Vehicle control method and vehicle control device

Abstract

To provide a vehicle control method and a vehicle control device which may suppress variation in power to be input to a battery in such a scene that there is the need to protect the battery for a vehicle having the battery which is charged with the power generated by a power generator driven by a power source.SOLUTION: An electric vehicle 100 comprises: an engine 17; a power generator 18 which is driven by the engine 17; and a battery 10 which is charged with the power generated by the power generator 18. In the electric vehicle 100, a rotation frequency of the power generator 18 is controlled with rotation frequency control that feeds back a rotation frequency detection value ωg of the power generator 18, necessity of protecting the battery 10 is also determined on the basis of the state of the battery 10, and, when it is determined that the protection of the battery 10 is needed, responsibility of the rotation frequency control is reduced in comparison with a case where the protection of the battery 10 is not needed.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a vehicle control method and a vehicle control device for controlling a vehicle in which a battery is charged with electric power generated by a generator. [Background technology]

[0002] Patent Document 1 describes a hybrid vehicle equipped with an engine and a motor generator for driving the vehicle. In this hybrid vehicle, the engine is used to drive the motor generator, and the rotation speed of the motor generator is controlled to keep the rotation speed constant. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-030560 Summary of the Invention [Problem to be solved by the invention]

[0004] A vehicle may be equipped with a power generation system including a power source such as an engine, a generator driven by the power source, and a battery charged with the power generated by the generator. In a vehicle equipped with such a power generation system, the rotation speed of the generator may be controlled by a rotation speed control that feeds back a detected value of the rotation speed of the generator in order to stably supply power to the battery.

[0005] However, if the rotation speed control used in the vehicle drivetrain is directly applied to the rotation speed control of the power generation system, problems will arise in terms of protecting the battery.

[0006] Specifically, the rotation speed control performed in a vehicle drivetrain is usually made as responsive as possible so as to be able to respond to various disturbances. However, for example, when the battery is at a low temperature, the input power or output power of the battery may be limited to protect the battery. Therefore, a highly responsive rotation speed control for a vehicle drivetrain may respond too sensitively to disturbances such as engine torque pulsation when battery protection is required, and the input voltage to the battery may exceed the limited allowable input voltage. For this reason, if a highly responsive rotation speed control for a vehicle drivetrain is adopted as the rotation speed control for a power generation system, a torque limit sufficient for the generator to follow cannot be set, and the engine undergoing torque control may over-rev (so-called over-revving).

[0007] The present invention aims to provide a vehicle control method and a vehicle control device that can suppress fluctuations in power input to a battery in a situation where it is necessary to protect the battery, for a vehicle having a battery that is charged with power generated by a generator driven by a power source. [Means for solving the problem]

[0008] One aspect of the present invention is a vehicle control method for controlling a vehicle having a power source that generates power, a generator driven by the power, and a battery that is charged with the electric power generated by the generator. In this vehicle control method, the rotation speed of the generator is controlled by a rotation speed control that feeds back the rotation state of the generator. Also, The available input voltage and / or available output voltage of the battery are calculated based on the temperature, voltage, current, and / or charging rate of the battery, and it is determined whether or not battery protection is necessary based on the available input voltage and / or available output voltage. When it is determined that battery protection is necessary, the response of the rotation speed control is reduced compared to when battery protection is not necessary. [Effects of the Invention]

[0009] According to the present invention, for a vehicle having a battery that is charged with electricity generated by a generator driven by a power source, a vehicle control method and a vehicle control device can be provided that can suppress fluctuations in power input to the battery in situations where the battery needs to be protected. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is an explanatory diagram showing a schematic configuration of an electric vehicle. [Figure 2] FIG. 2 is a block diagram showing the configuration of the generator controller. [Figure 3] FIG. 3 is a block diagram showing the configuration of the rotation speed control unit. [Figure 4] FIG. 4 is a graph showing the engine torque, the detected rotation speed, and the input power to the battery under the control of the comparative example. [Figure 5] FIG. 5 is a graph showing the engine torque, the detected rotation speed, and the input power to the battery under the control of the first embodiment. [Figure 6] FIG. 6 is a block diagram showing the configuration of the rotation speed control unit of the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0012] [First embodiment] 1 is an explanatory diagram showing a schematic configuration of an electric vehicle 100. As shown in FIG.

[0013] The battery 10 stores electric power for driving each part of the electric vehicle 100. The battery 10 is rechargeable. In this embodiment, the battery 10 is charged by at least the electric power generated by the power generation system 12. In this embodiment, the battery 10 is a DC power supply. The DC voltage output by the battery 10 (hereinafter referred to as the battery voltage V dc ) can be detected by a sensor or the like (not shown).

[0014] The drive motor 11 is an electric motor for driving the electric vehicle 100, and generates a driving force for the electric vehicle 100 using the electric power of the battery 10. In this embodiment, the drive motor 11 is a three-phase AC motor.

[0015] The drive motor 11 is connected to a drive shaft 14 via a reducer 13 and the like. Drive wheels 15 are connected to the drive shaft 14. Therefore, the torque generated on the output shaft of the drive motor 11 generates a driving force for the electric vehicle 100 in the drive wheels 15 via the reducer 13 and the like. Furthermore, when the electric vehicle 100 decelerates, the drive motor 11 converts the kinetic energy of the electric vehicle 100 into electrical energy through so-called regenerative control. Some or all of the electric power obtained during regenerative control can be charged to the battery 10.

[0016] The drive motor 11 is connected to the battery 10 via a drive inverter 16. The drive inverter 16 is an inverter for the drive motor 11, and converts DC power output by the battery 10 into AC power and supplies it to the drive motor 11. During regenerative control, the drive inverter 16 also converts AC power generated by the drive motor 11 into DC power.

[0017] The power generation system 12 is a system that generates electric power to charge the battery 10. That is, the electric vehicle 100 of this embodiment is a so-called series hybrid electric vehicle. The power generation system 12 includes an engine 17 and a generator 18.

[0018] The engine 17 is a so-called internal combustion engine, and is the power source of the power generation system 12. That is, the generator 18 generates electricity using the power generated by the engine 17. Note that in this embodiment, the power generation system 12 uses the engine 17, which is an internal combustion engine, as the power source, but the engine 17 may be replaced with another type of power source that can drive the generator 18. Parameters related to the operating state of the engine 17, such as the rotation speed of the engine 17 (hereinafter referred to as engine rotation speed), can be detected as appropriate by a sensor (not shown) or the like.

