JP2013163434A - Control device of hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of a hybrid vehicle that can protect onboard electric equipment from overvoltage by preventing overvoltage by regenerative electric power in the reverse gear shift operation during traveling.SOLUTION: A control device of a hybrid vehicle includes: a reverse gear shift determination means 47 to determine whether it is a reverse gear shift state in which a shift position is in a reverse gear position corresponding to a reverse direction to a vehicle travel direction; a torque command value selection means 44 to select a torque command value of a smaller one in an absolute value among a regenerative torque command value calculated based on electric power acceptable by a battery as regenerative power and an accelerator torque command value decided according to an accelerator quantity; and a reverse gear shift time torque command value output means 48 to output a torque command value selected by the torque command value selection means 44 to an electric motor when the state is determined as the reverse gear shift state by the reverse gear shift determination means 47.

Description

  The present invention relates to a hybrid vehicle control device, and more particularly to a hybrid vehicle control device capable of recovering regenerative power.

  A hybrid vehicle is configured to travel by operating a plurality of power sources simultaneously or individually when traveling. For example, in a series hybrid system vehicle, when driving (powering), the wheel is driven by operating the electric motor with the electric power supplied from the generator driven by the engine and / or the electric power from the battery. Is configured to do. On the other hand, at the time of regeneration, in the hybrid vehicle, the electric motor functions as a generator, and regenerative power can be supplied to the battery.

  Further, in some vehicles of the hybrid vehicle, the gear shift position is changed from the forward position (D position) to the reverse position (R position) or from the R position without stopping the vehicle while the vehicle is running. The position can be switched (for example, refer to Patent Document 1). In particular, a tracked vehicle having a crawler track or a caterpillar can be configured to perform a shift operation from a shift position corresponding to the traveling direction to a shift position corresponding to the reverse direction without stopping the vehicle as described above. Workability and mobility according to the purpose of the tracked vehicle are achieved. Examples of tracked vehicles include special vehicles, construction machines such as bulldozers, power shovels, and cranes, and transport vehicles.

  For example, in the vehicle of Patent Document 1, when the shift position is switched from the D position to the R position during forward travel, regenerative braking is performed by the electric motor until the vehicle speed becomes a predetermined value or less. Thereby, in the vehicle of patent document 1, while ensuring brake torque or deceleration torque, regenerative electric power can be obtained.

JP 2009-51366 A

  However, for example, when the driver performs a shift operation from the D position to the R position while stepping on the accelerator during forward travel, the vehicle is required to switch quickly from forward travel to reverse travel. During the forward / reverse switching, the electric motor operates from power running at the D position to power running at the R position through regeneration at the R position. For this reason, sudden switching of the power direction occurs in the power system. At this time, when the battery cannot absorb the regenerative power of the motor, the voltage of the DC bus to which the battery is connected rises excessively, and this overvoltage causes the electrical equipment connected to the DC bus to fail or the electrical equipment against the overvoltage There is a risk of stopping the vehicle due to the protection operation.

  For example, in the vehicle of Patent Document 1, when a shift operation is performed from the shift position corresponding to the current forward / backward traveling direction to the shift position corresponding to the reverse direction, the electric motor generates regenerative power regardless of the state of the battery. As a result, a failure of the electrical device or a vehicle stop occurs.

  As a measure for solving this problem, it is conceivable to operate the battery at a low state of charge (SOC) during vehicle operation so that the regenerative power can be recovered with a margin. However, if the SOC is operated in a low state, there is an inconvenience that the battery power that can be used during traveling decreases. Further, as another countermeasure, it is conceivable to increase the battery capacity. However, there is a problem that a battery having a sufficient battery capacity cannot be mounted due to cost and in-vehicle (size) restrictions.

  The present invention has been made to solve such a problem, and prevents overvoltage caused by regenerative power when the shift position is switched in the direction opposite to the traveling direction during traveling, and overvoltages the electrical equipment. It aims at providing the control apparatus of the hybrid vehicle which can be protected from.

  In order to solve the above-described problems, the present invention provides an engine, a generator driven by the engine, a battery, and driving power based on a torque command value, and provides regenerative power to the outside. A control apparatus for a hybrid vehicle, comprising: an electric motor that can be provided to the battery; and determining whether or not the shift position is a reverse shift state at a reverse shift position corresponding to a direction opposite to the vehicle traveling direction. Of the reverse shift determining means, the regenerative torque command value calculated based on the power that the battery can accept as regenerative power, and the accelerator torque command value in the reverse direction determined according to the accelerator amount, the absolute value of Torque command value selection means for selecting the smaller torque command value and the torque command value selection means when the reverse shift determination means determines that the reverse shift state is established. Is characterized by comprising a reverse shifting time torque command value output means for outputting the selected torque command value to the electric motor, the.

  In the hybrid vehicle control device of the present invention configured as described above, the shift lever is switched to the shift position corresponding to the reverse direction with respect to the vehicle traveling direction, and the vehicle traveling direction and the shift position are inconsistent. ), The regenerative torque command value calculated based on the rechargeable power that the battery can accept as regenerative power, and the torque command with the smaller absolute value among the accelerator torque command values determined according to the accelerator amount It is comprised so that an electric motor may be operated according to a value.

