JP5709722B2 - Vehicle power supply - Google Patents

Description

  The present invention relates to a vehicle power supply apparatus that efficiently performs power generation and actively performs regenerative power generation during vehicle deceleration.

  Among conventional vehicle power supply devices, for a vehicle power supply device that efficiently generates power, for example, as disclosed in Patent Document 1, the generator generates power at an operating point where power generation efficiency is maximum. A device having voltage conversion means for controlling and converting the magnitude of the output voltage of the generator into a predetermined voltage value is disclosed.

  According to this conventional apparatus, since the output terminal voltage of the generator is made variable, the maximum output power is increased and the power is generated with the output terminal voltage at which the efficiency is optimum, so that the power generation efficiency is also improved. Moreover, although the voltage suitable for an electric load or a battery and the generator output terminal voltage at which the power generation efficiency is maximized are generally different, a configuration satisfying both of them can be realized.

JP 2001-103796 A

  In the case of the above-mentioned conventional device, since the output terminal voltage of the generator is made variable, it is certainly compared with the case where the output voltage of the generator is regulated to a constant value by directly connecting the generator and the battery. Thus, it is possible to generate more power. However, if sufficient power generation torque is supplied during regenerative power generation control using deceleration energy of the vehicle during vehicle deceleration, power generation is not performed using fuel, so even if efficiency is somewhat low, more It is more advantageous to generate power. In this case, the output terminal voltage of the generator needs to be a value that is not an operating point at which the power generation efficiency is maximum but an operating point at which the generated power is maximum.

  On the other hand, when the generated power is increased, the driving force and torque required by the generator are also increased. In this case, it is sufficient that power generation is always performed stably. For example, if power generation must be stopped due to the state of charge of the battery during high power generation such as during regenerative power generation, the driving torque of the generator is reduced. There is a concern that drivability will deteriorate due to a sudden drop in shock and a change (decrease) in the feeling of deceleration. In order to prevent this, it is conceivable that power generation is performed in cooperation with the hydraulic brake, but there is a concern that the brake mechanism becomes complicated and costs increase.

  The present invention has been made to solve the above-described problems in the conventional apparatus, and can appropriately switch between high-efficiency power generation and high-output power generation, and does not complicate the brake mechanism. An object of the present invention is to provide a vehicular power supply device that can prevent the deterioration of performance.

A power supply device for a vehicle according to a first aspect of the present invention is a generator that generates electric power using the driving energy of the vehicle or the energy of the internal combustion engine as a driving source, stores the electric power generated by the generator, and supplies the electric load to the electric load of the vehicle And a power supply device for a vehicle including a voltage converter having a first end connected to a generator and a second end connected to an electrical load.
Torque that can be used for power generation of the generator, that is, power generation allowable torque setting means for setting power generation allowable torque that is a torque that the generator uses for power generation, which is required so as not to affect the drivability of the vehicle even if power generation is stopped With
Calculate the power that can be generated, which is the maximum power that the generator can generate when the generator allowable torque is used at the generator rotation speed, and the maximum power that can be generated by the generator at the rotation speed of the generator. When the power that can be generated is greater than or equal to the maximum generated power, the generator operates with the maximum generated power. When the power that can be generated is less than the maximum generated power, the generator operates with the power that can be generated at the maximum power generation efficiency. The generator and the voltage converter are controlled.

A power supply device for a vehicle according to a second aspect of the invention is a generator that generates electric power using the driving energy of the vehicle or the energy of the internal combustion engine as a driving source, stores the electric power generated by the generator, and supplies the electric load to the electric load of the vehicle Power storage device, a voltage converter having a first end connected to a generator and a second end connected to an electric load, a request to the second end of the voltage converter based on a charge state of the power storage device and / or a running state of the vehicle Output value or output voltage required value and required output power calculating means for calculating required output power corresponding to the required value, target generated power for calculating the target generated power of the generator based on the required output power Calculation means, target power generation voltage setting means for setting the target power generation voltage of the generator based on the target power generation, and generator control for controlling the power generator so that the power generation voltage of the power generator becomes the target power generation voltage. Means, and a vehicle power supply device including a voltage converter control means by the output current or the output voltage of the second end of the voltage converter controls the voltage converter to be a required value,
Torque that can be used for power generation of the generator, that is, power generation allowable torque setting means for setting power generation allowable torque that is a torque that the generator uses for power generation, which is required so as not to affect the drivability of the vehicle even if power generation is stopped With
The target generated power calculation means is the maximum power that can be generated by the generator at the rotation speed of the generator and the maximum power that can be generated by the generator at the rotation speed of the generator. Calculate the generated power and the maximum power generated voltage that is the generated voltage when it becomes the maximum generated power, calculate the minimum power among the required output power, the power that can be generated and the maximum generated power as the target generated power,
The target generated voltage setting means sets the maximum power generated voltage as the target generated voltage when the target generated power is equal to the maximum generated power, and sets the rotation speed of the generator and the target generated power when the target generated power is smaller than the maximum generated power. Based on the electric power, a maximum efficiency power generation voltage that is a power generation voltage that maximizes the power generation efficiency of the generator is calculated, and the maximum efficiency power generation voltage is set as a target power generation voltage.

As described above, the power supply device for a vehicle according to the present invention is a torque that can be used for power generation by the generator, that is, the generator is used for power generation that is required not to affect the drivability of the vehicle even if the power generation is stopped. A power generation allowable torque setting means for setting a power generation allowable torque that is a torque to be generated;
In the first aspect of the invention, the maximum power that can be generated by the generator at the rotational speed of the generator and the maximum power that can be generated by the generator at the rotational speed of the generator. The generated power is calculated so that the generator operates at the maximum generated power when the power that can be generated is greater than or equal to the maximum generated power, and the generator is at the maximum power generation efficiency when the power that can be generated is less than the maximum generated power. Control generators and voltage converters to operate on power that can be generated,
In the second aspect of the invention, the maximum power that can be generated by the generator at the rotational speed of the generator and the maximum power that can be generated by the generator at the rotational speed of the generator. Calculate the maximum power generation voltage and the maximum power generation voltage, which is the power generation voltage when the maximum power generation power is reached, and calculate the minimum power among the required output power, the power that can be generated, and the maximum power generation power as the target power generation power. When the generated power is equal to the maximum generated power, the maximum power generated voltage is set as the target generated voltage.When the target generated power is smaller than the maximum generated power, the generator power is generated based on the rotational speed of the generator and the target generated power. The maximum efficiency power generation voltage, which is the power generation voltage that maximizes the efficiency, is calculated and the maximum efficiency power generation voltage is set as the target power generation voltage. If a large electric power is required to power the largest power, power can be generated at the maximum efficiency in the case of other.
In addition, by appropriately setting the power generation allowable torque at the time of regenerative power generation using the driving energy of the vehicle and the power running power generation using the energy of the internal combustion engine as a drive source, the power generation torque (power generation allowable torque at the time of regenerative power generation) is set. ) Can be sufficiently generated, more power can be generated, and when powering power generation using fuel is performed, power generation can be performed efficiently. On the other hand, when the torque that can be used for power generation (power generation allowable torque) is not sufficiently obtained even during regenerative power generation, high-efficiency power generation is performed, so that more generated power can be obtained with limited power generation torque. In short, it is possible to provide a vehicular power supply device that can appropriately switch between high-efficiency power generation and high-output power generation and can prevent deterioration in drivability due to a change in power generation torque without complicating the brake mechanism. .

