JP2007126050A - Electric power management device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control distribution of electric power supplied to each electric load properly. <P>SOLUTION: In this electric power management device for a vehicle for controlling distribution of electric power supplied to a plurality of electric loads, characteristics of performance satisfaction of electric load for supplied electric power are led through per electric load. The characteristics of performance satisfaction of each electric load are indicated by degree of performance satisfaction as a common index among the plurality of electric loads. The distribution of electric power supplied for each electric load is optimized so that a total value of degrees of performance satisfaction in each electric load becomes the maximum value by using electric power supplied from power supply as restriction conditions. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicle power management device that controls supply power distribution when power that can be supplied from a power source is distributed and supplied to a plurality of electric loads.

2. Description of the Related Art Conventionally, a vehicle distribution system equipped with a vehicle equipped with a large number of vehicle-mounted electrical loads, and including a vehicle-mounted power supply and a distribution control unit that distributes power supplied from the vehicle-mounted power supply to the vehicle-mounted electrical load individually and intermittently. In the apparatus, the power distribution control unit includes a storage unit that stores load importance level information that divides the in-vehicle electric loads into a plurality of groups according to importance, a partial power supply of a power supply system including the in-vehicle power source and the power distribution control unit Means for detecting a possible abnormality, and when the abnormality is detected, the vehicle electric load of the group having high importance is preferentially fed based on the load importance information, and the vehicle electric load of the group having low importance is detected. 2. Description of the Related Art There is known a vehicle power distribution device including a power supply control unit that interrupts power supply to a vehicle (see, for example, Patent Document 1).
JP 2002-200908 A

  In recent years, with the diversification and sophistication of vehicle functions, many electronic components (electric loads) are being mounted on vehicles. In general, the power supply mounted on a vehicle is determined such that the rated power, etc., can be supplied without any shortage to each electric load mounted on the vehicle. The power consumption mode that allows the operation to the limit allows the performance of each electric load to be maximized, but it may be inefficient, and there is also a disadvantage such as an increase in the size of the power supply. is there.

  For this reason, it is useful to control the supply power distribution to each electric load not only in the case where an abnormality occurs in the in-vehicle system as in the above-described prior art but also in the normal time. In this case, it is possible to reduce the size of the power supply, but on the other hand, the performance of each electric load must be appropriately demonstrated within the range not exceeding the power that can be supplied from the power supply. It is difficult to determine power distribution appropriately.

  Accordingly, an object of the present invention is to provide a vehicular power management apparatus that can appropriately control distribution of power supplied to each electric load.

In order to achieve the above object, a first invention provides a vehicle power management apparatus that controls supply power distribution to a plurality of electric loads.
Deriving the performance satisfaction characteristics of the electrical load relative to the supplied power for each electrical load,
Based on the state of the power source, the operation request state of each electric load, and the performance satisfaction characteristic of each electric load, the supply power distribution to each electric load is calculated.

2nd invention is the electric power management apparatus for vehicles which concerns on 1st invention,
Performance satisfaction characteristics of each electrical load are expressed as performance satisfaction as a common index among multiple electrical loads.
The power that can be supplied from the power supply is used as a constraint condition, and the supply power distribution to each electric load is optimized so that the total value of the performance satisfaction in each electric load is maximized.

3rd invention is the electric power management apparatus for vehicles which concerns on 1st or 2nd invention,
For each operation request state of each electric load, the calculated supply power distribution to each electric load is stored as an actual value, and the supply power distribution to each electric load is determined according to the stored actual power distribution value. It is characterized by determining.

4th invention is the electric power management apparatus for vehicles which concerns on 3rd invention,
Periodically, the recalculated supply power distribution is used in place of the stored actual power distribution value.

5th invention is the electric power management apparatus for vehicles which concerns on 1st or 2nd invention,
An operation request for each electric load is predicted based on the vehicle state, and a distribution of power supplied to each electric load is calculated based on the predicted operation request for each electric load.

6th invention is the electric power management apparatus for vehicles which concerns on 5th invention,
When an operation request for a predetermined electric load that consumes a large amount of power at the start of operation is predicted, the power that can be supplied from the power supply is corrected so that the power that can be supplied decreases, and the supply to each electric load is performed. The power distribution is calculated.

5th invention is the electric power management apparatus for vehicles which concerns on 1st, 2nd, or 5th invention,
Each electrical load has a power supply priority,
When the state of the power source falls below a predetermined standard, the distribution of the supply power to the remaining electric loads is calculated under a condition in which the power supply to the electric loads with low priority is cut off in advance.

