Generator control method and generator control device

Abstract

This power generator control method controls a power generator driven by an engine via the crank shaft of the engine and determines whether the engine stops or not. When it is determined that the engine stops, the method operates the power generator to adjust the crank position of the crank shaft to a predetermined target stop position and determines whether or not the cylinder internal pressure of the engine is greater than or equal to a predetermined threshold value. When the cylinder internal pressure is greater than or equal to the threshold value, the method continues the operation of the power generator to maintain the crank position at the target stop position.

Description

[Technical Field]

[0001] The present invention relates to a generator control method and a generator control device. [Background technology]

[0002] JP2018-002107A discloses a vehicle that performs crank position control in which, when the engine stops, an alternator (generator) brakes the crankshaft of the engine to stop the crankshaft at a desired target stop position. In this crank position control, the alternator (generator) is controlled to generate a braking torque on the crankshaft, thereby controlling the crank position. Summary of the Invention

[0003] However, the above-described crank position control has a problem in that the crank position deviates from the target stop position due to a reaction force caused by the internal pressure remaining in the cylinder after the engine is stopped, thereby reducing the accuracy of setting the crankshaft.

[0004] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a generator control method and a generator control device that can more reliably maintain the crank position at a target stop position after the engine has stopped.

[0005] According to one aspect of the present invention, there is provided a generator control method for controlling a generator driven by an engine via the engine crankshaft. The generator control method determines whether the engine will stop, and if it is determined that the engine will stop, operates the generator to adjust the crank position of the crankshaft to a predetermined target stop position. The method also determines whether the engine's internal cylinder pressure is equal to or greater than a predetermined threshold, and if the internal cylinder pressure is equal to or greater than the threshold, continues to operate the generator to maintain the crank position at the target stop position. [Brief explanation of the drawings]

[0006] [Figure 1]FIG. 1 is a block diagram illustrating the main configuration of an electric vehicle in which a generator control method according to each embodiment is executed. [Figure 2] FIG. 2 is a block diagram showing the overall configuration of the generator system. [Figure 3] FIG. 3 is a block diagram showing the configuration of a main part of the generator system according to the first embodiment. [Figure 4] FIG. 4 is a block diagram showing the configuration of a main part of a generator system according to the second embodiment. [Figure 5] FIG. 5 is a block diagram showing the configuration of a main part of a generator system according to the third embodiment. [Figure 6] FIG. 6 is a block diagram showing the configuration of a main part of a generator system according to the fourth embodiment. [Figure 7] FIG. 7 is a timing chart showing the control results of the control of the comparative example. [Figure 8] FIG. 8 is a timing chart showing the control results of the control according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0008] [First embodiment] Fig. 1 is an explanatory diagram showing a schematic configuration of an electric vehicle 100. As shown in Fig. 1, the electric vehicle 100 is a vehicle driven by power from a battery 10, and includes a drive motor 11 and a power generation device 12. In particular, in this embodiment, an example will be described in which the electric vehicle 100 is configured as a so-called series hybrid vehicle.

[0009] 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 device 12. In this embodiment, the battery 10 is a DC power source. The DC voltage (battery voltage V dc) can be detected by a sensor or the like (not shown).

[0010] The drive motor 11 is an electric motor (particularly a three-phase AC motor) that functions as a drive source for propelling the electric vehicle 100. The drive motor 11 is connected to the battery 10 via a drive inverter 16.

[0011] The drive motor 11 (more specifically, the output shaft of the drive motor 11) is connected to the drive wheels 15 via a transmission mechanism such as a reducer 13 and a drive shaft 14. Therefore, during power running (when the electric vehicle 100 is accelerating, etc.), the drive motor 11 receives electric power from the battery 10 and transmits driving force to the drive wheels 15 via the reducer 13, etc. On the other hand, during regenerative running (when the electric vehicle 100 is decelerating, etc.), the drive motor 11 applies regenerative braking force to the drive wheels 15 and regenerates the electric energy obtained by applying the regenerative braking force into the battery 10.

[0012] When the drive motor 11 is in power running mode, the drive inverter 16 converts the DC power output by the battery 10 into AC power and supplies it to the drive motor 11. When the drive motor 11 is in regenerative mode, the drive inverter 16 converts the AC power generated by the drive motor 11 into DC power.

[0013] The engine 17 is a so-called internal combustion engine, and functions as a power source for generating electricity for the power generation device 12. Parameters relating to the operating state of the engine 17, such as the rotation speed of the engine 17, can be detected as appropriate by a sensor or the like (not shown).