It is a block diagram which shows the vehicle power supply device in Embodiment 1 of this invention. It is a figure which shows the internal structure of the control unit 6 of FIG. It is a flowchart which shows the process performed in the fixed period in the vehicle power supply device of Embodiment 1 of this invention. It is a flowchart which shows the processing content in target generation electric power calculation process S103 of FIG. It is a characteristic view which shows an example of the electric power possible electric power characteristic of the generator 1 in the vehicle power supply device of Embodiment 1 of this invention. It is a characteristic view which shows an example of the maximum generated electric power characteristic of the generator 1 in the vehicle power supply device of Embodiment 1 of this invention. It is a flowchart which shows the processing content in the target electric power generation voltage setting process S104 of FIG. It is a characteristic view which shows an example of the electric power generation torque characteristic of the generator 1 in the vehicle power supply device of Embodiment 1 of this invention. It is a block diagram which shows the vehicle power supply device in Embodiment 2 of this invention. It is a figure which shows the internal structure of 6 A of control units of FIG. It is a flowchart which shows the process performed in the fixed period in the vehicle power supply device of Embodiment 2 of this invention. It is a block diagram which shows the vehicle power supply device in Embodiment 3 of this invention. It is a circuit diagram which shows an example of an internal structure of the voltage converter 2 of FIG.

Embodiment 1 FIG.
Hereinafter, a vehicle power supply device according to an embodiment of the present invention will be described with reference to the drawings. 1 is a block diagram showing a vehicle power supply apparatus according to Embodiment 1 of the present invention.

  In FIG. 1, a generator 1 generates electric power by using driving energy of a vehicle or energy of an internal combustion engine (not shown) as a drive source, and is usually belt-connected to the internal combustion engine. As another configuration, for example, it may be sandwiched and connected between an internal combustion engine and a transmission (not shown), and can be driven with a larger power generation torque than the belt connection. Further, if the internal combustion engine is provided with a clutch, the internal combustion engine can be disconnected by operating the clutch during vehicle deceleration, that is, during regenerative power generation using the vehicle running energy as a drive source. The resistance can also be used for power generation, and the regenerative power is larger than that, which is advantageous.

  The configuration of the generator 1 may be the same as an alternator used in a general vehicle, and the generated power can be adjusted by controlling the field current flowing through the rotor. However, in order to increase the power generation voltage as described later, it is necessary to have a configuration capable of generating power at a higher voltage than the conventional one.

  The voltage converter 2 has a first end serving as an input connected to the generator 1 and a second end serving as an output connected to a load feeding bus 5, and the voltage between the first end and the ground end and the second end to the ground end Voltage conversion is performed between The load power supply bus 5 is connected to a lead battery 3 as a power storage device and an in-vehicle electric load 4 as an electric load, and the generated power of the generator 1 is supplied to these via the voltage converter 2 and the load power supply bus 5. The

  As a specific configuration of the voltage converter 2, a known chopper circuit using a switching element such as a MOSFET can be employed. The voltage converter 2 is turned ON / OFF by the voltage converter control means 2a built in the voltage converter 2 so that the current, voltage, and power output to the second terminal, which is the output side terminal. And the switching element is operated so that the output current or the output voltage at the second end becomes the required value instructed from the required output power calculating means 60 of the control unit 6 described later.

  Further, regarding the voltage conversion of the voltage converter 2, the lead battery 3 used in a general vehicle has an open circuit voltage of about 12V and a charging voltage of about 14V, so if the power generation voltage of the generator 1 is set higher than 14V. The voltage converter 2 may be configured to always perform the voltage conversion from the first end to the second end in the step-down direction. By selecting such a voltage range, the voltage conversion in the step-down and step-up directions can be performed. It is possible to make the configuration simpler than that required. As for the maximum voltage of the generator 1, it is difficult to increase the voltage unnecessarily due to restrictions on parts and safety in preventing electric shocks. For example, 28 V is appropriate considering the characteristics of the generator 1. It is.

  As shown in FIG. 2, the control unit 6 includes an arithmetic unit (hereinafter referred to as a CPU) such as a microcomputer and a memory (not shown). Power generation allowable torque setting means 61, target generated power calculation means 62, target generated voltage setting means 63, and generator control means 64 are provided. The voltage converter control means 2a may be provided in the control unit 6 instead of being built in the voltage converter 2. In addition, the control unit 6 is connected to sensors, actuators, and the like provided in an internal combustion engine or the like, although the individual descriptions are omitted.

  In the control unit 6, the generator 1 and the actuator are controlled, and the voltage converter control means 2 a of the voltage converter 2 is instructed of a required value that is an output current or an output voltage. In addition, detection of the vehicle running state by the connected accelerator sensor 10, brake switch 11, and vehicle speed sensor (not shown), and detection of the charge state of the lead battery 3 by the battery sensor 12 are performed by known methods.

  For example, for detection of the vehicle running state, the accelerator sensor 10 may detect the amount of accelerator operation by the driver and output a signal corresponding to the detected value. The presence / absence of an accelerator operation can be detected from this signal. If the accelerator is depressed, it can be determined that there is an acceleration request. On the other hand, if there is no accelerator operation and the operation amount is 0 (zero), it is determined that the vehicle intends to decelerate. When the condition is satisfied, the fuel supply to the internal combustion engine is stopped. The brake switch 11 detects a brake operation and outputs a signal indicating whether or not the brake is depressed. From these detection results and the vehicle speed, it can be determined whether or not the vehicle is in a deceleration state.

  Moreover, about the detection of the charge state of the lead battery 3, the voltage and electric current of the lead battery 3 are detected with the battery sensor 12 provided in the lead battery 3, and the charge rate estimation and charge of the lead battery 3 are performed based on these values. Judgment is necessary.

  Furthermore, a rotation sensor (not shown) provided in the internal combustion engine is also connected to the control unit 6 so that the rotational speed of the internal combustion engine can be detected by a known means. From the obtained rotation speed, the rotation speed of the generator 1 can be calculated from the pulley ratio in the belt connection, and the rotation sensor is not required to be installed in the generator 1. In this regard, when a motor generator or the like is used as a generator, it may be used if the motor generator is provided with a rotation sensor.

