JP6299094B2 - Electric vehicle power generation control device - Google Patents

Description

  The present invention relates to a power generation control device for an electric vehicle that can travel by driving a motor that uses electric power from a generator driven by an engine such as an engine as an energy source.

In an electric vehicle such as a series hybrid vehicle that uses a motor driven by receiving power from an engine-driven generator as a power source, it is installed to temporarily charge surplus generated power. When a battery is charged / discharged at a low temperature, deterioration or failure of the battery occurs. Therefore, it is necessary to take a low-temperature protection measure to prevent the battery from being charged / discharged at a low temperature.
Therefore, when the electric vehicle is driven in a low temperature environment where the battery input / output power is limited as described above, it is required to perform direct power distribution control that uses up the electric power generated by the generator without using the electric power generated by the generator. .

  On the other hand, in a vehicle including an electric vehicle, the torque transmission system (wheel drive system) of the wheel has a natural vibration component due to a torsional vibration (crash vibration) of the drive shaft, and the natural vibration component of the wheel drive system is driven by the wheel drive. If the removal or reduction process is not performed during traveling, smooth traveling of the vehicle is impeded.

As a technique for reducing the natural vibration component of the wheel drive system, conventionally, for example, those described in Patent Document 1 and those described in Patent Document 2 have been proposed.
The proposed technique described in Patent Document 1 uses a filter that removes or reduces the natural vibration component of the wheel drive system (hereinafter referred to as a vibration suppression filter), and determines the motor torque command value that contributes to drive control of the drive side motor. After filtering through a vibration filter, it is used for motor drive control.
In addition, the proposed technique described in Patent Document 2 uses a vibration suppression filter to filter a command value for power generation torque (power generation load) that contributes to power generation control of the generator or an engine torque command value that contributes to control of the generator driving engine. It is used for control of a generator or an engine.

JP 2001-045613 A JP 2011-010535 A

However, in the proposed technique of Patent Document 1, the following problems occur during direct distribution control that uses the generated power of the generator by the driving motor for the purpose of protecting the battery in a low temperature environment. .
That is, in the proposed technique of Patent Document 1, the drive torque command value determined to completely consume the generated power is used for the motor drive control after the filtering process by the damping filter even during the direct power distribution control.

For this reason, the power of the frequency component removed by the vibration suppression filter cannot be consumed by the drive side motor, and the amount of power that could not be consumed by the motor is input / output beyond the limit to the battery. End up.
By the way, direct power distribution control is intended to limit the input and output of power to the battery by using up the generated power of the generator with the motor on the drive side for the purpose of protecting the battery in a low temperature environment. However, if the power is input / output to / from the battery exceeding the limit as described above during the direct power distribution control, there is a possibility that the battery will deteriorate or break down.

  In the proposed technology of Patent Document 2, the command value of the power generation torque (power generation load) or the command value of the engine torque for driving the generator is filtered by a damping filter for use in controlling the generator or engine. However, if the natural vibration component of the wheel drive system is removed or reduced and this generated power is completely consumed by the motor on the drive side by direct power distribution control, the input / output power of the battery is limited as required at low temperatures. However, although the natural vibration component of the wheel drive system can be removed or reduced and smooth vehicle travel can be realized, the following problems occur.

  In other words, as in the proposed technology in Patent Document 2, the natural vibration component of the wheel drive system is completely eliminated by simply filtering the power generation torque command value and the generator drive engine torque command value with the damping filter during direct distribution control. There is a problem that it cannot be removed and vibration remains.

  The reason is that the inherent vibration component of the wheel drive system is originally present in the system from the drive torque by the motor to the rotation speed of the drive motor, and this vibration component applies a damping filter to the drive torque command value of the vehicle. This is because it can be removed for the first time.

  On the other hand, when the power generation torque (TG_f) after filtering the power generation torque command value and the generator drive engine torque command value (TG) with the damping filter is used for power generation control, as in the proposed technology of Patent Document 2. The generated power (PG) generated is a value (PG = TG_f × ωG) obtained by multiplying the power generation torque after filtering (TG_f) by the generator rotational speed (ωG).

The drive torque (TM) when this generated power (PG) is completely consumed by the drive motor is the value obtained by dividing the generated power (PG) by the drive motor speed (ωM) (TM = PG ÷ ωM), and the above-described (PG = TG_f × ωG) is substituted into PG in this equation, and the driving torque (TM) is expressed by TM = (TG_f × ωG) / ωM.
That is, the drive torque (TM) is a value obtained by dividing the multiplied power generation torque (TG_f) by the generator rotational speed (ωG) by the motor rotational speed (ωM).

For this reason, the vibration suppression filter is not applied to the value originally desired (power generation torque TG × generator rotation speed ωG ÷ drive motor rotation speed ωM), but only to (power generation torque TG). Therefore, a deviation of (generator rotation speed ωG ÷ drive motor rotation speed ωM) from a desired value will occur.
As a result, there has been a problem that the vibration suppression effect of the natural vibration component of the wheel drive system cannot be exhibited reliably, and vibration remains.

