Switching control method and switching control device

Abstract

Provided is a vehicle equipped with a traveling drive motor operated by a power generator and the generated power of the power generator, wherein: a control mode of a carrier frequency used for a PWM control for adjusting the power of the power generator is set to either a basic mode or a diffusion mode; a noise recognition-degree suggestive amount is obtained that suggests a vehicle status correlating with the high / low degree of vehicle user recognition of noise occurring in the operation of the power generator; and the diffusion mode is executed when estimating, on the basis of the noise recognition-degree suggestive amount, that the recognition degree is high and the basic mode is executed when estimating that the recognition degree is low.

Description

[Technical field]

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

[0002] JP2021-136738A discloses one aspect of PWM (Pulse Width Modulation) control for an inverter as a switching device that adjusts the power supplied to a three-phase AC motor.

[0003] In particular, JP2021-136738A proposes switching control that switches the control mode of the carrier frequency used for PWM control between a diffusion mode in which the carrier frequency is changed (diffused) at a predetermined period, and a basic mode in which the carrier frequency is fixed to a predetermined basic period, depending on the operating point (torque, rotation speed, etc.) set in each of the powering state and regenerative state of the drive motor used to drive the vehicle.

[0004] By setting the control mode to the diffusion mode, noise caused by an increase in the ripple current of the inverter is suppressed. On the other hand, by setting the control mode to the basic mode, switching losses are reduced and optimal energy efficiency is ensured. In other words, in JP2021-136738A, scenes in which noise suppression should be prioritized and scenes in which energy efficiency should be prioritized are distinguished according to the operating point of the drive motor, and an appropriate switching control mode is set for each scene. Summary of the Invention

[0005] In recent years, vehicles (so-called series hybrid vehicles) that use the power generated by a generator to drive the drive motor have become widespread. In this type of vehicle, noise is also generated by the operation of the generator, so it is desirable to set the control mode to a diffusion mode in order to appropriately suppress the noise. However, the operating point of the generator is basically determined independently of the running state of the vehicle. For this reason, even if the operating point of the generator is referred to, it is difficult to appropriately determine a scene in which the noise of the generator is a problem (for example, a scene in which the background noise during running is small). In other words, in the above-mentioned conventional control, when assuming switching control in a series hybrid vehicle equipped with the above-mentioned generator, there is a problem that it is not possible to realize appropriate switching between the basic mode and the diffusion mode according to the scene.

[0006] Therefore, an object of the present invention is to provide a switching control method and a switching control device that can realize appropriate switching between the diffusion mode and the fundamental mode even when applied to the above-mentioned series hybrid vehicle.

[0007] According to one aspect of the present invention, there is provided a switching control method for adjusting the carrier frequency of a carrier wave used in PWM control for adjusting the power of a generator in a vehicle equipped with a generator and a drive motor for running the vehicle operated by the generated power of the generator. In this switching control method, either a basic mode in which the carrier frequency is maintained at a predetermined basic value or a spread mode in which the carrier frequency is changed at a predetermined switching period is set as the control mode of the carrier wave.

[0008] Then, a noise awareness suggestion amount is obtained, which suggests a vehicle condition that correlates with the level of awareness of the vehicle user to the noise generated by the operation of the generator. If the awareness is estimated to be high based on the noise awareness suggestion amount, the diffusion mode is executed, and if the awareness is estimated to be low, the basic mode is executed. [Brief description of the drawings]

[0009] [Figure 1]FIG. 1 is a diagram illustrating a vehicle control system in which a switching control method according to an embodiment of the present invention is executed. [Diagram 2] FIG. 2 is a diagram for explaining an example of a setting mode of the carrier frequency in the spread mode. [Diagram 3] FIG. 3 is a flowchart illustrating the execution decision process in the first embodiment. [Figure 4A] FIG. 4A is a diagram illustrating the correlation between the likelihood of a vehicle user getting off when the vehicle is stopped and the level of the vehicle user's awareness of noise. [Figure 4B] FIG. 4B is a diagram illustrating the correlation between the open / closed state of a vehicle window and the level of noise recognition by a vehicle user. [Diagram 5] FIG. 5 is a flowchart illustrating the execution decision process in the second embodiment. [Figure 6] FIG. 6 is a diagram for explaining the correlation between the open / closed state of the engine hood and the level of noise recognition by vehicle users. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0011] [First embodiment] 1 is a diagram illustrating the configuration of a vehicle control system 100 in which a switching control method according to the present embodiment is executed. The vehicle control system 100 according to the present embodiment is assumed to be applied to a hybrid vehicle (for example, a series hybrid vehicle) equipped with a first electric motor (generator 10) for generating electricity driven by a predetermined drive source (engine 20) and a second electric motor (driving motor 12) for running that operates with the generated power of the first electric motor.

[0012] As shown in the figure, the vehicle control system 100 is mainly composed of a generator 10, a drive motor 12, an inverter 13, a battery 18, an engine 20, and a controller 50. In particular, in the vehicle control system 100 shown in the figure, the generator 10, the drive motor 12, and the inverter 13 are integrated to form an electric motor unit MU.

[0013] The generator 10 is configured with a three-phase AC motor that functions as the first electric motor. In particular, under the control of the inverter 13, the generator 10 receives driving force generated by the engine 20 to generate electric power for driving the drive motor 12, and supplies the generated electric power to the battery 18 or the drive motor 12. The generator 10 may be configured to receive electric power from the battery 18 as appropriate to drive the engine 20. This makes it possible to use the generator 10 to perform cranking (motoring), for example, when starting the engine 20.