  Next, the operation of the vehicle power supply device according to Embodiment 1 of the present invention will be described. FIG. 3 is a flowchart showing processing executed at a constant cycle (for example, 0.01 seconds) in the vehicle power supply device according to Embodiment 1 of the present invention.

  In FIG. 3, first, in step S101, the required output power calculation means 60 performs a required output power calculation process, and the second voltage converter 2 of the voltage converter 2 is based on the charge state of the lead battery 3 or the running state of the vehicle. A required value which is an output current or output voltage required at the end and a required output power which is output power related to the required value are calculated. Since the calculation method can be considered that the voltage converter 2 functions in the same manner as a general vehicle alternator when viewed from the load power supply bus 5, the conventional power generation control method can be used.

  For example, it is preferable to switch the generated voltage according to the state of charge of the lead battery 3 or the traveling state of the vehicle. In this case, the set power generation voltage may be instructed to the voltage converter control means 2a built in the voltage converter 2 to directly control the voltage at the second end of the voltage converter 2, or the set power generation voltage The output current may be obtained in advance by feedback control so that the obtained current value is instructed to the voltage converter control means 2a, and the current value may be controlled by the voltage converter 2. The required output power can be obtained by detecting or estimating the current and multiplying it with the required voltage when the voltage is the required value. What is necessary is just to obtain | require by detecting and multiplying with the required value of electric current.

  Further, based on the traveling state of the vehicle, during traveling other than deceleration, the generated voltage is reduced according to the charging rate of the lead battery 3 to suppress the generated power, and the charging rate of the lead battery 3 during regenerative power generation during deceleration. It is better to increase the generated voltage by increasing the generated voltage so as to recover the power. As a result, fuel used for power generation can be reduced and fuel consumption can be improved.

Next, in step S102, a power generation allowable torque setting process is performed by the power generation allowable torque setting means 61, and a power generation allowable torque that is a torque that can be used for power generation of the generator 1 is set.
As described above in the section of the problem to be solved by the invention, especially during regenerative power generation, when generating a large amount of torque and generating power, depending on the state of charge of the power storage device, for example, power generation is performed to avoid full charge. If a sudden stop occurs, a shock due to a sudden change in the deceleration of the vehicle occurs and drivability deteriorates.
Therefore, in order to prevent such a problem, in the present invention, the torque used for power generation of the generator is controlled to be equal to or less than a preset value. It is defined as “torque that can be used for“ power generation allowable torque ”.
Therefore, as a method for setting the power generation allowable torque, it is only necessary to determine that the drive torque difference of the generator 1 depending on whether or not power is generated does not affect drivability.
Since drivability is affected by changes in the driving force of the vehicle, it is only necessary to set the power generation allowable torque so that the power generation power of the generator 1 is constant. The higher the rotational speed of the generator 1, the higher the power generation. It is preferable to set the allowable torque to be small.

During vehicle deceleration, in which the generator 1 generates power using the travel energy of the vehicle as a driving source, the influence on drivability is large. Therefore, a change in vehicle deceleration that occurs when power generation is stopped during vehicle deceleration, in other words, The power generation allowable torque may be set so that the change in the vehicle deceleration between the case where the generator 1 generates power with the power generation allowable torque and the case where power generation is not performed is within a predetermined value.
When the generator 1 generates power using the energy of the internal combustion engine as a drive source during acceleration or the like, the output adjustment of the internal combustion engine can be performed relatively easily, and accordingly, according to the change in the drive torque accompanying the stop of the generator 1 What is necessary is just to adjust the output of an internal combustion engine. On the other hand, at the time of deceleration, it is necessary to adjust the braking force of the brake, so the brake system must cope with the change. However, the brake system that does not have such a function has a complicated mechanism and costs. There is a concern that causes an increase. Therefore, it is possible to prevent deterioration in drivability by setting the power generation allowable torque so that the change in the deceleration of the vehicle is within a predetermined value instead of adjusting the braking force of the brake.

  The deceleration depends on the running resistance of the vehicle, and considering that the running resistance is higher at higher vehicle speeds, the power generation allowable torque increases as the vehicle speed increases because the influence of the power generation allowable torque on the deceleration is less at higher vehicle speeds. It is good to set so that Since the vehicle speed and the running resistance have the same relationship even when the vehicle is accelerated, the allowable power generation torque may be set to increase as the vehicle speed increases even when the vehicle is accelerated.

  In step S103, the target generated power calculation process is performed by the target generated power calculation means 62 to calculate the target generated power. In step S104, the target generated voltage setting process is performed by the target generated voltage setting means 63, and the target generated voltage is calculated. Set. Details of these processes will be described later with reference to FIGS. 4 and 7.

  Finally, in step S105, generator control processing is performed by the generator control means 64 to control the generator 1 so that the set target generated voltage is reached, and the processing shown in FIG. As a control method, a known method may be used. From the characteristics of the generator 1, feedback control may be performed so that the generated power increases when the generated voltage decreases and the generated power decreases when the generated voltage increases. Control can be performed by controlling the field current.

  Next, the target generated power calculation process performed in the above-described step S103 will be described. FIG. 4 is a flowchart showing a target generated power calculation process in the vehicle power supply apparatus according to Embodiment 1 of the present invention.

  In FIG. 4, first, in step S201, as described above, the rotational speed of the generator 1 is calculated in consideration of the pulley speed in the detected rotational speed of the internal combustion engine.

  Next, in step S202, the power that can be generated is calculated based on the power generation allowable torque set in step S102 (FIG. 3). The power generation characteristics of the generator 1 measured in advance are stored in the control unit 6, and the maximum power that can be generated by the generator 1 using the power generation allowable torque at the rotation speed of the generator 1 calculated in step S201 is generated power. Asking.

  In step S203, the maximum power that can be generated by the generator 1 is calculated as the maximum generated power based on the rotational speed of the generator 1, and in step S204, the maximum power generated voltage that is the generated voltage at that time is calculated. Also for these values, the power generation characteristics of the generator 1 measured in advance may be stored in the control unit 6 and obtained according to the rotational speed of the generator 1.

  Here, for reference, as an example of the power generation characteristics of the generator 1, FIG. 5 shows a power generation capability characteristic and FIG. 6 shows a maximum power generation characteristic.

  The electric power generation characteristic shown in FIG. 5 shows the change of the generated electric power with respect to the generated voltage at the time of a certain generation torque. In general alternators, the maximum voltage that can be generated is determined according to the rotational speed, and the maximum generated voltage increases as the rotational speed increases. Further, if the rotational speed increases while the power generation torque is constant, the power received by the generator 1 increases. Therefore, if the power generation allowable torque is the same, the power that can be generated increases according to the rotational speed. The generated voltage will also change.