  In the present invention, if the torque value when the engine is operated so as to realize the required driving force of the vehicle is filtered by the vibration damping filter, the torque value is calculated as (the generated torque TG × the number of rotations of the generator). (ωG ÷ drive motor rotation speed ωM), the filter processing of the vibration suppression filter should be applied to the value of the desired value (power generation torque TG × generator rotation speed ωG ÷ drive motor rotation speed ωM). From the viewpoint that the above-mentioned deviation does not occur, a power generation control device for an electric vehicle that embodies this idea and can solve the problem related to the remaining vibration caused by the above-described deviation. The purpose is to provide.

For this purpose, the power generation control device for an electric vehicle according to the present invention is configured as follows.
First, to explain the power generation control device for an electric vehicle as a premise,
This is a power generation control device used for an electric vehicle that can travel by driving a motor that uses electric power from a generator driven by an engine as an energy source.

The power generation control device of the present invention is configured to control based on a drive torque command value of a motor when the engine is operated to generate a required driving force of the vehicle at a predetermined rotational speed and torque ,
Prior to using the drive torque command value of the motor for controlling the power generation device, the motor drive torque command value is filtered by a vibration suppression filter that reduces the natural vibration component of the vehicle, and the motor drive torque command value after the filter process is controlled by the power generation device. It is characterized by being configured to contribute to.

  In the power generation control device for an electric vehicle according to the present invention described above, since the power generation device is controlled (power generation control) based on the torque value after the filter processing, the following effects can be obtained.

  When the torque value after the filter processing is used for motor control (drive control) as in Patent Document 1, it is removed by the vibration suppression filter when direct power distribution control is performed for battery protection at low temperatures. There is a problem that the power of the frequency component cannot be consumed by the motor, and the surplus power is input to and output from the battery, resulting in deterioration and failure of the battery.

Further, as in Patent Document 2, when the power generation torque to the power generation device is processed by the vibration suppression filter, and the power generation device is controlled (power generation control) based on the power generation torque after the filter processing,
Since the damping filter is only applied to the power generation torque, it is not applied to the originally desired vehicle drive torque (power generation torque x generator rotation speed ÷ drive motor rotation speed). There is a problem that a sufficient vibration control effect cannot be expected due to a deviation of (number ÷ drive motor speed).

On the other hand, in the power generation device of the present invention, when controlling the power generation device (power generation control), the torque value in the case where the engine is operated to generate the required driving force of the vehicle with a predetermined operation efficiency is used. In order to use the filtered torque value obtained by filtering the torque value with a vibration suppression filter for control of the power generation device (power generation control),
When direct power distribution control is performed to protect the battery at low temperatures, the power of the frequency component removed by the vibration suppression filter is not input / output to the battery, and the above problems related to the deterioration and failure of the battery are avoided. It can be avoided.

Further, in the power generation device of the present invention, the above torque value is filtered by the vibration suppression filter instead of being used for the power generation device control (power generation control) by processing the power generation torque to the power generation device by the vibration suppression filter. To be used later for power generator control (power generation control)
The vibration suppression filter is applied to the originally desired vehicle drive torque (power generation torque x generator rotation speed ÷ drive motor rotation speed) to achieve a sufficient vibration suppression effect for the natural vibration component of the wheel drive system. Can do.

  That is, according to the power generation device of the present invention, it is possible to reliably remove the natural vibration component of the wheel drive system and to exhibit a sufficient vibration damping effect while guaranteeing the input / output restriction to the battery during direct power distribution control. .

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic system diagram illustrating a drive system of an electric vehicle including a power generation control device according to a first embodiment of the present invention and a control system thereof. It is a flowchart which shows the electric power generation control program which the system controller in FIG. 1 and / or other controllers perform. It is a block diagram according to function which shows the calculation process of the target generated electric power calculation step in FIG. FIG. 3 is a map diagram related to a motor required drive torque map used when obtaining a motor required drive torque in the engine operating point calculation step in FIG. 2. FIG. 3 is a map diagram related to an engine operation characteristic map used when obtaining the best fuel efficiency operation point in the engine operation point calculation step in FIG. 2. It is a block diagram according to the function of the generator control point performed at the generator control step in FIG. It is a block diagram according to function which shows the point of the filter process which the vibration suppression filter process part in FIG. 6 performs. It is the schematic diagram which modeled the torque transmission system of the vehicle in FIG. It is a block diagram according to function of the motor drive control point performed in the motor drive control step in FIG. It is an operation | movement time chart by the conventional electric power generation control apparatus. It is an operation | movement time chart of the electric power generation control by the Example of this invention. It is a block diagram according to the function of the generator control point corresponding to FIG. 6 which shows the power generation control apparatus which becomes 2nd Example of this invention. It is a block diagram according to the function of the generator control point corresponding to FIG. 6 which shows the power generation control apparatus which becomes 3rd Example of this invention.

Hereinafter, embodiments of the present invention will be described in detail based on examples shown in the drawings.
<Configuration of the first embodiment>
1 to 9 are schematic system diagrams showing a drive system of an electric vehicle having a power generation control device according to a first embodiment of the present invention and a control system thereof.