[0014] The drive motor 12 is composed of a three-phase AC motor that functions as the second electric motor. In particular, the drive motor 12 operates (power running or regenerative operation) under the control of the inverter 13 by receiving power from the battery 18 or the generator 10 to achieve a desired drive force (braking force), and applies the drive force (braking force) to the drive wheels of the vehicle via a predetermined speed change mechanism (not shown).

[0015] The inverter 13 includes a first switching device 14 , a second switching device 16 , and a smoothing capacitor 22 .

[0016] The first switching device 14 is driven by a PWM signal S input from the controller 50. PWM1 In response to the PWM signal S, the first switching device 14 adjusts the power between the battery 18 and the generator 10 (particularly, converts between DC and AC). PWM1 and a control unit for operating each switching element in a switching pattern corresponding to the switching element.

[0017] The second switching device 16 is driven by a PWM signal S input from the controller 50. PWM2 In response to the PWM signal S, the second switching device 16 adjusts the power between the battery 18 and the drive motor 12 (particularly, converts between DC and AC). PWM2 and a control unit for operating each switching element in a switching pattern corresponding to the switching element.

[0018] The smoothing capacitor 22 smoothes a ripple current that may occur due to the operation of the first switching device 14 or the second switching device 16. In other words, the smoothing capacitor 22 functions as a common capacitive element for the first switching device 14 and the second switching device 16.

[0019] The battery 18 is an in-vehicle DC power supply constituted by a lithium ion secondary battery or the like.

[0020] The engine 20 is connected to the generator 10 via mechanical elements such as gears (not shown), and transmits power for generating electricity to the generator 10. In other words, the engine 20 is used as a drive source for generating electricity by the generator 10. The engine 20 is controlled by the controller 50 to generate a required generated electric power P g_r The operating point (engine torque T e and engine speed N e ) works.

[0021] Next, the configuration of the controller 50 will be described. The controller 50 is configured by a computer that includes a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), and an input / output interface (I / O interface) and is programmed to be able to execute each process described below. The controller 50 can also be configured by multiple computer hardware that executes each process in a distributed manner.

[0022] In particular, the controller 50 determines the desired required power generation P g_rIn response to this, the generator torque T g and rotation speed N g The required power generation P g_r is set to an appropriate value based on the remaining battery charge and other vehicle conditions (such as a request for suppressing noise and vibration, or a request for warming up the catalyst of the engine 20). f_r In response to this, the driving motor torque T d and rotation speed N d The required driving force D f_r is determined based on the amount of operation of an accelerator pedal (accelerator opening) mounted on the vehicle, or a command from a higher-level controller such as an automatic driving control device (not shown).

[0023] Here, the controller 50 determines the operating point (T d ,N d ) based on the PWM signal S PWM2 The carrier frequency f used to generate the carrier c2 (generally several kHz to several tens of kHz). More specifically, the controller 50 adjusts the operating point (T d ,N d ), we identify the scenes where noise suppression should be prioritized and the scenes where switching efficiency should be prioritized, and set the carrier frequency f c2 For example, the controller 50 adjusts the driving point (T d ,N d ) (such as at low engine speeds where background noise is small while driving), the carrier frequency f c2 is changed to reduce the sound vibration (diffusion mode), otherwise the carrier frequency f c2 is fixed to improve switching efficiency (basic mode).

[0024] On the other hand, the controller 50 outputs a PWM signal S related to the control of the generator 10 (switching control of the first switching device 14). PWM1The carrier frequency f used to generate the carrier c1 Set the control mode to adjust the frequency (generally several kHz to several tens of kHz).

[0025] In particular, the controller 50 of this embodiment performs a process (hereinafter also referred to as an "execution decision process") for determining whether the control mode of the first switching device 14 should be set to the diffusion mode or the basic mode, using a noise awareness suggestion amount described below as an input. More specifically, the controller 50 estimates whether the vehicle user O (particularly, the vehicle occupant) has a high or low awareness of the noise caused by the operation of the generator 10 based on the noise awareness suggestion amount, and determines the final control mode according to the estimation result.

[0026] Here, the noise awareness suggestion amount is a parameter indicating a vehicle condition that correlates with the degree of awareness of the vehicle user O to the noise of the generator 10, particularly the degree of awareness by hearing (degree of audibility). in or the surrounding area outside the vehicle (hereinafter, "exterior area C out This is a parameter that specifies the vehicle conditions (such as the presence or absence of noise obstructions, whether the vehicle is stopped for a certain period of time, etc.) that affect the audibility of the noise associated with the operation of the generator 10 to a vehicle user O located at a vehicle position (also referred to as "pedestrian crossing")

[0027] In particular, the noise perception suggestion amount in this embodiment includes a vehicle alighting possibility parameter that suggests the possibility that the vehicle user O will alight when the vehicle is stopped, a vehicle interior C in Background noise parameters that indicate the volume of background noise (driving noise, wind noise, etc.) in the vehicle interior, and cabin C in The first shielding parameter indicates the level of shielding (presence or absence of a physical barrier) against noise transmission between the inside of the vehicle and the noise source (motor unit MU).