  According to the present invention, by using the performance satisfaction characteristic with respect to the supply power of each electric load, the distribution of the supply power to each electric load is controlled, so that each electric load is within the range not exceeding the power that can be supplied from the power source. It is possible to appropriately exhibit the performance of.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a diagram showing a basic system configuration according to the vehicle power management apparatus of the present invention. The power management apparatus according to the present embodiment is configured with the power manager 10 as the center. The power manager 10 includes a microcomputer including a CPU, a ROM, a RAM, and the like that are connected to each other via a bus (not shown) as in a general ECU (Electronic Control Unit).

  Each electric load 20A, 20B, 20C... Is connected to the power manager 10 via an appropriate bus such as a CAN (controller area network). Each electric load 20 may be a unit of a load system composed of one or more electric load elements, or may be a unit of each electric load element in each load system. The load system includes, for example, an air conditioning system including a blower motor and a controller for controlling the air blower motor, an electric power steering system including an assist motor and a controller for controlling the assist motor, and an air bag system including a controller for controlling the squib and its driver. , And so on.

  The power manager 10 transmits the sensor information of various in-vehicle sensors, the external information acquired by the in-vehicle communication device from an external center, other vehicles, etc., and the loads of the electric loads 20A, 20B, 20C,. Information (including required power described later) and the like can be acquired.

  A generator 30 is connected to the power manager 10 via an appropriate bus. The generator 30 is typically an alternator that converts engine output energy into electrical energy. The power manager 10 instructs the power generation voltage to the generator 30 according to the traveling state of the vehicle.

  A battery manager 40 is connected to the power manager 10 via an appropriate bus. The battery manager 40 calculates the state (SOC) of the in-vehicle battery 42 based on the current value, the voltage value, the battery temperature, and the like, and periodically notifies the power manager 10. The battery 42 includes a lead battery, a lithium ion battery, a fuel cell, and the like, and may be a combination of two or more batteries (for example, a lead battery and a lithium ion battery in a two-power supply system). The battery 42 constitutes a power source for the electric loads 20A, 20B, 20C,.

  As will be described in detail below, the power manager 10 controls the supply power distribution to the electric loads 20A, 20B, 20C,. Here, the supply power distribution refers to the electric loads 20A, 20B, 20C,... With respect to the power supplied from the power source (in this example, the power supplied from the battery 42 without considering the generator 30 for simplicity). This represents the ratio of each supply power to. The control of the supply power distribution by the power manager 10 can be realized mechanically by connecting / cutting off the power supply path to each of the electric loads 20A, 20B, 20C,. By changing the operation instruction value or control target value for each of the electric loads 20A, 20B, 20C,..., It can be easily realized electrically.

  In this embodiment, as will be described in detail below, an evaluation function representing performance satisfaction, which is an index that is commonly evaluated among a plurality of electric loads, is introduced, and the relative importance between the electric loads is expressed as performance satisfaction. , The distribution of power supplied to each electric load is optimally controlled.

  Hereinafter, for ease of understanding of the present embodiment, three electric loads 20A, 20B, and 20C will be described as an example, and the electric load 20A is a brake system (hereinafter also referred to as “ECB system 20A”). The electrical load 20B is a power steering system (hereinafter also referred to as “PS system 20B”), and the electrical load 20C is a seat heater (hereinafter also referred to as “seat heater 20C”).

  2 shows an example of the evaluation function of the ECB system 20A, FIG. 3 shows an example of the evaluation function of the PS system 20B, and FIG. 4 shows an example of the evaluation function of the seat heater 20C. In each figure, the horizontal axis represents power supply or power consumption [W] to the electric load, and the vertical axis represents performance satisfaction. The performance satisfaction is an index common to the three electrical loads 20A, 20B, and 20C (that is, a standardized index), and the maximum performance satisfaction 1 is that the performance of the electrical load is maximized. Therefore, the minimum performance satisfaction of 0 means that the performance of the electric load is not exhibited at all.

  Here, the evaluation function represents the performance satisfaction characteristic of the electric load with respect to the supplied power, but it is not the performance satisfaction characteristic when the performance of only the electric load is taken alone, but the electric load in the entire vehicle. This represents the performance satisfaction characteristics when the performance of the system is captured. In other words, the evaluation function represents the relative importance between the electric loads with an emphasis on the function of the vehicle as a whole (especially traveling performance). Note that the evaluation function is not always a continuous function as shown in the figure, and may be a discontinuous function depending on the electric load.

As shown in FIG. 2A, the evaluation function F _B (W _B ) of the ECB system 20A is the maximum performance satisfaction when the supplied power W _B [W] to the ECB system 20A is the power value W _B0 [W]. degree 1, and the performance satisfaction in the supply power W _B before and after is set steep function rapidly decreases. The power value W _B0 corresponds to power consumption (hereinafter referred to as “required power W _B0 ”) when the ECB system 20A operates under the condition that there is no restriction on power supply from the power source.

