JP2017073934A - Power supply control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power supply control device which can appropriately control a charge amount of a high voltage power supply 20 as a first power supply and a charge amount of an intermediate voltage power supply 30 as a second power supply in order to prepare for changes in a gradient state of a road surface on which a vehicle travels.SOLUTION: When a power supply control device determines that a road surface on which a vehicle is traveling has an upward gradient, it operates a power converter in such a manner that power is supplied from an intermediate voltage power supply 30 to the high voltage power supply 20 until a charge amount ELr of the intermediate voltage power supply 30 drops down to an intermediate voltage lower limit value ELmin. When a power supply control device determines that a road surface on which the vehicle is traveling has a downward gradient, it operates the power converter in such a manner that power is supplied from the high voltage power supply 20 to the intermediate voltage power supply 30 until the charge amount ELr of the intermediate voltage power supply 30 rises up to an intermediate voltage upper limit value ELmax.SELECTED DRAWING: Figure 6

Description

  The present invention provides a first power source that transmits and receives power to and from a rotating electrical machine that is an in-vehicle main machine, a second power source that transfers power to and from a load other than the rotating electrical machine, and the first power source and the second power source. The present invention relates to a power supply control device applied to a vehicle comprising:

  As this type of power supply control device, as can be seen in Patent Document 1 below, a first power supply, a second power supply having a smaller capacity and a larger output than the first power supply, and a first power supply and a second power supply What is applied to a vehicle provided with the power converter which enables electric power transmission between is known. In the following Patent Document 1, a battery is used as the first power source, and a capacitor is used as the second power source.

  The power supply control device sets the first power transfer rate from the first power supply to the second power supply via the power converter to be smaller as the vehicle speed is higher, and from the second power supply to the first power supply as the vehicle speed is higher. The second power transfer rate through the power converter is set large. As a result, loss due to power transfer between the first power source and the second power source is reduced.

Japanese Patent No. 5580914

  By the way, in order to make effective use of the first power source and the second power source, such as not transferring useless power between the first power source and the second power source, the potential energy larger than the kinetic energy of the vehicle is optimized. There is a need to. For this optimization, it is necessary to grasp the gradient information of the road surface on which the vehicle travels. That is, it is required that the respective charge amounts of the first power source and the second power source be appropriate values in preparation for a change in the gradient state of the road surface on which the vehicle travels.

  The main object of the present invention is to provide a power supply control device capable of appropriately adjusting the charge amounts of the first power supply and the second power supply in preparation for a change in the gradient state of the road surface on which the vehicle travels.

  Hereinafter, means for solving the above-described problems and the operation and effects thereof will be described.

  The present invention includes a first power source (20; 21) that exchanges power with a rotating electrical machine (71) that is a vehicle-mounted main machine, and a second power source (30; that transmits and receives power to and from a load (50) other than the rotating electrical machine). 31) and a power converter (40) that connects the first power source and the second power source so as to be able to transmit power bidirectionally, the first power source and the second power source. One of them is a capacitive power source, the other is an output power source, the capacitive power source has a larger amount of power that can be stored than the output power source, and the output power source is the capacitive power source. Based on the determination result by the gradient determination unit (80) that determines whether the gradient of the road surface on which the vehicle travels is an ascending gradient or a descending gradient, and the output is larger than the power source , One of the first power source and the second power source A selection unit (80) that selects one of the power sources as a power source and the other as a power source, and operates the power converter so that power is supplied from the power source to the power source And an operation unit (80).

  A vehicle to which the above invention is applied includes a first power source that exchanges power with a rotating electrical machine, a second power source that exchanges power with a load other than the rotating electrical machine, and a bidirectional connection between the first power source and the second power source. Is provided with a power converter connected to be capable of transmitting power. Thereby, electric power can mutually be complemented between the 1st power supply and the 2nd power supply. However, since the change in the amount of charge per hour for this complementation, that is, the magnitude of the power, is limited by the maximum power of the power converter, the amount of charge must be kept so that each power supply does not enter an overcharge / overdischarge state. It is necessary to appropriately control the power of the power converter according to the state.

  On the premise of this configuration, in the above invention, the gradient determination unit determines whether the gradient of the road surface on which the vehicle travels is an ascending gradient or a descending gradient. Then, based on the determination result, either one of the first power supply and the second power supply is selected as the supply source power supply, and the other is selected as the supply destination power supply. Then, the power converter is operated so that power is supplied from the supply source power source to the supply destination power source. As described above, in the above invention, by using the determination result by the gradient determination unit, it is possible to appropriately adjust the charge amounts of the first power source and the second power source in preparation for the change in the gradient state of the road surface on which the vehicle travels. Thereby, the frequency with which the charge amounts of the first power source and the second power source become excessive and insufficient can be reduced, and the first power source and the second power source can be effectively utilized. Accordingly, loss due to power transfer can be reduced.

  Here, as the selection unit, for example, when the gradient determination unit determines that the gradient is an upward gradient, the second power source is selected as the source power source, and the first power source is selected as the source power source. You can adopt what you want. In this case, as the operation unit, when it is determined by the gradient determination unit that it is an upward gradient, the first power supply from the second power supply until the charge amount of the second power supply reaches the lower limit value of the control range. What operates the said power converter so that electric power is supplied to a power supply is employable.