  With this configuration, in the present invention, the regenerative power that the motor regenerates to the battery via the DC bus can be limited to the power that the battery can accept as regenerative power regardless of the accelerator amount. As a result, in the present invention, at the time of reverse gear shifting, the regenerative power is suppressed to less than the power that can be absorbed by the battery. Therefore, the DC bus becomes overvoltage, and the electrical equipment connected to the DC bus fails due to the overvoltage. Can be prevented.

Preferably, in the present invention, the torque command value selection means includes regenerative torque command value calculation means, and the regenerative torque command value calculation means generates rechargeable power that the battery can accept based on the SOC of the battery. The regenerative torque command value is calculated so that the rechargeable power is regenerated by the electric motor.
In the present invention configured as described above, the regenerative torque command value is calculated based on the state of the battery, that is, the SOC (charge rate) of the battery. Can be reliably prevented from becoming overvoltage.

  Specifically, the regenerative torque command value calculation means calculates a regenerative torque command value based on a value obtained by dividing chargeable power by the rotation speed of the electric motor.

  In the present invention, it is preferable that the control unit further includes a mechanical brake command value output unit, and the mechanical brake command value output unit has a predetermined deceleration torque regardless of the operation amount of the brake pedal in the reverse shift state. Therefore, the brake command is output to a mechanical brake device that directly or indirectly brakes the electric motor.

For example, if the driver performs a reverse gearshift operation while the vehicle is traveling at a relatively high speed, if sufficient braking torque is obtained only by regenerative torque, the regenerative power becomes too large, and an overvoltage of the DC bus causes an electrical device failure. Risk increases.
However, in the present invention, the shortage of the deceleration torque is compensated by the mechanical brake. Thus, according to the present invention, it is possible to prevent the electric device from being damaged due to the overvoltage of the DC bus caused by the regenerative power, and at least a predetermined deceleration torque can be secured.

Preferably, in the present invention, the mechanical brake command value output means calculates a brake command so as to compensate for a difference between the accelerator torque command value and the selected torque command value.
In the present invention configured as described above, even when the deceleration torque corresponding to the operation amount (accelerator amount) of the accelerator pedal operated by the driver cannot be obtained only by the regenerative torque, the insufficient deceleration torque is mechanically reduced. It can be compensated by braking by the brake device. As a result, in the present invention, a sufficient deceleration torque can be obtained at the time of reverse shifting, and the driver can drive without an uncomfortable feeling between the accelerator amount and the deceleration torque obtained thereby.

  Specifically, the torque command value selection means includes an accelerator torque command value calculation means, and the accelerator torque command value calculation means calculates an accelerator torque command value from a torque command value table associated with the accelerator amount. To do.

Preferably, in the present invention, the torque command value selection means includes vehicle speed torque command value calculation means, and the vehicle speed torque command value calculation means calculates a vehicle speed torque command value in the reverse direction according to the vehicle speed, The command value selection means selects the smallest torque command value from the three torque command values including the regenerative torque command value, the accelerator torque command value, and the vehicle speed torque command value.
In the present invention configured as described above, since the torque command value can be limited according to the vehicle speed, excessive regenerative power is generated in the reverse shift state during high-speed traveling, and the electric device breaks down due to overvoltage. This can be suppressed.

Preferably, in the present invention, the vehicle speed torque command value calculation means calculates a vehicle speed torque command value so that a value obtained by multiplying the vehicle speed torque command value by the vehicle speed becomes a constant value, and the constant value is preset.
In the present invention configured as described above, since the regenerative power can be limited to a constant value regardless of the vehicle speed, it is possible to reliably prevent an overvoltage of the DC bus.

  According to the hybrid vehicle control device of the present invention, when the shift position is switched in the direction opposite to the traveling direction during traveling, it is possible to prevent overvoltage due to regenerative power and protect the in-vehicle electric device from overvoltage. .

1 is an overall configuration diagram of a hybrid vehicle in an embodiment of the present invention. It is explanatory drawing of the motor torque control of the control apparatus in embodiment of this invention. It is explanatory drawing of the torque correction value calculation process for steering in embodiment of this invention. It is explanatory drawing of the electric power control of the control apparatus in embodiment of this invention. It is explanatory drawing of the torque correction value calculation process at the time of reverse gear shift of the control apparatus in embodiment of this invention. It is explanatory drawing of the torque correction value calculation process at the time of reverse gear shift of the control apparatus in the 2nd Embodiment of this invention.

Next, a control apparatus for a hybrid vehicle according to an embodiment of the present invention will be described with reference to FIGS.
First, based on FIG. 1, the structure of the power part of a hybrid vehicle is demonstrated in relation to the hybrid vehicle control apparatus of this embodiment. In the present embodiment, a tracked vehicle (for example, a special vehicle, a construction machine such as a bulldozer, a power shovel, and a crane and a transport vehicle) will be described as an example of a hybrid vehicle. It may be a vehicle.

  As shown in FIG. 1, the hybrid vehicle 100 of this embodiment includes an engine 1, a generator 2, a converter 3, a battery 4, a DC bus 5, a left inverter 6 for traveling, and a traveling vehicle. A right inverter 7, a left permanent magnet synchronous motor 8 for traveling, a right permanent magnet synchronous motor 9 for traveling, a left crawler belt 10, a right crawler belt 11, and a control device 12 are provided. ing.