The electric vehicle in the present embodiment is a so-called series hybrid vehicle as shown in FIG. 1, and is equipped with a power generation device 3 including an engine (engine) 1 and a generator 2 directly connected to the engine and driven by the engine. In addition, a drive motor 4 that is driven by using the power generated by the generator 2 as an energy source is mounted.
This vehicle is assumed to be able to travel by driving the driving force of the motor 4 to the left and right driving wheels 6L and 6R by a final reduction gear (including a differential gear device) 5 and driving the left and right driving wheels 6L and 6R.

The control system for the above-described series hybrid vehicle will be briefly described below with reference to FIG.
The generator 2 that constitutes the power generator 3 together with the engine 1 is not only used as an original engine-driven generator, but also by converting the power of the battery 7 from direct current to alternating current by the power generation side inverter 8 and receiving power under control. The engine 1 is also used for cranking when starting, or for assisting the engine 1 with torque by a motor driving force.

Therefore, the power generation-side inverter 8 is interposed between the generator 2 and the battery 7 and functions as follows.
That is, the generator-side inverter 8 converts the generated power of the generator 2 from alternating current to direct current for use in driving the motor 4, and makes it possible to charge the battery 7 with surplus power that cannot be consumed by the motor 4.
The generator-side inverter 8 converts the power of the battery 7 from direct current to alternating current and supplies it to the generator 2 under control when cranking or torque assisting the engine 1 described above, and causes the generator 2 to act as a motor.

A drive-side inverter 9 is interposed between the motor 4 and the battery 7, and the drive-side inverter 9 functions as follows.
In other words, the drive-side inverter 9 converts the DC-converted power by the power-generation-side inverter 8 from direct current to alternating current and supplies it to the motor 4 under control to control the drive of the motor 4, and the motor 4 has wheels 6L and 6R. The electric power generated during the regenerative braking is converted from AC to DC, and the battery 7 can be charged.

In order to realize the engine torque command value commanded from the system controller 10, the engine controller 11 determines the throttle opening, ignition timing, and fuel injection amount of the engine 1 according to signals such as the engine speed and temperature. Adjust.
The generator controller 12 performs switching control of the generator-side inverter 8 according to the state of the generator 2 such as the number of revolutions and voltage in order to realize the power generation torque (power generation load) command value commanded from the system controller 10. .

The battery controller 13 measures a battery charge state SOC (State Of Charge) based on the current and voltage charged / discharged to the battery 7, and outputs the result to the system controller 10.
The battery controller 13 further calculates input power and output power of the battery 7 according to the temperature, internal resistance, and SOC of the battery 7, and outputs these to the system controller 10.
The motor controller 14 performs switching control of the drive-side inverter 9 according to the state of the motor 4 such as the number of rotations and voltage in order to realize the drive torque commanded from the system controller 10.

  The system controller 10 detects the vehicle speed VSP in order to calculate the engine torque command of the engine 1, the generated power command of the generator 2, the drive torque command of the motor 4, and the charge / discharge amount command of the battery 7. In addition to inputting the signal from the sensor 15, the signal from the accelerator opening sensor 16 that detects the accelerator pedal depression amount (accelerator opening APO) by the driver, and the signal from the gradient sensor 17 that detects the road surface gradient θ, The SOC, the input power, the output power, the power generated by the generator 8 and the like from the battery controller 13 are input.

<Power generation control>
Next, the power generation control by the system controller 10 and / or other controllers 11 to 14 is performed when the battery temperature is lowered and charging / discharging to the battery 7 is restricted for the purpose of battery protection, that is, the generator 2 The case where direct power distribution control is performed so that the generated power is consumed for driving the motor 4 and the charge / discharge of the battery 7 is limited or zero is described with reference to the control program of FIG. To do.

In step S21, the target generated power PG * necessary for generating the required driving torque of the vehicle requested by the driver at the current vehicle speed VSP is calculated as follows.
In this calculation, as shown in the block diagram of FIG. 3, first, the motor request drive torque calculation unit 31 searches the motor request drive torque TM * based on the request drive torque map of the motor 4 illustrated in FIG. .

The drive motor torque map of FIG. 4 shows the required drive torque TM * of the motor 4 corresponding to the vehicle drive torque requested by the driver for each combination of the accelerator opening APO and the motor rotation speed ωM (vehicle speed VSP). Obtained in advance by experiments.
When the motor required drive torque TM * shown in FIG. 3 is used to determine the motor required drive torque TM *, the vehicle requested by the driver based on the accelerator opening APO and the motor rotational speed ωM based on the motor required drive torque map shown in FIG. The required drive torque TM * of the motor 4 corresponding to the required drive torque is retrieved.

The motor request output calculation unit 32 in FIG. 3 corresponds to the vehicle request output (power) requested by the driver by multiplying the motor request drive torque TM * obtained by the calculation unit 31 and the motor rotation speed ωM. The required output PM * of the motor 4 is obtained.
In the motor drive loss calculation unit 33, the motor drive of the motor 4 is calculated from the motor request drive torque TM *, the motor rotation speed ωM, and the input voltage (or battery voltage) to the drive side inverter 9 based on the drive loss map of the motor 4. Find the loss.