[0014] The generator 18 is configured as an electric motor (particularly a three-phase AC motor) that includes a rotor connected to the crankshaft of the engine 17 and a stator on which magnets, windings, etc. are provided. The generator 18 is connected to the battery 10 via a generator inverter 20. During regenerative operation (power generation), the generator 18 applies a regenerative braking force (braking torque) to the crankshaft of the engine 17, and regenerates the electric energy obtained by applying the regenerative braking force into the battery 10.

[0015] The generator inverter 20 converts AC power generated by the generator 18 into DC power when the generator 18 is in regenerative operation. On the other hand, when the generator 18 is in power running operation, the generator inverter 20 converts DC power output by the battery 10 into AC power and supplies it to the generator 18. As a result, when starting the engine 17, the generator 18 is powered to crank the engine 17. Furthermore, depending on the situation, the generator 18 can be powered to idle (motor) the engine 17, thereby consuming the power of the battery 10.

[0016] In the following, the detected value of the current flowing through the U-phase of the generator 18 is referred to as the U-phase current I u , the detected value of the current flowing through the V phase is the V phase current I v , and the detected value of the current flowing through the W phase is the W phase current I w The detected value of the d-axis current of the generator 18 is referred to as the d-axis current I d , and the detected value of the q-axis current is the q-axis current I q 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 It may be collectively referred to as.

[0017] The electric vehicle 100 also includes, as various control devices, 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 also includes a power generation control unit 26.

[0018] The system controller 21 is a higher-level control unit that uses vehicle information to comprehensively control each part of the electric vehicle 100. Here, the vehicle information is parameters that indicate the operating state of each part that constitutes the electric vehicle 100. The vehicle information includes, for example, 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 traveling. The vehicle information can be determined based on detection values ​​of various sensors (not shown), etc.

[0019] The system controller 21 calculates a command value for the output torque of the drive motor 11 (hereinafter simply referred to as the "drive motor torque command value") according to the vehicle information, the SOC (State Of Charge) of the battery 10, the available input power, the available output power, and a target generated power (described later) of the battery 10 input from the battery controller 23. The system controller 21 outputs the calculated drive motor torque command value to the drive motor controller 22.

[0020] Furthermore, the system controller 21 (particularly the power generation control unit 26) calculates the target power generation of the generator 18 based on the vehicle information and the SOC, available input power, and available output power of the battery 10 input from the battery controller 23.

[0021] Furthermore, the power generation control unit 26 controls the operating points of the engine 17 and the generator 18 based on the target generated power. Specifically, the power generation control unit 26 calculates the rotation speed command value ω g * , and the engine torque command value T E * Calculate the following.

[0022] Here, the rotation speed command value ω g * is a command value for the rotation speed (rotational angular velocity) that the generator 18 should maintain in order to generate the target generated power. E * is a command value for the torque that the engine 17 should output in order for the power generation device 12 to achieve the target generated power.

[0023] Then, the power generation control unit 26 calculates the rotation speed command value ω g * and engine torque command value T E * are output to the generator controller 24 and the engine controller 25, respectively.

[0024] 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 .

[0025] The drive motor controller 22 switches the drive inverter 16 on and off in accordance with the state of the drive motor 11, such as the rotation speed and voltage, based on the drive motor torque command value.

[0026] The battery controller 23 refers to the detection values ​​of sensors (not shown) to determine the temperature, voltage, current, internal resistance, SOC, available input power, and available output power of the battery 10. Then, the battery controller 23 outputs the determined SOC, available input power, available output power, etc. to the system controller 21.

[0027] The generator controller 24 controls the operating point of the generator 18. More specifically, the generator controller 24 controls the operating point of the generator 18 based on the rotation speed command value ω g * etc. as inputs to switch the generator inverter 20. In particular, the generator controller 24 of this embodiment uses the detected value of the rotation speed of the generator 18 obtained by the rotation speed sensor 37 (see FIG. 2) (hereinafter simply referred to as the "detected rotation speed value ω g The rotation speed of the generator 18 is controlled by a rotation speed control that feeds back the generator controller 24 (also referred to as "generator controller 24"). The configuration of the generator controller 24 will be described in detail later.