  The maximum generated power characteristic shown in FIG. 6 shows the maximum generated power from the generated power for the rotation speed for each generated voltage in the upper stage, and the maximum generated power voltage that is the generated voltage at the lower stage. . As described above, the maximum voltage that can be generated is determined according to the rotation speed, and the generated power tends to increase as the generation voltage increases.From these trends, the maximum voltage increases as the rotation speed increases. The generated power will also increase and the maximum power generation voltage will also increase.

  Finally, in steps S205 to S207, the minimum value is selected from the required output power, the power that can be generated, and the maximum generated power. In steps S208 to S210, the target generated power is substituted and the processing in FIG. .

  Specifically, in step S205, power that can be generated> maximum generated power? If Yes, the process proceeds to step S206, and if No, the process proceeds to step S207. In step S206, required output power> maximum generated power? If YES in step S208, the flow advances to step S208 to substitute the maximum generated power into the target generated power, and the process ends. If No in step S206, the process proceeds to step S209, the requested output power is substituted into the target generated power, and the process is terminated.

  In step S207, required output power> power that can be generated? If YES in step S210, the flow advances to step S210 to substitute the power that can be generated into the target generated power, and the process ends. If No in step S207, the process proceeds to step S209, where the requested output power is substituted for the target generated power, and the process ends.

  Next, the target generated voltage setting process performed in step S104 in FIG. 3 will be described. FIG. 7 is a flowchart showing a target generated voltage setting process in the vehicle power supply device according to the first embodiment of the present invention.

  In FIG. 7, it is determined in step S301 whether the target generated power is equal to the maximum generated power. If the determination is Yes and the target generated power and the maximum generated power are equal, the process proceeds to step S302, the maximum generated power voltage is set as the target generated voltage, and the process of FIG.

On the other hand, if the determination in step S301 is No and the target generated power is not equal to the maximum generated power, the target generated power is greater than the maximum generated power from the contents of steps S205 to S207 of the target generated power calculation process (FIG. 4). Therefore, the process proceeds to step S303 to calculate the maximum efficiency generated voltage at which the generator 1 has the maximum power generation efficiency at the rotation speed of the generator 1 and the target generated power. In step S304, the maximum efficiency generated voltage is calculated. The efficiency power generation voltage is set to the target power generation voltage, and the process of FIG.
The target generated power is smaller than the maximum generated power when the required output power is the target generated power (step S209) and when the power that can be generated is the target generated power (step S210). Corresponds.

  When the target generated power is equal to the maximum generated power, the generator 1 needs to increase the generated power as much as possible. Therefore, the generated power should be given priority over the power generation efficiency, and the maximum generated power voltage should be set as the target generated voltage. You just have to set it. On the other hand, when the target generated power is smaller than the maximum generated power, the power generation capacity of the generator 1 has a margin. Therefore, the maximum efficiency generated voltage should be set as the target generated voltage with priority on the power generation efficiency. become.

  Here, as an example of the power generation characteristics of the generator 1, for reference, a power generation torque characteristic that is a characteristic of power generation torque with respect to a certain generated power and a generated voltage at the rotation speed is shown in FIG. The state in which the power generation efficiency is the highest is a state in which the power generation torque used when generating the same power is the minimum, so the power generation voltage at the point shown in FIG. 8 is the maximum power generation voltage. Incidentally, when the target generated power is equal to the power that can be generated, the generated voltage when the power that can be generated shown in FIG. 5 is the maximum efficiency generated voltage. This is because if the power generation torque to be used is the same, the power generation efficiency is the best when the generated power is maximum. In this case, when calculating the power that can be generated, the generated voltage at that time may also be held.

As described above, the vehicle power supply device according to Embodiment 1 of the present invention includes the predetermined power generation allowable torque setting unit 61 and the target generated power calculation unit 62 to perform the target generated power calculation process. The target power generation power is calculated by calculating the minimum power among the required output power, the power that can be generated, and the maximum power generation as the target power generation power, and further including the target power generation voltage setting means 63 to perform the target power generation voltage setting processing. Is equal to the maximum generated power, the maximum power generated voltage is set as the target generated voltage, and when the target generated power is smaller than the maximum generated power, the generator 1 generates power based on the rotational speed of the generator 1 and the target generated power. The maximum efficiency power generation voltage, which is the power generation voltage that maximizes the efficiency, is calculated and the maximum efficiency power generation voltage is set as the target power generation voltage. There when a large power is required to power the largest power, power can be generated at the maximum efficiency in the case of other.
In addition, by appropriately setting the power generation allowable torque at the time of regenerative power generation using the driving energy of the vehicle and the power running power generation using the energy of the internal combustion engine as a drive source, the power generation torque (power generation allowable torque at the time of regenerative power generation) is set. ) Can be sufficiently generated, more power can be generated, and when powering power generation using fuel is performed, power generation can be performed efficiently. On the other hand, when the torque that can be used for power generation (power generation allowable torque) is not sufficiently obtained even during regenerative power generation, high-efficiency power generation is performed, so that more generated power can be obtained with limited power generation torque. In short, it is possible to provide a vehicular power supply device that can appropriately switch between high-efficiency power generation and high-output power generation and can prevent deterioration in drivability due to a change in power generation torque without complicating the brake mechanism. .

In this type of vehicle power supply device, it is generally assumed that the required value and the required output power, which are the output current or output voltage of voltage converter 2, are required. Although the present invention has been described as including the calculation means 60, the present invention includes a power generation allowable torque setting means 61 that sets a power generation allowable torque that is a torque that can be used for power generation of the generator 1, as understood in the above description. The main feature is that it is possible to appropriately switch between high-efficiency power generation and high-power power generation of the generator 1 under the limit of the power generation allowable torque, thereby generating power without complicating the brake mechanism. It is possible to prevent deterioration of drivability due to torque change.
Therefore, in particular, the required output power calculation means is not provided, and in this case, when the generator allowable torque is used at the rotation speed of the generator, the power that can be generated is the maximum power that the generator can generate, and the rotation of the generator. The maximum generated power that can be generated by the generator at the speed is calculated, and when the power that can be generated is greater than or equal to the maximum generated power, the generator is operated at the maximum generated power. If it is less than the above, the generator and the voltage converter are controlled so that the generator operates with the power that can be generated at the maximum power generation efficiency, and the same effect as described above can be obtained.

Embodiment 2. FIG.
FIG. 9 is a configuration diagram showing a vehicle power supply device according to Embodiment 2 of the present invention. Here, a voltage converter and a power storage device are further connected between the generator 1 and the voltage converter 2 with respect to the first embodiment. That is, as shown in FIG. 9, a second voltage converter 7 is connected between the generator 1 and the voltage converter 2, with the first end connected to the generator 1 and the second end connected to the voltage converter 2. Then, a lithium ion battery 8 that is a second power storage device is connected to the second end of the second voltage converter 7 so as to be connected in parallel with the lead battery 3 via the voltage converter 2.

