JP5219026B2 - Vehicle power generation control device - Google Patents

Description

  The present invention relates to a vehicle power generation control device configured by combining an alternator, a starter, and a battery. More specifically, the present invention relates to a configuration in which an energy storage capacitor is added to effectively use energy of an alternator to improve fuel efficiency.

  Generally, a vehicle power generation control device mounted on a vehicle (automobile) is configured by combining an alternator, a starter (cell motor), and a battery (mainly lead storage battery).

  The energy of the battery is mainly used for starting the engine by the starter. After the engine is started, the rectified power generation output of the alternator is mainly used for charging the battery and driving the load (general load) in the vehicle. The output voltage of the alternator is switched between high and low by automatic adjustment based on the voltage monitoring of the battery. For example, in the case of an alternator for a vehicle equipped with a battery with a rated voltage of 12 V, the voltage is increased to 14.5 V when charging the battery. After charging, in principle, the voltage becomes a low voltage (open voltage) of 12.8 V while the battery is maintained in a fully charged state by floating charging.

  Incidentally, in recent years, it has been proposed to further improve fuel efficiency by further providing a large-capacity capacitor in the vehicle power generation control device (see, for example, Patent Document 1).

  In this case, after the battery is charged by the high voltage power generation output of the alternator, the vehicle decelerates while the load is fed and driven while the battery is maintained in a fully charged state by the low voltage power generation output of the alternator. In order to effectively use the engine output during deceleration, the output voltage of the alternator is switched to the high voltage, the capacitor is charged with the surplus power output of the alternator, and when deceleration is completed, the output voltage of the alternator is reduced to the low voltage. The stored energy of the capacitor is preferentially supplied to the general load to improve fuel efficiency.

JP 2006-87163 A (abstract, paragraphs [0015], [0028]-[0031], [0055]-[0063], [0066]-[0067], FIG. 1, FIG. 6, etc.)

  In the case of the configuration described in Patent Document 1, the battery and the capacitor are each connected to a power supply line to the load via a backflow prevention diode (or FET) in order to supply power to the vehicle load. In this case, an energy loss due to a voltage drop in the forward direction of the diode (or FET) occurs, and the fuel efficiency improvement effect is reduced accordingly. Further, a space for providing a diode or FET is required, which increases the size and cost.

  Therefore, it is conceivable that the vehicle power generation control device including the capacitor is configured as shown in FIG.

  In FIG. 4, 1 is a known alternator, its output terminal 1p is connected to the main power supply line 2 for load power supply, its ground terminal 1n is grounded to the vehicle body frame via the engine block, and according to the rotation of the engine The generated alternating current is rectified to form a power generation output.

  Each load line 4 of the relay box 3 is connected to the feeder line 2 in a branched shape. Each load line 4 is connected to a general load 7 such as an in-vehicle lamp or an air conditioner via a fuse 5 and a relay switch 6 in the relay box 3. Note that the relay coil and the like in the relay box 3 are not shown.

  Further, a positive terminal 8 p of a battery 8 with a rating of 12 V mounted on the vehicle is connected to the feeder line 2 via a fuse 9. The negative terminal 8n of the battery 8 is grounded to the body frame.

  A starter 10 is provided between terminals 8p and 8n of the battery 8 via a starter switch 10a, and the starter 10 is connected to the battery 8 in parallel via a starter switch 10a.

  Further, one end of a large capacity energy storage capacitor 11A is connected to the terminal 8p of the battery 8, the other end of the capacitor 11A is grounded to the vehicle body frame, and the capacitor 11A is connected to the battery 8 in parallel.

  Then, when the engine is started by turning the ignition key, the starter switch 10a is closed and the starter 10 is driven by the energy of the battery 8.

  When the engine is started by the starter 10, the alternator 1 generates power. At this time, the starter switch 10 a is opened, and the starter 10 is disconnected from the power supply line 2 and the battery 8.

  When the charged state of the battery 8 is lowered from a fully charged state of approximately 100% due to the engine start discharge, the power generation output of the alternator 1 becomes the high voltage, and the battery 8 is charged by this high voltage power generation output (constant voltage charging). Is done. As the battery 8 is charged, the internal impedance increases and the charging current hardly flows.

  When the battery 8 is fully charged, thereafter, the battery 8 only needs to be maintained in a fully charged state. Therefore, the power generation output of the alternator 1 is based on the state monitoring (current and voltage monitoring) of the battery 8. Switch to low voltage. In addition, each load 7 is driven to be fed by the power generation output of the alternator 1. At this time, the battery 8 is substantially neither charged nor discharged, and fluctuations in the power generation output of the alternator 1 are absorbed by the battery 8.

