amount of the battery is already large and there is no charge margin, the charge current is controlled to be small. The DC-DC converter 28 is provided to generate a general power supply current of DC 24V that uses the high voltage generated by the DC power supply device 10 in the vehicle.

  Here, the feature of the present invention resides in the control of the DC power supply device 10 constituted by a high-voltage battery. In particular, it is not the time when the vehicle is running, but the control of the DC power supply 10 when the vehicle is stopped, the driver removes the engine key, and is left parked or parked for a corresponding long time. A circuit 20 indicated by a chain line is a DC power supply control circuit according to the present invention. The battery 8 is a low-voltage battery that is supplied to general electrical components of the vehicle. Hereinafter, the DC power supply control circuit 20 according to the present invention will be described in detail.

(First Example)
FIG. 1 is an electric circuit diagram of the apparatus according to the first embodiment of the present invention. The high voltage battery units 1a and 1b are hybrid high voltage battery units mounted on a vehicle. This is one element of the DC power supply device 10 described above. For example, the rated terminal voltages of the high voltage battery units 1a and 1b are 200V. These are devices in which a large number of n cells are connected in series, but in a practical form mounted on a vehicle, the internal cells are set to a structure that is substantially physically inseparable. Inside the high voltage battery units 1a and 1b, open / close relays 2a, 2b, 3a, 3b are mounted in a single strong plastic box integrally with the battery. As indicated by broken lines, in the first embodiment, two high voltage battery units 1a and 1b are mounted as one DC power supply device 10 and mounted on the vehicle. Only terminals 4 and 5 appear outside, and these two terminals are protected from human touch. These terminals 4 and 5 are the terminals 4 and 5 in FIG.

  This vehicle is equipped with a control circuit 6 for controlling the open / close relays 2a, 2b, 3a, 3b. The control circuit 6 is a relatively simple program control circuit, which is an existing device regardless of the present invention. The control circuit 6 is supplied with an operating current from a low-voltage battery (12 V) of the vehicle via a vehicle key switch 7 as a power source for the operation. The key switch 7 is operated by the driver and is turned on when starting the internal combustion engine of the vehicle, and turned off when stopping the rotation of the internal combustion engine. When the key switch 7 is operated by the driver to be in the “on” state, the control circuit 6 is activated to turn on the open / close relays 2a, 2b, 3a, 3b, and the terminals of the two high-voltage battery units 1a and 1b. A voltage appears between the pair of terminals 4 and 5 in parallel. The pair of terminals 4 and 5 is connected to the DC terminal of the inverter 21 described in FIG. 3, and the motor generator 200 is connected to the AC terminal of the inverter 21.

  Here, the feature of the present invention is that the hybrid vehicle has ended operation, the key switch 7 is turned off by the driver, and the internal combustion engine of the vehicle has also stopped rotating and is in a paused state. Sometimes it is. In other words, the positive potential of the low-voltage battery 8 is not affected by the operation of the key switch 7 (or in a state in which the key switch 7 is turned off). Connected to the wire. The positive potential of the low-voltage battery 8 is supplied to the switching relays 2a, 2b, 3a via the contact of the relay 16, further via the contact of the timer relay 15, and further via the backflow prevention diodes 11a, 11b, 12a, 12b. , 3b.

  In such a configuration, when the start switch 14 is operated by the driver, the relay 16 is activated, and the open / close relays 2a, 2b, 3a, 3b are driven via the backflow prevention diodes 11a, 11b, 12a, 12b. The positive and negative ends of the high voltage battery unit 1a are respectively connected to the positive and negative ends of the high voltage battery unit 1b. The battery units 1a and 1b are devices having the same rated voltage. Generally, even when devices having the same rated voltage are connected in parallel to each other, no current flows through the connection passage. However, at this time, if a small charge amount difference is generated between the high voltage battery unit 1a and the high voltage battery unit 1b, a small potential difference is generated in the terminal voltage. A slight current will flow through. That is, the two high-voltage battery units 1a and 1b have no potential difference between the terminals due to their specifications, and if there is a potential difference, it is inherently slight, which is caused by non-uniform charge amounts. . The state of the parallel connection of the two high voltage battery units 1a and 1b is maintained for several hours (eg, 2 hours to 10 hours), and the timer relay 15 releases the connection.