The adder 34 obtains the target generated power PG * by adding this motor drive loss to the motor required output PM *.
This target generated power PG * is the generated power PG required to generate the required drive torque of the vehicle (motor required drive torque TM *) requested by the driver based on the current vehicle speed VSP (motor rotational speed ωM). *

  In step S22 of FIG. 2, the operating point of the engine 1 (engine speed and engine torque at which the engine output corresponding to the target generated power PG * is obtained while considering the fuel efficiency and response of the engine 1 is taken into consideration. ).

  Specifically, the operation characteristic map of the engine 1 illustrated in FIG. 5, that is, the two-dimensional coordinates of the engine speed (generator rotational speed target value ωG *) and the engine torque (engine torque target value TE0 *) are previously stored. Engine output (target) based on the engine 1 iso-output line (combination of rotation speed and torque that generates the corresponding output) and the best fuel consumption line (combination of rotation speed and torque that generates each output at the best fuel consumption) From the generated power PG *), the engine speed (generator rotational speed target value ωG *) required for the engine 1 to be operated in a manner capable of realizing the target generated power PG * with the best fuel efficiency, and the engine torque (engine Torque target value TE0 *) is obtained.

In step S23 of FIG. 2, the generator 2 (the power generation device 3 including the engine 1) is controlled by the processing shown in the block diagram of FIG.
In block 41 of FIG. 6, the target generated power PG * is obtained by the above-described calculation in steps S21 and S22 of FIG. 2, and this target generated power PG * can be achieved with the best fuel efficiency. And a combination of the engine torque target value TE0 *.

Of the generator rotational speed target value ωG * and engine torque target value TE0 * obtained in block 41, the engine torque target value TE0 * is supplied as it is to the engine controller 11 as the engine torque command value TE * for controlling the engine 1. To contribute.
However, the generator rotational speed target value ωG * is not used as it is for the rotational speed control of the generator 2, but is used to estimate the motor torque value obtained when the generator rotational speed target value ωG * is achieved. The estimated torque value is filtered by a vibration suppression filter that reduces the natural vibration component of), and then this torque value is converted into a power generation torque command value TG *. This power generation torque command value TG * is used to control the generator 2. The generator rotational speed target value ωG * is realized by power generation torque control incorporating a vibration damping filter process.

As will be described in detail below, the subtractor 42 calculates the difference ΔωG from the target value of the generator rotation speed by taking the difference between the generator rotation speed target value ωG * and the generator rotation speed measurement value ωG.
The first power generation torque command value calculation unit 43 applies a proportional control gain P to the generator rotational speed deviation ΔωG, and eliminates the deviation ΔωG to make the generator rotational speed measurement value ωG coincide with the target value ωG *. The power generation torque command value TG1 * is calculated.

The subtractor 44 subtracts the generator disturbance torque estimated value ΔTG_est estimated as described later in blocks 45 to 47 from the above-mentioned first generated torque command value TG1 * to obtain a second difference that is the difference between the two. Obtain the power generation torque command value TG2 *.
This subtraction process is for removing disturbances when disturbances such as engine torque are applied to the generator 4.

An estimation procedure of the generator disturbance torque estimated value ΔTG_est performed in the blocks 45 to 47 will be described below.
The block 45 includes a transfer function Gg ′ (s) that models the transfer characteristic Gg (s) of the rotational speed with respect to the torque input of the generator 4, and is finally determined by the vibration suppression filter processing unit 48 as described later. The generator torque command value TG * is passed through this transfer function Gg ′ (s) to calculate the generator rotational speed ideal value ωG_ref.
The transfer function Gg ′ (s) is approximated by the following equation where Jg is the total moment of inertia of the generator 4.
Gg '(s) = 1 / (Jg ・ s) (1)

In block 46, the generator rotation speed ideal value ωG_ref is subtracted from the generator rotation speed measurement value ωG to calculate the generator rotation speed disturbance deviation ΔωGd.
The block 47 includes a transfer function represented by an expression of H (s) / Gg ′ (s) using a low-pass filter H (s) of the same order (primary) as the transfer function Gg ′ (s), and The generator torque disturbance estimated value ΔTG_est is passed through this transfer function H (s) / Gg ′ (s) to obtain the generator disturbance torque estimated value ΔTG_est.
Note that the time constant of the low-pass filter can be arbitrarily set by calculation or experiment in consideration of disturbance response and stability.

The generator disturbance torque estimated value ΔTG_est obtained in block 47 is input to the subtractor 44 and contributes to the calculation of the second power generation torque command value TG2 * as described above.
The vibration suppression filter processing unit 48 is a filter for reducing the natural vibration component of the vehicle (wheel drive system). The second power generation torque command value TG2 * is passed through the filter, and the vehicle (wheel drive system) The final power generation torque command value TG * after the filter processing from which the natural vibration component has been removed is obtained.

Hereinafter, the filter processing of the second power generation torque command value TG2 * executed by the vibration suppression filter processing unit 48 will be described with reference to FIG.
Note that the filtering process is not limited to the second power generation torque command value TG2 *, and if it is not necessary to consider the generator disturbance torque estimated value ΔTG_est, the first power generation torque command value TG1 * may be filtered. In FIG. 7, the target of the filtering process is described as a pre-filtering power generation torque command value TG0 * (TG2 * or TG1 *).