[0028] The engine controller 25 controls the operating point of the engine 17. More specifically, the engine controller 25 controls the operating point of the engine 17 based on the engine torque command value T E *The engine controller 25 operates various actuators (throttle valve, ignition, fuel injector, etc.) of the engine 17 using these as inputs. As a result, the engine 17 operates to achieve the target generated power described above. Furthermore, when the engine controller 25 of this embodiment detects a stop request for the engine 17 (a stop command for the engine 17) in response to an operation by a passenger of the electric vehicle 100 or a command from the system controller 21, the engine controller 25 executes stop processing for the engine 17 (stopping ignition processing, cutting fuel, etc.) and generates an engine stop request flag Enf. Then, the engine controller 25 outputs the engine stop request flag Enf to the generator controller 24 via the system controller 21.

[0029] 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 pieces of computer hardware including a central processing unit (CPU), random access memory (RAM), an input / output interface (I / O interface), etc. Each controller is programmed to execute various controls performed in this embodiment. Note that two or more of these controllers may be configured with one piece of computer hardware.

[0030] The configuration of a system consisting of the generator 18, the generator inverter 20, and the generator controller 24 (hereinafter simply referred to as "generator system S") and the details of each process executed by the generator system S will be described below.

[0031] 2 is a block diagram showing the configuration of the generator system S. As shown in the figure, the generator controller 24, which functions as a control device for the generator system S, includes a control switching determination unit 29, an angle control unit 30, 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.

[0032] The control switching determination unit 29 determines whether the cylinder pressure P engis input, and a control maintain flag Cf is generated to instruct the maintenance or termination of the crank position control. Here, the crank position control in this embodiment refers to control that is started based on the detection of a stop command to the engine 17 (engine stop request flag Enf is on), and that manipulates the operating point of the generator 18 so as to bring the position of the crankshaft (crank position) of the engine 17 closer to a predetermined target stop position.

[0033] Specifically, the control switching determination unit 29 determines whether the cylinder pressure P eng is a predetermined threshold P ength If the value is equal to or greater than the predetermined value, the control maintenance flag Cf is set to ON to command the execution of the crank position control. eng is the threshold P ength If it is less than this, the control maintenance flag Cf is set to OFF.

[0034] Here, the threshold P ength is an appropriate in-cylinder pressure P from the viewpoint of determining whether or not a reaction force is generated to the extent that the crank position is shifted relative to the crankshaft. eng In addition, when the engine 17 is configured with a plurality of cylinders, the control switching determination unit 29 determines the maximum value of the cylinder pressures of the plurality of cylinders as the "cylinder pressure P eng " as the threshold P ength The control switch determination unit 29 then outputs the set control maintenance flag Cf to the control maintenance flag reference unit 44.

[0035] The angle control unit 30 controls the angle command value θ of the generator 18. g * is used as input, and the angle control rotation speed command value ω θg * The angle command value θ g * is a command value for the angle (mechanical angle or electrical angle) of the generator 18 determined according to the target generated power. g * is, for example, the rotation speed command value ω g *The angle control rotation speed command value ω θg * is a command value of the generator rotation speed determined in crank position control according to the difference between the crank position and the target stop position.

[0036] The rotation speed control unit 31 refers to the control maintenance flag Cf and determines the rotation speed command value ω g * and the angle control rotation speed command value ω input from the angle control unit 30 θg * Based on either of the above, the output torque of the generator 18 (hereinafter simply referred to as "generator torque T ω The final torque command value T ω ** The configuration of the rotation speed control unit 31 will be described in detail later.

[0037] The current command value calculation unit 32 calculates the final torque command value T ω ** , the rotation speed detection value ω from the rotation speed sensor 37 g , and the battery voltage V dc is used as an input, and the d-axis current command value I d * and q-axis current command value I q * Then, the current command value calculation unit 32 calculates the calculated d-axis current command value I d * and q-axis current command value I q * is output to the current control unit 33.

[0038] The current control unit 33 calculates 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 *The d-axis voltage command value V d * and q-axis voltage command value V q * The d-axis final voltage command value V' obtained by the subtraction is calculated by subtracting a non-interacting control voltage, which will be described later, from the d-axis final voltage command value V' by subtracting units 38 and 39. d * and the q-axis final voltage command value V' q * is output to the voltage converter 36.

[0039] The decoupling control unit 34 controls the d-axis current I d and q-axis current I q is used to calculate the non-interacting control voltage to reduce the voltage drop due to the interference between the d-axis and q-axis.

[0040] The current transformer 35 converts the three-phase current I u ,I v ,I w The dq axis current I d ,I q Convert to three-phase current I u ,I v ,I w is detected by a current sensor 50 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 Then, as described above, the current converter 35 converts the calculated d-axis current I d ,I q is output to the current command value calculation unit 32 and the non-interference control unit 34.