[0028] More specifically, the controller 50 receives the shift position signal S sh and pb status signal S pbis the above-mentioned alighting possibility parameter, the vehicle speed v detected or estimated by sensors (not shown) is the above-mentioned background noise parameter, and the opening / closing state signal S win is taken as the first occlusion parameter.

[0029] In addition, the shift position signal S sh is a signal indicating the shift position selected in the vehicle, and is generated based on the detection value of a shift position sensor (not shown). pb is a signal indicating the on / off state of the parking brake, and is generated based on the detection value of a parking brake sensor (not shown). win is a signal indicating the open / closed state of a vehicle window, and is generated based on a window position calculation value calculated from a detection value of a sensor (not shown) or a current of a power window motor.

[0030] In this embodiment, the term "high awareness of noise caused by the operation of the generator 10" refers to a state in which the vehicle interior C in Or outside the vehicle area C out "Low awareness of noise caused by the operation of the generator 10" means a state in which the vehicle user O recognizes the noise stronger than a certain standard (a state in which the user feels an unacceptable discomfort from the noise). On the other hand, "low awareness of noise caused by the operation of the generator 10" means a state in which the vehicle user O recognizes the noise weaker than a certain standard (a state in which the user cannot recognize the noise, or recognizes the noise but does not feel discomfort). In particular, the criteria for distinguishing between high and low awareness levels may be, for example, sensitivity evaluations by multiple vehicle users O, or the vehicle cabin C. in Or outside the vehicle area C out The noise level can be determined quantitatively or qualitatively as appropriate by experiments or simulations based on the analysis results of the relative magnitude of the noise components originating from the generator 10 to all sound components (including background noise, etc.) in the room.

[0031] Then, the controller 50 executes either the basic mode or the spread mode determined based on the result of the execution decision process, and outputs the PWM signal S PWM1 Generate.

[0032] More specifically, the controller 50 selects a carrier frequency f according to the control mode determined by the execution determination process. c1 and the operating point of the generator 10 (T g ,N g ) The voltage command value V g * Based on the comparison result of and, the PWM signal S PWM1 On the other hand, the controller 50 generates the above-mentioned operating point (T d ,N d ) depending on the carrier frequency f c2 The carrier wave and the operating point (T d ,N d ) The voltage command value V d * Based on the comparison result of and, the PWM signal S PWM2 Generate.

[0033] More specifically, the controller 50 determines a voltage command value (V g * ,V d * ) and the carrier wave, and outputs an OFF signal (or ON signal) when the instantaneous value of the carrier wave is equal to or greater than the voltage command value, and outputs an ON signal (or OFF signal) when the instantaneous value falls below the voltage command value. This is repeated to generate a PWM signal (S PWM1 ,S PWM2 )

[0034] In particular, in the fundamental mode, the carrier frequency (f c1 ,f c2 ) to the voltage command value (V g * ,V d * The fundamental frequency F0 is set (fixed) to twice the control period t of the carrier frequency (f c1 ,f c2 By fixing the carrier frequency (f c1 ,f c2In the basic mode, which sets the ripple current at a certain frequency, the ripple voltage level at that frequency may become large. For this reason, the spread mode is set in situations where the ripple current should be suppressed.

[0035] In spread mode, the carrier frequency (f c1 ,f c2 ), a fundamental frequency F0 (first frequency) and a spreading frequency F1 (second frequency) that is an integer multiple of the fundamental frequency F0 are set alternately.

[0036] Figure 2 shows the carrier frequency (f c1 ,f c2 2 is a diagram illustrating an example of a setting mode of the spread frequency F1. In the example shown in FIG. 2, the spread frequency F1 is set to twice the fundamental frequency F0. In addition, in the spread mode, the time for setting the fundamental frequency F0 (first switching time t 21 ) is set to twice the control period t. Furthermore, the time for setting the spread frequency F1 (the second switching time t 22 ) is also set to twice the control period t.

[0037] Therefore, in the example shown in FIG. 2, in the spread mode, the carrier frequency (f c1 ,f c2 ) alternates between the fundamental frequency F0 and the spread frequency F1 every twice the control period t.

[0038] The spreading frequency F1 is not limited to twice the fundamental frequency F0. In other words, the spreading frequency F1 can be set to any value as long as it is different from the fundamental frequency F0 (especially a value greater than the fundamental frequency F0). However, it is preferable to set the spreading frequency F1 to an integer multiple of the fundamental frequency F0, such as twice, three times, or four times. By setting the carrier wave period (the reciprocals of the fundamental frequency F0 and the spreading frequency F1) to an integer multiple of the control period t in this way, the carrier frequency f c The switching timing and voltage command value (V g * ,V d *) update timing difference (phase difference) is suppressed, and the carrier wave and voltage command value (V g * ,V d * ) can be suitably synchronized. Therefore, in the first switching device 14, it is possible to suppress the deterioration of torque accuracy and the occurrence of torque ripples when the carrier frequency is switched. In particular, the carrier wave and the voltage command value (V g * ,V d * ) is preferably synchronized to make the phase difference between them zero.

[0039] In addition, the first switching time t 21 and the second switching time t 22 can be appropriately set to other than those shown in FIG. 2. In particular, the first switching time t 21 and the second switching time t 22 may be set to different values.

[0040] In addition, the carrier frequency in the spread mode (f c1 ,f c2 The switching can be performed when the instantaneous value of the carrier wave reaches the midpoint (zero point) of the carrier wave amplitude, but it is also possible to switch when the instantaneous value reaches the peak (maximum or minimum) of the carrier wave amplitude.