  With such a configuration, next, for example, when starting operation of the vehicle the next morning, the terminal voltages of the two high-voltage battery units 1a and 1b, that is, the charge capacities, are considered to be averaged. It is possible to avoid further running of the day while the charge capacity of the high-voltage battery unit is not uniform. The circuit components added by the present invention having such a configuration are only the relay circuit 13 and the backflow prevention diodes 11a, 11b, 12a, and 12b.

(Second embodiment)
FIG. 2 is an electric circuit diagram of the apparatus according to the second embodiment of the present invention. This is of a specification that is mounted on a larger vehicle than the first embodiment device, in which two battery units 1a and 1b are connected in parallel, and two battery units 1c and 1d are connected in parallel. Connected in series and used. This doubles the voltage available from terminals 4 and 5 and doubles its current capacity. This configuration is implemented in large cargo vehicles.

  The present invention can be similarly implemented for such a configuration. That is, the relays 2a, 2b, 3a, 3b, 2c, 2d, 3c, and 3d provided at the input and output of the four battery units 1a, 1b, 1c, and 1d, respectively, without the control circuit 6 being relayed. The circuit 13 is configured to send a driving current for driving each relay winding. That is, when the operation of the vehicle equipped with this device is completed, the key switch 7 is turned off, and then the start switch 14 is turned on by the driver so that the relay 16 and the timer relay 15 are enabled. become. As a result, the battery units 1a and 1b and 1c and 1d are connected in parallel, and a smaller current flows in a slight potential difference generated between the battery units, so that the charge amount between the battery units is reduced. This can be averaged when non-uniform conditions occur.

  The present invention can be implemented by providing a few additional circuits in each vehicle. In order to carry out the present invention, it is not necessary to provide a new facility in a parking lot or a factory. Therefore, a small-scale transportation company having a small number of hybrid vehicles or an owner of a personal hybrid vehicle can implement the present invention. Can be implemented. By implementing the present invention, the battery life of the vehicle is substantially increased, and the battery maintenance cycle can be extended. The method or apparatus of the present invention can be safely implemented without the need for the operator to touch the high voltage circuit directly to do this.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 3 is a circuit diagram of an apparatus according to a second embodiment of the present invention. 1 is an overall circuit configuration diagram of a hybrid vehicle embodying the present invention.

Explanation of symbols

1a, 1b, 1c, 1d Battery unit 2a, 2b, 2c, 2d Open / close relay 3a, 3b, 3c, 3d Open / close relay 4 terminal 5 terminal 6 Control circuit 7 Key switch 8 Low voltage battery 10 DC power supply 11 Reverse current prevention diode 12 Reverse current Prevention diode 13 Relay circuit 14 Start switch 15 Timer relay 16 Relay 17 Switch 20 DC power supply control circuit 21 of the present invention Inverter 22 Inverter control circuit 23 Program control circuit 24 Interface circuit 25 Rotation sensor 26 Detector 27 Vehicle speed sensor 28 DC-DC Converter 29 Detection circuit 100 Internal combustion engine 200 Motor generator 300 Clutch 400 Transmission

Claims (4)

  While a vehicle is not in operation, the battery is mounted on the vehicle with a plurality of battery units with the same rated voltage, and there is substantially no charge / discharge current for the load. A method for maintaining a hybrid vehicle battery in which the state of charge (SOC) of the plurality of high-voltage battery units is made uniform by connecting them in parallel. A plurality of n unit cells of the same standard that can be charged / discharged are connected in series, and a plurality of m battery units each having contact points of open / close relays connected to both ends thereof are provided.
A DC power supply device configured by connecting the plurality of m battery units in parallel or in series via the contacts of the switching relay, and a control circuit for supplying a driving current to the driving windings of the switching relay according to each control In a hybrid car with
In the state where the terminal of the DC power supply device is substantially disconnected from the electric circuit of the vehicle during the suspension of the operation of the vehicle, a driving current is supplied to the driving winding of the open / close relay to connect the m battery units in parallel. A hybrid vehicle characterized in that it is provided with circuit means for connection to the vehicle.   The plurality of m battery units are further connected in series with a plurality of p pieces (eg, two, three), and the control circuit is connected to the drive winding of the switching relay of the plurality of p battery units connected in series. The hybrid vehicle according to claim 2, further comprising means for supplying a driving current and connecting a plurality of m × p batteries in parallel in units of m.   4. The hybrid vehicle according to claim 2, further comprising a timer circuit that automatically cancels the means for connecting in parallel.

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