  The generator 2 is configured to be driven by the engine 1 to generate AC power. The generator 2 is connected to the DC bus 5 via the converter 3 and supplies the generated power to the DC bus.

  The converter 3 is attached to the generator 2, controls the torque of the generator 2 based on the generator torque command value Tg *, converts the AC power generated by the generator 2 into DC, and converts the DC bus 5 Output to. Converter 3 is configured to control charging / discharging of power by battery 4 by controlling the bus voltage of DC bus 5.

The battery 4 is a chargeable / dischargeable secondary battery, and supplies (discharges) DC power to the DC bus 5 according to the voltage of the DC bus 5, or receives DC power from the DC bus 5 and charges it. It is like that.
In the present embodiment, the battery 4 does not have a power conversion device (DC / DC converter) that controls battery power, and is directly connected to the DC bus 5. In the present embodiment, the fuel consumption and in-vehicle performance of the vehicle 100 are improved by adopting a configuration that does not use a power conversion device for battery power control.

The control device 12 is configured to control the engine 1, the generator 2, the converter 3, the inverters 6 and 7, the electric motors 8 and 9, and the like.
The control device 12 is connected to an accelerator pedal 20, a brake pedal 21, a shift lever 22, a steering 23, and a crawler speedometer (or vehicle speed watch) 24, and determines an accelerator amount that is an operation amount of the accelerator pedal 20 operated by a driver. A signal indicating a brake amount that is an operation amount of the brake pedal 21, a signal indicating a shift lever position from the shift lever 22, a signal indicating a steering amount that is an operation amount of the steering 23, and the tracks 10 and 11 from the track speedometer 24. A signal representing each track speed or vehicle speed is received. Based on these signals, the control device 12 converts the inverter torque command values (or motor torque command values) E _L and E _R for operating the motors 8 and 9 through the inverters 6 and 7 to the inverters 6 and 7. 7 is output.

Each inverter 6, 7 controls the torque of the corresponding electric motor 8, 9 based on the electric motor torque command values E _L , E _R received from the control device 12. Specifically, the inverters 6 and 7 convert the DC power of the DC bus 5 fed from the generator 2 and / or the battery 4 into AC power, and supply the AC power to the corresponding motors 8 and 9. , 9 are driven. The rotation output shafts of the electric motors 8 and 9 are connected to the crawler belts 10 and 11 directly or indirectly, respectively, and the electric motors 8 and 9 are configured to provide the crawler belts 10 and 11 with traveling power to drive the vehicle 100. It is configured.

  The electric motors 8 and 9 are driven electrically independently, and the vehicle 100 can be accelerated and decelerated and turned by the power running and regeneration of the two electric motors 8 and 9. Regenerative power generated by the regenerative operation of the electric motors 8 and 9 as the synchronous generator is converted into direct current by the inverters 6 and 7 functioning as a converter and supplied to the direct current bus 5. The regenerative electric power of each electric motor 8, 9 is absorbed by the battery 4 via the DC bus 5, or is used to drive the other electric motor via the DC bus 5, the other inverter.

  The crawler belts 10 and 11 or the electric motors 8 and 9 are directly or indirectly connected to a braking brake or a mechanical (mechanical) brake (not shown) that generates a deceleration torque. The braking brake is configured to generate a braking torque on the basis of a mechanical (mechanical) brake command determined according to a brake amount that is an operation amount of the brake pedal 21.

Next, based on FIG.2 and FIG.3, the outline of the output torque control of an electric motor is demonstrated.
In normal acceleration / deceleration and turning operations, the control device 12 performs the forward / reverse torque command values A _L and A _R determined from the accelerator amount, the brake amount, and the shift position, the steering amount, the target speed of the crawler track, The inverter torque command values E _L and E _R for controlling the output torque of the motor are output using the steering torque correction values D _L and D _R calculated based on the actual speed and the like. (See FIG. 2).

Further, in the operation at the time of reverse shifting, the control device 12 uses the reverse conversion torque command values C _L and C _R determined based on the SOC, the accelerator amount, etc. of the battery 4 as the forward / reverse torque command values A _L , Instead of A _R , forward / reverse torque command values B _L and B _R are output (see FIG. 5).

  FIG. 2 shows a block diagram of the control device 12 relating to the output torque control of the electric motors 8 and 9. As shown in FIG. 2, the control device 12 relates to the output torque control of the electric motors 8 and 9, the forward / reverse torque command value calculation device 30, the reverse transmission torque correction value calculation device 40, and the steering torque correction. A value calculation device 50 is provided.

The forward / reverse torque command value calculation device 30 calculates the forward / reverse torque command values A _L and A _R for the left and right motors 8 and 9, respectively, based on the accelerator amount, the brake amount, and the shift position, and reverse shift torque. The correction value is output to the correction value calculation device 40.
The forward / reverse torque command value calculation device 30 has a table in which a torque command value is associated with each accelerator amount for each shift position, and is configured to calculate a torque command value in consideration of the brake amount. ing.

The reverse shift torque correction value calculation device 40 is configured so long as the driver does not switch the shift lever to a shift position corresponding to the direction opposite to the traveling direction during traveling of the vehicle (that is, when the traveling direction matches the shift position). The received forward / reverse torque command values A _L and A _R are directly output as the forward / reverse torque command values B _L and B _R.