[0041] By implementing the spreading mode described above, the carrier frequency (f c1 ,f c2 ) at a specific frequency, an increase in ripple voltage caused by the concentration of the current at a specific frequency is suppressed. This makes it possible to suppress noise caused by the operation of the drive motor 12 and the generator 10.

[0042] Next, the execution decision process described above in this embodiment will be described in further detail.

[0043] 3 is a flowchart illustrating the execution decision process in this embodiment. The controller 50 repeatedly executes the routine shown in FIG.

[0044] First, the controller 50 receives the shift position signal S sh and pb status signal S pb Based on vehicle In step S110, the control unit 10 determines whether the selected shift position is either the parking position (the so-called "P" position) or the neutral position (the so-called "N" position), and determines whether the parking brake is operated (step S120).

[0045] Then, when the determination results of both steps S110 and S120 are negative (when it is determined that there is a possibility that the vehicle user O will get off), the controller 50 executes the process of step S130. On the other hand, when the determination results of at least one of steps S110 and S120 are positive (when it is determined that there is no possibility that the vehicle user O will get off), the controller 50 executes the process of step S150.

[0046] The above steps S110 and S120 are performed when the vehicle is stopped. in In this embodiment, the shift position signal S sh and pb status signal S pb is used as the above-mentioned alighting possibility parameter. In particular, this shift position signal S sh and pb status signal S pb In addition to identifying vehicle stopping scenes, functions as a preferable indicator that can eliminate stopping situations in which the vehicle user O is unlikely to disembark (relatively short stops such as waiting at traffic lights) in the identified stopping scenes, and extract stopping situations in which the vehicle user O is likely to disembark (relatively long stops such as when parking).

[0047] 4A is a diagram for explaining the relationship between the likelihood of a vehicle user O getting off when the vehicle is stopped and the level of the vehicle user O's awareness of noise. In FIG. 4A, the electric motor unit MU including the inverter 13 is accommodated together with the engine 20 in the same accommodation space (engine room ER) in the vehicle body, and the engine room ER is separated from the vehicle exterior area C by an engine hood 64. out Assume an example in which the device is configured to be openable and closable with respect to the above.

[0048] In the above-mentioned stopping situation where there is a high possibility of getting off, as shown in the figure, in A vehicle user O in the outside area C out In this case, the physical distance between the vehicle user O and the motor unit MU, which is the noise source, becomes closer, and car The shielding function of both doors 60 and windows 62f is also lost (the only thing blocking the occupant is essentially the engine hood 64). Therefore, the determination as to whether or not the occupant can get out of the vehicle based on the above steps S110 and S120 becomes a logic that can appropriately estimate the level of noise perception.

[0049] Returning to FIG. 3, in step S130, the controller 50 calculates the vehicle speed v as a background noise parameter and a predetermined vehicle speed threshold v th Then, the controller 50 compares the vehicle speed v with the vehicle speed threshold v th If it is determined that the vehicle speed v exceeds the vehicle speed threshold v (if the background noise level is equal to or higher than a certain level), the control mode is set to the basic mode and this routine is terminated (step S160). th If it is determined that it is equal to or lower than the predetermined level (if the background noise level is equal to or lower than a certain level), the process of step S140 is executed.

[0050] In addition, the vehicle speed threshold v th is determined in advance by experiment or simulation, and is stored in an arbitrary storage area accessible by the controller 50.

[0051] Next, in step S140, the controller 50 outputs the open / close state signal S win, and judges whether the vehicle window 62 is open or not. If the controller 50 judges that the window 62 is not open, the controller 50 sets the control mode to the basic mode and ends this routine (step S160). On the other hand, if the controller 50 judges that the window 62 is open, the controller 50 executes the process of step S150.

[0052] Here, the determination in step S140 is made on the premise that the background noise during driving is at a certain level or more, and in In this embodiment, the vehicle user O's awareness of noise is estimated by referring to the shielding effect against noise transmission to the inside of the vehicle. win is used as the first shielding parameter described above. In particular, this open / close state signal S win is inverter 13 to cabin C in It serves as an appropriate indicator for estimating the level of noise insulation against noise transmission inside the building.

[0053] FIG. 4B shows the open and closed states of the vehicle window 62 and the vehicle interior C. in FIG. 13 is a diagram illustrating the relationship between the degree of recognition of noise within a vehicle and the degree of recognition of noise within a vehicle.

[0054] As shown in the figure, when the vehicle window 62 is open while the vehicle is running, the vehicle compartment C in The engine hood 64 is the only shield that blocks noise transmission between the engine hood 64 and the inverter 13. in For vehicle user O inside the vehicle, the state in which the window 62 is open can be said to be a state in which the noise is more noticeable than a state in which the window 62 is closed. In particular, assuming that the background noise is at a certain level or higher, the open / closed state of the window 62 appropriately correlates with the level of noise perception for vehicle user O (whether or not the noise is unpleasant).

[0055] Returning to FIG. 3, in step S150, the controller 50 calculates the generator torque T g and the threshold torque T g_thThen, the controller 50 compares the magnitude of the generator torque T g is a given threshold torque T g_th If the value is equal to or greater than the predetermined value, the diffusion mode is executed and the routine is terminated (step S170). g is the threshold torque T g_th If it is less than this, the control mode is set to the basic mode and this routine is terminated (step S160).