  Next, when deceleration occurs while the battery 8 is maintained in a fully charged state, the power generation output of the alternator 1 is switched to the high voltage in order to effectively use the engine output during deceleration. The capacitor 11A is charged by the generated output.

  When the deceleration is completed, the power generation output of the alternator 1 returns to the low voltage. At this time, since the charging voltage of the capacitor 11A is high, the energy accumulated in the capacitor 11A is preferentially supplied to each load 7, and the power generation load of the alternator 1 is reduced accordingly.

  In the case of the configuration of FIG. 4, the backflow prevention diode (or FET) is not provided, so there is no energy loss due to the forward voltage drop, and miniaturization and cost reduction can be achieved. is there.

  However, the capacitor 11 </ b> A is provided closer to the battery 8 than the feeder line 2 and is connected to the battery 8 in parallel. Therefore, the stored energy of the capacitor 11 </ b> A charged with the power generation output of the alternator 1 via the feeder line 2 is reduced by the amount of impedance loss of the feeder line 2. Further, the power generation output of the alternator 1 is also fed in parallel to the fully charged battery 8 via the feeder line 2, thereby reducing the stored energy of the capacitor 11A. Therefore, the power generation output of the alternator 1 is not sufficiently effectively used, and the fuel efficiency improvement effect cannot be improved.

  In the field of vehicles, it is extremely important and desirable to improve the fuel efficiency improvement effect and effectively use resources, from the viewpoints of economy, resources, environmental protection, and the like.

  An object of the present invention is to provide a capacitor for storing energy with a small and inexpensive configuration and to effectively use the power generation output of an alternator as much as possible to enhance the fuel efficiency improvement effect.

In order to achieve the above object, a vehicle power generation control device of the present invention includes an alternator, a battery, a starter, and an energy storage capacitor, and the alternator is connected to a main power feed line for load power feed. The battery is connected to the alternator through the power supply line, the starter is connected in parallel to the battery, and the capacitor is connected in parallel to the alternator on the alternator side from the power supply line, In addition, a current-limiting resistor is interposed between the alternator and the battery and between the power supply line and the battery (claim 1).

Further, in order to use the energy of the power generation output of the alternator more effectively, it is closed in parallel with the current-limiting resistor and in a state where power is supplied from the battery to the power supply line side to form a bypass path for the resistor. It is desirable that an opening / closing means is provided (Claim 2 ).

In the vehicle power generation control device according to the first aspect of the present invention, since the energy storage capacitor is connected in parallel to the alternator on the alternator side of the main power supply line of the load power feeding, the surplus of the alternator during deceleration or the like The power generation output is stored in the capacitor without being affected by the impedance loss of the power supply line, and then supplied to a load connected to the power supply line. In addition, since a current-limiting resistor is interposed between the alternator and the battery and between the power supply line and the battery , the power generation output of the alternator is at a high voltage during deceleration when the battery is maintained in a fully charged state. Even when the mode is switched to, useless power feeding to the battery side is prevented, and the surplus power generation output can be accumulated in the capacitor without further waste.

  Since the diode (or FET) for preventing backflow described in Patent Document 1 described above is not provided, there is no energy loss due to a forward voltage drop of the diode (or FET), and miniaturization and cost reduction are achieved. It is possible to plan.

  Therefore, the power generation output of the alternator can be used as effectively as possible with a small and inexpensive configuration, and fuel consumption can be improved.

In the case of the vehicle power generation control device according to the second aspect of the present invention, it is impossible to cover the power generation output of the alternator alone due to a sudden increase in the load, etc., and it is necessary to supply power from the battery to the power supply side. energy, without passing through the resistance of the limit diverted, fed to the load through the bypass passage of the closing means. Therefore, the stored energy of the battery can be supplied from the battery to each load on the power supply line without loss due to the current limiting resistor. Since the battery is charged by the power generation output of the alternator, the power generation output of the alternator can be more effectively used to further improve the fuel efficiency improvement effect.

  Next, in order to describe the present invention in more detail, the embodiment will be described in detail with reference to FIGS.

(One embodiment)
An embodiment corresponding to the inventions of claims 1 and 2 will be described with reference to FIGS.

  FIG. 1 is a connection diagram of the present embodiment, and FIG. 2 is a connection diagram of an apparatus configuration that is the basis of the configuration of FIG. 1. In these drawings, the same reference numerals as those in FIG.