  In a situation where the vehicle travels on an uphill road, it is desirable to reduce the amount of charge of the second power supply in advance in preparation for regenerative power generation of the rotating electrical machine on the subsequent downhill road. According to the above invention, the first power source is charged by the discharged power of the second power source while the vehicle is traveling on the uphill road. For this reason, the charge amount of the 2nd power supply can be reduced in preparation for the regenerative power generation at the time of subsequent descent.

  Further, as the selection unit, for example, when the gradient determination unit determines that the gradient is a downward gradient, the first power source is selected as the source power source, and the second power source is selected as the destination power source. Things can be adopted. In this case, as the operation unit, when it is determined by the gradient determination unit that the gradient is a downward gradient, the second power supply from the first power supply reaches the second value until the charge amount of the second power supply reaches the upper limit value of the control range. What operates the said power converter so that electric power is supplied to a power supply is employable.

  In a situation where the vehicle travels on a downhill road, it is desirable to increase the charge amount of the second power source in advance in preparation for powering operation of the rotating electric machine on the subsequent uphill road. According to the above invention, the second power source is charged by the discharged power of the first power source while the vehicle is traveling on the downhill road. For this reason, the charge amount of the second power source can be increased in preparation for powering operation of the rotating electrical machine during the subsequent climbing.

The figure which shows the whole structure of the vehicle-mounted system which concerns on one Embodiment. The flowchart which shows the procedure of the charging / discharging process of a power supply. The figure which shows the relationship between the input / output limit value of medium voltage power supply which is a capacity type power supply, and medium voltage charge. The figure which shows the relationship between the input / output limit value of the high voltage power supply which is an output type power supply, and a high voltage charge amount. The figure which shows the relationship between medium voltage | pressure side request | requirement electric power and medium voltage | pressure charge amount. The flowchart which shows the procedure of the calculation process of transformation required power. The figure which shows the calculation method of the power conversion request | requirement power in case a driving | running | working road surface is an uphill grade and a downhill grade. The figure which shows the calculation method of the power conversion request | requirement power in case a driving | running | working road surface is other than an uphill grade and a downhill grade. A time chart for explaining prediction electric power. The figure which shows the whole structure of the vehicle-mounted system which concerns on other embodiment.

  Hereinafter, an embodiment in which a power supply control device according to the present invention is applied to a vehicle will be described with reference to the drawings. The vehicle according to the present embodiment is a hybrid vehicle in which a rotating electric machine and an internal combustion engine are mounted as a driving power source.

  As shown in FIG. 1, the vehicle includes a power supply system 10. The power supply system 10 includes a high voltage power supply 20 as a first power supply and a medium voltage power supply 30 as a second power supply. In the present embodiment, an output power source is used as the high-voltage power source 20, and a capacitive power source is used as the intermediate-voltage power source 30. The capacity-type power supply has a higher energy density than the output-type power supply, and has a battery capacity, that is, a maximum electric power that can be stored. The output type power supply has a higher output density than the capacitive type power supply and a maximum output larger than that of the capacitive type power supply.

  The output voltage of the high voltage power supply 20 is higher than the output voltage of the medium voltage power supply 30. Specifically, the output voltage of the high-voltage power supply 20 is, for example, a voltage exceeding 100V, and the output voltage of the medium-voltage power supply 30 is, for example, about several tens of volts, specifically, a voltage of about 48V. As the high-voltage power supply 20, for example, a lithium ion capacitor (LiC) can be used, and as the medium-voltage power supply 30, for example, a lithium ion secondary battery (LiB) can be used.

  The power supply system 10 includes a power converter 40 that connects the high-voltage power supply 20 and the intermediate-voltage power supply 30 in a transformable manner in order to exchange DC power between the high-voltage power supply 20 and the intermediate-voltage power supply 30. Yes. In the present embodiment, as the power converter 40, bidirectional insulation that electrically transforms the high-voltage power supply 20 and the intermediate-voltage power supply 30 and connects the high-voltage power supply 20 and the intermediate-voltage power supply 30 in a transformable manner. Type DCDC converter is used. Specifically, the power converter 40 is configured to provide power between the intermediate pressure part 41 and the high pressure part 42 while electrically insulating the intermediate pressure part 41, the high pressure part 42, and the intermediate pressure part 41 and the high pressure part 42. A transformer 43 for transmission is provided. The intermediate pressure part 41 and the high pressure part 42 include a switching element. The voltage of the intermediate pressure part 41 is, for example, generally in the range of 24 to 60V, specifically 48V. The voltage of the high voltage unit 42 is, for example, in the range of more than 60V to several hundreds V, and usually exceeds 100V. Since the bidirectional insulation type DCDC converter is well known, its detailed description is omitted.

  The power converter 40 boosts the output voltage of the intermediate-voltage power supply 30 by operating the switching element and applies it to the high-voltage power supply 20 to perform a boosting operation for supplying power from the intermediate-voltage power supply 30 to the high-voltage power supply 20. . The power converter 40 performs a step-down operation of supplying power from the high-voltage power supply 20 to the intermediate-voltage power supply 30 by stepping down the output voltage of the high-voltage power supply 20 by applying the switching element and applying it to the intermediate-voltage power supply 30. .