[0056] Here, the generator torque T g Depending on the magnitude of the noise (≈ the current flowing through the generator 10), there may be scenes in which the noise level does not reach a level that would cause discomfort to the vehicle user O. The determination in step S150 is performed with the aim of identifying such scenes. In particular, with the determination logic in step S150, in such scenes where the noise level is small enough to not be a problem, the basic mode can be executed regardless of the determination result of whether the noise is highly perceptible or not.

[0057] In addition, the threshold torque T g_th is the appropriate generator torque T from the viewpoint of identifying the above scene. g is determined in advance by experiment or simulation, and is stored in an arbitrary storage area accessible by the controller 50.

[0058] In addition, the regenerative operation of the generator 10 (T g <0), in the judgment of step S150, the generator torque T g and the threshold torque T g_th A control logic for comparing the above may be adopted.

[0059] According to the switching control method of the present embodiment described above, the following advantageous effects are achieved.

[0060] According to this embodiment, in a vehicle equipped with a generator 10 and a drive motor 12 for running that is operated by the generated power of the generator 10, the carrier frequency f c1A switching control method for regulating

[0061] In this switching control method, the carrier frequency f c1 A fundamental mode that maintains the carrier frequency f at a predetermined fundamental value (fundamental frequency F0) and c1 The control mode of the carrier wave is set to one of the diffusion modes in which the noise generated by the operation of the generator 10 is changed at a predetermined switching period. Then, a noise awareness suggestion amount (S sh ,S pb ,v,S win ) is obtained. If the degree of recognition is estimated to be high based on the noise recognizability suggestion amount (if either step S110 or step S120 is Yes, or if both step S130 and step S140 are Yes), the diffuse mode is executed (step S170). On the other hand, if the degree of recognition is estimated to be low (if both step S110 and step S120 are No, and either step S130 or step S140 is No), the basic mode is executed (step S160).

[0062] As a result, the carrier frequency f of the carrier wave is determined based on the criterion of whether the noise generated by the operation of the generator 10 is easily audible to the vehicle user O. c1 A control mode relating to the above can be determined. More specifically, when it is estimated based on the noise awareness suggestion amount that the current vehicle situation is such that the vehicle user O can easily hear the noise of the generator 10 (is likely to feel discomfort due to the noise), the diffusion mode can be executed to suppress the noise. On the other hand, when it is estimated based on the noise awareness suggestion amount that the current vehicle situation is such that the vehicle user O cannot easily hear the noise (is unlikely to feel discomfort due to the noise), the basic mode can be executed to increase the switching efficiency. In other words, it is possible to suppress a situation in which the diffusion mode is executed (a situation in which losses increase) in a situation in which the noise caused by the operation of the generator 10 is not a problem.

[0063] Therefore, the driving point (Tg ,N g Even in the switching control applied to the generator 10 for which the above-mentioned condition is defined, it is possible to appropriately distinguish between situations in which noise suppression should be prioritized and situations in which efficiency should be prioritized, and it is possible to achieve an appropriate balance between reducing the discomfort caused to the vehicle user O by noise and suppressing the deterioration of fuel efficiency.

[0064] Furthermore, the noise perception suggestion amount is calculated based on a parameter indicating whether the vehicle user O can get off the vehicle when the vehicle is stopped (shift position signal S sh and pb status signal S pb ) Then, when it is determined that there is a possibility of getting off based on the alighting possibility parameter, it is estimated that the noise awareness level is high (Yes in either step S110 or step S120).

[0065] This allows the passenger to refer to the disembarkation possibility parameter and in After identifying a situation in which the vehicle user O who is inside the vehicle gets out of the vehicle and approaches the generator 10, which is a noise source (a situation in which the vehicle user O may feel uncomfortable due to noise), the situation can be estimated as a situation with a high degree of awareness. Therefore, the diffusion mode can be more reliably executed in the situation.

[0066] More specifically, the disembarking possibility parameter includes a shift position selected in the vehicle and / or the on / off state of the parking brake of the vehicle. If the shift position is selected in a transmission cut-off range (P range or N range) that cuts off the transmission of driving force between the vehicle's running drive source (driving motor 12) and the driving wheels and / or if the parking brake is on, it is determined that there is a possibility of disembarking.

[0067] This realizes a more specific aspect of the alighting possibility parameter. In particular, when the shift position is selected in the transmission cut-off range or when the parking brake is on, this is strongly correlated with a situation in which the vehicle is stopped and the vehicle user O is highly likely to alight (a situation in which the vehicle is stopped for a certain period of time or more, such as when parking). Therefore, by estimating such a situation as a situation in which the vehicle user O has a high awareness of noise, the accuracy of determining the control mode can be further improved.

[0068] In addition, the above noise perception suggestion level is based on the noise level in the vehicle cabin C caused by the running of the vehicle. in The background noise parameters that indicate the volume of background noise in the vehicle cabin C in and a first blocking parameter indicating the blocking ability of noise transmission to the inside. If it is determined that there is no possibility of getting off based on the alighting possibility parameter (both steps S110 and S120 are No), the level of awareness of the noise is estimated based on the background noise parameter and the first blocking parameter.

[0069] As a result, assuming that it is determined that there is no possibility of getting off based on the above-mentioned alighting possibility parameter, the vehicle compartment C in In other words, when it is determined that there is no possibility of getting off the vehicle, the background noise caused by the running of the vehicle is estimated through the background noise parameter and the first shielding parameter. noise Sound volume and noise level in cabin C in It is possible to estimate the level of awareness of noise from the perspective of how much of the noise is transmitted inside the vehicle.