[0019] The generator 18 generates electricity using the power of the engine 17. That is, the generator 18 generates electricity by rotating due to the driving force of the engine 17. The generator 18 is connected to the battery 10 via a generator inverter 20, and the generated electricity is charged into the battery 10. The generator inverter 20 converts AC power generated by the generator 18 into DC power and supplies it to the battery 10. The generator inverter 20 also converts DC power from the battery 10 into AC power and supplies it to the generator 18, allowing the generator 18 to power-run. As a result, when the engine 17 is started, the engine 17 is cranked. Furthermore, the generator 18 is power-run to idle the engine 17 as needed, thereby consuming power from the battery 10. This operating mode of idling the engine 17 is called motoring.

[0020] In this embodiment, the generator 18 is a three-phase AC generator having a U phase, a V phase, and a W phase. The detected value of the current flowing through the U phase of the generator 18 is the U-phase current Iu. Similarly, the detected value of the current flowing through the V phase of the generator 18 is the V-phase current Iv, and the detected value of the current flowing through the W phase of the generator 18 is the W-phase current Iw. Hereinafter, the detected values of the current flowing through each phase of the generator 18 may be collectively referred to as the three-phase current. The detected value of the d-axis current of the generator 18 is the d-axis current I d and the detected value of the q-axis current of the generator 18 is the q-axis current I q The d-axis current I d and q-axis current I q is detected by converting the three-phase current. In the following, the d-axis current I of the generator 18 is d and q-axis current I q The dq axis current I d ,I q In addition, the rotation speed detection value ω g The rotational speed detection value ω can be detected by a sensor (not shown) or the like. g is one form of parameter that represents the rotation state of the generator 18. In this embodiment, in various controls, the rotation speed detection value ω gis used, but the rotation speed detection value ω g Instead of this, other parameters that represent the rotational state of the generator 18, such as the rotational speed of the generator 18, can be used.

[0021] In addition to the power generation system 12 and the like, the electric vehicle 100 is equipped with various controllers (see FIG. 1) for controlling the traveling and the power generation system 12. Specifically, as shown in FIG. 1, the electric vehicle 100 is equipped with a system controller 21, a drive motor controller 22, a battery controller 23, a generator controller 24, and an engine controller 25. In this embodiment, the system controller 21 is equipped with a power generation control unit 26.

[0022] The system controller 21 is a higher-level control unit that uses vehicle information to comprehensively control each part of the electric vehicle 100. The vehicle information is parameters that represent the operating state of each part of the electric vehicle 100. For example, the vehicle information includes parameters that represent the driving state of the electric vehicle 100, such as the accelerator opening Apo, which is the amount of accelerator pedal operation by the driver, the vehicle speed V, and the gradient of the road surface on which the electric vehicle 100 is located. In addition, the vehicle information includes various parameters that represent the state of the battery 10, such as the temperature of the battery 10, the voltage, current, internal resistance related to the input and / or output, and the state of charge (SOC). In addition, the vehicle information also includes parameters that represent the internal state of the electric vehicle 100, such as the power generated by the power generation system 12. For example, the detected value ω of the rotation speed of the generator 18 g , d-axis current I d , and q-axis current I q The vehicle information includes the rotation speed of the engine 17, etc. These are examples of parameters that represent the rotation state of the generator 18. The battery voltage V dc is vehicle information. This vehicle information is obtained directly using sensors or the like, or indirectly through calculations using the vehicle information. The system controller 21 can obtain this various vehicle information as needed using sensors (not shown) and the various controllers described above.

[0023] The system controller 21 calculates a motor torque command value using one or more pieces of vehicle information. The motor torque command value is a command value that indicates a target torque to be output by the drive motor 11. Therefore, the system controller 21 operates as a motor torque command value calculation unit that calculates a motor torque command value for driving the electric vehicle 100. The motor torque command value is input to the drive motor controller 22. In this embodiment, the system controller 21 calculates the drive torque command value in accordance with the accelerator opening Apo, vehicle speed V, SOC of the battery 10, available input power (available input voltage and / or available input current), available output power (available output voltage and / or available output current), power generated by the generator 18, etc.

[0024] The system controller 21 calculates the target power generation using one or more pieces of vehicle information. The target power generation is a target value of power to be generated by the power generation system 12 to charge the battery 10 and / or supply to the drive motor 11. Therefore, the system controller 21 operates as a target power generation calculation unit that calculates the target power generation for power generation in the electrically powered vehicle 100. The calculated target power generation is input to the power generation control unit 26.

[0025] The power generation control unit 26 controls the power generation by the power generation system 12 based on the target power generation. Specifically, the power generation control unit 26 controls the generator rotation speed command value ω g * and the engine torque command value T E * and the power generation system 12 is operated based on these.

[0026] Generator rotation speed command value ω g * is a target value (command value) for the rotational speed that the generator 18 should maintain in order to realize the power generation of the target generated power by the power generation system 12. g * is input to the generator controller 24.

[0027] Engine torque command value T E * is a target value (command value) for the torque that the engine 17 should output in order to achieve the target generated power by the power generation system 12. E * is input to the engine controller 25. The power generation control unit 26 also receives the rotation speed detection value ω of the generator 18. g Monitor.

[0028] In this embodiment, the power generation control unit 26 is provided in the system controller 21, but the power generation control unit 26 may be provided independently of the system controller 21, similar to the generator controller 24 and the engine controller 25.

[0029] The drive motor controller 22, the battery controller 23, the generator controller 24, and the engine controller 25 are lower-level control units that individually control the respective parts of the electric vehicle 100 based on commands from the system controller 21.

[0030] The drive motor controller 22 switches the drive inverter 16 based on the drive torque command value and in accordance with the state of the drive motor 11, such as the rotation speed and voltage. In this way, the drive motor controller 22 operates the drive motor 11 so as to generate the drive torque commanded by the system controller 21.