  The power supply system 10 includes a chopper-type step-down converter 44 that steps down the output voltage of the medium-voltage power supply 30 and applies it to the auxiliary load 50. For example, a voltage of about 14 V is applied to the auxiliary load 50. In the present embodiment, the auxiliary load 50 includes an electric power steering device, a power window device, a blower, a fan, and the like. Note that a low-voltage power supply (not shown) having an output voltage lower than that of the medium-voltage power supply 30 can be a power supply source of the auxiliary load 50. In the present embodiment, it is assumed that the step-down converter 44 is integrated with the power converter 40.

  The vehicle includes an inverter 60 and a motor generator 71 as a drive device 70 connected to the inverter 60 as a high-voltage load. Inverter 60 exchanges power with high-voltage power supply 20. The motor generator 71 is a driving power source for the vehicle. As the motor generator 71, for example, a three-phase synchronous machine can be used. During the power running operation of the motor generator 71, an AC voltage is applied to the motor generator 71 from the inverter 60. During the regenerative operation of the motor generator 71, the electric power generated by the motor generator 71 is supplied to the high voltage power source 20 via the inverter 60, and further supplied to the intermediate voltage power source 30 via the power converter 40. . Note that a boost converter may be provided between the inverter 60 and the high-voltage power supply 20.

  The above-described power supply system 10 is configured to use the intermediate-voltage power supply 30 that is the power supply with the larger maximum power amount that can be stored as the main power supply for the high-voltage load and the auxiliary load 50. According to this configuration, power is supplied from the medium-voltage power supply 30 to the high-voltage load provided in the high-voltage system that is electrically insulated from the low-voltage system provided with the medium-voltage power supply 30 as necessary.

  The vehicle further includes an engine 72 as a driving device 70 serving as a driving power source. The power generated by the motor generator 71 and the engine 72 is transmitted to the drive wheels of the vehicle. The vehicle includes a braking device 90 that applies a braking force to the wheels by a friction brake.

  The vehicle includes a high-pressure temperature detector 81 that detects the temperature of the high-voltage power supply 20 and an intermediate-pressure temperature detector 82 that detects the temperature of the intermediate-voltage power supply 30. The vehicle includes a vehicle speed detection unit 83 that detects the vehicle speed, a current detection unit 84 that detects a current flowing through the motor generator 71, and a rotation angle detection unit 85 that detects the rotation angle of the rotor of the motor generator 71. As the vehicle speed detection unit 83, for example, a wheel speed sensor can be used, and as the rotation angle detection unit 85, for example, a resolver can be used. The detection value of each detection unit is input to the in-vehicle control device 80.

  The control device 80 controls the power converter 40, the step-down converter 44, the auxiliary load 50, the inverter 60, and the engine 72. Specifically, for example, control device 80 operates inverter 60 to control the torque of motor generator 71 to the target torque.

  Actually, a control device is individually provided for each of the power converter 40, the auxiliary load 50, the inverter 60, the engine 72, and the like. In the present embodiment, the point that the control devices are individually provided is not a main part, and for convenience, these control devices are illustrated as a single control device 80.

  The control device 80 performs a charge / discharge process in which power is exchanged between the high-voltage power supply 20 and the intermediate-voltage power supply 30. Hereinafter, this process will be described.

  FIG. 2 is a flowchart showing the procedure of the charge / discharge process. This process is repeatedly executed by the control device 80 at a predetermined cycle, for example. In the present embodiment, the control device 80 includes a gradient determination unit, a selection unit, an operation unit, and a power generation control unit. In the following description, basically, the sign of power in the direction from the auxiliary machine load 50 side to the motor generator 71 side is positive, and the sign of power in the opposite direction is negative.

  In this series of processing, first, in step S10, the medium voltage charge amount ELr that is the current charge amount of the medium voltage power supply 30 is estimated. The medium voltage charge amount ELr corresponds to so-called SOC. In addition, since the well-known thing can be used for the estimation method of charge amount, the detailed description is abbreviate | omitted.

  In subsequent step S11, based on the estimated intermediate voltage charge amount ELr and the temperature TL of the intermediate voltage power supply 30 detected by the intermediate pressure temperature detector 82, the output limit value PLout of the intermediate voltage power supply 30 and the intermediate voltage power supply An input limit value PLin of 30 is calculated. The output limit value PLout is the upper limit power that can be output per unit time from the medium voltage power supply 30, and the input limit value PLin is the upper limit power that can be input to the intermediate voltage power supply 30 per unit time. In the present embodiment, regarding the input / output power PL of the intermediate voltage power supply 30, a case where the medium voltage power supply 30 is discharged is represented by a positive value, and a case where the medium voltage power supply 30 is charged is represented by a negative value. For this reason, the output limit value PLout is a value of 0 or more, and the input limit value PLin is a value of 0 or less.