[0070] More specifically, the background noise parameter includes the vehicle speed v. The first obscuration parameter is the open / closed state of the vehicle window 62 (open / closed state signal S win ) and the vehicle speed v is a predetermined vehicle speed threshold v thIf it is equal to or less and the window is open, the recognition degree is estimated to be high (Yes in step S130 and Yes in step S140). On the other hand, if it is not (No in step S130 or No in step S140), the recognition degree is estimated to be low.

[0071] This realizes more specific aspects of the background noise parameter and the first shielding parameter. The magnitude of the vehicle speed v correlates with the magnitude of background noise (running noise, wind noise, etc.) caused by traveling. Therefore, by using the vehicle speed v as the background noise parameter, the vehicle interior C in The volume of the background noise inside the vehicle can be appropriately estimated. In addition, the open / close state of the window 62 is a noise source between the generator 10 and the vehicle compartment C. in This correlates with the physical shielding effect of noise transmission between the inside and outside. win By using as the first shielding parameter, the vehicle cabin C in Therefore, the substantial amount of noise transmitted to the inside can be appropriately controlled.

[0072] Therefore, even in a scene where it is assumed that there is no possibility of getting off the vehicle as described above (immediately before the start of travel or during travel), it is possible to appropriately distinguish between a situation where the recognition level is high and a situation where the recognition level is low. As a result, even in such a scene, it is possible to more appropriately distinguish between a situation where the diffusion mode should be executed (a situation where noise caused by the operation of the generator 10 should be suppressed) and a situation where the basic mode should be executed.

[0073] In this embodiment, the output torque of the generator 10 (generator torque T g ) is a given threshold torque T g_th If it is less than this, the basic mode is executed regardless of the estimation result of the level of the recognition degree based on the noise recognition degree suggestion amount (No in step S150 and step S160).

[0074] This makes it possible to suppress the occurrence of a situation in which the diffusion mode is executed in a scene where the noise level generated by the operation of the generator 10 is small enough to not be a problem in the first place. Therefore, it is possible to further limit the scenes in which the diffusion mode should be executed (to increase the opportunities to execute the basic mode), thereby obtaining the effect of further suppressing the deterioration of fuel efficiency.

[0075] In the diffusion mode in this embodiment, the voltage command value V g * A fundamental frequency F0 as a first frequency that is approximately equal to twice the control period t and a spreading frequency F1 as a second frequency that is an integer multiple of the first frequency are alternately set.

[0076] This results in a carrier frequency of f c The switching timing and voltage command value V g * The change in the update timing difference (phase difference) between the carrier wave and the voltage command value V g * Therefore, in the first switching device 14, it is possible to suppress the deterioration of torque accuracy and the occurrence of torque ripples when the carrier frequency is switched.

[0077] Furthermore, in this embodiment, a vehicle is equipped with a generator 10 and a drive motor 12 for running that is operated by the power generated by the generator 10, and a carrier frequency f c1 A controller 50 is provided that functions as a switching control device to regulate

[0078] In particular, the controller 50 controls the carrier frequency f c1 A fundamental mode that maintains the carrier frequency f at a predetermined fundamental value (fundamental frequency F0) and c1 A setting unit sets one of the diffusion modes in which the noise generated by the operation of the generator 10 is changed at a predetermined switching period as a control mode of the carrier wave, and a noise recognition suggestion amount (Ssh ,S pb ,v,S win ) and a control mode determination unit. When the degree of recognition is estimated to be high based on the noise recognizability suggestion amount (when either step S110 or step S120 is Yes, or when both step S130 and step S140 are Yes), the control mode determination unit executes the diffusion mode (step S170). On the other hand, when the degree of recognition is estimated to be low (when both step S110 and step S120 are No, and either step S130 or step S140 is No), the control mode determination unit executes the basic mode (step S160).

[0079] This realizes a control device configuration suitable for executing the switching control method of the present embodiment.

[0080] [Second embodiment] Hereinafter, the second embodiment will be described. The same elements as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. In particular, in this embodiment, the noise recognition degree suggestion amount is calculated by dividing the inverter 13 and the vehicle exterior area C out An example of using a second blocking parameter indicating the degree of blocking of noise transmission between the object and the vehicle will be described.

[0081] FIG. 5 is a flowchart illustrating the execution decision process in this embodiment.

[0082] As shown in the figure, in step S210, it is determined whether or not the engine hood 64 is open by referring to a signal indicating the open / closed state of the engine hood 64. The open / closed state of the engine hood 64 can be detected by known sensors (not shown).

[0083] Here, the determination in step S210 is made assuming that the vehicle is stopped, and the inverter 13 is in the vehicle exterior area C out The noise transmission shielding between the vehicle exterior and the vehicle interior is outThis is executed for the purpose of estimating whether the degree of recognition of the vehicle user O is equal to or higher than a criterion for distinguishing between high and low. That is, in this embodiment, a signal indicating the opening / closing information of the engine hood 64 is used as the above-mentioned second shielding parameter. In particular, the signal indicating the opening / closing information of the engine hood 64 is transmitted from the inverter 13 to the outside area C out It serves as an appropriate index for estimating the level of insulation against noise transmission to a building.