In this case, for the ECB system 20A, when the supply power W _B is different from the required power W _B0, so that the performance satisfaction decreases rapidly from a maximum value 1. This means that if the required power is not supplied to the ECB system 20A, the performance satisfaction of the ECB system 20A is significantly reduced. In the case where the supply power W _B exceeds the required power W _B0 also consume the performance satisfaction is rapidly reduced from the maximum value of 1, the supply power W _B exceeds the required power W _B0 by ECB system 20A It means impossible.

Since the required power W _B0 changes according to the operation mode of the ECB system 20A, the evaluation function F _B (W _B ) of the ECB system 20A changes as the required power W _B0 changes. That is, precisely, the evaluation function of the ECB system 20A is represented by F _B (W _B , W _B0 ) by two parameters. 2 (A) and 2 (B) show evaluation functions for different operating modes of the ECB system 20A, respectively. Specifically, FIG. 2 (A) is more demanding than the case of FIG. 2 (B). The evaluation function when the electric power W _B0 is large (typically, the brake operation amount is large) is shown. The evaluation function basically translates in the horizontal axis direction while substantially maintaining the above-described shape (the steep convex shape centered on the required power W _B0 ) as the required power W _B0 decreases. It's okay. However, if the required power W _B0 is smaller than a predetermined reference value (for example, if the brake operation amount is smaller than a predetermined reference value), as shown in Fig. 2 (B), the supply power W _B is the required power W _B0 Sometimes the maximum performance satisfaction becomes 1, and as the supplied power W _B becomes smaller than the required power W _B0 , the performance satisfaction gradually decreases to a predetermined value (eg, 0.7) of zero or more. There may be. This is because it is assumed that the required braking force is not so high when the brake operation amount is not so large.

  Regarding the evaluation function of the ECB system 20A, from the same viewpoint as described above, different evaluation functions are defined according to the brake operation mode using two or more parameters (for example, brake operation amount, operation speed, etc.) related to the brake operation. May be.

As shown in FIG. 3A, the evaluation function F _S (W _S ) of the PS system 20B satisfies the maximum performance when the supplied power W _S [W] to the PS system 20B is a power value W _S0 [W]. When the supplied power W _S becomes larger than the power value W _S0 , the performance satisfaction decreases rapidly, and the performance satisfaction gradually decreases to zero as the supplied power W _S becomes smaller than the power value W _S0 . And decrease. The power value W _S0 corresponds to the power consumption (hereinafter referred to as “required power W _S0 ”) when the PS system 20B is operated under the condition that there is no restriction on the power supply from the power source.

In this case, with respect to the PS system 20B, when the supplied power W _S deviates from the required power W _S0 and decreases, the performance satisfaction gradually decreases from the maximum value 1 to zero. This point is different from the performance satisfaction characteristic of the ECB system 20A described above, whereas the PS system 20B is related to the running performance (bending performance) of the vehicle, but is not an indispensable element for securing the bending performance. This is because the ECB system 20A is an indispensable element for ensuring the running performance (stopping performance) of the vehicle.

Similarly, since the required power W _S0 changes according to the operating mode of the PS system 20B, the evaluation function F _S (W _S ) of the PS system 20B changes as the required power W _S0 changes. That is, precisely, the evaluation function of the PS system 20B is represented by F _S (W _S , W _S0 ). 3 (A) and 3 (B) show evaluation functions for different operating modes of the PS system 20B, respectively. Specifically, FIG. 3 (A) is more demanding than the case of FIG. 3 (B). An evaluation function when the electric power _WS0 is large (typically, the steering operation speed or the operation torque is large) is shown. Evaluation function shown in FIG. 3 (B), similarly to the evaluation function shown in FIG. 3 (A), maximum performance satisfaction becomes 1 when the supply power W _S is the required power W _S0, the supply power W _S is the required power as W _S0 is smaller than, it decreases to performance satisfaction gradually zero.

As shown in FIG. 4, the evaluation function F _H (W _H ) of the seat heater 20C is the maximum performance satisfaction level 1 when the power supply W _H [W] supplied to the seat heater 20C is the power value W _H0 [W]. , when the supply power W _H is greater than the power value W _H0, performance satisfaction decreases sharply, as the supply power W _H is smaller than the power value W _H0, performance satisfaction gradually decreases. The power value W _H0 corresponds to the power consumption (hereinafter referred to as “required power W _H0 ”) when the seat heater 20C is operated under the condition that the power supply from the power source is not limited.