  In the present embodiment, the input / output limit values PLin and PLout are calculated using a map in which the input / output limit values PLin and PLout associated with the medium voltage charge amount ELr and the temperature TL are defined. Here, the relationship between the input / output limit values PLin and PLout and the intermediate voltage charge amount ELr is as shown in FIG. Specifically, the output limit value PLout is set to 0 when the intermediate voltage charge amount ELr is equal to or less than the intermediate pressure lower limit value ELmin that is the lower limit value of the control range. Thereby, the overdischarge of the medium voltage power supply 30 is prevented. On the other hand, when the medium voltage charge amount ELr is larger than the medium pressure lower limit value ELmin, the output limit value PLout is set to a value larger than zero. Specifically, when the medium voltage charge amount ELr is larger than the medium pressure lower limit value ELmin, the output limit value PLout is set to a larger value as the medium voltage charge amount ELr is larger. The intermediate pressure lower limit value ELmin may be set to a value larger than the allowable lower limit value of the intermediate voltage charge amount capable of maintaining the reliability of the intermediate voltage power supply 30, for example.

  The input limit value PLin is set to 0 when the medium voltage charge amount ELr is equal to or greater than the medium voltage upper limit value ELmax that is the upper limit value of the control range. Thereby, the overcharge of the intermediate voltage power supply 30 is prevented. When the medium voltage charge amount ELr is less than the medium voltage upper limit value ELmax, the input limit value PLin is set to a value smaller than zero. Specifically, when the medium voltage charge amount ELr is less than the medium pressure upper limit value ELmax, the input limit value PLin is set to a smaller value as the medium voltage charge amount ELr is smaller. The medium pressure upper limit value ELmax may be set to a value smaller than the allowable upper limit value of the medium voltage charge amount capable of maintaining the reliability of the medium voltage power supply 30, for example.

  Returning to the description of FIG. 2, in the subsequent step S <b> 12, the high-voltage charge amount EHr that is the current charge amount of the high-voltage power supply 20 is estimated. The high voltage charge amount EHr corresponds to so-called SOC. In addition, since the well-known thing can be used for the estimation method of charge amount, the detailed description is abbreviate | omitted.

  In the subsequent step S13, the output limit value PHout of the high-voltage power supply 20 and the input limit value of the high-voltage power supply 20 based on the estimated high-voltage charge amount EHr and the temperature TH of the high-voltage power supply 20 detected by the high-voltage temperature detector 81. PHin is calculated. The output limit value PHout is the upper limit power that can be output from the high-voltage power supply 20 per unit time, and the input limit value PHin is the upper limit power that can be input to the high-voltage power supply 20 per unit time. In the present embodiment, regarding the input / output power PH of the high-voltage power supply 20, a case where the high-voltage power supply 20 is discharged is represented by a positive value, and a case where the high-voltage power supply 20 is charged is represented by a negative value. For this reason, the output limit value PHout is a value of 0 or more, and the input limit value PHin is a value of 0 or less.

  In the present embodiment, the input / output limit values PHin and PHout are calculated using a map in which the input / output limit values PHin and PHout associated with the high-voltage charge amount EHr and the temperature TH are defined. Here, the relationship between the input / output limit values PHin and PHout and the high-voltage charge amount EHr is as shown in FIG. Note that the calculation method of the input / output limit values PHin and PHout of the high-voltage power supply 20 is the same as the calculation method of the input / output limit values PLin and PLout of the medium-voltage power supply 30, and thus detailed description thereof is omitted. FIG. 4 shows a high pressure lower limit value EHmin, which is a lower limit value of the control range of the high voltage charge amount EHr, and a high voltage upper limit value EHmax, which is an upper limit value of the control range of the high voltage charge amount EHr. The high voltage lower limit value EHmin may be set to a value larger than the allowable lower limit value of the high voltage charge amount that can maintain the reliability of the high voltage power supply 20, for example. The high voltage upper limit value EHmax is, for example, the reliability of the high voltage power supply 20 May be set to a value smaller than the allowable upper limit value of the high-voltage charge amount capable of maintaining the above.

  Returning to the description of FIG. 2, in the subsequent step S <b> 14, the medium-voltage side required power PLreq indicating the charge / discharge request of the medium-voltage power supply 30 is calculated. The medium-voltage-side required power PLreq indicates an input / output request according to the medium-voltage charge amount ELr. Hereinafter, a method of calculating the intermediate pressure side required power PLreq will be described with reference to FIG.

  In FIG. 5, the medium voltage charge ELr corresponding to SOC = 0% of the medium voltage power supply 30 is EL0, and the medium voltage charge ELr corresponding to SOC = 100% is EL100. Further, the absolute value of the maximum output of the auxiliary machine load 50 is Pomax, and the required duration of the maximum output of the auxiliary machine load 50 is TC. In the present embodiment, the output of the auxiliary load 50 is a positive value when the power is consumed from outside.

  The minimum value MINLd and the maximum value MAXLd of the medium voltage charge amount ELr that can maintain the driving of the auxiliary load 50 are expressed by the following equations (eq1) and (eq2).