[0041] 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 *The voltage converter 36 calculates the three-phase voltage command value V u * ,V v * ,V w * is output to the generator inverter 20.

[0042] The generator inverter 20 generates a three-phase voltage command value V u * ,V v * ,V w * is input to each phase of the generator 18, and the U-phase voltage V u , V phase voltage V v , and W-phase voltage V w This causes the generator 18 to operate at the desired operating point.

[0043] The main parts of the generator system S, focusing on the processing in the angle control unit 30 and the rotation speed control unit 31, will be described in further detail below.

[0044] 3 is a block diagram showing the configuration of the main part of the generator system S. As shown in the figure, an angle control unit 30 controls, for example, the angle detection value θ g and angle command value θ g * The deviation from the angle is multiplied by the gain ag to obtain the angle control rotation speed command value ω θg * Calculate the following.

[0045] Here, the detected angle value θ g is the current detected value of the rotation angle (mechanical angle) of the generator 18. g is the rotation speed detection value ω detected by the rotation speed sensor 37 g The angle command value θ g * is determined as the rotation angle of the generator 18 corresponding to the target stop position in the crank position control. g *is defined as the rotation angle of the output shaft of the generator 18 connected to the crankshaft when the crankshaft is positioned at the target stop position.

[0046] On the other hand, the rotation speed control unit 31 includes a stop command flag reference unit 40, a model matching compensation unit 41, and a disturbance observer .

[0047] The stop command flag reference unit 40 refers to the engine stop request flag Enf and calculates the rotation speed command value ω g * and angle control rotation speed command value ω θg * or the like to the model matching compensation unit 41. More specifically, when the engine stop request flag Enf is off, the stop command flag reference unit 40 outputs either of the rotation speed command value ω g * (a command value determined according to the target power generation), and when the engine stop request flag Enf is on, the angle control rotation speed command value ω θg * (command value for crank position control). For the sake of simplicity, the following explanation of each process will be given using the angle control rotation speed command value ω for crank position control. θg * This section focuses on the case where

[0048] The model matching compensation unit 41 uses, for example, PI control to calculate the rotation speed detection value ω g The angle control rotation speed command value ω θg * The first torque target value T ω1 * In particular, 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 .

[0049] The first model matching gain multiplication unit 51 multiplies the angle control rotation speed command value ω θg *is multiplied by a first model matching gain gc. The first model matching gain gc is calculated by multiplying the design value J' of the total inertia J of the generator 18 and the engine 17 converted to the generator shaft, the design value C' of the viscous friction coefficient, and the time constant T of the target response. m Using this, it is expressed by the following equation (1).

[0050]

number

[0051] 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. m In principle, it is preferable that is determined so that the model matching compensator 41 responds as quickly as possible within the limits that do not impair control stability.

[0052] 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.

[0053]

number

[0054] The subtractor 53 subtracts the 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.

[0055] 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).

[0056]

number

[0057] The model matching compensation unit 41 multiplies the output of the second model matching gain multiplication unit 54 by the first torque target value T ω1 * The first torque target value T ω1 * is the generator torque T determined by model matching as described above. ω This is the target value.

[0058] The disturbance observer 42 calculates the basic torque command value T ω * and rotation speed detection value ω g is input, and a second torque target value T corresponding to a disturbance torque estimate value according to a control system model of the engine 17 and the generator 18 is calculated. ω2 * Calculate the following.

[0059] The basic torque command value T ω * is the torque disturbance T during crank position control. d The generator torque T is determined from the viewpoint of approaching the crank position to the target stop position while taking into account the influence of ω is the basic command value of the disturbance torque T d is the input torque component from the engine 17 (more specifically, the crankshaft) to the generator 18, which is caused by factors such as the compression reaction force of the engine 17, combustion torque pulsation, and abnormal combustion. That is, the disturbance torque T d is the cylinder pressure P of the engine 17 eng is strongly correlated with

[0060] In particular, 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 .

[0061] The first disturbance observer filter 56 calculates the basic torque command value T ω * The second torque target value T ω2* The first term (first element) that constitutes T ω2a * Calculate the following.

[0062]

number

[0063] In addition, "T h " is the time constant of the disturbance observer 42, which is determined appropriately. That is, the first term T ω2a * is the basic torque command value T ω * This corresponds to an actual torque estimate that does not include disturbance components and is obtained based on

[0064] The second disturbance observer filter 57 detects the rotation speed ω g The second torque target value T ω2 * The second term (second element) that constitutes T ω2b * The transfer characteristic Gp'(s) is a model of the transfer characteristic from torque input to rotation speed in the generator system S, and is expressed by the following equation (5).