[0084] FIG. 6 shows the engine hood 64 opening / closing information and the vehicle exterior area C out 1 is a diagram illustrating the relationship between the degree of noise recognition in the

[0085] As shown in the figure, when the engine hood 64 is open, the outside area C out 6, the noise generated by the operation of the generator 10 is transmitted directly to the vehicle user O without passing through the engine hood 64. out For the vehicle user O in the vehicle exterior area C, the open state of the engine hood 64 is more noticeable than the closed state of the engine hood 64. out It correlates well with the level of noise perception in the

[0086] In the switching control method of the present embodiment described above, the noise recognition degree suggestion amount is calculated based on the noise recognizability suggestion amount between the motor unit MU (generator 10) and the external area of ​​the vehicle (exterior area C out ) is included. If it is determined that the shielding ability is equal to or less than a certain level based on the second shielding ability parameter, it is estimated that the awareness of the noise is high (Yes in step S210).

[0087] This allows the vehicle exterior area C outIn particular, the second shielding parameter is used to estimate the degree of noise awareness of the vehicle user O in the vehicle exterior area C. out It is possible to estimate the level of noise awareness from the perspective of the actual loudness of the noise heard by vehicle user O in the vehicle.

[0088] More specifically, the second shielding parameter is a value obtained by dividing an accommodation space (engine room ER) inside the vehicle body in which the generator 10 and the first switching device 14 are accommodated into an external area (exterior area C out ) includes the open / closed state of an opening / closing member (engine hood 64) that opens and closes relative to the engine hood 64.

[0089] As a result, the second shielding parameter is calculated by determining whether the vehicle user O is in the vehicle exterior area C out Assuming that the noise source is located in the vehicle exterior area C, out In particular, the engine hood 64 is usually in an open state when the vehicle is stopped and the vehicle user O needs to perform some work or check something by visiting the outside area C. out This is a situation in which there is a probability that the

[0090] Therefore, by referring to the open / closed state of the engine hood 64, it is possible to determine whether the vehicle is stopped and whether the vehicle user O is in the outside area C out and whether the electric motor unit MU is located in the outside area C out It is possible to omit setting an individual parameter for grasping the level of shielding ability against noise transmission of the vehicle occupant O. In other words, by setting the second shielding ability parameter to the open / closed state of the engine hood 64, it is possible to estimate the level of the vehicle occupant O's awareness of noise with a simple control logic.

[0091] Although the embodiments of the present invention have been described above, the above-described embodiments merely illustrate some of the application examples of the present invention, and are not intended to limit the technical scope of the present invention to the specific configurations of the above-described embodiments.

[0092] For example, a configuration may be adopted in which the operating state of the generator 10 is monitored, and when the generator 10 is operating, the execution decision process is executed, and when the generator 10 is not operating, the execution decision process is not executed and the control mode is maintained in the basic mode. Also, a configuration may be adopted in which the operating state of the generator 10 is confirmed and the diffusion mode is executed only when the generator 10 is operating, on the premise that the vehicle user O is estimated to have a high level of awareness of noise (when either step S110 or step S120 is Yes, or when both step S130 and step S140 are Yes). Either control configuration can more reliably suppress an increase in loss (deterioration in fuel efficiency) caused by the execution of the diffusion mode in a scene where the demand for noise suppression is low (a scene where the level of noise caused by the operation of the generator 10 is low).

[0093] Furthermore, in estimating the level of awareness of noise, a plurality of parameters that function as noise awareness suggestive quantities are used, and the generator torque T g To compare with the threshold torque T g_th (Step S150) may be changed.

[0094] More specifically, the scope of disclosure of the specification of this application as originally filed includes: When the noise perception is estimated to be high based on a number of parameters (shift position, on / off of the parking brake, vehicle speed v, opening / closing of windows, and / or opening / closing of the engine hood 64) that function as noise perception indication amounts, the generator torque T g and a given threshold torque T g_th Compare the size of Generator torque T g is the threshold torque T g_th If so, execute the spreading mode; Generator torque Tg is the threshold torque T g_th A switching control method for executing a basic mode even if the recognition degree is estimated to be high when the recognition degree is less than the threshold value, Threshold torque T g_th Also included is a switching control method in which the above-mentioned is changed according to the estimation result of the individual recognition degree based on each parameter or a combination thereof.

[0095] In this way, for example, by referring to the level of individual recognition levels according to each parameter, even in situations where the recognition level is estimated to be high, it is possible to distinguish between situations where the recognition level is relatively high and situations where the recognition level is relatively low, and to set the threshold torque T g_th In particular, in a situation where the degree of awareness is relatively high, the threshold torque T g_th By making the threshold torque T smaller, it becomes difficult to execute the basic mode in the judgment of step S150, and it is possible to prioritize noise suppression. g_th By increasing the value, the basic mode is more likely to be executed, and priority can be given to fuel efficiency.

[0096] For example, a first scene in which the degree of awareness of noise is estimated to be high based on the opening and closing of a window while driving (Yes in step S140) is estimated to be a state in which the degree of awareness of noise is relatively low compared to a second scene in which the vehicle user O opens the engine hood 64 while stopped and approaches the noise source (Yes in step S210). Therefore, the threshold torque T g_th By setting the value of the noise suppression ratio to a relatively small value, a more preferable balance between noise suppression and fuel economy can be achieved.