中圧充電量ＥＬｒが最小値ＭＩＮＬｄを下回る場合、中圧電源３０の充電を要求すべく中圧側要求電力ＰＬｒｅｑを負の値とし、中圧充電量ＥＬｒが最大値ＭＡＸＬｄを上回る場合、中圧電源３０の放電を要求すべく中圧側要求電力ＰＬｒｅｑを正の値とする。一方、中圧充電量ＥＬｒが最小値ＭＩＮＬｄ以上であってかつ最大値ＭＡＸＬｄ以下である場合、中圧側要求電力ＰＬｒｅｑを０とする。なお、上記最小値ＭＩＮＬｄは、例えば中圧下限値ＥＬｍｉｎ以上の値に設定され、上記最大値ＭＡＸＬｄは、例えば中圧上限値ＥＬｍａｘ以下の値に設定されればよい。

When the intermediate voltage charge amount ELr is lower than the minimum value MINLd, the intermediate voltage power requirement PLreq is set to a negative value to request charging of the intermediate voltage power source 30, and when the intermediate voltage charge amount ELr exceeds the maximum value MAXLd, the intermediate voltage power source In order to request 30 discharges, the medium pressure side required power PLreq is set to a positive value. On the other hand, when the medium voltage charge amount ELr is not less than the minimum value MINLd and not more than the maximum value MAXLd, the medium voltage side required power PLreq is set to zero. The minimum value MINLd may be set to a value equal to or higher than the intermediate pressure lower limit value ELmin, for example, and the maximum value MAXLd may be set to a value equal to or lower than the intermediate pressure upper limit value ELmax, for example.

  Returning to the description of FIG. 2, in the subsequent step S15, the output limit value PHout of the high-voltage power supply 20, the output limit value PLout of the intermediate-voltage power supply 30, and the auxiliary output Po that is the current input / output of the auxiliary load 50 are obtained. By adding, the output guard value PSout is calculated. Further, the input guard value PSin is calculated by adding the input limit value PHin of the high-voltage power supply 20, the input limit value PLin of the medium-voltage power supply 30, and the auxiliary machine output Po.

  In the subsequent step S16, the required transformation power PDreq, which is a required value of the exchanged power between the high-voltage power supply 20 and the intermediate-voltage power supply 30 via the power converter 40, is calculated. The present embodiment is characterized in that the required transformation power PDreq is calculated according to the gradient state of the traveling road surface of the vehicle.

  FIG. 6 shows a procedure for calculating the required transformation power PDreq.

  In this series of processing, in steps S100 to S102, S105, it is determined whether the traveling road surface is an ascending slope or a descending slope. Specifically, first, in step S100, the disturbance power Pdext is estimated by subtracting the braking / driving power Pdobs from the acceleration / deceleration power Pvobs. The acceleration / deceleration power Pvobs is a time change rate of the kinetic energy of the vehicle. The braking / driving power Pdobs is the power applied to the driving wheels from the driving device 70 and the braking device 90. In the present embodiment, the acceleration / deceleration power Pvobs and the braking / driving power Pdobs are estimated as follows.

  A method for estimating the acceleration / deceleration power Pvobs will be described. First, the acceleration / deceleration power Pvobs is estimated based on the vehicle speed Vv detected by the vehicle speed detection unit 83. Specifically, the acceleration / deceleration power Pvobs is estimated as in the following equation (eq3) by integrating the vehicle acceleration calculated from the vehicle mass Mv, the vehicle speed Vv, and the vehicle speed Vv.

なお、加減速パワーＰｖｏｂｓの推定に用いる車両質量Ｍｖは、以下の手法により取得すればよい。詳しくは例えば、車輪を懸架するサスペンションの作用荷重を検出する車載荷重検出部の検出値に基づいて車両質量Ｍｖを算出することにより、車両質量Ｍｖを取得してもよい。また例えば、制御装置８０の記憶部としてのメモリに車両質量Ｍｖが予め記憶され、メモリから車両質量Ｍｖを読み出すことにより車両質量Ｍｖを取得してもよい。

In addition, what is necessary is just to acquire the vehicle mass Mv used for estimation of the acceleration / deceleration power Pvobs with the following method. Specifically, for example, the vehicle mass Mv may be acquired by calculating the vehicle mass Mv based on the detection value of the in-vehicle load detection unit that detects the applied load of the suspension that suspends the wheel. Further, for example, the vehicle mass Mv may be stored in advance in a memory as a storage unit of the control device 80, and the vehicle mass Mv may be acquired by reading the vehicle mass Mv from the memory.

  Subsequently, the braking / driving power Pdobs is estimated by the following equation (eq4).

上式（ｅｑ４）において、Ｐｍはモータジェネレータ７１が駆動輪に与えたパワーであるモータパワーを示す。本実施形態において、モータパワーＰｍは、力行運転時に正の値となり、回生運転時に負の値となる。モータパワーＰｍは、モータジェネレータ７１のトルクＴｍとモータジェネレータ７１の回転角速度ωｍとを乗算することにより推定されればよい。ここでモータジェネレータ７１のトルクＴｍは、電流検出部８４により検出された電流値に基づいて算出されればよく、モータジェネレータ７１の回転角速度ωｍは、回転角検出部８５により検出された回転角の時間微分値として算出されればよい。

In the above equation (eq4), Pm represents the motor power that is the power given to the drive wheels by the motor generator 71. In the present embodiment, the motor power Pm takes a positive value during power running operation and takes a negative value during regenerative operation. The motor power Pm may be estimated by multiplying the torque Tm of the motor generator 71 by the rotational angular velocity ωm of the motor generator 71. Here, the torque Tm of the motor generator 71 may be calculated based on the current value detected by the current detector 84, and the rotational angular velocity ωm of the motor generator 71 may be the rotational angle detected by the rotational angle detector 85. What is necessary is just to be calculated as a time differential value.