[0031] The battery controller 23 acquires parameters (vehicle information) that represent the state of the battery 10, such as the temperature, voltage, current, internal resistance, and SOC of the battery 10, using sensors (not shown) or by calculation. For example, the battery controller 23 measures the SOC based on the current and voltage discharged or charged by the battery 10. The measured SOC is output to the system controller 21. The battery controller 23 also calculates the available input power and available output power of the battery 10 according to the temperature, internal resistance, and / or SOC of the battery 10. The calculation results of the available input power and available output power are output to the system controller 21.

[0032] In addition, the battery controller 23 determines whether or not it is necessary to protect the battery 10. That is, the battery controller 23 functions as a protection necessity determination unit for the battery 10. The necessity of protecting the battery 10 is determined based on various parameters related to the battery 10, such as the temperature, voltage, current, and / or SOC of the battery 10. Furthermore, it is determined that the battery 10 needs to be protected when it is necessary to limit the input voltage to the battery 10 and / or when it is necessary to limit the output power from the battery 10. Typically, it is determined that the battery 10 needs to be protected when the battery 10 is at a low temperature. The battery controller 23 outputs the determination result regarding the necessity of protecting the battery 10 as a battery protection flag FLG to the system controller 21. The system controller 21 inputs the battery protection flag FLG to the generator controller 24 via the power generation control unit 26. In the generator controller 24, the battery protection flag FLG indicates the limited state of the inputtable power and / or outputtable power of the battery 10.

[0033] In this embodiment, the battery controller 23 determines the need for battery protection, but the system controller 21 may determine the need for protection of the battery 10. In this case, the system controller 21 constitutes a protection necessity determination unit for the battery 10.

[0034] The generator controller 24 controls the operation of the generator 18. More specifically, the generator controller 24 controls the operation of the generator 18 by setting a generator rotation speed command value ω g * , the generator inverter 20 is switched on and off in accordance with the state of the generator 18, such as the rotation speed and voltage, based on the detected rotation speed value ω. In this way, the generator controller 24 operates the generator 18 so as to generate the target generated power. In this embodiment, the generator controller 24 g The rotation speed of the generator 18 is controlled by feedback control of the rotation speed of the generator 18. The configuration of the generator controller 24 will be described in detail later.

[0035] The engine controller 25 is a power source controller that controls the operation of the engine 17, which is a power source. More specifically, the engine controller 25 controls the engine torque command value T E * Based on this, the engine controller 25 adjusts the throttle, ignition timing, and / or fuel injection amount of the engine 17 in accordance with signals such as the rotation speed and temperature of the engine 17. In this way, the engine controller 25 causes the engine 17 to generate power that achieves the target power generation. Signals such as the rotation speed and temperature of the engine 17 are appropriately acquired by sensors (not shown) or the like.

[0036] The system controller 21, drive motor controller 22, battery controller 23, generator controller 24, and engine controller 25 are each configured with one or more computers. That is, each of these controllers includes, partially or as a whole, a central processing unit (CPU), a random access memory (RAM), an input / output interface (I / O interface), etc. Furthermore, these controllers are programmed to periodically execute the various controls described above at predetermined control intervals.

[0037] In this embodiment, the above-described various controllers are described separately, but some or all of these controllers may be configured as an integrated unit. For example, the above-described various controllers may be implemented as a whole on a single computer. Also, some of the above-described various controllers may be implemented on a single computer, for example, by implementing the generator controller 24 and the engine controller 25 on a single computer. In other words, the classification of the above-described various controllers is merely for the convenience of explanation. Therefore, the above-described various controllers as a whole constitute a vehicle control device that controls the electric vehicle 100.

[0038] Of the various controllers described above, the generator controller 24, the engine controller 25, the power generation control unit 26, and the battery controller 23 are controllers that are particularly directly related to the control of the power generation system 12. Therefore, the generator controller 24, the engine controller 25, the power generation control unit 26, and the battery controller 23 constitute a power generation system control device 101 that controls the power generation system 12.

[0039] <Configuration of generator controller> Fig. 2 is a block diagram showing the configuration of the generator controller 24. As shown in Fig. 2, the generator controller 24 includes a rotation speed control unit 31, a current command value calculation unit 32, a current control unit 33, a decoupling control unit 34, a current converter 35, and a voltage converter 36.

[0040] The rotation speed control unit 31 calculates the generator rotation speed command value ω g * , rotation speed detection value ω g , and the final torque command value Tω, which is the final torque command value for the rotation speed control mode, based on the battery protection flag FLG. * Calculate the final torque command value Tω * is a target value (command value) for the torque that the generator 18 should generate in order to realize the power generation of the target power generation while maintaining the rotation speed of the generator 18. *is input to the current command value calculation unit 32. The configuration of the rotation speed control unit 31 will be described in detail later.

[0041] The current command value calculation unit 32 calculates the final torque command value Tω * , rotation speed detection value ω g , battery voltage V dc Using this, the d-axis current command value I d * and q-axis current command value I q * Calculate the d-axis current command value I d * is the final torque command value Tω * In order to realize a torque according to d Similarly, the q-axis current command value I q * is the final torque command value Tω * In order to realize a torque according to q The d-axis current command value I d * and q-axis current command value I q * is input to the current control unit 33.

[0042] The current control unit 33 controls the generator 18 by so-called current control. Specifically, the current control unit 33 controls the generator 18 by controlling the d-axis current command value I d * , q-axis current command value I q * , d-axis current I d , q-axis current I q , and the rotation speed detection value ω g Using this, the d-axis voltage command value V d * and q-axis voltage command value V q * Calculate the d-axis voltage command value V d * is the d-axis voltage V of the generator 18 d Similarly, the q-axis voltage command value V q * is the q-axis voltage V of the generator 18 qThe d-axis voltage command value V d * is input to the voltage converter 36 after the subtraction unit 38 subtracts the non-interacting voltage from the d-axis voltage. d * is the final d-axis voltage command value for the generator 18 (hereinafter referred to as the d-axis final voltage command value V′ d * The q-axis voltage command value V q * is input to the voltage converter 36 after the subtraction unit 39 subtracts the non-interacting voltage from the q-axis voltage. q * is the final q-axis voltage command value for the generator 18 (hereinafter referred to as the q-axis final voltage command value V′ q * In the following, the d-axis final voltage command value V' d * and the q-axis final voltage command value V' q * The final dq-axis voltage command value V′ d * ,V′ q * It may be collectively referred to as.