[0065]

number

[0066] That is, the second term T ω2b *is the rotation speed detection value ω g This corresponds to an estimated actual torque value including disturbance components, which is obtained by inversely calculating the rotation speed from the torque input.

[0067] The subtractor 58 subtracts the first term T ω2a * From the second term T ω2b * The second torque target value T ω2 * The subtraction unit 58 calculates the calculated second torque target value T ω2 * is output to the torque command value calculation unit 43.

[0068] The torque command value calculation unit 43 calculates the first torque target value T ω1 * The second torque target value T ω2 * is fed back to obtain the basic torque command value T ω * In this embodiment, the torque command value calculation unit 43 is a subtractor, and calculates the first torque target value T ω1 * to the second torque target value T ω2 * By subtracting the basic torque command value T ω * Furthermore, the torque command value calculation unit 43 calculates the calculated basic torque command value T ω * is output to the control maintenance flag reference unit 44.

[0069] The control maintenance flag reference unit 44 refers to the control maintenance flag Cf from the control switching determination unit 29 and determines the basic torque command value T ω * More specifically, when the control maintenance flag Cf is on (when the in-cylinder pressure P eng is the threshold P ength If the torque command value is greater than or equal to the basic torque command value T ω * is output, and if the control maintenance flag Cf is off (cylinder pressure Peng is the threshold P ength If the value is less than 0, it outputs 0.

[0070] The adder 45 adds the disturbance torque T d This is a construct to express the influence of

[0071] The controlled object α refers to all control elements in the generator system S from the rotation speed control unit 31 onwards, namely, the current command value calculation unit 32, the current control unit 33, the non-interference control unit 34, the current converter 35, the voltage converter 36, the generator inverter 20, and the generator 18.

[0072] In particular, the controlled object α can be expressed by the transfer function of the following equation (6) using the total inertia J of the generator 18 and the engine 17 converted to the generator shaft and the viscous friction coefficient C.

[0073]

number

[0074] Furthermore, the rotation speed detection value ω output from the controlled object α g The disturbance rotation speed ω is detected / estimated by a detection / estimation device (not shown). d is added, and the value after addition is fed back to the model matching compensation unit 41. Furthermore, this rotation speed detection value ω g The detected angle value θ is obtained by integrating g is fed back to the angle control unit 30.

[0075] According to the above-mentioned control logic, the cylinder pressure P eng is the threshold P ength If it is equal to or greater than this, the final torque command value T ω ** (Generator torque T ω ) is the detected angle value θ g The angle command value θ g * The angle control rotation speed command value ω is determined by the deviation of θg *The basic torque command value T ω * and disturbance torque T d Therefore, the generator 18 operates to move the crank position closer to the target stop position. In particular, in this case, when the crank position reaches the target stop position, (θ g =θ g * The basic torque command value T ω * becomes zero, the generator torque T ω is the remaining cylinder pressure P eng Disturbance torque T according to d continues to be output (crank position control is maintained).

[0076] On the other hand, the cylinder pressure P eng is the threshold P ength If the generator torque T ω is the disturbance torque T d Therefore, when the crank position reaches the target stop position, the cylinder pressure P eng When the torque drops below a certain level, the disturbance torque T d (Generator torque T ω ) becomes almost zero, and the crank position control ends.

[0077] The configuration and effects of the generator control method according to the present embodiment will now be described.

[0078] In this embodiment, a generator control method is provided for controlling the generator 18 driven by the engine 17 via the crankshaft of the engine 17. In this generator control method, it is determined whether the engine 17 will stop, and if it is determined that the engine 17 will stop (if the engine stop request flag Enf is on), the generator 18 is operated to adjust the crank position of the crankshaft to a predetermined target stop position. Also, the in-cylinder pressure P eng is a predetermined threshold P ength It is determined whether or not the in-cylinder pressure P eng is the threshold P engthIf so, the operation of the generator 18 continues to maintain the crank position at the target stop position.

[0079] As a result, the cylinder pressure P eng is higher than a certain level, the operation of the generator 18 (crank position control) continues so as to maintain the crank position at the target stop position even after the crank position reaches the target stop position. This makes it possible to suppress deviation of the crank position due to pressure remaining in the cylinder after the engine 17 is stopped. In other words, it is possible to more reliably maintain the crank position at the target stop position after the engine is stopped.