  In the above equation (eq4), Pbrk represents the braking power applied from the braking device 90 to the driving wheel. In the present embodiment, the braking power Pbrk has a value of 0 or less.

  In the above equation (eq4), Pe represents the output power of the engine 72, and k represents the drive contribution rate. In the present embodiment, the output power Pe of the engine 72 is a value of 0 or more. The drive contribution ratio k is the ratio of the power used as the driving power source of the vehicle in the output power Pe of the engine 72. If the power of the engine 72 consumed for purposes other than driving, such as power generation, is Pc, the drive contribution ratio k is represented by “(Pe−Pc) / Pe”.

  In subsequent step S101, the resistance power RL (> 0) received by the vehicle as the vehicle travels is estimated based on the vehicle speed Vv. The resistance power RL includes power resulting from wheel rolling resistance and air resistance. The resistance power RL may be estimated larger as the vehicle speed Vv is higher.

  In a succeeding step S102, it is determined whether or not a value obtained by subtracting the resistance power RL from the disturbance power Pdex is greater than a first threshold value Sth1 (> 0). This process is a process for determining whether or not the current traveling road surface is uphill. That is, on a flat road surface, the value obtained by subtracting the resistance power RL from the disturbance power Pdext is a value close to zero. On the uphill road, on the other hand, the value obtained by subtracting the resistance power RL from the disturbance power Pdext is a positive value, and the absolute value tends to increase as the upward gradient increases.

  If an affirmative determination is made in step S102, it is determined that there is an upward gradient, and the process proceeds to step S103. In step S103, it is determined whether or not the medium voltage charge amount ELr exceeds the medium pressure lower limit value ELmin.

  When an affirmative determination is made in step S103, the process proceeds to step S104, and the required transformation power PDreq is calculated so that power is supplied from the intermediate voltage power supply 30 to the high voltage power supply 20. This process is for reducing the intermediate voltage charge amount ELr by discharging the intermediate voltage power source 30 during traveling on the uphill road in preparation for regenerative power generation by the motor generator 71 on the downhill road. In the present embodiment, the required transformation power PDreq is calculated as constant power that maximizes the power conversion efficiency in the power converter 40, as shown in FIG. In the present embodiment, the required transformation power PDreq calculated in step S104 is a positive value.

  If a negative determination is made in step S102, the process proceeds to step S105, and it is determined whether or not the value obtained by subtracting the resistance power RL from the disturbance power Pdext is less than the second threshold value Sth2 (<0). This process is a process for determining whether the current traveling road surface is a downward slope. That is, on the downhill road, the value obtained by subtracting the resistance power RL from the disturbance power Pdext is a negative value, and the absolute value tends to increase as the descending slope increases.

  If an affirmative determination is made in step S105, it is determined that the slope is descending, and the process proceeds to step S106. In step S106, it is determined whether or not the intermediate pressure charge amount ELr is less than the intermediate pressure upper limit value ELmax.

  When an affirmative determination is made in step S106, the process proceeds to step S107, and the required transformation power PDreq is calculated so that power is supplied from the high-voltage power supply 20 to the intermediate-voltage power supply 30. This process is for charging the intermediate-voltage power supply 30 during traveling on the downhill road to increase the intermediate-voltage charge amount ELr in preparation for the subsequent acceleration request of the motor generator 71 on the uphill road. In the present embodiment, the required transformation power PDreq is calculated as a constant power that maximizes the power conversion efficiency in the power converter 40. In the present embodiment, the required transformation power PDreq calculated in step S107 is a negative value.

  If a negative determination is made in steps S103, S105, and S106, the process proceeds to step S108, and a process for calculating the required transformation power PDreq at the normal time is performed. Hereinafter, this process will be described with reference to FIG.

  FIG. 8 is a map in which the charge amount ratio X (= EHr / ELr), which is the ratio of the high-voltage charge amount EHr to the medium-voltage charge amount ELr, is plotted on the horizontal axis and the required transformation power PDreq is plotted on the vertical axis. As shown in the figure, when the high-voltage charge amount EHr is smaller than the medium-voltage charge amount ELr and the charge amount ratio X is smaller than the lower limit threshold value Xmin, the substation is supplied to supply power from the intermediate-voltage power supply 30 to the high-voltage power supply 20. The required power PDreq is set to a positive value. On the other hand, when the medium voltage charge amount ELr is smaller than the high voltage charge amount EHr and the charge amount ratio X is larger than the upper limit threshold value Xmax (> Xmin), the substation is supplied to supply power from the high voltage power source 20 to the medium voltage power source 30. The required power PDreq is set to a negative value. On the other hand, when the charge amount ratio X is not less than the lower limit threshold Xmin and not more than the upper limit threshold Xmax, the required transformation power PDreq is set to zero. The lower limit threshold value Xmin and the upper limit threshold value Xmax are set in advance through experiments or the like.

  Incidentally, in FIG. 6 of the present embodiment, the first threshold value Sth1 and the second threshold value Sth2 are set across 0 when the actual gradient of the traveling road surface slightly fluctuates across 0, step S104, This is to prevent the process of S107 from being executed.