7 divides the generator rotational speed measurement value ωG by the motor rotational speed ωM to calculate a power generation drive speed ratio γ that is a total speed ratio of the generator 2 and the motor 4.
At this time, if the motor rotation speed ωM is smaller than a predetermined minute rotation speed, the zero rotation is prevented by limiting to the minute rotation speed.
The predetermined minute rotation speed is set by calculation or experimental value.

The multiplier 52 multiplies the generator efficiency ηG and the motor efficiency ηM to calculate the power generation drive efficiency η that is the total efficiency of the generator 2 and the motor 4.
The generator efficiency ηG uses a generator efficiency table prepared in advance by experiments, calculations, etc. based on the power generation torque command value TG *, the power generator rotation speed measurement value ωG, and the power generation side inverter input voltage (or battery voltage). To calculate.
The motor efficiency ηM is a driving machine prepared in advance by experiments and calculations based on the driving motor torque command value TM * (or required driving torque), the driving motor speed ωM, and the driving side inverter input voltage (or battery voltage). Calculate using the efficiency table.

In the multiplier 53, the power generation drive conversion coefficient ν between the generator 2 and the motor 4 is obtained by multiplying the power generation drive speed ratio γ determined by the divider 51 and the power generation drive efficiency η determined by the multiplier 52. Ask.
The multiplier 54 obtains a motor drive torque estimated value TM_est corresponding to the power generation torque command value TG0 * by multiplying the power generation torque command value TG0 * before filtering by the power generation drive conversion coefficient ν.

  The vibration suppression filter 55 applies a vibration suppression filter characteristic Gv (s) to the motor drive torque estimated value TM_est to remove a natural vibration component of the vehicle (wheel drive system), and a filtered motor drive torque estimated value TM_est * Is calculated.

The damping filter characteristic Gv (s) is set as follows.
FIG. 8 is a diagram in which a torque transmission system of a vehicle is modeled, and the equation of motion can be expressed by the following equations (2) to (6).

The Laplace transform types of the expressions (2) to (6) are represented by the following expressions (7) to (11).

From these equations (7) to (11), the transfer characteristic from the motor torque to the drive motor rotation speed is expressed by the following equation.

Further, rearranging equation (14), the following equation is obtained.

In this equation, ζ _P and ω _P are the damping coefficient and natural vibration frequency of the torque transmission system of the vehicle.
In general electric vehicles and hybrid vehicles, the value of the damping coefficient ζ _P of the torque transmission system is less than 1. For this reason, Gp (s) is a vibration system.

Here, the ideal characteristic from the drive motor torque to the drive motor rotation speed is expressed by the following equation, with ζ _P in Equation (15) set to 1. By setting ζ _P to 1, Gm (s) becomes a non-vibrating system.

The damping filter Gv (s) is composed of the inverse of the ideal characteristic Gm (s) and the transfer function Gp (s) of the torque transmission system, and is expressed as follows using equations (15) and (16): Can do.

  As described above, when the vehicle is driven using the torque command value subjected to the damping filter Gv (s), the vibration characteristic Gp (s) can be converted to the non-vibration characteristic Gm (s).

In the divider 53 of FIG. 7, the final power generation torque command value TG * is calculated by dividing the motor drive torque estimated value TM_est * after filtering by the vibration suppression filter 55 by the power generation drive conversion coefficient ν.
In addition, when the power generation drive conversion coefficient ν is smaller than a minute predetermined value, the division by zero is prevented by limiting to the minute predetermined value.
The minute predetermined value can be arbitrarily set by calculation or experiment.

  In step S24 of FIG. 2, the motor torque command value TM for using the generated power generated by the power generator 3 including the engine 1 and the generator 2 without excess or deficiency in the motor 4 by the process shown in the block diagram of FIG. * Is calculated, and the drive of the motor 4 is controlled based on this.

In the motor drive loss calculation unit 61, based on the drive loss map of the motor 4 according to the motor drive power, the motor rotation speed, and the drive side inverter input voltage, from the generated power, the motor rotation speed, and the drive side inverter input voltage, The motor drive loss of the motor 4 is obtained.
Here, the generated power is calculated from the product of the DC current of the generator 2 and the generator-side inverter input voltage. The generator loss is added to the product value of the generator torque command value TG * and the generator rotational speed ωG. The value may be generated power.

In the subtractor 62, the motor drive power command value PM * is obtained by subtracting the motor drive loss from the generated power.
The divider 63 obtains the final motor drive torque command value TM * by dividing the motor drive power command value PM * by the motor rotation speed ωM, and contributes to the drive control of the motor 4.
At this time, if the motor rotation speed ωM is lower than a minute set value, the motor rotation speed ωM is limited to this minute set value, thereby avoiding the division by zero.
Further, the final motor drive torque command value TM * is limited so as not to increase or decrease beyond a predetermined upper and lower limit value, thereby protecting the motor 4.