[0080] In the present embodiment, an example has been described in which the generator controller 24 determines whether or not the engine 17 is to be stopped by referring to the engine stop request flag Enf generated by the engine controller 25. However, this is not limiting, and the generator controller 24 itself may employ logic for determining whether or not the engine 17 is to be stopped by referring to the detected values ​​of the rotation speeds of the generator 18 and / or the engine 17.

[0081] In this embodiment, the disturbance torque T d and calculates the basic torque command value T of the generator 18 based on the difference between the crank position and the target stop position. ω * (the model matching compensation unit 41 and the torque command value calculation unit 43). eng is the threshold P ength If it is equal to or greater than the basic torque command value T ω * and disturbance torque T d The generator torque T as the output torque of the generator 18 based on ω is determined (control maintenance flag reference unit 44 and adder 45).

[0082] As a result, the cylinder pressure P eng When the crank position is higher than a certain level, the generator torque T ωOn the other hand, even if the crank position reaches the target stop position (basic torque command value T ω * becomes zero), the generator torque T ω The input disturbance torque T d The crank position can be maintained at the target stop position by adjusting the cylinder pressure P eng is the threshold P ength If so, more specific control logic is implemented to maintain the crank position at the target stop position.

[0083] Furthermore, in this embodiment, the crank position is calculated based on the rotation angle detection value of the generator 18 (detected angle value θ g ) and the rotation angle command value (angle command value θ g * Then, the difference between the crank position and the target stop position is calculated as the angle detection value θ g and angle command value θ g * The angle control unit 30 determines the deviation from the angle.

[0084] This allows the crank position control to be performed using the parameters in the control system of the generator 18. That is, the parameter corresponding to the crank position in the control system of the engine 17 (crank angle θ e Therefore, a control logic is realized that can execute crank position control without using any detected values ​​of the torque converter.

[0085] In this embodiment, the detected angle value θ g The angle command value θ g * The first torque target value T of the generator 18 is set to follow the ω1 * (the angle control unit 30 and the model matching compensation unit 41). Furthermore, the rotation speed detection value ω g is processed by the disturbance observer 42, the second torque target value T ω2 * is calculated (disturbance observer 42).

[0086] And the cylinder pressure P eng is the threshold P ength If this is the case, the generator torque T ω The basic torque command value T ω * On the other hand, the cylinder pressure P eng is the threshold P ength If the generator torque T ω Disturbance torque T d (control maintenance flag reference unit 44).

[0087] As a result, the cylinder pressure P eng When the crank position is adjusted to the target stop position, the cylinder pressure P eng In a scene where the value of the rotational speed is equal to or less than a certain value, a more specific control logic is implemented to appropriately complete the crank position control.

[0088] Furthermore, in this embodiment, a generator controller 24 is provided that functions as a generator control device suitable for executing the above-described generator control method.

[0089] The generator controller 24 includes a stop determination unit that determines whether the engine 17 is to be stopped or not, a control unit (41, 42, 43, 45) that operates the generator 18 to adjust the crank position of the crankshaft to a predetermined target stop position when it is determined that the engine 17 is to be stopped (when the engine stop request flag Enf is on), and a control unit (42, 43, 45) that adjusts the in-cylinder pressure P of the engine 17. eng is a predetermined threshold P ength a cylinder pressure determination unit (control maintenance flag reference unit 44) that determines whether the cylinder pressure P eng is the threshold P ength If the condition is equal to or greater than the target stop position, the control maintaining unit (adder 45) continues to operate the generator 18 to maintain the crank position at the target stop position.

[0090] [Second embodiment] The second embodiment will be described below, with the same elements as those in the first embodiment being given the same reference numerals and their description omitted.

[0091] 4 is a block diagram showing the configuration of the main part of the generator system S in this embodiment. As shown in the figure, the generator system S in this embodiment uses the cylinder pressure P eng The cylinder pressure measuring device 60 is provided to estimate the pressure.

[0092] In particular, the in-cylinder pressure measuring device 60 receives the second torque target value T ω2 * and obtain the second torque target value T ω2 * to cylinder pressure P eng That is, the second torque target value T ω2 * is the disturbance torque T input to the generator 18 d is the estimated value of the cylinder pressure P eng (More specifically, the reaction force input from the engine 17 to the generator 18 via the crankshaft). For this reason, the second torque target value T ω2 * to cylinder pressure P eng can be estimated.

[0093] The in-cylinder pressure P estimated by the in-cylinder pressure measuring device 60 eng The control maintenance flag reference unit 44 executes the process using the above formula in the same manner as in the first embodiment.