In this case, for the seat heater 20C, when reduced to deviate supply power W _H from the required power W _H0, from the maximum value 1 performance satisfaction decreases with a gentle slope, the supply power W _H becomes zero However, the performance satisfaction does not become zero (for example, the performance satisfaction decreases only to about 0.7). This is different from the performance satisfaction characteristic of the PS system 20B described above because the seat heater 20C is an element related to passenger comfort that is not related to the running performance of the vehicle.

Similarly, since the required power W _H0 changes according to the operating mode of the seat heater 20C, the evaluation function F _H (W _H ) of the seat heater 20C changes as the required power W _H0 changes. More specifically, the evaluation function of the seat heater 20C is expressed by F _H (W _H , W _H0 ). 4A and 4B show evaluation functions for different operation modes of the seat heater 20C, respectively. Specifically, FIG. 4A is more demanding than the case of FIG. 4B. The evaluation function when the electric power W _B0 is large (typically, the set temperature is high) is shown. Similar to the evaluation function shown in FIG. 4A, the evaluation function shown in FIG. 4B has the maximum performance satisfaction level 1 when the supplied power W _H is the required power W _H0 [W], and the supplied power W _H Is smaller than the required power W _H0 , the performance satisfaction gradually decreases to, for example, 0.8.

  As described above, according to the present embodiment, the function / characteristic / importance level, etc. are given to the electric loads 20A, 20B, 20C,. A plurality of electric loads having different values can be relatively evaluated by a common index (performance satisfaction).

  The power manager 10 appropriately determines supply power distribution to each electric load using the evaluation function (performance satisfaction characteristic) of each electric load described above. Hereinafter, this specific example will be described with reference to FIGS.

FIG. 5 shows an example of the evaluation function F _P (W _P ) of the battery 42. In FIG. 5, the horizontal axis represents power W _P supplied from the battery 42 (hereinafter referred to as “battery supply power W _P ”) [W], and the vertical axis represents performance satisfaction. Battery supply electric power _{W P} is each electrical load 20A, 20B, corresponding to the total power consumption of 20C. The performance satisfaction of the battery 42 is different from the performance satisfaction of the electric load described above, and is set to be higher as the load of the battery 42 is smaller (that is, as the battery supply power is smaller).

Specifically, the evaluation function F _{P (W P)} of the battery 42, as shown in FIG. 5 (A), maximum performance satisfaction becomes 1 battery supply electric power W _P is from zero to a predetermined value alpha, the battery When the supply power W _P is greater than the predetermined value alpha, performance satisfaction decreases to rapidly zero. Here, the evaluation function F _P (W _P ) of the battery 42 is set according to the state of charge (SOC) of the battery 42. In other words, the evaluation function of the battery 42 is expressed accurately as F _P (W _P , SOC). FIG. 5A and FIG. 5B each show an evaluation function for the state of charge of different batteries 42. Specifically, FIG. 5A shows an evaluation function when the SOC is 100%. FIG. 5B shows an evaluation function when the SOC is 70%. In the evaluation function shown in FIG. 5B, the predetermined value α is set smaller than that in the evaluation function shown in FIG. 5A, and, in the other cases, similarly, the maximum performance is obtained from zero to the predetermined value α. When the satisfaction level is 1 and the battery power supply is greater than the predetermined value α, the performance satisfaction level is rapidly reduced to zero.

  FIG. 6 is a flowchart of a process for determining supply power distribution for each electric load by the power manager 10.

  In step 100, the power manager 10 grasps the state of charge (SOC) of the battery 42. Note that the SOC of the battery 42 does not change greatly in a short time such as the cycle of this processing routine (the calculation cycle by the power manager 10), so the processing of this step 100 is performed only for the first time or periodically with a relatively long cycle. May be executed.

In step 110, the power manager 10 requests operation of each of the electric loads 20A, 20B, and 20C through communication with each of the electric loads 20A, 20B, and 20C (an ECU that controls the electric load 20C). The state, that is, the required powers W _B0 , W _S0 , and W _H0 of the electric loads 20A, 20B, and 20C are grasped. Each electric load 20A, 20B, 20C is normally arbitrarily supplied with power from the battery 42 without intervention (power supply limitation) by the power manager 10. That is, each electric load 20A, 20B, 20C operates freely according to an operation instruction from each ECU. For example, when the switch is turned on, the seat heater 20C operates according to the set temperature (indicated value from the controller) that has been set.

In step 120, the power manager 10 evaluates the evaluation functions F _B (W _B ), F _S (W _S ), and F _H (F _H ) according to the required powers W _B0 , W _S0 , and W _H0 of the electric loads 20A, 20B, and 20C. W _H ) is read from the predetermined memory, and the evaluation function F _P (W _P ) of the battery 42 corresponding to the SOC of the battery 42 is read from the predetermined memory.