  According to the power generation control device of the present embodiment configured as described above, in the direct power distribution control, the power generated by the generator 2 can be consumed for driving the motor 2 without leaving the power, and the power input to the battery 7 can be performed. The natural vibration of the vehicle (wheel drive system) can be surely removed while limiting the output and protecting it.

<Effect of the first embodiment>
The effects of the power generation control device of the present embodiment described above will be described below based on the operation time chart of this embodiment of FIG. 11 while comparing with the operation time chart of the conventional device of FIG.
FIGS. 10 and 11 show that during direct power distribution control for limiting battery input / output power to a minute predetermined value or less for battery protection at a low temperature, when the accelerator pedal is depressed from a constant vehicle speed traveling state at instant t1. FIG. 6 is an operation time chart showing operations in the case of shifting to accelerated traveling as time-series changes in motor rotation speed ωM, drive shaft torque TM, and power (motor drive power and battery input / output power).

  First, conventional power generation control will be described with reference to FIG. 10. Conventionally, since the vibration damping filter processing is performed on the power generation torque set to achieve the target power generation, the generated power is used up by driving the motor 4 without surplus. Therefore, although the battery input / output power is kept at 0 kW as indicated by the broken line, the battery protection function can be performed as desired, but the vibration control filter process is not performed on the motor control system on the drive side, causing the following problems. .

As described above, the value to be filtered for vibration suppression is the value of (power generation torque TG × generator rotation speed ωG ÷ motor rotation speed ωM). Therefore, the vibration suppression filter processing is not applied to (generator rotation speed ωG ÷ motor rotation speed ωM), and the wheel drive system has a unique amount corresponding to the deviation (generator rotation speed ωG ÷ motor rotation speed ωM). The vibration component cannot be removed.
For this reason, there is a problem that the vibration damping effect cannot be surely exerted, and vibrations as shown in the drawing remain in the drive shaft torque TM and the motor rotational speed ωM at the instants t1 to t2 in FIG.

On the other hand, in the power generation control device of this embodiment, the vibration generation filter is not directly applied to the power generation torque, but the power generation torque (estimated value) TG0 * is temporarily set as the drive torque (estimated value) as described above with reference to FIG. ) Converted to TM_est, this drive torque (estimated value) TM_est is processed by the damping filter 55 to obtain a filtered drive torque (estimated value) TM_est *, and this filtered torque (estimated value) TM_est * is calculated In order to determine the final power generation torque command value TG * by dividing by the power generation drive conversion coefficient ν, and to contribute to the control (power generation control) of the generator 4,
The vibration suppression filter 55 is applied to the drive torque (estimated value) TM_est and used for power generation control.

For this reason, according to the present embodiment, it is no longer possible to remove the natural vibration component of the wheel drive system by the amount of deviation described above, and the drive shaft torque TM and the motor rotation speed ωM over time at the instants t1 to t2 in FIG. As is apparent from the change, smooth acceleration is possible without inducing any natural vibration of the wheel drive system.
In addition, the function of using the generated power in the driving of the motor 4 without leaving all of the power required for direct power distribution control is obtained in the same way as in the prior art, and the battery input / output power is kept at 0 kW as shown by the broken line. Thus, the battery protection function can be obtained as desired.

  In this embodiment, as described above with reference to FIG. 7, the motor drive torque estimated value TM_est corresponding to the power generation torque command value TG0 * is obtained by multiplying the power generation torque command value TG0 * before filtering by the power generation drive conversion coefficient ν. In addition, in order to obtain the final generated torque command value TG * by dividing the filtered drive torque (estimated value) TM_est * by the generated drive conversion coefficient ν, not only the generated drive speed ratio γ but also the generated drive efficiency η Therefore, the following effects can be obtained.

Considering the power generation drive efficiency η that is the total efficiency of the generator 2 and the motor 4 during the direct power distribution control, the drive torque command value TM * can be considered as follows.
First, the generator machine output TG × ωG is obtained from the generator torque TG and the generator rotation speed ωG, and the generator efficiency ηG is applied when converted into electric power by an inverter or the like. Therefore, the generated power PG is PG = TG × ωG × ηG.

Next, since this generated power PG is consumed by the motor 4 without being left behind, the motor power PM becomes PM = PG.
The motor efficiency PM is multiplied from the motor power PM to obtain the motor machine output PM ′, and the drive torque command value TM * is obtained by dividing the motor machine output PM ′ by the motor rotation speed ωM.
That is, TM * = PG × ηM / ωM = TG × ωG × ηG × ηM / ωM = TG × (ωG / ωM) × (ηG × ηM).

Here, if η = ηG × ηM, it can be expressed as TM * = TG × γ × η.
Therefore, by using the total efficiency η (ηG × ηM) of the generator 2 and the motor 4 in addition to the power generation drive speed ratio γ (ωG / ωM), the motor drive torque estimated value TM_est can be estimated more accurately. The power generation torque command value TG * that can reliably remove the natural vibration of the wheel drive system can be calculated.