[0094] As described above, in the generator control method of this embodiment, the in-cylinder pressure P eng The second torque target value T ω2 * Estimate based on.

[0095] As a result, the cylinder pressure P eng Even if it is not possible to directly measure the second torque target value T ω2 * Using the cylinder pressure P engand executes the control after the control maintenance flag reference unit 44.

[0096] [Third embodiment] The third embodiment will be described below, with the same elements as those in the first or second embodiment being given the same reference numerals and their description being omitted.

[0097] 5 is a block diagram showing the configuration of the main part of the generator system S in this embodiment. As shown in the figure, the generator system S in this embodiment also uses the cylinder pressure P eng The cylinder pressure measuring device 60 is provided to estimate the pressure.

[0098] On the other hand, the in-cylinder pressure measuring device 60 of this embodiment measures the torsional torque T to and twist angle θ to is input, and the cylinder pressure P eng Estimate the torsional torque T to is a torque corresponding to the torsional load between the output shaft (rotor) of the generator 18 and the crankshaft of the engine 17. Also, the torsional angle θ to corresponds to the torsional displacement between the output shaft and crankshaft of the generator 18.

[0099] The cylinder pressure measuring device 60 measures the torsional torque T to and twist angle θ to With only one of these as input, the cylinder pressure P eng It is also possible to employ a configuration for estimating the above.

[0100] According to the configuration of this embodiment, the in-cylinder pressure P eng One embodiment of a specific means for estimating is realized.

[0101] [Fourth embodiment] The fourth embodiment will be described below, with the same elements as those in any of the first to third embodiments being given the same reference numerals, and the description thereof will be omitted.

[0102] 6 is a block diagram showing the configuration of the main part of the generator system S in this embodiment. As shown in the figure, the generator system S in this embodiment also controls the cylinder pressure P eng The cylinder pressure measuring device 60 is provided to estimate the pressure.

[0103] On the other hand, the in-cylinder pressure measuring device 60 of this embodiment is configured to measure the crank angle θ of the engine 17. e and crank angular velocity ω e is input, and the cylinder pressure P eng This estimates the cylinder pressure P eng One embodiment of a specific means for estimating is realized.

[0104] The cylinder pressure measuring device 60 detects the crank angle θ e and crank angular velocity ω e With only one of these as input, the cylinder pressure P eng It is also possible to employ a configuration for estimating the above.

[0105] According to the configuration of this embodiment, the in-cylinder pressure P eng One embodiment of a specific means for estimating is realized.

[0106] [Modification of the fourth embodiment] In this modification, the control switching determination unit 29 determines the crank angular velocity ω obtained from the in-cylinder pressure measuring device 60. e is the predetermined value ω eth If the following condition continues for a predetermined time Δt or more, the control maintenance flag Cf is set to ON (cylinder internal pressure P eng is the threshold P ength If not, the control maintenance flag Cf is set to OFF (the cylinder pressure P eng is the threshold P ength (Consider it to be more than that.)

[0107] In addition, the predetermined value ω eth is the cylinder pressure P eng is the threshold P ength The crank angular velocity ω when eIn reality, the predetermined time Δt is determined by an experiment or the like as a value of the in-cylinder pressure P eng is the threshold P ength Despite the above, any factor may temporarily cause the crank angular velocity ω e is the predetermined value ω eth It is set to an appropriate value to eliminate the following situations:

[0108] As described above, in the generator control method of this modified example, the crank angular velocity ω e and a predetermined value ω eth Based on the comparison between the cylinder pressure P eng is the threshold P ength In particular, it is determined whether the crank angular velocity ω e is the predetermined value ω eth If the state where the pressure is equal to or greater than this is less than the predetermined time Δt, the in-cylinder pressure P eng is the threshold P ength It is determined that this is the case.

[0109] As a result, the cylinder pressure P of the engine 17 eng Even though the crank angular velocity ω e is the predetermined value ω eth The cylinder pressure P eng Therefore, it is possible to more reliably avoid a situation in which the crank position control is terminated due to the determination that the crank position is low.

[0110] [Control results] Below, the control results (examples) according to each embodiment will be explained while being compared with the control results according to a comparative example.

[0111] (Comparative Example) 7 is a timing chart illustrating the control results of the comparative example. In the control of the comparative example, the cylinder pressure P eng Regardless of the level of the crank angle θ e ) is the target stop position (target crank angle θ e *) (time t2), the crank position control is ended.