  In FIG. 9, the generator 1, the lead battery 3 connected to the load power supply bus 5, and the in-vehicle electric load 4 may be the same as those in the first embodiment. As shown in FIG. 10, the control unit 6 </ b> A includes a power generation execution determination unit 65, a charging power calculation unit 66, and a second required output power calculation unit 67 in addition to those similar to those in the first embodiment. . In addition, the battery sensor 13 is connected to the control unit 6A in order to detect the state of charge of the lithium ion battery 8.

  Regarding the voltage conversion of the voltage converter 2 and the second voltage converter 7, if the maximum voltage of the generator 1 is 28V, the second voltage converter is 28V if the minimum voltage of the lithium ion battery 8 is 28V or higher. 7 is only required to step up the voltage in the direction from the first end to the second end. The voltage converter 2 steps down the voltage in the direction from the first end to the second end, and the reverse direction is from the second end to the second end. It is sufficient that the voltage can only be boosted in the direction of one end. By selecting such a voltage level, these voltage converters can have a simpler configuration.

  In this case, since the use voltage range of the general lithium ion battery 8 is 3 to 4.2V, it may be 10 series, and the use voltage range of the lithium ion battery 8 is 30 to 42V.

  The configuration of the voltage converter 2 may be the same as that of the first embodiment, but is controlled by the voltage converter control means 2a so that power can be output in both directions. The output current or output voltage of the first end or the second end instructed as the output side is controlled so that the required value of the current or voltage instructed from the control unit 6A including the output direction is obtained.

  The configuration of the second voltage converter 7 may be the same as that of the voltage converter 2 of the first embodiment, and may be connected in the reverse direction so that the voltage conversion is in the boosting direction. The second voltage converter control means 7a is built in the second voltage converter 7, and as will be described later, the output current or the output voltage is the second request for the current or voltage instructed from the control unit 6A. Operate the switching element to a value.

  Next, the operation of the vehicle power supply device according to Embodiment 2 of the present invention will be described. FIG. 11 is a flowchart showing processing executed in a constant cycle (for example, 0.01 seconds) in the vehicle power supply device according to Embodiment 2 of the present invention.

In FIG. 11, first, in step S <b> 401, the power generation execution determination process is performed by the power generation execution determination unit 65 to determine whether or not to generate power. As the determination contents, for example, it is determined that power generation is performed when the vehicle is in a decelerating state or the charging rate of the lithium ion battery 8 is decreased, and it is determined that power generation is not performed otherwise.
As will be described later, when power generation is prohibited and charging of the lithium ion battery 8 is not performed, electric power is supplied from the lithium ion battery 8 to the load power supply bus 5 via the voltage converter 2. In this way, by actively performing power generation during regenerative power generation during deceleration and prohibiting power generation as much as possible in other states, it is possible to reduce fuel used for power generation and improve fuel efficiency.

  In step S402, if it is determined that the charging power calculation unit 66 performs the charging power calculation process and the power generation is not performed, it is necessary to charge the lithium ion battery 8 from the lead battery 3 via the voltage converter 2. And charging power is calculated when charging is necessary. If it is normal, the lithium ion battery 8 is charged from the generator 1, but if this state continues without being charged due to power generation stop or the like, and the voltage of the lithium ion battery 8 falls below the lower limit of use, If the battery is left in that state, it will deteriorate rapidly, so it will be charged from the lead battery 3.

  In particular, although not provided in the present embodiment, it is effective when there is an electric load driven by the power of the lithium ion battery 8 and the power for driving it is insufficient. Further, when a capacitor is used instead of the lithium ion battery as the power storage device, the capacitor has a relatively small capacity, and therefore it is preferable to charge from the lead battery 3 when the charging rate is lowered.

  In step S403, the required output power calculation process is performed by the previous required output power calculation means 60, and the output value or output voltage required for the voltage converter 2 is the required value and the output power related to the required value. Calculate the required output power. Since the load power supply bus 5 and the like are connected to the second end of the voltage converter 2 as in the first embodiment, the calculation method is performed at the second end on the output side except when the lithium ion battery 8 is charged. It may be the same as the required output power calculation process (step S101) in the first mode.

  In addition, when it is determined that power generation is not performed and the charging power is calculated based on the determination that the lithium ion battery 8 needs to be charged, the charging power calculation processing is performed with the first end of the voltage converter 2 as the output side. The required value of output current or output voltage may be calculated based on the calculated charging power.

  In step S404, the second required output power calculation unit 67 performs the second required output power calculation process, and the second required value that is the output current or output voltage required at the second end of the second voltage converter 7 is obtained. And the 2nd request | requirement output power which is the output power which concerns on the said request value is calculated. Since the lithium ion battery 8 and the voltage converter 2 are connected to the second end of the second voltage converter 7, the calculation method basically corresponds to the charging method of the lithium ion battery 8. What is necessary is just to calculate considering the required output power in the obtained value.

That is, the calculation of the second required output power is performed by calculating the second required value and the second required output power based on the state of charge of the lithium ion battery 8 or the running state of the vehicle and the required output power.
It should be noted that a general method of charging the lithium ion battery 8 is to charge at the rated current until the maximum usable voltage is reached, and to maintain and charge the voltage when the maximum usable voltage is reached. Is obtained. Needless to say, if the power storage devices are different, the calculation method is accordingly adapted.

  In particular, charging is performed with high power so that the rated condition is satisfied only when the vehicle is decelerated, and charging is performed with low power that can maintain the charging rate in other cases. If it does in this way, the free capacity of lithium ion battery 8 can be secured appropriately, and the electric power recovery at the time of regenerative power generation can be performed more effectively.

  When power generation is not performed, the value calculated in the second required output power calculation process is not used, so the process may not be performed. In this case, as described above, the required output power for the voltage converter 2 is supplied from the lithium ion battery 8.

  The power generation allowable torque setting processing by the power generation allowable torque setting means 61, the target power generation calculation processing by the target power generation calculation means 62, and the target power generation voltage setting processing by the target power generation voltage setting means 63 from step S405 to step S407 are the target power generation. Except for using the second required output power instead of the required output power in the power calculation process, it may be equivalent to steps S102 to S104 of the first embodiment. In addition, since the value calculated by these is not used when it is determined not to carry out power generation, the process may not be performed in this case.

  Finally, in step S408, the generator control means 64 performs the generator control process, and when it is determined that power generation is to be performed, the generator 1 is controlled to achieve the set target generation voltage, and the power generation is performed. If it is determined not to be performed, control is performed so that the power generated by the generator 1 becomes 0 (zero), and the process shown in FIG. 11 is terminated. Control during power generation may be the same as in the first embodiment.