In step 130, the power manager 10 determines the supply power distribution W _B / W _P , W _S / W _P , and W _H / W _P for each electric load by an optimization calculation. Specifically, the power manager 10 sets the objective function Ft = F _B (W _B ) + F _S (W _S ) + F _H (W _H ) + F _P (W _P ) as W _P = W _B + F _S + F _H. such that maximum, the electric load 20A, 20B, supply power _W B for _20C, W S, the _{W H} seek. The power manager 10 determines supply power distribution W _B / W _P , W _S / W _P , and W _H / W _P for each electric load based on the supply power W _B , W _S , and W _H thus obtained.

In step 140, the power manager 10 sets the determined supply power distributions W _B / W _P , W _S / W _P , and W _H / W _P as necessary for each of the electric loads 20A, 20B, and 20C. An instruction is transmitted to the ECU. In other words, the power manager 10 restricts the operation of the electric load so that the supply power of the optimum value is supplied to the electric load in which the supply power not corresponding to the required power is calculated as the optimum value. This can be realized mechanically by connecting / cutting off the power supply path to the electric load by a relay, but by changing the operation instruction value for the electric load (for example, to the seat heater 20C) On the other hand, by setting a variable upper limit value for the energization current and lowering the upper limit value), this can be easily realized electrically.

  The processing routine of steps 100 to 140 is repeated at predetermined intervals (for example, until the ignition switch is turned off).

Referring now to FIG. 5 again, the evaluation function F _P of the battery 42 _{(W P),} when the battery supply electric power W _P is greater than the predetermined value alpha, performance satisfaction decreases to rapidly zero. Therefore, unless the total required power (= W _B0 + W _S0 + W _H0 ) of the electric loads 20A, 20B, and 20C exceeds the predetermined value α, the objective function Ft is the required power W _{B0 of the} electric loads 20A, 20B, and 20C. , W _S0 , W _H0 , the supply power W _B , W _S , W _H is maximized (that is, W _B0 , W _S0 , W _H0 are optimum values). On the other hand, if the total required power of each of the electric loads 20A, 20B, and 20C exceeds the predetermined value α, the performance satisfaction of F _P (W _P ) decreases rapidly, so that the supplied power W _B and W _S that are obtained are reduced. , W _H will not correspond to the required power W _B0 , W _S0 , W _H0 of each electrical load 20A, 20B, 20C. This means that supply power as required is not supplied to a certain electrical load. As described above, according to the present embodiment, when the total required power becomes a large value exceeding the allowable limit of the battery 42, the supply power distribution to each electric load is distributed while appropriately protecting the battery 42. Can be optimized.

In addition, as is clear from the characteristics of the evaluation function F _P (W _P ) of the battery 42 described above, this optimization method uses the electric power that can be supplied from the battery 42 as a constraint condition, and each electric load 20A, 20B, 20C. This is substantially equivalent to finding an optimal solution that maximizes the total value of performance satisfaction. Therefore, alternatively, the power manager 10 has a constraint that W _P = W _B + F _S + F _H and W _P = W _B + F _S + F _H <α (where α is variable depending on the SOC of the battery 42). Under the conditions, the supplied power W _B , W _{S to} each of the electric loads 20A, 20B, 20C is such that the objective function Ft = F _B (W _B ) + F _S (W _S ) + F _H (W _H ) is maximized. , may be obtained _{W H.} Also in this case, it is possible to optimize the supply power distribution to each electric load as long as the total required power does not exceed the allowable limit of the battery 42. In this alternative example, it is not necessary to define the evaluation function F _P (W _P ) of the battery 42 described above, and merely determine the power (for example, α described above) that can be supplied from the battery 42 as a constraint condition. It's okay.

In the present embodiment, since the relative importance (electric power supply priority) of each electric load is reflected in the evaluation function itself, the objective function Ft = F _B (W _B ) + F _S (W _S ) + F _H (W _H ) + F _P (W _P ) or objective function Ft = F _B (W _B ) + F _S (W _S ) + F _H (W _H ) It is also possible to assign a weighting coefficient. For example, when the total required power greatly exceeds a predetermined value α or the SOC of the battery 42 falls below a predetermined value, the priority is set by setting the weighting coefficient for F _H (W _H ) to zero. It is also possible to form a condition in which the power supply to the low electric load 20C is cut off in advance, and to optimize the distribution of the supply power to the remaining electric loads 20A and 20B under the condition.