However, when the driver switches the shift lever to a shift position corresponding to the direction opposite to the traveling direction during traveling of the vehicle (that is, during reverse shifting where the traveling direction and the shift position do not match), the vehicle 100 is Travels in the opposite direction to the travel direction indicated by. In the reverse travel times, the reverse shift torque correction value calculation unit 40, the reverse torque command value B _L before outputting to the left and right of the inverter 6, a B _R, as will be described later, forward and reverse torque command value A Switching from _L , A _R to reverse shift torque command values C _L , C _R (see FIG. 5).

Also, the steering torque correction value calculation unit 50, the steering amount, based on the vehicle speed, the forward-reverse torque command value B _L, for correcting the B _R, steering torque correction value D _L, the D _R calculate. The adder, the steering torque correction value D _L, D _R are added before the reverse torque command value B _L, the B _R, respectively, forward and reverse torque command value B _L, B _R is the motor torque command value ( Or, the inverter torque command value is corrected to E _L and E _R.

Next, a schematic configuration of the steering torque correction value calculation device 50 will be described. FIG. 3 shows a block diagram of the steering torque correction value calculation device 50.
The steering torque correction value calculation device 50 includes a crawler track target speed determination device 51, a left proportional integration control device 52, a right proportional integration control device 53 corresponding to the left and right crawler belts 10, 11, and a torque correction amount minimum value detection. A device 54 is provided.
The target speed determination device 51 receives the accelerator amount and the steering amount from the accelerator pedal 20 and the steering 23, takes the steering amount into account, and determines the left and right track target speeds according to the accelerator amount (and the brake amount). Output to the proportional-integral control devices 52 and 53.

The proportional-integral control devices 52 and 53 output the left and right torque correction values according to the difference between the track target speed and the actual speed received from the left track speed meter 24 _L and the right track speed meter 24 _R, respectively.
The torque correction amount minimum value detection device 54 selects the value with the smaller absolute value from the received left and right torque correction values, and attaches the opposite sign to each of the left and right steering torque correction values D _L. as D _R, sent to adder.

Permanent magnet type synchronous motors 8 and 9 have a maximum output torque, but when a forward / reverse torque command value exceeding the maximum output torque is commanded, the commanded torque value cannot be obtained and a speed change occurs. there is a possibility. For this reason, in the present embodiment, by adopting the steering torque correction value having the smaller absolute value of the two steering torque correction values, the corrected motor torque command values E _L and E _R are obtained. The maximum output torque of the electric motors 8 and 9 is not exceeded.

  The torque correction amount minimum value detection device 54 receives the accelerator amount and the steering amount, and when the accelerator amount is 0, determines the outer wheel side based on the turning direction based on the steering amount, and the steering wheel torque correction value on the outer wheel side. Is set to 0, and the steering torque correction value on the inner ring side is output as it is.

Next, an outline of power control of the generator will be described based on FIG.
In the present embodiment, the power supplied to the electric motors 8 and 9 is the total power of the generator 2 and the battery 4, and the determination of the distribution is performed only by the operation control of the generator 2. That is, the converter 3 has a function of controlling the output of the generator 2 and controls the output of the generator 2 based on the generator torque command value Tg *.

Specifically, the control device 12 determines the target voltage command value Vbus * of the DC bus 5 in consideration of the voltage-power characteristic depending on the battery charge rate (SOC), and the target voltage command value Vbus * The generator torque command value Tg * is determined based on the actual DC bus voltage Vbus. Thereby, in this embodiment, the electric power control of the battery 4 can be performed indirectly by controlling the generator 2 and adjusting the voltage of the DC bus 5.
The battery charge rate (SOC) is an amount specified by “remaining battery capacity / full charge capacity of battery × 100 (%)”, and may be corrected in consideration of temperature.

  For this reason, in the present embodiment, the control device 12 includes a power control device 60. The power control device 60 includes a driving power calculation means 61, an engine maximum output calculation means 62, a battery output determination means 63, a battery power-voltage characteristic comparison means 64, a comparison means 65, and a DC bus voltage regulator 66. It has.

  The traveling power calculation means 61 calculates traveling power to be provided to the DC bus 5 based on the motor speed and the inverter torque command value (motor torque command value). For example, the electric power for traveling is required for the electric motors 8 and 9 based on the rotational speeds of the left and right motors and the motor torque command value calculated based on the accelerator amount, the brake amount, the shift position, the steering amount, and the like. Power can be calculated, and the actual power for driving the motors 8 and 9 can be calculated in consideration of the efficiency of the inverters 6 and 7 for each power for travel. Further, the power (auxiliary power) necessary for the operation of the electrical equipment that is an auxiliary machine (power load) connected to the DC bus 5 is calculated separately. The sum of the power for traveling and the power for auxiliary equipment is the required power.

  The engine maximum output calculation means 62 calculates the engine maximum output at that time of the engine 1 based on the rotational speed of the engine 1, the accelerator amount, the opening degree of the governor of the engine 1, and the like.

The battery output determination means 63 calculates the power (battery target output) to be output by the battery 4 by comparing the required power with the maximum output of the generator 2 obtained from the engine maximum output. For example, the battery target output is calculated by subtracting the maximum output of the generator 2 from the required power. Thereby, the power distribution of the engine 1 (or generator 2) and the battery 4 is specified.
The battery output determining unit 63 may be configured to adjust the power distribution according to the SOC of the battery 4.