  However, in this embodiment, as shown in FIG. 7, when the motor drive torque estimated value TM_est corresponding to the power generation torque command value TG0 * is obtained from the power generation torque command value TG0 * before filtering, the driving torque after filtering ( (Estimated value) When determining the final power generation torque command value TG * from TM_est *, the power generation drive conversion coefficient ν is used, but the power generation drive speed ratio γ may be used instead of the power generation drive conversion coefficient ν. .

In this case, the power generation drive efficiency η is not reflected in the control, and although the reduction in control accuracy cannot be denied by that amount, substantially the same effect as the case where the power generation drive conversion coefficient ν is used is obtained as follows. Can do.
During direct power distribution control, the generated power is consumed by the motor 4 without excess, so the drive torque command value TM * is calculated as TM * = PG / ωM from the generated power PG and the motor rotation speed ωM.

Here, since the generated power PG can be expressed as PG = TG × ωG from the generated torque TG and the generator rotational speed ωG, the final drive torque command value TM * is TM * = TG × ωG / ωM. Can be represented.
Therefore, by using the power generation drive speed ratio γ (ωG / ωM), it is possible to accurately estimate the drive torque estimated value from the power generation torque command value, and after applying a damping filter to the drive torque estimated value By converting again into the power generation torque command value, it is possible to calculate a power generation torque command value that can reliably remove the natural vibration of the wheel drive system.

<Power generation control of the second embodiment>
FIG. 12 is a functional block diagram similar to FIG. 6 showing the power generation control apparatus according to the second embodiment of the present invention.
Also in this embodiment, the basic configuration is the same as described above with reference to FIGS. 1 to 9, and the generator control performed in step S23 of FIG. 2 is as shown in the block diagram of FIG. 12 instead of FIG. The only difference is that
Accordingly, in FIG. 12, blocks that function in the same way as in FIG. 6 are given the same reference numerals.

In the present embodiment, the blocks 43 to 47 between the subtractor 42 and the damping filter processing unit 48 in FIG. 6 are replaced with a first power generation torque command value calculation block 70.
In block 70, based on the generator rotational speed deviation ΔωG between the generator rotational speed target value ωG * and the generator rotational speed measured value ωG obtained by the subtractor 42, this is multiplied by the proportional control gain Kp. The proportional control amount (torque value) for setting ΔωG = 0 is calculated, and the integral value (ΔωG / s) of the generator rotational speed deviation deviation ΔωG is multiplied by the integral control gain Ki to integrate ΔωG = 0. A control amount (torque value) is calculated, and these proportional control amount (torque value) and integral control amount (torque value) are added together to obtain the first power generation torque command value TG1 *.

  The vibration suppression filter processing unit 48 is a filter for reducing the natural vibration component of the vehicle (wheel drive system), and passes the first power generation torque command value TG1 * through the filter, so that the vehicle (wheel drive system) The final power generation torque command value TG * after the filter processing from which the natural vibration component has been removed is obtained.

  The vibration suppression filter processing unit 48 has the same configuration as described above with reference to the block diagram of FIG. 7, but in the present embodiment, as clearly shown in FIG. 7, the first power generation torque command value TG1 * is pre-filtered. The generated torque command value TG0 * is input to the multiplier 54, where the pre-filtered generated torque command value TG0 * (TG1 *) and the generated drive conversion coefficient ν (generated drive speed ratio γ × generated drive efficiency η) A motor drive torque estimated value TM_est corresponding to the power generation torque command value TG0 * (TG1 *) is obtained by multiplication.

Next, the motor drive torque estimated value TM_est * is obtained by applying the vibration suppression filter 55 of FIG. 7 to the motor drive torque estimated value TM_est to calculate the filtered motor drive torque estimated value TM_est * from which the natural vibration component of the vehicle (wheel drive system) has been removed.
Further, the divider 53 divides the filtered motor drive torque estimated value TM_est * by the power generation drive conversion coefficient ν, thereby calculating the final power generation torque command value TG * and contributing to the control of the generator 2.

<Effect of the second embodiment>
Even in the power generation control device of the second embodiment described above, instead of directly applying a vibration suppression filter to the power generation torque, the power generation torque (estimated value) TG0 * is temporarily converted into a drive torque (estimated value) TM_est, The drive torque (estimated value) TM_est * after processing this drive torque (estimated value) TM_est by the vibration suppression filter 55 is obtained, and this filtered drive torque (estimated value) TM_est * is divided by the power generation drive conversion coefficient ν. In order to find the final power generation torque command value TG * and contribute to the control of generator 4 (power generation control),
The vibration damping filter 55 is applied to the drive torque (estimated value) TM_est and is used for power generation control. The same effect as that of the first invention described above with reference to FIG. 11, that is, the drive shaft torque at the instants t1 to t2 in FIG. As shown by the change with time of TM and motor rotation speed ωM, the natural vibration of the wheel drive system can be removed from the drive shaft torque TM and motor rotation speed ωM, and smooth acceleration is possible.

<Power generation control of the third embodiment>
FIG. 13 is a functional block diagram similar to FIG. 6 showing the power generation control apparatus according to the third embodiment of the present invention.
Also in this embodiment, the basic configuration is the same as described above with reference to FIGS. 1 to 9, and the generator control performed in step S23 of FIG. 2 is as shown in the block diagram of FIG. 13 instead of FIG. The only difference is that
Therefore, in FIG. 13, blocks having the same functions as those in FIG.