[0043] The decoupling control unit 34 controls the d-axis current I d and q-axis current I q The decoupling voltage control voltage is calculated using the above formula. Decoupling refers to reducing the voltage drop due to interference between the d-axis and q-axis. The decoupling voltage is an adjustment value for decoupling the d-axis voltage and the q-axis voltage, and is calculated for each of the d-axis and q-axis. As described above, these decoupling voltages are calculated by subtracting the d-axis voltage command value V d * and q-axis voltage command value V q * is subtracted from

[0044] The current transformer 35 converts the three-phase current I u ,I v ,I w The dq axis current Id ,I q Convert to three-phase current I u ,I v ,I w is detected by a current sensor 40 provided between the generator inverter 20 and the generator 18. In this embodiment, the U-phase current I u and V-phase current I v is detected, and the current converter 35 converts the W-phase current I w is calculated. The dq axis current I d ,I q is input to the current command value calculation unit 32 and the non-interference control unit 34, as described above.

[0045] The voltage converter 36 converts the dq-axis final voltage command value V' d * ,V′ q * From the voltage command value of each UVW phase (three-phase voltage command value) V u * ,V v * ,V w * These three-phase voltage command values V u * ,V v * ,V w * are input to the generator inverter 20. In response to these, the generator inverter 20 outputs a U-phase voltage V u , V phase voltage V v , and W-phase voltage V w As a result, the generator 18 applies the final torque command value Tω * The engine is driven at a rotation speed and torque according to the

[0046] <Configuration of rotation speed control unit> 3 is a block diagram showing the configuration of the rotation speed control unit 31. As shown in FIG. 3, the rotation speed control unit 31 includes a model matching compensation unit 41, a disturbance observer 42, and a torque command value calculation unit 43.

[0047] The model matching compensation unit 41 is configured to calculate the rotation speed of the generator 18 (detected rotation speed value ωg ) is the generator rotation speed command value ω g * The model matching compensation unit 41 includes a first model matching gain multiplication unit 51, a model matching filter 52, a subtraction unit 53, and a second model matching gain multiplication unit .

[0048] The first model matching gain multiplication unit 51 multiplies the generator rotation speed command value ω g * is multiplied by a first model matching gain gc. The first model matching gain gc is calculated by multiplying the total inertia J of the modeled power generation system 12, the design value J' of the total inertia of the generator 18, the engine 17, the gears, etc., the design value C' of the viscous friction coefficient, the time constant T of the target response, m Using the above, it is expressed by the following equation (1). The total inertia J and the design value of the total inertia J' are values converted to the generator shaft. The design value of the total inertia J' and the design value of the viscous friction coefficient C' are set to be equal to the characteristics of the actual controlled object. Time constant T m is determined in principle so that the model matching compensator 41 responds as quickly as possible without impairing control stability. Hereinafter, the time constant Tm determined in this way so that the model matching compensator 41 responds as quickly as possible will be referred to as the reference time constant of the model matching compensator 41.

[0049]

number

[0050] The model matching filter 52 calculates the rotation speed detection value ω g The model matching filter 52 is, for example, a low-pass filter, and has a transfer characteristic H mm It is represented by (s), where "s" is the Laplace operator.

[0051]

number

[0052] The subtractor 53 subtracts the generator rotation speed command value ω multiplied by the first model matching gain gc. g * (i.e., gc ω g * ) to obtain the rotation speed detection value ω processed by the model matching filter 52. g (i.e., H mm (s)·ω g The calculation result by the subtraction unit 53 is input to the second model matching gain multiplication unit 54.

[0053] The second model matching gain multiplication unit 54 multiplies the output of the subtraction unit 53 by the second model matching gain cp. The second model matching gain cp is expressed by the following equation (3).

[0054]

number

[0055] The model matching compensation unit 41 multiplies the output of the second model matching gain multiplication unit 54 by the first torque target value Tω1 * and outputs the first torque target value Tω1 to the torque command value calculation unit 43. * is the target value of the generator torque determined by model matching, as described above.

[0056] The disturbance observer 42 determines a torque target value (hereinafter referred to as a second torque target value Tω2 * ) to the final torque command value Tω * and the rotation speed detection value ω g and a disturbance observer filter. * is the first torque target value Tω1 * Second torque target value Tω2 *In this embodiment, the disturbance observer 42 includes a first disturbance observer filter 56, a second disturbance observer filter 57, and a subtraction unit 58.

[0057] The first disturbance observer filter 56 calculates the final torque command value Tω * Based on this, the second torque target value Tω 2* The first term (first element) Tω for calculating 2a * The first disturbance observer filter 56 is configured, for example, by a band-pass filter H(s). The band-pass filter H(s) configuring the first disturbance observer filter 56 is expressed by the following equation (4) using a time constant Th. In principle, the time constant Th is determined so that the disturbance observer 42 responds to disturbances as quickly as possible without impairing control stability. Hereinafter, the time constant Th determined in this way so that the disturbance observer 42 responds to disturbances as quickly as possible will be referred to as the reference time constant of the disturbance observer 42.

[0058]

number

[0059] The second disturbance observer filter 57 detects the rotation speed ω g Based on this, the second torque target value Tω2 * The second term (second element) Tω for calculating 2b * The second disturbance observer filter 57 is expressed by, for example, a band-pass filter H(s) and a ratio H(s) / Gp'(s) of a transfer characteristic Gp'(s). The transfer characteristic Gp'(s) is a filter that calculates the ratio of a rotation speed (detected rotation speed value ω g ) and is expressed by the following equation (5).

[0060]

number

[0061] The subtractor 58 subtracts the first term Tω 2a * From the second term Tω 2b * The second torque target value Tω2 is obtained by subtracting * The second torque target value Tω2, which is the calculation result of the subtraction unit 58, is calculated. * is input to the torque command value calculation unit 43.

[0062] The torque command value calculation unit 43 calculates the first torque target value Tω1 obtained from the model matching compensation unit 41. * The second torque target value Tω2 obtained from the disturbance observer 42 * By feeding back the final torque command value Tω * In this embodiment, the torque command value calculation unit 43 is an adder, and calculates the first torque target value Tω1 * Second torque target value Tω2 * By adding * The generator 18 is driven in accordance with this final torque command value Tω*.