  The battery power-voltage characteristic comparison unit 64 has a table in which the battery voltage and the battery power in the battery 4 are associated with each other. FIG. 4 shows an example of this table. The table is experimentally acquired in advance, and this example is in the form of a graph with the horizontal axis representing battery power (current) and the vertical axis representing battery voltage, and the battery voltage and battery input / output power for each SOC. The relationship is shown. In this example, the higher the SOC, the higher the battery voltage, and the lower the SOC, the lower the battery voltage tends to be. Further, the battery voltage tends to increase as the battery output power increases (that is, the discharge current increases), and the battery voltage tends to increase as the battery input power increases (that is, the charging current increases).

  The battery power-voltage characteristic comparison unit 64 can calculate the battery voltage from the table based on the received battery target output and SOC. This battery voltage becomes the voltage command value Vbus * for the DC bus 5.

Comparing means 65 compares DC bus voltage command value Vbus * with actual DC bus voltage Vbus, and outputs the comparison result to DC bus voltage regulator 66.
Based on the comparison result, the DC bus voltage regulator 66 calculates the torque command value Tg * of the generator 2 so that, for example, the DC bus voltage command value Vbus * matches the actual DC bus voltage Vbus, Output to the converter 3. The converter 3 receives the torque command value Tg * and controls the operation of the generator 2.

Next, based on FIG. 5, a reverse shift torque correction value calculation device that is a characteristic configuration of the present embodiment will be described.
As described above, when the shift lever is switched to the shift position corresponding to the direction opposite to the traveling direction during traveling of the vehicle 100 (that is, during reverse shifting), the control device 12 displays the forward / reverse torque command value. Instead of A _L and A _R , the reverse shift torque command values C _L and C _R are output to the inverters 6 and 7 as the forward / reverse torque command values B _L and B _R.

  Therefore, as shown in FIG. 5, the reverse shift torque correction value calculation device 40 of the control device 12 includes a regenerative power calculation means 41, a power torque conversion means 41 a, and a reverse shift accelerator torque command value calculation means 42. Vehicle speed calculation means 43, minimum value selection means 44, sign selection means 45, forward / reverse determination means 46, reverse shift determination means 47, torque command value switching means 48, and change rate limiting means 49. ing.

  The reverse transmission torque correction value calculation device 40 has a calculation portion corresponding to the left motor 8 and a calculation portion corresponding to the right motor 9, but FIG. 5 corresponds to the left motor 8. Only the calculation part is shown. Since the left and right calculation parts have the same configuration, the description of the calculation part corresponding to the right motor 9 is omitted.

  The regenerative power calculating means 41 is configured to calculate the power that the battery 4 can absorb or regenerate in the current charging state based on the SOC received from the battery management unit (BMU) attached to the battery 4. ing. For example, the regenerative power calculating means 41 has a battery SOC-regenerative power table that associates each SOC with power that can be accepted as regenerative power, and based on the obtained SOC using this table. The regenerative power (rechargeable power) is calculated.

This battery SOC-regenerative power table is based on the overvoltage upper limit value and the battery characteristics for the electric equipment connected to the DC bus 5 in consideration of the power conversion efficiency of the inverters 6 and 7 and the electric motors 8 and 9 as the generators. Can be determined in advance.
FIG. 5 shows an example of this table. In this example, the horizontal axis is SOC and the vertical axis is regenerative power, and the relationship between the SOC and regenerative power is shown. In the example of FIG. 5, the regenerative power becomes smaller as the SOC becomes larger.

The vehicle speed calculation means 43 receives the left and right crawler speeds from the crawler speed meters 24 _L and 24 _R provided in the left and right crawler belts 10 and 11, respectively, and calculates the average rotational speed and the vehicle speed of the electric motors 8 and 9 as the synchronous generator. calculate.
The power torque conversion means 41 a calculates a regenerative torque command value based on a value obtained by dividing the regenerative power received from the regenerative power calculation means 41 by the average rotation speed received from the vehicle speed calculation means 43.
The regenerative power calculation means 41 and the power torque conversion means 41a correspond to regenerative torque command value calculation means.

  The reverse shift accelerator torque command value calculation means 42 is in a direction opposite to the current traveling direction based on the amount of operation (accelerator amount) of the accelerator pedal 20 operated by the driver during reverse shift. A torque command value in the traveling direction corresponding to the shift position after the shifting operation is calculated.

  For example, the reverse shift accelerator torque command value calculating means 42 has a reverse shift accelerator amount-accelerator torque command value table in which a torque command value is associated with each accelerator amount for each shift position. Is used to calculate the reverse torque accelerator torque command value based on the acquired accelerator amount.

  FIG. 5 shows an example of this table. In this example, the horizontal axis represents the accelerator amount and the vertical axis represents the torque command value, and the relationship between the accelerator amount and the torque command value is shown. In the example of FIG. 5, the torque command value (absolute value) increases as the accelerator amount increases.

  In this embodiment, since the traveling direction corresponding to the D position is positive and the traveling method corresponding to the R position is negative, when the shift position is switched from the D position to the R position, a negative torque command value is obtained. On the contrary, when the R position is switched to the D position, a positive torque command value is calculated.