  Returning to the description of FIG. 2, in the subsequent step S <b> 17, the predicted power PHreq depending on the input / output power PH of the high-voltage power supply 20 is calculated. Hereinafter, a method of calculating the predicted power PHreq will be described with reference to FIG.

  In the example shown in FIG. 9, the input / output power PH (> 0) of the high-voltage power supply 20 changes in a mountain shape so that it increases from time t1 to time t2 and decreases from time t2 to time t3. The output limit value PHout is exceeded during the straddling period. When the future required power is not predicted, the static required power PHreqs, which is a value obtained by subtracting the output limit value PHout from the input / output power PH of the high-voltage power supply 20, is indicated by the hatched area of the broken line.

  On the other hand, in the present embodiment, the predicted power PHreq that is the future required power is calculated based on the time differential value “dPH / dt” of the input / output power of the high-voltage power supply 20. In FIG. 9, the lead compensation term “α × (dPH / dt)” obtained by multiplying the power change “dPH / dt” by the adaptive factor α is a positive value in the period from time t1 to time t2, and from time t2 to time t2. It becomes a negative value in the period up to t3.

  The predicted power PHreq is calculated by the following equation (eq5).

図９の実線のハッチング領域で示すように、進み補償項に基づき算出された予測電力ＰＨｒｅｑは、静的要求電力ＰＨｒｅｑｓに対し進み側にシフトする。これにより、例えば、高圧電源２０の出力電力が出力制限値ＰＨｏｕｔを上回り、高圧電源２０の出力が不足すると予測された場合、予め中圧電源３０から高圧電源２０へと充電されるように電力変換器４０が操作される。一方、高圧電源２０の入力電力が入力制限値ＰＨｉｎを下回り、高圧電源２０の入力が過剰になると予測された場合、予め高圧電源２０から中圧電源３０へと放電されるように電力変換器４０が操作される。

As shown by the hatched area of the solid line in FIG. 9, the predicted power PHreq calculated based on the lead compensation term is shifted to the lead side with respect to the static demand power PHreqs. Thereby, for example, when it is predicted that the output power of the high-voltage power supply 20 exceeds the output limit value PHout and the output of the high-voltage power supply 20 is insufficient, the power conversion is performed so that the medium-voltage power supply 30 is charged in advance to the high-voltage power supply 20. The device 40 is operated. On the other hand, when it is predicted that the input power of the high-voltage power supply 20 is less than the input limit value PHin and the input of the high-voltage power supply 20 is excessive, the power converter 40 is discharged in advance from the high-voltage power supply 20 to the intermediate-voltage power supply 30. Is operated.

  Returning to the description of FIG. 2, in the subsequent step S18, the high-voltage side required power PIreq, which is the required power of the high-voltage load including the inverter 60, is calculated. In the present embodiment, the high-voltage side required power PIreq takes a positive value during the power running operation of the motor generator 71. The high-voltage-side required power PIreq reflects requests from the driving main system such as improvement in thermal efficiency of the engine 72 and regenerative power.

  In the subsequent step S19, the high voltage target power PItgt to be supplied to the high voltage load is calculated by the following equation (eq6). In this calculation, the upper limit on the positive side is limited by the output guard value PSout and the lower limit on the negative side is limited by the input guard value PSin with respect to the sum of the high-voltage-side required power PIreq and the medium-voltage-side required power PLreq.

続くステップＳ２０では、高圧側要求電力ＰＩｒｅｑに基づいて、電力変換器４０を介した授受電力の目標値である最終目標電力ＰＤＣｔｇｔを下式（ｅｑ７）により算出する。

In the subsequent step S20, the final target power PDCtgt, which is the target value of power exchanged via the power converter 40, is calculated by the following equation (eq7) based on the high-voltage side required power PIreq.

上式（ｅｑ７）の第１項は、高圧側要求電力ＰＩｒｅｑに対する高圧電源２０の入出力電力ＰＨの不足量の現在値を示す。

The first term of the above equation (eq7) indicates the current value of the shortage amount of the input / output power PH of the high-voltage power supply 20 with respect to the high-voltage side required power PIreq.

  In the subsequent step S21, the switching element of the power converter 40 is operated so as to control the exchange power between the high-voltage power supply 20 and the intermediate-voltage power supply 30 via the power converter 40 to the final target power PDCtgt.

  According to the embodiment described in detail above, the following effects can be obtained.

  Electric power is supplied from the intermediate voltage power source 30 to the high voltage power source 20 until the intermediate voltage charge amount ELr decreases and reaches the intermediate voltage lower limit value ELmin over a period in which it is determined that the traveling road surface is an upward gradient. The power converter 40 was operated as described above. Thereby, the intermediate voltage charge amount ELr can be reduced in preparation for the subsequent regenerative power generation on the downhill road. Further, power is supplied from the high-voltage power supply 20 to the intermediate-voltage power supply 30 until the intermediate-voltage charge amount ELr rises and reaches the intermediate-pressure upper limit value ELmax over a period in which the traveling road surface is determined to have a downward slope. The power converter 40 was operated as described. As a result, the intermediate voltage charge amount ELr can be increased in preparation for powering operation of the motor generator 71 on the subsequent uphill road. As described above, according to the present embodiment, the high-voltage charge amount EHr and the intermediate-voltage charge amount ELr can be appropriately adjusted and the high-voltage power supply 20 and the intermediate-voltage power supply 30 can be effectively used in preparation for the change in the gradient state of the traveling road surface. . Thereby, by reducing the charge amount of the intermediate-voltage power supply 30, it becomes possible to sufficiently accept the regenerative power on the next downward slope, and the fuel efficiency of the vehicle can be improved.