  As described above, in the vehicle power supply device according to Embodiment 2 of the present invention, the second voltage converter 7 and the lithium ion battery 8 connected between the generator 1 and the voltage converter 2, the second requirement. When it is determined that the power generation is performed by including the output power calculation unit 67 and the second voltage converter control unit 7a and the power generation execution determination unit 65, the second required output power calculation unit 67 is a lithium ion Based on the charged state of the battery 8 and / or the running state of the vehicle and the required output power, the output current or output voltage required at the second end of the second voltage converter 7 is used as the second required value, and the second required value. The required output power is calculated as the second required output power, and the target generated power calculation means 62 calculates the target generated power based on the second required output power instead of the required output power, and performs the power generation. When it is determined that the generator 1 does not, the generator control unit 64 controls the generator 1 so that the generated power of the generator 1 becomes 0, and the voltage converter control unit 2a is connected to the second end of the voltage converter 2. Since power is supplied from the lithium ion battery 8 to the lead battery 3 and the vehicle-mounted electric load 4 through the voltage converter 2 by controlling the voltage converter 2 so that the output current or the output voltage becomes the required value. Since power can be supplied to the voltage converter 2 without performing power generation, and power can be stored in the lithium ion battery 8 when power generation is performed, power generation can be actively performed during regenerative power generation during deceleration. In other states, by prohibiting power generation as much as possible, fuel used for power generation can be reduced and fuel efficiency can be improved.

  In addition, when it is determined that the power generation is not performed and the charging power is calculated by the charging power calculation unit 66, the required output power calculation unit 60 determines whether the voltage converter 2 of the voltage converter 2 is based on the charging power. An output current or output voltage required at one end is calculated as a required value, and the voltage converter control means 2a causes the voltage converter 2 so that the output current or output voltage at the first end of the voltage converter 2 becomes the required value. Therefore, the lithium ion battery 8 can be smoothly charged by supplying electric power from the lead battery 3 via the voltage converter 2.

Embodiment 3 FIG.
FIG. 12 is a configuration diagram showing a vehicle power supply device according to Embodiment 3 of the present invention. In contrast to the first embodiment, the second voltage converter 7 is connected in series between the generator 1 and the voltage converter 2 in the second embodiment, but here, the second voltage converter 7 is connected in parallel to the voltage converter 2. The second voltage converter 7 is connected. As shown in FIG. 12, a second voltage converter 7 is connected in parallel with the voltage converter 2, the generator 1 is connected to the first end of the second voltage converter 7, and lithium that is the second power storage device is connected to the second end. An ion battery 8 is connected.

  In FIG. 12, each component may be the same as that in the second embodiment, except that the second voltage converter 7 can also be configured to output power in both directions. If the voltage conversion of the voltage converter 2 and the second voltage converter 7 is also in the same voltage range as in the second embodiment, the second voltage converter 7 boosts the voltage in the direction from the first end to the second end. The voltage converter 2 only needs to be able to step down in the direction from the second end to the first end in the reverse direction, and the voltage converter 2 steps down the voltage in the direction from the first end to the second end, and from the second end to the first end in the reverse direction. In the direction, the voltage can be increased only. By selecting such a voltage level, these voltage converters can have a simpler configuration.

  Next, the operation of the vehicle power source device according to Embodiment 3 of the present invention will be described. The flowchart showing the processing executed at a constant cycle in the vehicle power supply device according to Embodiment 3 of the present invention may be the same as that in Embodiment 2 (FIG. 11), and only part of the processing contents are different. It is. For this reason, the following description will focus on differences from the second embodiment.

  In FIG. 11, the power generation execution determination process by the power generation execution determination unit 65 and the charge power calculation process by the charge power calculation unit 66 in steps S401 and S402 may be the same processes as in the second embodiment.

  The required output power calculation process by the required output power calculation unit 60 in step S403 may be the same as that in the second embodiment when the second end is the output side when it is determined to generate power. The processing when power generation is not performed will be described later together with the second required output power calculation processing by the second required output power calculation means 67.

  The second required output power calculation process in step S404 may be basically the same as that of the second embodiment when the second end is the output side when it is determined to generate power. However, since the voltage converter 2 and the lead battery 3 are not connected to the second end of the second voltage converter 7 as in Embodiment 2, it is not necessary to consider the required output power. As described above, the processing when power generation is not performed will be described later together with the required output power calculation processing.

  Here, the required output power calculation process and the second required output power calculation process when power generation is not performed will be described. When the lithium ion battery 8 is not charged, power is supplied from the lithium ion battery 8 to the load feeding bus 5 via the second voltage converter 7 and the voltage converter 2, while the lithium ion battery 8 8 is supplied from the lead battery 3 to the lithium ion battery 8 via the voltage converter 2 and the second voltage converter 7. Therefore, unlike the second embodiment, in any case, power is transferred via the voltage converter 2 and the second voltage converter 7, and the loss in both voltage converters 2 and 7 increases. There is a fear.

  Therefore, a method for reducing loss in the voltage converter will be described. FIG. 13 shows an example of a circuit diagram of the internal configuration of voltage converter 2 in the vehicle power supply device according to Embodiment 3 of the present invention. As described above, the voltage is stepped down in the direction from the first end to the second end, and is a known chopper circuit composed of MOSFETs 20 and 21 serving as switching elements and a coil 22, and the MOSFETs 20 and 21 are driver circuits (not shown). ON / OFF at. The capacitors 23 and 24 are for smoothing. Incidentally, the second voltage converter 7 has the same configuration although the voltage conversion is reversed.

  In this configuration, the voltage converter control means 2a performs voltage conversion by controlling the driver circuit and changing the ON time ratio between the MOSFET 20 and the MOSFET 21. For example, the shorter the ON time of the MOSFET 20, the greater the voltage conversion ratio.

  Further, when the voltage conversion operation is stopped and the MOSFET 20 is always ON and the MOSFET 21 is always OFF, the first end and the second end are always in a conductive state. In this state, there is no ON / OFF switching of the MOSFET, so that no switching loss occurs and the coil 22 passes, but the loss of the voltage converter can be greatly reduced.

  Therefore, when power generation is not performed, loss can be reduced by stopping the voltage conversion operation of one voltage converter and performing voltage conversion using only the remaining one voltage converter. In the third embodiment, since the voltage range of the first end of the voltage converter 2 is 14 to 28V and the operating voltage range of the lithium ion battery 8 is 30 to 42V, the voltage conversion operation of the voltage converter 2 is stopped. The voltage conversion is performed only by the second voltage converter 7. This is because it is not necessary to change the operating voltage of the voltage converter 2.

  In this case, first, since the power is supplied from the lithium ion battery 8 to the load feeding bus 5 except when the lithium ion battery 8 is charged, in the required output power calculation process (step S403), the second end of the voltage converter 2 is What is necessary is just to obtain | require the required value which is an output side or voltage required by the method similar to Embodiment 2 on the output side. However, the voltage converter control means 2a is instructed to stop the operation of the voltage converter 2.

  In the second required output power calculation process (step S404), since the voltage converter 2 has stopped operating, the output current or output voltage at the first end on the output side of the second voltage converter 7 becomes the required value. In addition, since the second voltage converter control means 7a only needs to be able to control the second voltage converter 7, the required value may be set as the second required value. As a result, the output current or output voltage at the second end of the voltage converter 2 is controlled to the required value.