  As shown in FIG. 2, the vehicle power generation control device of the present embodiment is first connected in parallel to the alternator 1 on the alternator 1 side of the feeder line 2 instead of the capacitor 11 </ b> A parallel to the battery 8 of FIG. 4. The large-capacity energy storage capacitor 11B is provided. Therefore, for example, surplus power generation output of the alternator 1 that has been switched to the high voltage during deceleration is accumulated in the capacitor 11B without being affected by impedance loss of the feeder line 2. In consideration of safety and the like, a fuse 12 is provided between the output terminal 1p of the alternator 1 and one end of the capacitor 11B. However, in some cases, the fuse 12 may be omitted. The other end of the capacitor 11B is grounded to the vehicle body frame.

  Then, the power generation output of the alternator 1 can be efficiently stored in the capacitor 11B simply by configuring as shown in FIG. 2 so that the energy storage (charging) of the capacitor 11B is not affected by the impedance loss of the feeder line 2. However, the vehicle power generation control device of the present embodiment secondly has a current limiting resistor 13 interposed between the alternator 1 and the battery 8 so that the surplus power generation output of the alternator 1 is not leaked to the capacitor 11B. Accumulate and use the power generation output of the alternator 1 more effectively.

  Specifically, as shown in FIG. 1, a current-limiting resistor 13 is interposed between the power supply line 2 and the fuse 9, which is between the power supply line 2 and the positive terminal 8 a of the battery 8.

  With this configuration, after the battery 8 is charged, the power generation output of the alternator 1 returns to the low voltage, and deceleration occurs while the battery 8 is maintained in a fully charged state with little charging or discharging. Even if the power generation output of 1 is switched from the low voltage to the high voltage, the current to the battery 8 side is limited by the resistor 13 and unnecessary power feeding is prevented. Therefore, the surplus power generation output of the alternator 1 that has been switched to the high voltage due to the deceleration is accumulated in the capacitor 11B without leakage.

  Although the resistor 13 has a low resistance value, its resistance value and the like are based on experiments and the like, such as impedance loss during charging of the capacitor 11B, fuse fusing property due to short current of the battery 8 (allowable current of the fuse), and the like. Set in consideration.

  When deceleration is completed and the power generation output of the alternator 1 returns to the low voltage, the high voltage stored energy of the capacitor 11B is preferentially supplied to each load 7, and the power generation load of the alternator 1 is reduced accordingly. The For this reason, the opportunity for separating the alternator 1 from the engine and controlling it to the so-called “alter cut” increases, and the fuel efficiency is improved and improved.

  Thirdly, the vehicle power generation control device of this embodiment is provided with a switch 14 for disconnecting the capacitor 11B to reliably prevent the fuse 12 from being blown or the resistor 13 from being burned out by a large current at the time of engine start or the like. Ensure safety during maintenance and maintenance. The switch 14 is specifically provided between the alternator 1 and the capacitor 11B, more specifically, between the output terminal 1p of the alternator 1 and the fuse 12.

  In order to prevent the fuse 12 from being blown or the resistor 13 from being burned by a large current (starter current) when the engine is started, the switch 14 is opened (off) and closed (on) in conjunction with, for example, switching of the ignition key. . That is, the switch 14 is closed when the ignition is turned on (engine start) and opened when the ignition is turned off or the engine is stopped.

  Therefore, the capacitor 11B is connected to the power supply line 2 via the fuse 12 only after the engine is started and until the engine is stopped, and is disconnected from the power supply line 2 when the engine is started. Therefore, when the engine is started, a large current of the energy stored in the capacitor 11B does not flow to the starter 10 through the fuse 12 and the resistor 13.

  In addition, when the capacitor 11B is attached, inspected or replaced during manufacturing or maintenance inspection, if the discharged capacitor 11B is inadvertently connected to the power supply line 2, the battery 8 passes through the resistor 14 and the fuse 12. A large current (charging current) flows instantaneously through the capacitor 11B, and a spark may occur depending on the capacitance of the capacitor 11B.

  In the case of a configuration that avoids such a situation, the switch 14 is formed by a switch that can be opened and closed even by manual operation.

  When attaching or inspecting or replacing the capacitor 11B, the switch 14 is opened before the work is started, and the switch 14 is closed after the work is finished, so that the capacitor 11B is not charged until the switch 14 is closed. And safety during maintenance management.