[0097] Furthermore, the specific form of the noise awareness suggestion amount is not limited to that described in the above embodiment. In other words, any parameter can be adopted as the noise awareness suggestion amount as long as it functions as a vehicle status suggestion amount that can correlate with the level of awareness of the vehicle user O of the noise caused by the operation of the generator 10.

Claims

1. 1. A switching control method for adjusting a carrier frequency of a carrier wave used in PWM control for adjusting power of a generator in a vehicle including a generator and a drive motor for running the vehicle, the method comprising the steps of: setting, as a control mode of the carrier wave, either a basic mode in which the carrier frequency is maintained at a predetermined basic value or a spread mode in which the carrier frequency is changed at a predetermined switching period; a noise awareness suggestion amount that suggests a vehicle condition that correlates with a level of awareness of a vehicle user regarding noise generated by the operation of the generator; When the degree of noise awareness is estimated to be high based on the noise awareness suggestion amount, a diffusion mode is executed in which the carrier frequency is changed at a predetermined switching period. If the degree of recognition is estimated to be low, a basic mode is executed in which the carrier frequency is maintained at a predetermined basic value; the noise perceptibility suggestion amount includes an alighting possibility parameter suggesting a possibility of the vehicle user alighting when the vehicle is stopped, When it is determined that there is a possibility of getting off based on the alighting possibility parameter, the recognition degree is estimated to be high. Switching control method.

2. 2. The switching control method according to claim 1, The exit possibility parameter includes a shift position selected in the vehicle and / or a parking brake on / off of the vehicle, When the shift position is selected in a transmission cut-off range in which the transmission of driving force between a driving source and a driving wheel of the vehicle is cut off, or when the parking brake is on, it is determined that there is a possibility of disembarking. Switching control method.

3. 3. The switching control method according to claim 1, further comprising: the noise recognizability suggestion amount further includes a background noise parameter suggesting a volume of background noise in the vehicle cabin caused by the running of the vehicle, and a first insulativeness parameter suggesting an insulativeness against transmission of the noise into the vehicle cabin; When it is determined that there is no possibility of disembarking based on the disembarking possibility parameter, estimating the level of intelligibility based on the background noise parameter and / or the first masking parameter; Switching control method.

4. 4. The switching control method according to claim 3, The background noise parameters include vehicle speed; the first occlusion parameter includes an open or closed state of a window of the vehicle; When the vehicle speed is equal to or lower than a predetermined vehicle speed threshold and the window is open, the recognition degree is estimated to be high, and when not, the recognition degree is estimated to be low. Switching control method.

5. 1. A switching control method for adjusting a carrier frequency of a carrier wave used in PWM control for adjusting power of a generator in a vehicle including a generator and a drive motor for running the vehicle, the method comprising the steps of: setting, as a control mode of the carrier wave, either a basic mode in which the carrier frequency is maintained at a predetermined basic value or a spread mode in which the carrier frequency is changed at a predetermined switching period; a noise awareness suggestion amount that suggests a vehicle condition that correlates with a level of awareness of a vehicle user regarding noise generated by the operation of the generator; When the degree of noise awareness is estimated to be high based on the noise awareness suggestion amount, a diffusion mode is executed in which the carrier frequency is changed at a predetermined switching period. If the degree of recognition is estimated to be low, a basic mode is executed in which the carrier frequency is maintained at a predetermined basic value; the noise perception suggestion amount includes a second shielding parameter indicating a shielding effect against transmission of the noise between the generator and an external area of ​​the vehicle when the vehicle is stopped; When it is determined that the occlusion degree is equal to or lower than a certain level based on the second occlusion degree parameter, the recognition degree is estimated to be high. Switching control method.

6. 6. A switching control method according to claim 5, the second shielding parameter includes an open / close state of an opening / closing member that opens and closes an accommodation space inside the vehicle body in which the generator is accommodated, to the external area, Switching control method.

7. A switching control method according to any one of claims 1 to 6, When the magnitude of the output torque of the generator is less than a predetermined threshold torque, the basic mode is executed regardless of the estimation result of the level of the noise awareness level based on the noise awareness level suggestion amount. Switching control method.

8. A switching control method according to any one of claims 1 to 7, In the diffusion mode, a first frequency that is approximately twice the control period of a voltage command value calculated as a value of a voltage to be applied to the generator, and a second frequency that is an integer multiple of the first frequency are alternately set; Switching control method.

9. A switching control device that is mounted on a vehicle having a generator and a drive motor for running the vehicle, the switching control device adjusting a carrier frequency of a carrier wave used in PWM control that adjusts the power of the generator, comprising: a setting unit that sets, as a control mode of the carrier wave, one of a basic mode in which the carrier frequency is maintained at a predetermined basic value and a spread mode in which the carrier frequency is changed at a predetermined switching period; an acquisition unit that acquires a noise awareness suggestion amount that suggests a vehicle condition that correlates with a level of awareness of a vehicle user of noise generated by an operation of the generator; a control mode determination unit that executes the diffusion mode when the degree of recognition is estimated to be high based on the noise recognizability suggestion amount, and executes the basic mode when the degree of recognition is estimated to be low, the noise perceptibility suggestion amount includes an alighting possibility parameter suggesting a possibility of the vehicle user alighting when the vehicle is stopped, When the control mode determination unit determines that there is a possibility of disembarking based on the disembarking possibility parameter, the control mode determination unit estimates that the recognition degree is high. Switching control device.

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