In this embodiment, the evaluation function of each of the electric loads 20A, 20B, and 20C is the ratio of the electric power supply power consumption W [W] of the electric load to the required electric power W ₀ [W] of the electric load (= W / W ₀ ) May be defined as a parameter. In this case, based on the same concept as described above, for example, the evaluation function F _B (W _B / W _B0 ) of the ECB system 20A is obtained when the supply power W _B [W] to the ECB system 20A is the required power W _B0 [W]. maximum performance satisfaction becomes 1, performance satisfaction in the supply power W _B before and after may be set to steep function rapidly decreases. In this case, it is not necessary to define a plurality of evaluation functions according to the required power W _B0 , and the memory capacity can be saved.

  Next, other preferred embodiments that can be configured on the basis of the above-described embodiments will be described in several parts.

  In the first embodiment, for each operation request state of each electric load 20A, 20B, 20C, the supply power distribution (optimum solution) to each electric load calculated as described above is stored in a predetermined memory as an actual value, According to the stored actual value of the supplied power distribution, the distribution of the supplied power to each electric load is controlled.

  FIG. 7 is a flowchart of supply power distribution determination processing realized by the power manager 10 according to the first embodiment. Detailed description of the same processing as that described with reference to FIG. 6 is omitted.

  In step 200, the power manager 10 grasps the SOC of the battery 42.

  In step 210, the power manager 10 grasps the operation request states of the electric loads 20A, 20B, and 20C through communication with the electric loads 20A, 20B, and 20C.

  In step 220, the power manager 10 determines whether or not the actual value corresponding to the grasped operation request state is stored in a predetermined memory. When the actual value is stored in the memory, the actual value is used as the supply power distribution in the current cycle (step 230). On the other hand, if the actual value is not stored in the memory, the process proceeds to step 240.

In step 240, the power manager 10 evaluates the evaluation functions F _B (W _B ), F _S (W _S ), F _H (in accordance with the required powers W _B0 , W _S0 , W _H0 of the electric loads 20A, 20B, 20C. W _H ) is read from the predetermined memory, and the evaluation function F _P (W _P ) of the battery 42 corresponding to the SOC of the battery 42 is read from the predetermined memory.

In step 250, the power manager 10 determines the supply power distribution W _B / W _P , W _S / W _P , W _H / W _P for each electric load by an optimization operation (for example, the same mode as in step 130 above) To be determined).

In Step 260, the power manager 10 associates the determined supply power distributions W _B / W _P , W _S / W _P , and W _H / W _P as actual values in association with the operation request state grasped in Step 210 above. Store in memory.

In step 270, the power manager 10 determines the supply power distributions W _B / W _P , W _S / W _P , and W _H / W _{P as determined} for each of the electric loads 20A, 20B, and 20C as necessary. An instruction is transmitted to the ECU. Note that the processing routine of steps 210 to 270 is repeated at predetermined intervals (for example, until the ignition switch is turned off).

Thus, in this embodiment, the calculated supply power distributions W _B / W _P , W _S / W _P , and W _H / W _P are stored in the memory for each operation request state of each of the electric loads 20A, 20B, and 20C. It will be accumulated within.

Here, the operation request states of the electric loads 20A, 20B, and 20C correspond to the states in which the required powers of the electric loads 20A, 20B, and 20C are respectively W _B0 , W _S0 , and W _H0 , and the required power W _B0 , There are as many combinations as possible values of W _S0 and W _H0 . For example, the ECB system 20A has three brake operation amounts, large, medium, and small, the PS system 20B has three large, medium, and small operation torques, and the seat heater 20C has a low set temperature, medium, and high. Even when the range of required power for each of the electric loads 20A, 20B, and 20C is divided with a coarse resolution, as in the three ways, there are a total of 27 operation request states for each of the electric loads 20A, 20B, and 20C. is there. Actually, there are many electric loads instead of three, and it is necessary to classify the operation request states with finer resolution. Therefore, if the above optimization calculation is performed for each operation request state, It can be easily predicted that the load will increase.

  On the other hand, according to the first embodiment, although the above-described optimization calculation is performed once for each operation request state, the operation request state is substantially the same as the operation request state previously optimized. On the other hand, the supply power distribution stored in the memory is used as it is. As a result, when substantially the same operation request state is formed, it is possible to eliminate the waste of performing the same optimization calculation performed previously, and to reduce the calculation load of the power manager 10. .

In the present embodiment, in order to classify the operation request states of the electric loads 20A, 20B, and 20C as described above, the range that can be taken by the required electric power of the electric loads 20A, 20B, and 20C is divided into appropriate sections. Are the evaluation functions F _B (W _B ), F _S (W _S ), and F _H (W _H ) of the electric loads 20A, 20B, and 20C described above, and are classifications of required power of the electric loads 20A, 20B, and 20C. May be defined for each. In this case, in step 240 described above, the power manager 10 evaluates the evaluation functions F _B (W _B ), F _S (W _S ), and F _H (W _H ) according to the operation request states of the electric loads 20A, 20B, and 20C. Are read from a predetermined memory.