[0112] As shown in the figure, in the control of the comparative example, before time t1, the generator 18 has a rotation speed equal to the rotation speed command value ω g * On the other hand, after time t1, crank position control is started, and the generator 18 operates to follow the crank angle θ e is the target crank angle θ e * (detected angle value θ of generator 18) g is the angle command value θ g * Then, at time t2, the crank angle θ e is the target crank angle θ e * When the crank position control is completed, the crank position control is completed. eng Therefore, even after the crank position control is completed, the remaining in-cylinder pressure P eng The crank angle θ e The target crank angle θ e * This causes deviations and settling errors.

[0113] (Example) 8 is a timing chart illustrating the control results of the embodiment. As shown in the figure, in the control of the embodiment, the crank angle θ e is the target crank angle θ e * Even if the cylinder pressure P eng If the in-cylinder pressure P eng The crank position control ends at time t2 when the crank angle θ e More accurately target crank angle θ e * is held in

[0114] 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.

[0115] For example, in each of the above embodiments, a generator control method has been described that is executed by the generator system S mounted on the electric vehicle 100. However, the generator control method according to the present invention can be similarly executed by employing the generator system S in a vehicle other than the electric vehicle 100 or in other devices.

Claims

1. A generator control method for controlling a generator driven by an engine via a crankshaft of the engine, comprising: determining whether the engine is stopped; When it is determined that the engine is to stop, the generator is operated to adjust the crank position of the crankshaft to a predetermined target stop position; determining whether the in-cylinder pressure of the engine is equal to or greater than a predetermined threshold; If the in-cylinder pressure is equal to or greater than the threshold value, the operation of the generator is continued to maintain the crank position at the target stop position; obtaining a disturbance torque corresponding to a disturbance input to the generator; calculating a basic torque command value for the generator based on a difference between the crank position and the target stop position; When the in-cylinder pressure is equal to or greater than the threshold value, an output torque of the generator is determined based on the basic torque command value and the disturbance torque; the crank position is estimated from a detected value of a rotation angle of the generator; determining a rotation angle command value of the generator according to the target stop position; a difference between the crank position and the target stop position is determined as a deviation between the rotation angle detection value and the rotation angle command value; Generator control method.

2. 2. The generator control method according to claim 1, calculating a first torque target value of the generator so that the rotation angle detection value follows the rotation angle command value; calculating a second torque target value as a disturbance torque estimation value according to a control system model by processing the rotation speed detection value of the generator using a disturbance observer filter; calculating the basic torque command value by subtracting the second torque target value from the first torque target value; When the in-cylinder pressure is equal to or greater than the threshold value, the output torque of the generator is set to the basic torque command value; When the in-cylinder pressure is less than the threshold value, the output torque of the generator is set to be equal to the disturbance torque. Generator control method.

3. 3. The generator control method according to claim 2, The in-cylinder pressure is estimated based on the second torque target value. Generator control method.

4. 3. The generator control method according to claim 1 or 2, The in-cylinder pressure is estimated based on a torsional torque and / or a torsional angle in a power transmission system between the crankshaft and the generator. Generator control method.

5. 3. The generator control method according to claim 1 or 2, The in-cylinder pressure is estimated based on a crank angle and / or a crank angular velocity of the crankshaft. Generator control method.

6. 6. The generator control method according to claim 5, determining whether the in-cylinder pressure is equal to or greater than the threshold value based on a comparison between the crank angular velocity and a predetermined value; If the crank angular velocity remains equal to or greater than the predetermined value for less than a predetermined time, it is determined that the in-cylinder pressure is equal to or greater than the threshold value. Generator control method.

7. A generator control device that controls a generator driven by an engine via a crankshaft of the engine, a stop determination unit that determines whether the engine is stopped; a control unit that, when determining that the engine is to stop, operates the generator to adjust the crank position of the crankshaft to a predetermined target stop position; an in-cylinder pressure determination unit that determines whether an in-cylinder pressure of the engine is equal to or greater than a predetermined threshold; a control maintaining unit that continues operation of the generator to maintain the crank position at the target stop position when the in-cylinder pressure is equal to or greater than the threshold value, The control unit obtaining a disturbance torque corresponding to a disturbance input to the generator; calculating a basic torque command value for the generator based on a difference between the crank position and the target stop position; When the in-cylinder pressure is equal to or greater than the threshold value, an output torque of the generator is determined based on the basic torque command value and the disturbance torque; the crank position is estimated from a detected value of a rotation angle of the generator; determining a rotation angle command value of the generator according to the target stop position; a difference between the crank position and the target stop position is determined as a deviation between the rotation angle detection value and the rotation angle command value; Generator control device.

Images