  On the other hand, when the lithium ion battery 8 is charged, power is supplied from the lead battery 3 to the lithium ion battery 8, so that the required output power calculation process (step S403) is performed by the voltage converter 2 on the voltage converter control means 2a. It is only necessary to give an instruction to stop the operation. In the second required output power calculation process (step S404), the output current or the output voltage required for the second end of the second voltage converter 7 on the output side based on the charging power is used. A certain second required value may be calculated.

  In the third embodiment, one of the voltage converters is stopped to reduce the loss. However, depending on the configuration of the voltage converter, the voltage conversion range, etc., it is more lossy to operate both voltage converters. It can also be reduced. In this case, the required value and the second required value that minimize the total loss may be calculated in consideration of the loss characteristics of each voltage converter. Further, since the voltage converter is passed twice, it goes without saying that the required value may be calculated in consideration of the loss due to the other voltage converter.

  The power generation allowable torque setting process, the target generated power calculation process, and the target generated voltage setting process from step S405 to step S407 are performed except that the second required output power is used in addition to the required output power in the target generated power calculation process. It may be equivalent to the second embodiment. The generator control process in step S408 may be the same as that in the second embodiment.

  As described above, in the vehicle power supply device according to Embodiment 3 of the present invention, the second voltage converter 7 and the lithium ion battery 8 connected in parallel with the voltage converter 2, the second required output power calculation means 67. And the second voltage converter control means 7a and the power generation execution determination means 65, the second required output power calculation means 67 is in the state of charge of the lithium ion battery 8 when it is determined to generate power. And / or the output current or output voltage required at the second end of the second voltage converter 7 based on the running state of the vehicle as the second required value, and the required output power related to the second required value as the second required output. The target generated power calculation means 62 calculates the target generated power based on the required output power obtained by adding the second required output power to the required output power, and determines that power generation is not performed. In this case, the generator control means 64 controls the generator 1 so that the generated power of the generator 1 becomes 0, and the voltage converter control means 2a and the second voltage converter control means 7a By controlling the voltage converter 2 and the second voltage converter 7 so that the output current or the output voltage at the second end of the second voltage becomes the required value, the second voltage converter 7 and the voltage converter 2 can be changed from the lithium ion battery 8. Since power is supplied to the lead battery 3 and the on-vehicle electric load 4 via the power supply, power can be supplied to the voltage converter 2 without generating power, and power can also be stored in the lithium ion battery 8 during power generation. Therefore, it is possible to actively generate power during regenerative power generation during deceleration, and to reduce the fuel used for power generation by prohibiting power generation as much as possible in other conditions It is possible to reduce the cost improvement.

  Furthermore, when it is determined that the power generation is not performed and the charging power is calculated by the charging power calculation unit 66, the second required output power calculation unit 67 performs the second voltage conversion based on the charging power. The output current or output voltage required at the second end of the converter 7 is calculated as a second required value, and the voltage converter control means 2a and the second voltage converter control means 7a Since the voltage converter 2 and the second voltage converter 7 are controlled so that the output current or output voltage at the end becomes the second required value, the voltage converter 2 and the second voltage converter 7 are changed from the lead battery 3. Therefore, the lithium ion battery 8 can be smoothly charged by supplying power through the battery.

  In each embodiment, the lead battery 3 is used as the power storage device and the lithium ion battery 8 is used as the second power storage device. However, the present invention is not limited to this, and a capacitor may be used. In addition, although there is no electric load of the vehicle that is directly connected to the second power storage device, it is advantageous to increase the voltage in a load that requires a large amount of power, such as electric power steering, for example. May be.

  Further, instead of the generator, a motor generator may be used. As described above, a motor generator may be used instead of the belt connection, for example, a pinch connection between the internal combustion engine and the transmission. In this case, if the power generation voltage such as HEV is a high voltage, the voltage may be stepped down to the voltage suitable for the electric load of the vehicle with two voltage converters as in the second embodiment. Further, in the third embodiment, when the voltage converter is controlled so that the first end and the second end of one voltage converter are always in a conductive state, the voltage conversion ratio is increased, and if the loss is increased, the efficiency is increased. What is necessary is just to control both voltage converters so that it may improve.

  It should be noted that the present invention can be freely combined with each other within the scope of the invention, and each embodiment can be appropriately modified or omitted.

1 generator, 2 voltage converter, 2a voltage converter control means, 3 lead battery,
4 onboard electric load, 5 load feeding bus, 6, 6A control unit,
60 required output power calculation means, 61 power generation allowable torque setting means,
62 target generated power calculation means, 63 target generated voltage setting means, 64 generator control means,
65 power generation execution determination means, 66 charging power calculation means, 67 second required output power calculation means, 7 second voltage converter, 7a second voltage converter control means, 8 lithium ion battery,
10 accelerator sensor, 11 brake switch, 12, 13 battery sensor,
20, 21 MOSFET, 22 coil, 23, 24 capacitor.

Claims (12)