  The power converter 40 is configured such that power is supplied from the intermediate-voltage power supply 30 to the high-voltage power supply 20 at a constant power that maximizes the power conversion efficiency in the power converter 40 over a period when it is determined that the slope is an uphill. Was operated. Further, power conversion is performed so that power is supplied from the high-voltage power supply 20 to the intermediate-voltage power supply 30 with constant power that maximizes the power conversion efficiency in the power converter 40 over a period when it is determined that the slope is descending. The vessel 40 was operated. Thereby, the loss in the power converter 40 can be minimized.

(Other embodiments)
The above embodiment may be modified as follows.

  As shown in FIG. 10, the high voltage power supply 21 may be a capacitive power supply, and the medium voltage power supply 31 may be an output power supply. In FIG. 10, the same components as those shown in FIG. 1 are given the same reference numerals for the sake of convenience.

  The method for determining whether the road surface gradient is an upward gradient or a downward gradient is not limited to that exemplified in the above embodiment. For example, a vehicle may be provided with a gradient sensor that detects a road surface gradient, and it may be determined whether the vehicle is an ascending gradient or a descending gradient based on the detection result of the gradient sensor.

  -Power may be supplied from the medium-voltage power supply 30 to the high-voltage power supply 20 at an operating point where the power conversion efficiency in the power converter 40 does not become maximum over a period in which it is determined that the slope is ascending. The same applies to the period determined to have a downward slope.

  -The power converter 40 is not restricted to what was illustrated to the said embodiment.

  In the above-described embodiment, the output voltages of the high-voltage power supply 20 and the medium-voltage power supply 30 that are the two power supplies provided in the power supply system 10 are different from each other. In this case, a non-insulated DCDC converter that does not electrically insulate between the two power sources may be used as the power converter.

  By adopting a configuration where the power converter 40 steps down to a low pressure, the step-down converter 44 may be eliminated, and the intermediate voltage power supply 30 may be a low voltage power supply.

  The vehicle is not limited to a hybrid vehicle, and may be a vehicle having another power generation source such as a vehicle having a fuel cell. The vehicle may be a vehicle that includes only a motor generator as a driving power source.

  DESCRIPTION OF SYMBOLS 20 ... High voltage power supply, 30 ... Medium voltage power supply, 40 ... Power converter, 50 ... Auxiliary load, 71 ... Motor generator, 80 ... Control apparatus.

Claims (8)

A first power source (20; 21) for transferring electric power to and from a rotating electrical machine (71) serving as an in-vehicle main unit;
A second power source (30; 31) that exchanges power with a load (50) other than the rotating electrical machine;
A power converter (40) that connects the first power source and the second power source so as to be capable of transmitting power in both directions, and is applied to a vehicle.
One of the first power source and the second power source is a capacitive power source, the other is an output power source, and the capacitive power source has a larger amount of power that can be stored than the output power source, The output type power source has a larger output than the capacitive type power source,
A gradient determination unit (80) for determining whether the gradient of the road surface on which the vehicle travels is an ascending gradient or a descending gradient;
A selection unit (80) that selects one of the first power source and the second power source as a source power source and selects the other as a source power source based on a determination result by the gradient determination unit;
A power control apparatus comprising: an operation unit (80) that operates the power converter so that power is supplied from the supply source power source to the supply destination power source. The selection unit selects the second power source as the source power source, and selects the first power source as the destination power source when the gradient determination unit determines that the slope is an upslope.
When the gradient determination unit determines that the operation unit is an upward gradient, the operation unit switches from the second power source to the first power source until the charge amount of the second power source reaches a lower limit value of the control range. The power supply control apparatus of Claim 1 which operates the said power converter so that electric power is supplied. The selection unit selects the first power source as the source power source, and selects the second power source as the source power source when the gradient determination unit determines that the slope is a downward slope,
When the gradient determination unit determines that the operation unit has a downward gradient, the operation unit changes from the first power supply to the second power supply until the charge amount of the second power supply reaches the upper limit value of the control range. The power supply control device according to claim 1, wherein the power converter is operated so that electric power is supplied.   The said operation part operates the said power converter so that electric power is supplied from the said source power supply to the said destination power supply with the fixed electric power in which the power conversion efficiency in the said power converter becomes the maximum. The power supply control device according to any one of the above.   5. The power generation control unit according to claim 1, further comprising: a power generation control unit that generates at least power to be supplied to the first power source by causing the rotating electrical machine to generate regenerative power using kinetic energy of the vehicle as an input. Power supply control device. The second power source has a lower output voltage than the first power source,
6. The power supply control device according to claim 1, wherein the power converter is configured to connect the first power supply and the second power supply so as to allow bidirectional transformation.   The power converter connects the first power source and the second power source so as to be capable of bidirectional transformation while electrically insulating the first power source and the second power source. The power supply control device described. The first power source is the output type power source;
The power supply control device according to claim 1, wherein the second power supply is the capacitive power supply.

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