[0063] The final torque command value Tω * The torque due to disturbances such as compression reaction force of the engine 17, combustion torque pulsation, and abnormal combustion (disturbance torque T d ) may be superimposed. g The disturbance rotation speed ω d 4, the power generation system 12 to be controlled is represented by a transfer function Gp(s). The transfer function Gp(s) is expressed by the following equation (6) using the total inertia J of the power generation system 12 and the viscous friction coefficient C.

[0064]

number

[0065] The basic configuration of the rotation speed control unit 31 is as described above. In addition, in this embodiment, when it is determined that protection of the battery 10 is necessary, the rotation speed control unit 31 reduces the responsiveness of the rotation speed control compared to when protection of the battery 10 is not necessary.

[0066] For this reason, among the components constituting the rotation speed control unit 31, the model matching compensator 41 and / or the disturbance observer 42 are configured to receive the battery protection flag FLG. The rotation speed control unit 31 reduces the responsiveness of the rotation speed control by adjusting the characteristics of the model matching compensator 41 and / or the characteristics of the disturbance observer 42 in accordance with the battery protection flag FLG. The rotation speed control unit 31 reduces the responsiveness of the rotation speed control when it is determined by the battery protection flag FLG that protection of the battery 10 is necessary, i.e., when the input voltage to the battery 10 and / or the output voltage of the battery 10 are limited.

[0067] In the following, as an example, it is assumed that the rotation speed control unit 31 adjusts the characteristics of the model matching compensator 41 so as to reduce the responsiveness of the model matching compensator 41, and adjusts the characteristics of the disturbance observer 42 so as to reduce the responsiveness of the disturbance observer 42. In other words, the rotation speed control unit 31 reduces the responsiveness of both the model matching compensator 41 and the disturbance observer 42, thereby reducing the responsiveness of the rotation speed control.

[0068] The characteristics of the model matching compensator 41 are adjusted as follows. That is, when protection of the battery 10 is necessary, the rotation speed controller 31 increases the time constant of the model matching compensator 41 to be greater than the reference time constant (Tm) when protection of the battery 10 is not necessary. This increases, for example, the time constant of the model matching filter 52. Therefore, when the detected rotation speed value ω g Even if a sudden change occurs in the engine 17, such a sudden change is smoothed by the model matching filter 52. Therefore, the response of the model matching to disturbances of the engine 17 and the like is reduced.

[0069] The degree to which the time constant of the model matching compensator 41 is reduced, i.e., the value of the time constant after reduction, is predetermined by adaptation depending on, for example, the specific configuration of the power generation system 12. Note that, with regard to model matching, the rotation speed controller 31 can adjust the value of the time constant after reduction depending on the degree of restriction on the input voltage to the battery 10 and / or the output voltage from the battery 10. For example, the rotation speed controller 31 can adjust the value of the time constant after reduction depending on the degree of restriction on the input voltage P lim And / or the time constant after reduction may be changed depending on the available output voltage.

[0070] The characteristics of the disturbance observer 42 are adjusted as follows. That is, when protection of the battery 10 is necessary, the rotation speed control unit 31 increases the time constant of the disturbance observer 42 to be greater than the reference time constant (Th) when protection of the battery 10 is not necessary. This increases the time constant of the first disturbance observer filter 56, which is made up of a band-pass filter H(s). Also, in the second disturbance observer filter 57, which includes the band-pass filter H(s), the time constant of the band-pass filter H(s) portion increases. Therefore, when a disturbance or the like of the engine 17 causes the detected rotation speed value ω g Even if a sudden change occurs in the output voltage, such a sudden change is smoothed out in the disturbance observer 42. Therefore, the responsiveness of the disturbance observer 42 to a disturbance of the engine 17 or the like is reduced.

[0071] The degree to which the time constant of the disturbance observer 42 is reduced, i.e., the value of the time constant after the reduction, is predetermined by adaptation depending on the specific configuration of the power generation system 12. Note that the rotation speed control unit 31 can adjust the value of the time constant after the reduction for the disturbance observer 42 depending on the degree of limitation on the input voltage to the battery 10 and / or the output voltage from the battery 10. For example, the rotation speed control unit 31 can adjust the value of the time constant after the reduction depending on the degree of limitation on the input voltage P lim And / or the time constant after reduction may be changed depending on the available output voltage.

[0072] <effect> The operation of the vehicle control device configured as above will now be described.

[0073] FIG. 4 shows the comparison example of the engine torque T E , (B) Detected rotation speed value ω g 4A and 4B are graphs showing (A) and (B) input power P to the battery 10. This comparative example is an example in which the time constant of the model matching compensator 41 is set to a reference time constant (Tm) and the time constant of the disturbance observer 42 is set to a reference time constant (Th), regardless of whether or not the input voltage and / or output voltage of the battery 10 is limited. FIG. 4A shows the engine torque T when a disturbance is input to the engine 17 under the condition that the battery 10 is protected (the input voltage and / or output voltage is limited). E , rotation speed detection value ω g , and the input power P. The horizontal axis of each graph in FIG. 4 represents time (for example, seconds).

[0074] When a disturbance occurs in the engine 17 while the battery 10 is being protected, if the characteristics of the model matching compensator 41 and the disturbance observer 42 are not adjusted at all, the input power P from the power generation system 12 to the battery 10 will fluctuate greatly, as shown in Fig. 4(C). Therefore, as shown by the dashed line in Fig. 4(C), the input power P from the power generation system 12 to the battery 10 will fluctuate greatly. lim As a result, the torque-controlled engine 17 may overspeed.

[0075] 5 is a graph showing (A) the engine torque TE, the rotational speed detection value ωg, and the input power P to the battery 10 under the control of the first embodiment. That is, FIG. 5 shows the engine torque T in a state where a disturbance of the engine 17 is input while the battery 10 is being protected, and the time constant of the model matching compensator 41 and the time constant of the disturbance observer 42 are reduced. E , rotation speed detection value ω g , and the input power P. The horizontal axis of each graph in FIG. 5 represents time (for example, seconds).

[0076] When a disturbance occurs in the engine 17 while the battery 10 is being protected, if the responsiveness of the model matching compensator 41 and the disturbance observer 42 is reduced, the oscillation of the input power P from the power generation system 12 to the battery 10 is reduced as shown in FIG. 5(C). Therefore, the oscillation of the input power P from the power generation system 12 to the battery 10 is reduced by the inputtable voltage P of the battery 10. lim Therefore, even if the engine 17 is torque controlled, the engine 17 is prevented from over-revving.