  In the present embodiment, the power manager 10 preferably recalculates the supply power distribution to each electric load periodically. That is, the power manager 10 does not use the supply power distribution stored in the memory, even when an operation request state substantially the same as the operation request state that has been previously optimized and calculated is formed. The above optimization operation is performed again. Thereby, it is possible to cope with changes with time of the electric loads 20A, 20B, and 20C.

  The second embodiment is characterized in that an operation request of each electric load is predicted based on a vehicle state, and supply power distribution to each electric load is controlled based on the predicted operation request of each electric load.

  FIG. 8 is a flowchart of supply power distribution determination processing realized by the power manager 10 according to the second embodiment. Detailed description of the same processing as that described with reference to FIG. 6 is omitted.

  In step 300, the power manager 10 grasps the SOC of the battery 42.

  In step 310, the power manager 10 grasps the operation request states of the electric loads 20A, 20B, and 20C through communication with the electric loads 20A, 20B, and 20C.

  In step 320, the power manager 10 grasps the state of the vehicle. The vehicle state includes, for example, an accelerator opening sensor (accelerator position sensor) that detects an operation mode of an accelerator pedal, a shift position sensor that detects a shift operation position, and a brake stroke sensor (brake pedal force sensor) that detects an operation mode of a brake pedal. , A master cylinder pressure sensor), a steering sensor and a torque sensor for detecting an operation mode of the steering handle, a wheel speed sensor for detecting a vehicle speed, an acceleration sensor, a yaw rate sensor, and the like. Further, the state of the vehicle may be grasped in consideration of the traffic situation around the vehicle based on the own vehicle position information obtained from the navigation system, the inter-vehicle communication, the peripheral monitoring camera, and the like.

In step 330, the power manager 10 determines the electric loads 20 </ b> A, 20 </ b> A, 20 </ b> C after the current time based on the operation request states of the electric loads 20 </ b> A, 20 </ b> B, 20 </ b> C grasped in step 310 and the vehicle states grasped in step 320. The operation request states of 20B and 20C are predicted. For example, the power manager 10 predicts whether or not the operation amount of the brake pedal or the steering wheel will further increase in the next cycle, and the required power W _B0 , W _S0 of each electric load 20A, 20B, 20C in the next cycle. , W _H0 is predicted.

In step 340, the power manager 10 evaluates the estimated functions F _B (W _B ), F _S (W _S ), F according to the predicted required powers W _B0 , W _S0 , W _H0 of the electric loads 20A, 20B, 20C. _H (W _H ) is read from the predetermined memory, and the evaluation function F _P (W _P ) of the battery 42 corresponding to the SOC of the battery 42 is read from the predetermined memory. For example, when the operation of the brake assist system of the ECB system 20A is predicted based on the inter-vehicle time with the preceding vehicle, or when the brake is suddenly braked when the road surface is wet, the anti-lock brake system (ABS When the operation of the system) is predicted, or the evaluation function F _B (W _B ) corresponding to the required power W _B0 of the ECB system 20A predicted at that time is read.

In step 350, the power manager 10 uses the evaluation functions read in step 350 to perform an optimization calculation to distribute the supply power to each electric load W _B / W _P , W _S / W _P , W _H / W. _P is determined (for example, determined in the same manner as in step 130).

In step 360, the power manager 10 determines the supply power distributions W _B / W _P , W _S / W _P , and W _H / W _{P as determined} for each of the electric loads 20A, 20B, and 20C as necessary. An instruction is transmitted to the ECU. Note that the processing routine of steps 310 to 360 is repeated at predetermined intervals (for example, until the ignition switch is turned off).

  As described above, according to this embodiment, the operation demand states of the electric loads 20A, 20B, and 20C are predicted, and the supply power distribution is controlled in a feedforward manner, so that the electric loads 20A, 20B, An operating limit of 20C can be applied.

  In the present embodiment, when the total required power is predicted to greatly exceed the predetermined value α, the power supply to the low priority electric load (in this case, the seat heater 20C) is preliminarily interrupted. Thus, the power supply distribution to the remaining electric loads 20A and 20B may be optimized.