The minimum value selection means 44 selects a torque command value having a small absolute value from the received regenerative torque command value and the reverse shift accelerator torque command value. For example, in the reverse shift accelerator torque command value when the accelerator amount is large, the regenerative electric power may become too large. Therefore, by limiting the torque command value to the regenerative torque command value calculated based on the SOC. The overvoltage of the DC bus 5 can be prevented. On the other hand, when the SOC is small, there is a margin in the electric power that can be regenerated, so a large regenerative torque command value can be set. However, when the accelerator amount is small, the torque command value is calculated based on the accelerator amount. By limiting to the calculated reverse shift accelerator torque command value, the operation of the vehicle 100 unintended by the driver can be prevented.
The minimum value selection means 44 corresponds to torque command value selection means.

  The forward / reverse determination unit 46 determines the traveling direction of the vehicle 100 from the received vehicle speed. That is, the direction corresponding to the D position is forward, the direction corresponding to the R position is reverse, and the forward / reverse determination unit 46 determines whether the vehicle 100 is moving forward and backward, and sets a forward / backward determination flag.

Based on the received forward / reverse determination flag, the code selection unit 45 selects a code based on the following Table 1 and attaches it to the torque command value (absolute value) selected by the minimum value selection unit 44. For example, when the vehicle 100 is traveling forward, the shift position is switched to the R position, and the vehicle 100 is traveling forward in the reverse shift state where the vehicle 100 is still traveling forward, the forward / reverse determination flag is Set to forward. Further, the shift position is so the R position, the sign of the forward and reverse torque command value A _L becomes negative. Since the forward-reverse judgment flag is set to forward, the sign of the inverse transform time torque command value C _L is negative, will provide a deceleration torque.

  Based on the received forward / reverse determination flag and the shift position, the reverse shift determination means 47 determines whether or not the current situation is the reverse shift state, and outputs a reverse shift determination flag. That is, when the shift lever is in the R position even though the vehicle 100 is traveling forward, a reverse shift determination flag indicating that the reverse shift state is being output is output. The reverse shift determination flag is also output when the shift lever is in the D position even though the vehicle 100 is traveling backward.

The torque command value switching means 48 normally outputs the forward / reverse torque command value A _L received from the forward / reverse torque command value computing device 30 as the forward / reverse torque command value B _L. However, while the torque command value switching means 48 is in the reverse shift state and receives the reverse shift determination flag, the reverse shift torque command value C _L is used instead of the forward / reverse torque command value A _L. The output is switched so that the torque command _BL is output.
The torque command value switching means 48 corresponds to reverse torque torque command value output means.

Change rate limiting means 49, when a reverse shift operation is performed, the vehicle 100 when the forward-reverse torque command B _L is switched from the forward and reverse torque command value A _L of the reverse shift when the torque command value C _L This is to alleviate the impact in the front-rear direction applied to the head. For this reason, the change rate limiting means 49 is configured to limit the change rate to a predetermined threshold when the change rate of the forward / reverse torque command _BL is larger than a predetermined threshold.

As described above, in the present embodiment, the motor 8, 9 regenerates the DC bus 5 at the time of reverse shifting, so that the electric motor 8, 9 is limited according to the SOC of the battery 4 regardless of the accelerator amount. 9 is determined. (Torque command values for forward / reverse travel B _L , B _R ) Thereby, since regenerative electric power is suppressed below the electric power which can be absorbed with the battery 4 at the time of reverse gear shifting, it can prevent effectively that the direct-current bus 5 becomes overvoltage and an electric equipment breaks down. .

  In the present embodiment, the reverse shift accelerator torque command value calculating means 42 in the reverse shift torque correction value calculating device 40 calculates the torque command value based on the accelerator amount. The similar torque command value calculated by the similar means in the forward / reverse torque command value calculating device 30 is replaced with the torque command value from the reverse-shift accelerator torque command value calculating means 42, and is sent to the minimum value selecting means 44. You may comprise so that it may input.

Next, a second embodiment of the present invention will be described with reference to FIG.
This embodiment is a preferred embodiment when the shift position is switched to the reverse shift state while the vehicle 100 is traveling at a high speed (that is, in a state where the rotation speed of the electric motors 8 and 9 is high). That is, when the reverse shift state is entered during high-speed traveling, the regenerative power increases, and the risk of failure of the electrical equipment due to overvoltage increases. In the first embodiment, if a reverse speed change operation is performed during high-speed traveling, the torque command value is limited by the SOC of the battery 4 regardless of the accelerator amount, so there is a possibility that sufficient brake torque or deceleration torque cannot be obtained. There is.

In the present embodiment, even in such reverse gear shifting operation during high-speed traveling, a failure of the electric device due to overvoltage is prevented and a predetermined deceleration torque can be obtained. The specific configuration of this embodiment is shown in FIG. In this embodiment, the reverse transmission torque correction value calculation device 140 shown in FIG. 6 is used instead of the reverse transmission torque correction value calculation device 40 of FIG.
In FIG. 6 of the second embodiment, elements that are the same as those in the first embodiment shown in FIG.