[0077] In the first embodiment, when it is determined that protection of the battery 10 is necessary, the rotation speed control unit 31 reduces the responsiveness of the rotation speed control by reducing both the responsiveness of the model matching compensator 41 and the responsiveness of the disturbance observer 42, but this is not limiting. The rotation speed control unit 31 may reduce the responsiveness of the rotation speed control by reducing either the responsiveness of the model matching compensator 41 or the responsiveness of the disturbance observer 42.

[0078] As described above, the vehicle control method according to this embodiment is a vehicle control method for controlling an electric vehicle 100 having an engine 17 as a power source that generates power, a generator 18 driven by the power, and a battery 10 that is charged by the power generated by the generator 18. In this vehicle control method, a rotation speed detection value ω g The rotation speed of the generator 18 is controlled by a rotation speed control that feeds back the above. Furthermore, the battery controller 23 or the like determines whether or not it is necessary to protect the battery 10 based on the state of the battery 10, i.e., the SOC, etc. When it is determined that protection of the battery 10 is necessary, the responsiveness of the rotation speed control is reduced compared to when protection of the battery 10 is not necessary.

[0079] In this way, in the electric vehicle 100 having the battery 10 charged by the power generated by the generator 18 driven by the engine 17, if the responsiveness of the rotation control is reduced when the protection of the battery 10 becomes necessary, the fluctuation of the power input from the generator 18 to the battery 10 is suppressed. As a result, even if the input voltage to the battery 10 is temporarily reduced, the input voltage P lim As a result, even if the engine 17 constituting the power generation system 12 is controlled by so-called torque control, the engine 17 can be continuously controlled within a range that does not result in overspeeding. Therefore, even in situations where the battery 10 needs to be protected, such as when the battery 10 is in a low temperature state, the power generation system 12 can stably supply power.

[0080] In the vehicle control method according to this embodiment, when protection of the battery 10 is not required or when protection of the battery 10 is no longer required, the responsiveness of the rotation control is set to a high steady-state responsiveness. Therefore, in a situation where protection of the battery 10 is not required, the rotation speed control responds quickly to disturbances of the engine 17, etc. Therefore, in a situation where protection of the battery 10 is not required, fluctuations in the rotation speed of the generator 18 due to disturbances of the engine 17, etc. are appropriately suppressed.

[0081] In the vehicle control method according to the present embodiment, the rotation speed of the generator 18 is controlled based on the rotation speed detection value ω g is fed back via the model matching filter 52, the rotation speed of the generator 18 (i.e., the rotation speed detection value ω g ) is the generator rotation speed command value ω g * and the second torque target value Tω2, which is fed back to suppress disturbances. * using a first disturbance observer filter 56 and a second disturbance observer filter 57. When it is determined that protection of the battery 10 is necessary, the response of the model matching and / or the response of the disturbance observer 42 is reduced.

[0082] In this way, if the response of the model matching and / or the disturbance observer 42 is reduced, in a scene where the battery 10 needs to be protected, the disturbance caused by the engine 17 may affect the rotation state of the generator 18 (detected rotation speed value ω g ) is subject to a sudden change, such a sudden change is smoothed by the model matching compensator 41 and / or the disturbance observer 42. Therefore, in a situation where protection of the battery 10 is required, the final torque command value Tω of the generator 18 is smoothed against a disturbance by the engine 17, etc. * As a result, fluctuations in the power input from the generator 18 to the battery 10 are more easily suppressed.

[0083] In particular, in the vehicle control method according to this embodiment, when it is determined that protection of the battery 10 is necessary, the time constant of the model matching filter 52 is increased to be greater than the reference time constant (Tm) used in steady state, thereby reducing the responsiveness of model matching. This makes model matching less sensitive to disturbances caused by the engine 17 in situations where protection of the battery 10 is necessary. As a result, fluctuations in the power input from the generator 18 to the battery 10 are more easily suppressed.

[0084] Furthermore, in the vehicle control method according to the present embodiment, when it is determined that protection of the battery 10 is necessary, the time constants of the first disturbance observer filter 56 and the second disturbance observer filter 57 are increased to be greater than the reference time constant (Th) used in steady state. That is, when it is determined that protection of the battery 10 is necessary, the time constants of the band-pass filters H(s) constituting the first disturbance observer filter 56 and the second disturbance observer filter 57 are adjusted. This makes the disturbance observer 42 less sensitive to disturbances caused by the engine 17 in a situation where protection of the battery 10 is necessary. As a result, fluctuations in the power input from the generator 18 to the battery 10 are more likely to be suppressed.

[0085] [Second embodiment] In the first embodiment, when it is determined that protection of the battery 10 is necessary, the responsiveness of the rotation speed control of the generator 18 is reduced by adjusting the model matching and / or the time constant of the disturbance observer 42. At this time, with regard to model matching, the first model matching gain gc and the second model matching gain pc are also reduced by reducing the time constant. That is, with regard to model matching, the gain of model matching is also reduced by reducing the time constant. Therefore, with regard to model matching, the reduction of the first model matching gain gc and the second model matching gain pc also contributes to suppressing fluctuations in the input power P to the battery 10.

[0086] On the other hand, since the model matching and the disturbance observer 42 are feedback control systems, there are cases where the feedback gain is set more explicitly. In this case, the fluctuation of the input power P to the battery 10 can also be suppressed by directly reducing the feedback gain of the model matching and / or the disturbance observer 42. In the second embodiment, a configuration etc. for suppressing the fluctuation of the input power P to the battery 10 when a more explicit feedback gain is set in the model matching and the disturbance observer 42 will be described.

[0087] 6 is a block diagram showing the configuration of the rotation speed control unit of the second embodiment. g The feedback path of the second torque target value Tω2 from the disturbance observer 42 to the torque command value calculation unit 43. * The feedback path includes a feedback gain setting unit 60. The same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

[0088] The feedback gain setting unit 60 sets feedback gains for the model matching compensator 41 and the disturbance observer 42. Specifically, the feedback gain setting unit 60 includes a first feedback gain setting unit 61 and a second feedback gain setting unit 62.