  In the first and second embodiments (FIGS. 6 and 12) described above, the processing by the damping filter processing unit 48 is performed on the power generation torque command value TG0 * (TG1 * or TG2 *) obtained from the generator rotational speed deviation ΔωG. However, in this embodiment, the processing by the damping filter processing unit 48 is performed on the engine torque target value TE0 *.

  This filter processing can be performed in the same manner as in the first and second embodiments by replacing the power generation torque command value TG0 * (TG1 * or TG2 *) in FIG. 7 with the engine torque target value TE0 *. TE0 * is filtered by the vibration suppression filter processing unit 48 to obtain the engine torque command value TE *, which contributes to engine control by the engine controller 11.

Then, the generator rotational speed target value ωG * that no longer requires processing by the vibration suppression filter processing unit 48 is input to the generator rotational speed control unit 80.
The generator rotation speed control unit 90 obtains the second power generation torque command value TG2 * in the same manner as in blocks 42 to 47 in FIG. 6, and uses this as the final power generation torque command value TG * as it is. To help control
Alternatively, the first power generation torque command value TG1 * is obtained in the same manner as in blocks 42 and 70 in FIG. 12, and this is used as the final power generation torque command value TG * as it is for the control of the generator 2.

<Effect of the third embodiment>
Even in the power generation control device of the third embodiment described above, the vibration suppression filter process is not performed directly on the generated torque but on the torque target value TE0 * of the engine 1 that drives the generator 2. In order to contribute to the operation control of the engine 1, that is, the control of the generator 4 (power generation control)
As shown by the effect similar to that of the first invention described above with reference to FIG. 11, that is, the change over time of the drive shaft torque TM and the motor rotational speed ωM at the instants t1 to t2 in FIG. The natural vibration of the drive system can be removed, and smooth acceleration is possible.

1 Engine (Engine)
2 Generator
3 Power generator
4 Drive motor (motor)
5 Final reduction gear
6L, 6R left and right drive wheels
7 Battery
8 Power generation side inverter
9 Drive side inverter
10 System controller
11 Engine controller
12 Generator controller
13 Battery controller
14 Motor controller
15 Vehicle speed sensor
16 Accelerator position sensor
17 Gradient sensor
31 Motor required drive torque calculator
32 Motor request output calculation section
33 Motor drive loss calculator
34 Adder
41 Engine operating point calculation block
42 Subtractor
43 First power generation torque command value calculation section
44 Subtractor
45-47 computation block
48 Vibration suppression filter processor
51,56 Divider
52-54 multiplier
55 Damping filter
61 Motor drive loss calculator
62 Subtractor
63 Divider
70 First power generation torque command value calculation block
80 Generator rotation speed controller

Claims (4)

In a power generation control device for an electric vehicle capable of traveling by driving a motor using an electric power from a generator driven by an engine as an energy source,
The power generation device including the engine and the generator has a power generation torque command value TGO ^* before filtering or a value before filtering when the engine is operated to generate a required driving force of the vehicle at a predetermined rotational speed and torque . It is configured to control based on the motor drive torque estimated value TM est corresponding to the engine torque target value TEO ^* ,
Prior to using the estimated motor driving torque value TM est for control of the power generation device, the motor driving torque command value TM est obtained by the filtering process is filtered by a damping filter that reduces the natural vibration component of the vehicle. ^* Is configured to contribute to the control of the power generator,
An electric power generation control device for an electric vehicle. The power generation control device for an electric vehicle according to claim 1,
Motor drive corresponding to the pre-filtering power generation torque command value TGO ^* obtained by the rotational speed of the generator when the engine is operated to generate the required driving force of the vehicle at the predetermined rotational speed and torque and configured to contribute to the torque estimated value TM est the filtering process above motor drive torque command value after the filtering process obtained by TM est ^* to control of the power generation device,
An electric power generation control device for an electric vehicle. In the power generation control device for an electric vehicle according to claim 2,
In estimating the motor drive torque estimated value TM est , a power generation drive speed ratio γ that is a speed ratio between the rotational speed ωG of the generator and the rotational speed ωM of the motor, and the engine has the predetermined rotational speed and From the power generation torque command value TGO ^* before filter processing for realizing the generator rotational speed target value corresponding to the engine rotational speed necessary for generating the required driving force of the vehicle by torque, these power generation driving speed ratios The motor drive torque estimated value TM_est is obtained by multiplying γ and the power generation torque command value TGO ^* before filtering ,
The motor drive torque estimated value TM_est * after the filter processing obtained by the filter processing of the motor drive torque estimated value TM_est is divided by the power generation drive speed ratio γ to control the power generation device.
An electric power generation control device for an electric vehicle. In the power generation control device for an electric vehicle according to claim 3,
Instead of the power generation drive speed ratio γ, the power generation drive speed ratio γ is configured to use a power generation drive conversion coefficient ν obtained by multiplying the generator and motor efficiency ηG, ηM,
An electric power generation control device for an electric vehicle.

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