  As shown in FIG. 6, the reverse shift torque correction value calculation device 140 includes the reverse shift vehicle speed torque command value calculation means 101, absolute value processing, in addition to the elements of the reverse shift torque correction value calculation device 40 of FIG. 5. Means 102, mechanical (mechanical) brake command value calculating means 103, mechanical brake command value switching means 104, change rate limiting means 105, mechanical brake command value determining means 106, torque command value difference calculating means 144a, It has.

  The reverse shift vehicle speed torque command value calculation means 101 is configured to calculate a torque command value (reverse shift vehicle speed torque command value) according to the vehicle speed. Specifically, the reverse shift vehicle speed torque command value calculation means 101 has a reverse shift vehicle speed-vehicle speed torque command table in which a torque command value for obtaining a deceleration torque is associated with a vehicle speed (absolute value). doing. FIG. 6 shows an example of this table. In this example, the horizontal axis represents the vehicle speed (absolute value) and the vertical axis represents the torque command value, and the relationship between the vehicle speed and the torque command value is shown. In this example, when the vehicle speed is equal to or less than a predetermined threshold, the torque command value is constant. When the vehicle speed is equal to or greater than the predetermined threshold, the torque command value decreases as the vehicle speed increases. Therefore, in the present embodiment, as the vehicle speed increases, the reverse speed vehicle speed torque command value can be reduced to prevent generation of excessive regenerative power.

  In this example, a constant torque command value is output at a vehicle speed equal to or lower than a predetermined threshold. However, such a threshold need not be provided. In this example, the torque command value is configured to gradually decrease as the vehicle speed increases. However, the present invention is not limited to this, and the torque command value decreases stepwise as the vehicle speed increases. It may be configured.

  More specifically, when the vehicle speed is equal to or higher than a predetermined threshold, the vehicle speed and the torque command value may be inversely proportional. In this case, a constant torque command value is output at a vehicle speed that is equal to or lower than a predetermined threshold value. However, at a vehicle speed that is equal to or higher than the predetermined threshold value, the product of the vehicle speed and the torque command value is a constant value. This constant value is a mechanical output value (for example, 50 kW) from the electric motors 8 and 9. Therefore, at a vehicle speed equal to or higher than a predetermined threshold, considering the efficiency (for example, 90%) of the synchronous motor and the inverter, a certain amount of power (for example, 40 kW = 50 kW × 0.9) is used as regenerative power to the DC bus 5. Can be regenerated.

For example, it is assumed that the SOC usage range of the battery 4 in a normal use state is 40 to 70%, and the battery 4 can be charged (regenerated) at an upper limit of 70% SOC. In this case, the battery 4 can always absorb at least 40 kW of regenerative power. For this reason, if this minimum regenerative power is set to the above-mentioned constant power, the reverse speed vehicle speed torque command value output from the reverse speed vehicle speed torque command value calculation means 101, as will be described later, When the torque command value B _L is selected, it is possible to prevent the regenerative power from being too large and causing the DC bus 5 to become overvoltage.
Therefore, when the product of the vehicle speed and the torque command value is set to a constant value in the reverse speed vehicle speed-vehicle speed torque command table, the constant value indicates the efficiency of the synchronous motor and the inverter, and the SOC usage range of the battery 4. It is desirable to set in consideration of (minimum power that can be regenerated).

  The absolute value processing means 102 receives a signal representing the vehicle speed from the vehicle speed computing means 43 and outputs a vehicle speed absolute value signal representing the magnitude of the vehicle speed to the reverse speed vehicle speed torque command value computing means 101. The reverse speed vehicle speed torque command value calculation means 101 acquires the vehicle speed (absolute value) from the vehicle speed absolute value signal.

  The torque command value difference calculation means 144a is a difference (absolute value) obtained by subtracting the torque command value selected by the minimum value selection means 44 from the reverse shift accelerator torque command value output by the reverse shift accelerator torque command value calculation means 42. Is calculated and output as a mechanical brake correction torque command value.

  That is, the driver expects that a deceleration torque corresponding to the accelerator amount can be obtained by operating the accelerator pedal 20, but if the selected torque command value is smaller than the accelerator torque command value at the time of reverse shifting. Therefore, the expected deceleration torque cannot be obtained. Therefore, in the present embodiment, the torque command value difference calculating means 144a outputs a mechanical brake correction torque command value so that a predetermined deceleration torque can be obtained by obtaining an insufficient deceleration torque with a mechanical brake device.

  As a result, the brake torque applied to the entire vehicle 100 (that is, the sum of the regenerative torque by the electric motors 8 and 9 and the braking torque by the mechanical brake device) at the time of reverse shifting is set to the accelerator amount regardless of the vehicle speed and the SOC of the battery 4 Since it can generate | occur | produce correspondingly, it becomes possible to obtain required brake torque.

  The mechanical brake command value calculation means 103 has a mechanical brake command calculation table in which a mechanical brake command value (%) for operating the mechanical brake is associated with the mechanical brake correction torque command value. The mechanical brake command value G is calculated based on the received mechanical brake correction torque command value. The mechanical brake command value is represented by 0% to 100% from a state where the effect without brake is obtained to a state where the effect of full brake is obtained.