  Therefore, in the case of the present embodiment, by using a small and inexpensive configuration, the surplus power generation output of the alternator 1 while the battery 8 is maintained in a substantially fully charged state is accumulated in the capacitor 11B without leakage and used as effectively as possible. Can improve fuel efficiency.

  Further, by providing the switch 14, it is possible to improve the reliability by preventing the fuse 12 from being blown and the resistor 13 from being burned at the time of starting the engine, and to improve the safety at the time of manufacturing and maintenance management.

  Depending on the capacity of the capacitor 11B and the like, even if the capacitor 11B is connected to the power supply line 2 when the engine is started, the fuse 12 is not blown or the resistor 13 is not burned. In this case, the switch 14 is a normally closed switch that can be opened and closed only by manual operation, the switch 14 is kept closed when the engine is started, and the switch 14 is closed only during manufacturing and maintenance management to improve safety. It may be. Further, when the configuration is simplified, the switch 14 may be omitted.

(Other embodiments)
Another embodiment corresponding to the invention of claim 3 will be described with reference to FIG.

  FIG. 3 is a connection diagram of the present embodiment, in which the same reference numerals as those in FIGS. 1 and 2 indicate the same or corresponding components.

  The vehicle power generation control device of FIG. 3 of the present embodiment is different from the vehicle power generation control device of FIG. 1 in that a normally-open switch 15 for a bypass that forms the opening / closing means of the present invention is provided in parallel with the resistor 13. On the basis of the detection result of the current sensor 16 for detecting the charge / discharge current of the battery 8, the switch 15 is controlled to be opened and closed by the ECU 17 for controlling the electronically controlled fuel injection of the microcomputer configuration.

  The current sensor 16 detects the current direction (charge / discharge) and current amount of the battery 8 every moment.

  Then, for some reason such as a sudden increase in the load of the power supply line 2 during traveling of the vehicle, the power generation output of the alternator 1 cannot cover the load power supply, and the voltage of the load power supply decreases and current flows from the battery 8 toward the power supply line 2 When the flow starts, the ECU 17 recognizes a state where power is supplied from the battery 8 to the power supply line 2 side based on a change in the detection result of the current sensor 16 and closes the switch 15 to form a bypass path of the resistor 13.

  Therefore, the current of the energy stored in the battery 8 passes through the bypass path of the switch 15 and is fed to the feeder line 2 without loss (voltage drop) at the resistor 13.

  When the power generation output of the alternator 1 can cover the load power supply, the ECU 17 recognizes the state from the change in the detection result of the current sensor 16, and opens the switch 15 after charging the capacitor 11B.

  Therefore, in the case of the present embodiment, there is an advantage that the stored energy of the battery can be supplied from the battery 8 to each load 7 on the power supply line 2 side without loss at the resistor 13.

Since the battery 8 is charged by the power generation output of the alternator 1, the stored energy of the battery 8 is supplied from the battery 8 to each load 7 on the power supply line 2 side without loss at the resistor 13, thereby generating power from the alternator 1. using the output more efficiently the effects of improving fuel efficiency can be further improved.

  The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention.

  For example, the high voltage and the low voltage of the alternator 1 are set according to the rated voltage of the battery 8 and are not limited to the size of the embodiment.

  Further, the capacity of the capacitor 11B may be set based on the design condition of the load amount, and the switch 14 may be provided between the capacitor 11B and the fuse 12, for example.

  Further, the configuration of each load line 4 branched from the feeder line 2 may be any.

  The present invention can be applied to a vehicle power generation control device mounted on various vehicles.

It is a connection diagram of one embodiment of the present invention. FIG. 2 is a connection diagram of the configuration that is the basis of FIG. 1. It is a connection diagram of other embodiments of the present invention. It is a connection diagram of the example of an apparatus provided with the capacitor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Alternator 2 Feed line 7 Load 8 Battery 10 Starter 11B Energy storage capacitor 13 Current limiting resistor 15 Bypass switch

Claims (2)

An alternator, a battery, a starter, and an energy storage capacitor;
The alternator is connected to a main power supply line for load power supply,
The battery is connected to the alternator through the feeder line,
The starter is connected in parallel to the battery;
The capacitor is connected in parallel to the alternator on the alternator side from the feeder line,
The vehicle power generation control device is characterized in that a current-limiting resistor is interposed between the alternator and the battery and between the power supply line and the battery . The vehicle power generation control device according to claim 1 ,
A vehicular power generation control device is provided in parallel with the current-limiting resistor, and is provided with opening / closing means that is closed when the battery feeds power from the battery to the feeder line side and forms a bypass path for the resistor. .

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