A power generator that generates electric power using vehicle travel energy or internal combustion engine energy as a drive source, a power storage device that stores electric power generated by the generator and supplies electric power to the electric load of the vehicle, and a first end is the In the vehicle power supply device comprising a voltage converter connected to the generator and having a second end connected to the electric load,
Torque that can be used for power generation of the generator, that is, power generation allowable torque that is set so as not to affect the drivability of the vehicle even if power generation is stopped, which is a torque that the generator uses for power generation A torque setting means,
The maximum power that can be generated by the generator at the rotational speed of the generator and the maximum power that can be generated by the generator at the rotational speed of the generator. When the electric power that can be generated is equal to or greater than the maximum generated electric power, the generator is operated at the maximum electric power generated, and when the electric power that can be generated is less than the maximum electric power generated, the generator A power supply device for a vehicle, wherein the generator and the voltage converter are controlled to operate with the power that can be generated at the maximum power generation efficiency. A generator that generates electric power using vehicle travel energy or internal combustion engine energy as a drive source; a power storage device that stores electric power generated by the generator and supplies electric power to the electric load of the vehicle; An output current required for the second end of the voltage converter based on a voltage converter connected to the machine and having a second end connected to the electric load, a charging state of the power storage device and / or a running state of the vehicle, or Required output power calculating means for calculating a required value that is output voltage and required output power that is output power related to the required value, target generated power calculating means for calculating target generated power of the generator based on the required output power, Target generation voltage setting means for setting a target generation voltage of the generator based on the target generation power, and the generation voltage so that the generation voltage of the generator becomes the target generation voltage. A power supply for a vehicle comprising generator control means for controlling the machine, and voltage converter control means for controlling the voltage converter so that an output current or output voltage at the second end of the voltage converter becomes the required value In the device
Torque that can be used for power generation of the generator, that is, power generation allowable torque that is set so as not to affect the drivability of the vehicle even if power generation is stopped, which is a torque that the generator uses for power generation A torque setting means,
The target generated power calculation means is configured to generate power at the generator's rotational speed and the generator's rotational speed at the generator's rotational speed when the generator allowable torque is used at the rotational speed of the generator. Calculating the maximum generated power that is the maximum power that can be generated and the maximum power generated voltage that is the generated voltage when the maximum generated power is reached, and the minimum power among the requested output power, the power that can be generated, and the maximum generated power Is calculated as the target generated power,
The target generated voltage setting means sets the maximum power generated voltage as the target generated voltage when the target generated power is equal to the maximum generated power, and when the target generated power is smaller than the maximum generated power, Based on the rotational speed of the generator and the target generated power, the maximum efficiency generated voltage that is the generated voltage that maximizes the power generation efficiency of the generator is calculated, and the maximum efficiency generated voltage is set as the target generated voltage. A power supply device for a vehicle. Setting the set range of the target power generation voltage and the voltage range of the power storage device so that the voltage conversion from the first end to the second end of the voltage converter is in either the step-up direction or the step-down direction. The power supply device for a vehicle according to claim 2. A second voltage converter having a first end connected to the generator and a second end connected to the voltage converter and inserted between the generator and the voltage converter; and the second voltage converter A second power storage device connected in parallel to the power storage device connected via the voltage converter at the second end, an output current or an output voltage required for the second end of the second voltage converter A second required output power calculating means for calculating a second required output power that is a second required value and an output power related to the second required value; an output current or an output voltage at the second end of the second voltage converter; The second voltage converter control means for controlling the second voltage converter so that the second required value becomes the second required value, and the generator generates power based on the charge state of the second power storage device and / or the running state of the vehicle. Power generation execution determination means for determining whether or not to execute Provided,
When it is determined by the power generation execution determining means that the power generation is performed, the second required output power calculating means is configured to determine the second required output power based on the charge state of the second power storage device and / or the running state of the vehicle and the required output power. An output current or output voltage required at the second end of the voltage converter is calculated as the second required value, and a required output power related to the second required value is calculated as the second required output power, and the target power generation The power calculation means calculates the target generated power based on the second required output power instead of the required output power,
When it is determined that power generation is not performed by the power generation execution determination unit, the generator control unit controls the generator so that the generated power of the generator becomes 0, and the voltage converter control unit includes: By controlling the voltage converter so that the output current or output voltage at the second end of the voltage converter becomes the required value, the power storage device and the electricity from the second power storage device via the voltage converter 4. The vehicle power supply device according to claim 2, wherein electric power is supplied to the load. The voltage converter is configured to be able to output bidirectionally, and charging is performed when the second power storage device needs to be charged by the power storage device based on the state of charge of the power storage device and the second power storage device. Charging power calculation means for calculating power,
When it is determined that power generation is not performed by the power generation execution determining unit, and the charging power is calculated by the charging power calculating unit, the required output power calculating unit is configured to output the first output of the voltage converter based on the charging power. The output current or output voltage required at the end is calculated as the required value, and the voltage converter control means is configured to output the voltage so that the output current or output voltage at the first end of the voltage converter becomes the required value. 5. The vehicle power supply according to claim 4, wherein the second power storage device is charged by supplying power from the power storage device to the second power storage device via the voltage converter by controlling a converter. apparatus. A second power storage device, a second voltage converter having a first end connected to the generator and a second end connected to the second power storage device, capable of bi-directional output, and the second voltage converter. A second request value that is an output current or output voltage required for an output terminal of one end or the second end and a second request output power that is an output power related to the second request value are calculated. 2 required output power calculation means, the second voltage conversion so that an output current or an output voltage of a terminal on the output side of the first end or the second end of the second voltage converter becomes the second required value. A second voltage converter control means for controlling the generator, and a power generation execution judging means for judging whether or not to generate power by the generator based on a charging state of the second power storage device and / or a running state of the vehicle. ,
When it is determined by the power generation execution determining means that the power generation is performed, the second required output power calculating means is configured to determine the second voltage converter based on the state of charge of the second power storage device and the traveling state of the vehicle. The output current or output voltage required at the second end is calculated as the second required value, and the required output power related to the second required value is calculated as the second required output power. Calculating the target generated power based on the required output power obtained by adding the second required output power to the required output power;
When it is determined by the power generation execution determination means that power generation is not performed, the generator control means controls the generator so that the generated power of the generator becomes zero, and the voltage converter control means and the The second voltage converter control means controls the second voltage converter and the second voltage converter by controlling the voltage converter and the second voltage converter so that the output current or output voltage of the second end of the voltage converter becomes the required value. 4. The vehicle power supply device according to claim 2, wherein electric power is supplied from the power storage device to the power storage device and the electric load via the second voltage converter and the voltage converter. 5. The voltage converter is configured to be able to output bidirectionally, and charging is performed when the second power storage device needs to be charged by the power storage device based on the state of charge of the power storage device and the second power storage device. Charging power calculation means for calculating power,
When it is determined that power generation is not performed by the power generation execution determination unit and the charging power is calculated by the charging power calculation unit, the second required output power calculation unit is configured to use the second voltage converter based on the charging power. An output current or output voltage required at the second end of the second voltage converter is calculated as the second required value, and the voltage converter control means and the second voltage converter control means By controlling the voltage converter and the second voltage converter so that the output current or output voltage at two ends becomes the second required value, the power storage device passes through the voltage converter and the second voltage converter. The vehicle power supply device according to claim 6, wherein power is supplied to the second power storage device to charge the second power storage device. When it is determined that the power generation execution determination unit does not perform power generation, either the voltage converter control unit or the second voltage converter control unit is configured such that the voltage converter or the second voltage converter 8. The vehicle power supply device according to claim 6, wherein control is performed so that the first end and the second end are always in a conductive state. Setting range of the target power generation voltage and the power storage device so that voltage conversion from the first end to the second end of the voltage converter and the second voltage converter is in either the step-up direction or the step-down direction. The vehicle power supply device according to claim 4, wherein a voltage range of the second power storage device is set. The power generation allowable torque setting means is configured such that a change in deceleration of the vehicle that occurs when the power generation is stopped in a process in which the vehicle decelerates by generating power using the traveling energy of the vehicle as a drive source is within a predetermined value. The vehicular power supply device according to any one of claims 1 to 9, wherein the power generation allowable torque is set so that The vehicle power supply device according to any one of claims 1 to 10, wherein the power generation allowable torque setting means sets the power generation allowable torque so that the power generation allowable torque decreases as the rotational speed of the generator increases. The vehicle power supply device according to any one of claims 1 to 11, wherein the power generation allowable torque setting means sets the power generation allowable torque so as to increase as the speed of the vehicle increases.

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