  FIG. 6 shows an example of this table. In this example, the horizontal axis represents the mechanical brake correction torque command value Tm * and the vertical axis represents the mechanical brake command value (%). The mechanical brake correction torque command value Tm * and the mechanical brake command value (%) The relationship is shown. In the example of the table of FIG. 6, the mechanical brake command value G increases as the mechanical brake correction torque command value increases within a range where the mechanical brake correction torque command value is less than or equal to a predetermined threshold value. G becomes constant (100%).

The mechanical brake command value determining means 106 calculates a mechanical brake command value F for operating the mechanical brake based on an operation amount (brake amount) by which the driver operates the brake pedal 21.
The mechanical brake command value switching means 104 normally outputs the mechanical brake command value F received from the mechanical brake command value determining means 106 to the mechanical brake. However, while the reverse shift determination flag indicating the reverse shift state is received from the reverse shift determination unit 47, the mechanical brake command value G received from the mechanical brake command value calculation unit 103 is set to the mechanical brake command value F. Instead, it outputs to the mechanical brake.
Therefore, in this embodiment, even if the driver does not operate the brake pedal 21 during reverse gear shifting, the mechanical brake is actuated supplementarily to compensate for the shortage of deceleration torque.

  The rate-of-change limiting means 105 is for reducing the longitudinal impact applied to the vehicle 100 by the operation of the mechanical brake when the reverse speed change operation is performed. Therefore, the change rate limiting means 105 is configured to limit the change rate to a predetermined threshold when the change rate from the mechanical brake command value F to the mechanical brake command value G is larger than a predetermined threshold. .

  As described above, in this embodiment, even if regenerative braking is suppressed to prevent the regenerative power from becoming excessively large at the time of reverse gear shifting and sufficient deceleration torque cannot be obtained, the shortage is reduced. It is configured to compensate by a mechanical brake. Thus, in the present embodiment, it is possible to prevent the DC bus 5 from being overvoltage due to regenerative power and causing the electric device to fail, and to ensure a predetermined deceleration torque. Such an effect is particularly prominent when a reverse speed change operation is performed during high speed traveling.

40, 140 Reverse shift torque correction value calculation device 41 Regenerative power calculation means 41a Power torque conversion means 42 Reverse shift accelerator torque command value calculation means 44 Minimum value selection means 47 Reverse shift determination means 48 Torque command value switching means 100 Hybrid vehicle 101 reverse gear shifting speed torque command value calculating means 103 mechanical brake command value calculating unit 144a torque command value difference calculation means A _L, A _R forward and reverse torque command value B _L, B _R forward and reverse torque command value C _L, C _R Reverse speed torque command value D _L , D _R Steering torque correction value E _L , E _R motor (inverter) torque command value

Claims (8)

An engine, a generator driven by the engine, a battery, and driving using the power from the generator and / or the battery based on a torque command value to provide driving power to the outside and regenerative power An electric motor capable of providing the battery to the battery, and a hybrid vehicle control device comprising:
Reverse shift determining means for determining whether or not the shift position is in a reverse shift state at a reverse shift position corresponding to a direction opposite to the vehicle traveling direction;
Torque with smaller absolute value among regenerative torque command value calculated based on electric power that can be accepted as regenerative power by battery and accelerator torque command value in reverse direction determined according to accelerator amount Torque command value selection means for selecting a command value;
A reverse-shift-time torque command value output means for outputting the torque command value selected by the torque command value selection means to the motor when the reverse-shift determination means determines that the reverse shift state is established;
The control apparatus of the hybrid vehicle provided with. The torque command value selection means includes regenerative torque command value calculation means,
The regenerative torque command value calculation means calculates rechargeable power that can be received by the battery based on the SOC of the battery, and sets the regenerative torque command value to regenerate the rechargeable power by the electric motor. A control device for a hybrid vehicle, characterized in that it calculates.   3. The hybrid vehicle according to claim 2, wherein the regenerative torque command value calculation unit calculates the regenerative torque command value based on a value obtained by dividing the chargeable power by a rotation speed of the electric motor. Control device. The control means further comprises mechanical brake command value output means,
The mechanical brake command value output means provides a brake command to a mechanical brake device that directly or indirectly brakes the electric motor so as to obtain a predetermined deceleration torque regardless of the amount of operation of the brake pedal in the reverse shift state. The hybrid vehicle control device according to claim 1, wherein:   5. The hybrid according to claim 4, wherein the mechanical brake command value output means calculates the brake command so as to compensate for a difference between the accelerator torque command value and the selected torque command value. Vehicle control device. The torque command value selection means includes an accelerator torque command value calculation means,
6. The control apparatus for a hybrid vehicle according to claim 1, wherein the accelerator torque command value calculating means calculates the accelerator torque command value from a torque command value table associated with an accelerator amount. The torque command value selection means includes vehicle speed torque command value calculation means,
The vehicle speed torque command value calculating means calculates a vehicle speed torque command value in the reverse direction according to the vehicle speed,
The torque command value selection means is configured to select the smallest torque command value from the three torque command values of the regenerative torque command value, the accelerator torque command value, and the vehicle speed torque command value. The control apparatus for a hybrid vehicle according to any one of claims 1 to 6.   The vehicle speed torque command value calculation means calculates the vehicle speed torque command value so that a value obtained by multiplying the vehicle speed torque command value by a vehicle speed becomes a constant value, and the constant value is preset. The hybrid vehicle control device according to claim 7.

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