[0089] The first feedback gain setting unit 61 sets the rotation speed detection value ω g The first feedback gain setting unit 61 is a multiplier provided in the input path of the rotation speed detection value ω g is multiplied by a first feedback gain fb1, and the result is input to the model matching filter 52.

[0090] The first feedback gain fb1 is set in advance, for example, by adaptation, in order to ensure responsiveness of rotation speed control in a steady state when protection of the battery 10 is not required. The first feedback gain fb1 in a steady state is typically set to a value of 1 or greater. In this embodiment, for simplicity, it is assumed that the first feedback gain fb1 in a steady state is set in advance to "1." In addition, hereinafter, this first feedback gain fb1 in a steady state is referred to as a first reference feedback gain.

[0091] The second feedback gain setting unit 62 sets the second torque target value Tω2 from the disturbance observer 42 to the torque command value calculation unit 43. * The second feedback gain setting unit 62 is a multiplier provided in the input path of the second torque target value Tω2 * is multiplied by a second feedback gain fb2, and the result is input to the torque command value calculation unit 43.

[0092] The second feedback gain fb2 is predetermined, for example, by adaptation, in order to ensure responsiveness of rotation speed control during steady-state operation when protection of the battery 10 is not required. The second feedback gain fb2 during steady-state operation is typically set to a value of 1 or greater. In this embodiment, for simplicity, the second feedback gain fb2 during steady-state operation is assumed to be preset to "1." In addition, hereinafter, this second feedback gain fb2 during steady-state operation is referred to as the second reference feedback gain.

[0093] The configuration of the rotational speed control unit 31 in the second embodiment is as described above. Furthermore, in this embodiment, when it is determined that protection of the battery 10 is necessary, the rotational speed control unit 31 reduces the responsiveness of rotational speed control by adjusting the gain of rotational speed control as compared to when protection of the battery 10 is not necessary.

[0094] For this reason, the feedback gain setting unit 60 is configured such that the battery protection flag FLG is input. Then, the rotational speed control unit 31 reduces the responsiveness of rotational speed control by adjusting the first feedback gain fb1, which is the gain of model matching, and / or the second feedback gain fb2, which is the gain of the disturbance observer 42, according to the battery protection flag FLG. Here, as an example, it is assumed that the rotational speed control unit 31 adjusts both the first feedback gain fb1 and the second feedback gain fb2.

[0095] The first feedback gain fb1, which is the gain of model matching, is adjusted as follows. That is, when it is determined that protection of the battery 10 is necessary, the rotational speed control unit 31 reduces the first feedback gain fb1 below the first reference feedback gain, which is the first feedback gain fb1 in the steady state. In this embodiment, since the first reference feedback gain is "1", when it is determined that protection of the battery 10 is necessary, the rotational speed control unit 31 sets the first feedback gain fb1 to a value within the range of 0 ≦ fb1 < 1, more preferably within the range of 0 < fb1 < 1. As a result, even if a sharp change occurs in the rotational speed detection value ω g due to a disturbance of the engine 17 or the like, such a sharp change is input to the model matching filter 52 in a suppressed state. For this reason, the responsiveness of model matching is reduced with respect to disturbances of the engine 17 or the like.

[0096] The degree of reduction of the first feedback gain fb1, that is, the value of the first feedback gain fb1 after reduction, is determined in advance by adaptation according to, for example, the configuration of the specific power generation system 12. Note that the rotation speed control unit 31 can adjust the value of the first feedback gain fb1 after reduction according to the degree of restriction on the input voltage to the battery 10 and / or the output voltage from the battery 10. For example, the rotation speed control unit 31 may change the value of the first feedback gain fb1 after reduction according to the inputable voltage P lim and / or the outputable voltage of the battery 10.

[0097] The second feedback gain fb2, which is the gain of the disturbance observer 42, is adjusted as follows. That is, when protection of the battery 10 is necessary, the rotation speed control unit 31 reduces the second feedback gain fb2 below the second reference feedback gain, which is the second feedback gain fb2 in the steady state. In the present embodiment, since the second reference feedback gain is "1", when protection of the battery 10 is necessary, the rotation speed control unit 31 sets the second feedback gain fb2 to a value within the range of 0≦fb2<1, more preferably within the range of 0<fb2<1. Thereby, even if a steep change occurs in the rotation speed detection value ω g due to a disturbance or the like of the engine 17, such a steep change is suppressed by the second feedback gain fb2 at the stage where the second torque target value Tω2 * is fed back. For this reason, the responsiveness of the disturbance observer 42 is reduced with respect to disturbances or the like of the engine 17.

[0098] The degree of reduction of the second feedback gain fb2, that is, the value of the second feedback gain fb2 after reduction, is determined in advance by adaptation according to, for example, the configuration of the specific power generation system 12. Note that the rotation speed control unit 31 can adjust the value of the second feedback gain fb2 after reduction according to the degree of restriction on the input voltage to the battery 10 and / or the output voltage from the battery 10. For example, the rotation speed control unit 31 may change the value of the second feedback gain fb2 after reduction according to the inputable voltage P limAnd / or the value of the second feedback gain fb2 after reduction may be changed depending on the available output voltage.

[0099] As described above, in the vehicle control method according to the second embodiment, when it is determined that protection of the battery 10 is necessary, the first feedback gain fb1, which is a gain for model matching, is reduced. g Therefore, in a situation where protection of the battery 10 is required, even if a disturbance of the engine 17 or the like occurs, fluctuations in the input power P to the battery 10 are suppressed.

[0100] In the vehicle control method according to the second embodiment, when it is determined that protection of the battery 10 is necessary, the second feedback gain fb2, which is the gain of the disturbance observer 42, is reduced. As a result, the rotation speed detection value ω g Even if a sudden change occurs in the second torque target value Tω2 * is fed back, such abrupt changes are suppressed. Therefore, in a situation where protection of the battery 10 is required, even if a disturbance of the engine 17 or the like occurs, fluctuations in the input power P to the battery 10 are suppressed.

[0101] The time constant control in the first embodiment and the gain control in the second embodiment can be carried out in part or in whole in combination.