Further, in this embodiment, when the occurrence of an operation request for an electric load that consumes a large amount of power at the start of operation is predicted, the power that can be supplied from the power source is corrected to be small and the supply power distribution for each electric load is calculated. It is good as well. Specifically, when the operation start of the ECB system 20A or the PS system 20B is predicted, the power manager 10 estimates the SOC (for example, 80%) of the battery 42 grasped in the above step 300 to a small estimate (for example, 50%). (Estimate), in step 340, the evaluation function F _P (W _P ) of the battery 42 corresponding to the SOC of the battery 42 is read from a predetermined memory, and in step 350, the power supplied to each electric load is optimized. Distributions W _B / W _P , W _S / W _P , and W _H / W _P are determined. Alternatively, each of the electric functions such that the objective function Ft = F _B (W _B ) + F _S (W _S ) + F _H (W _H ) is maximized under the constraint condition of W _P = W _B + F _S + F _H <α. load 20A, 20B, supply power _W B for _20C, in the configuration for obtaining the W S, _{W H,} if the start of operation of the ECB system 20A and PS system 20B is predicted, the power manager 10 corrects small α The optimal calculation may be performed (that is, the constraint condition is corrected in a direction that becomes stricter).

  The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the present invention. Can be added.

  For example, in the above-described embodiment, the power that can be supplied from the power source is determined based on the state of only the battery 42 (that is, the SOC), but the power that can be supplied from the power source depends on the state of the battery 42 and the generator 30. Therefore, it may be determined in consideration of the operating state of the generator 30.

  In the above-described embodiment, the evaluation function is set so that the performance satisfaction is the maximum value 1 at each required power. However, the performance satisfaction is not necessarily the maximum value 1 at each required power. For example, the performance satisfaction when the supplied power becomes the required power may be a maximum value smaller than 1.

  In the above-described embodiment, the evaluation functions of the electric loads 20A, 20B, and 20C are stored in the memory of the power manager 10, but the evaluation functions of all the electric loads are stored in the memory of the power manager 10. It is not always necessary to keep it. That is, the respective evaluation functions are stored in the memories in the ECUs of the electric loads 20A, 20B, and 20C, and the performance satisfaction with respect to the current supply power is determined from the electric loads 20A, 20B, and 20C. 10 may be notified respectively.

It is a figure which shows the basic system structure which concerns on the electric power management apparatus for vehicles of this invention. It is a figure which shows an example of the evaluation function of ECB system 20A. It is a figure which shows an example of the evaluation function of PS system 20B. It is a figure which shows an example of the evaluation function of 20 C of seat heaters. 4 is a diagram illustrating an example of an evaluation function F _P (W _P ) of a battery 42. FIG. It is a flowchart of the determination process of the supply electric power distribution with respect to each electric load by the electric power manager. It is a flowchart of the supply power distribution determination process implement | achieved by the power manager 10 by Example 1. FIG. It is a flowchart of the supply power distribution determination process implement | achieved by the power manager 10 by Example 2. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Electric power manager 20A, 20B, 20C Electric load 30 Generator 42 Battery

Claims (7)

In the vehicle power management device that controls the distribution of power supplied to a plurality of electric loads,
Deriving the performance satisfaction characteristics of the electrical load relative to the supplied power for each electrical load,
A power management apparatus for a vehicle, wherein a power supply distribution for each electric load is calculated based on a power supply state, an operation request state of each electric load, and a performance satisfaction characteristic of each electric load. Performance satisfaction characteristics of each electrical load are expressed as performance satisfaction as a common index among multiple electrical loads.
The vehicle according to claim 1, wherein power that can be supplied from a power supply is used as a constraint condition, and a supply power distribution for each electric load is optimized so that a total value of the performance satisfaction levels in each electric load is maximized. Power management equipment.   For each operation request state of each electric load, the calculated supply power distribution to each electric load is stored as an actual value, and the supply power distribution to each electric load is determined according to the stored actual power distribution value. The vehicle power management apparatus according to claim 1 or 2, wherein the power management apparatus is determined.   The vehicular power management apparatus according to claim 3, wherein the recalculated supply power distribution is periodically used in place of the stored actual power distribution value.   The vehicle power supply according to claim 1 or 2, wherein an operation request for each electric load is predicted based on the vehicle state, and a distribution of power supplied to each electric load is calculated based on the predicted operation request for each electric load. Power management device.   When an operation request for a predetermined electric load that consumes a large amount of power at the start of operation is predicted, the power that can be supplied from the power supply is corrected so that the power that can be supplied decreases, and the supply to each electric load is performed. The vehicle power management apparatus according to claim 5, wherein the power distribution is calculated. Each electrical load has a power supply priority,
The power supply distribution to each of the remaining electric loads is calculated under a condition in which the power supply to the low priority electric loads is interrupted in advance when the power supply state falls below a predetermined standard. 5. The vehicle power management device according to 5.

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