[0102] In the first and second embodiments described above, it is preferable to initialize the disturbance observer 42 when protection of the battery 10 becomes necessary and when protection of the battery 10 becomes unnecessary. The disturbance observer 42 uses a band-pass filter H(s), which actually includes an integrator (low-pass filter). Therefore, by initializing this integrator when protection of the battery 10 becomes necessary and when protection of the battery becomes unnecessary, torque fluctuations caused by switching the time constant and gain of the disturbance observer 42 are suppressed. Note that initialization of the disturbance observer 42 is performed by the rotation speed control unit 31.

[0103] Similarly, in the first and second embodiments, it is preferable to initialize the model matching filter 52 when protection of the battery 10 becomes necessary and when protection of the battery 10 is no longer necessary. The model matching filter 52 has a transfer characteristic H mm Since the model matching filter 52 is a low-pass filter represented by (s), it is essentially an integrator. Therefore, when protection of the battery 10 becomes necessary, and when protection of the battery becomes unnecessary, the model matching filter 52, which is an integrator, is initialized, thereby suppressing torque fluctuations caused by switching the time constant and gain of the model matching. Note that the initialization of the model matching filter 52 is performed by the rotation speed control unit 31.

[0104] In addition, in the first and second embodiments, the inputtable voltage P of the battery 10 is calculated based on the temperature, voltage, current, and / or charging rate of the battery 10. lim And / or calculate the output voltage of the battery 10, and calculate this input voltage P lim It is preferable to determine whether protection of the battery 10 is necessary or not based on the available output voltage P lim and / or the available output voltage is a direct and clear criterion for protecting the battery 10. Therefore, as described above, the available input voltage P limAnd / or if the necessity of protecting the battery 10 is determined based on the available output voltage, the battery 10 can be protected particularly reliably, and the power generation system 12 can supply electric power stably.

[0105] In particular, in the above first and second embodiments, it is preferable that it is determined that the battery 10 needs to be protected when it is necessary to limit the input power to the battery 10 and / or when it is necessary to limit the output power from the battery 10.

[0106] The above describes embodiments of the present invention, but the configurations described in the above embodiments and each modified example only show some of the application examples of the present invention and are not intended to limit the technical scope of the present invention.

[0107] For example, in each of the above embodiments, the power generation system 12 using the engine 17 is the object to be controlled, but the object to be controlled may be a device or system that generates power using a power source other than the engine 17. Also, while the above embodiments exemplify the electric vehicle 100, the present invention can be suitably implemented in vehicles other than the electric vehicle 100, and other devices or systems. Furthermore, the present invention can control a device or system other than the power generation system 12 exemplified in each of the above embodiments, as long as the device or system charges the battery 10 using a generator 18 driven by a power source. [Explanation of symbols]

[0108] 10: Battery, 11: Drive motor, 12: Power generation system, 13: Reducer, 14: Drive shaft, 15: Drive wheel, 16: Drive inverter, 17: Engine, 18: Generator, 20: Generator inverter, 21: System controller, 22: Drive motor controller, 23: Battery controller, 24: Generator controller, 25: Engine controller, 26: Power generation control unit, 31: Rotation speed control unit, 32: Current command value calculation unit, 33: Current control unit, 34: Decoupling control unit, 35: Current converter, 36: Voltage converter, 38: Subtraction unit 39: Subtraction unit, 40: Current sensor, 41: Model matching compensation unit, 42: Disturbance observer, 43: Torque command value calculation unit, 51: First model matching gain multiplication unit, 52: Model matching filter, 53: Subtraction unit, 54: Second model matching gain multiplication unit, 56: First disturbance observer filter, 57: Second disturbance observer filter, 58: Subtraction unit, 60: Feedback gain setting unit, 61: First feedback gain setting unit, 62: Second feedback gain setting unit, 100: Electric vehicle, 101: Power generation system control device

Claims

1. A vehicle control method for controlling a vehicle having a power source that generates power, a generator that is driven by the power source, and a battery that is charged by electric power generated by the generator, comprising: controlling the rotation speed of the generator by a rotation speed control that feeds back the rotation state of the generator; calculating a possible input voltage and / or a possible output voltage of the battery based on the temperature, voltage, current, and / or charging rate of the battery; determining whether protection of the battery is necessary based on the available input voltage and / or the available output voltage; When it is determined that protection of the battery is necessary, the responsiveness of the rotation speed control is reduced compared to when protection of the battery is not necessary. Vehicle control method.

2. 2. The vehicle control method according to claim 1, The rotation speed control is model matching, in which the rotation speed detection value of the generator is fed back via a model matching filter to make the rotation speed follow a rotation speed command value; a disturbance observer that calculates a torque target value to be fed back to suppress disturbances using a disturbance observer filter; By reducing the response of the model matching and / or the response of the disturbance observer when it is determined that protection of the battery is necessary; Vehicle control method.

3. 3. The vehicle control method according to claim 2, increasing the time constant of the model matching filter when it is determined that protection of the battery is necessary; Vehicle control method.

4. 4. A vehicle control method according to claim 2 or 3, increasing the time constant of the disturbance observer filter when it is determined that protection of the battery is necessary; Vehicle control method.

5. The vehicle control method according to any one of claims 2 to 4, reducing a gain of the model matching when it is determined that protection of the battery is necessary; Vehicle control method.

6. The vehicle control method according to any one of claims 2 to 4, reducing a gain of the disturbance observer when it is determined that protection of the battery is necessary; Vehicle control method.

7. The vehicle control method according to any one of claims 2 to 6, initializing the disturbance observer when protection of the battery becomes necessary and when protection of the battery becomes unnecessary; Vehicle control method.

8. 2. The vehicle control method according to claim 1, determining that it is necessary to protect the battery when it is necessary to limit input power to the battery and / or when it is necessary to limit output power from the battery; Vehicle control method.

9. A vehicle control device that controls a vehicle having a power source that generates power, a generator that is driven by the power, and a battery that is charged by electric power generated by the generator, a rotation speed control unit that controls the rotation speed of the generator by feedbacking a rotation state of the generator; a protection necessity determination unit that calculates an allowable input voltage and / or an allowable output voltage of the battery based on the temperature, voltage, current, and / or charging rate of the battery, and determines whether protection of the battery is necessary based on the allowable input voltage and / or the allowable output voltage; Equipped with When it is determined that protection of the battery is necessary, the rotation speed control unit reduces the responsiveness of the rotation speed control compared to when protection of the battery is not necessary. Vehicle control device.

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