JPH1169651A - Power device for car - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve cooling performance without changing the specifications of an electrically driven cooling means, by providing a regulating voltage automatic changing means for setting the regulating voltage value of a voltage regulator at the time of the operation of the electrically driven cooling means at a value higher than the time of the nonoperation of the electricallty driven cooling means. SOLUTION: Generated voltage at the time of the operation of a motor (an electrically-driven cooling means) 6 for a radiator fan is set at a value higher than the time of the nonoperation of the motor 6, and a regulating- voltage automatic changeover circuit (a regulating-voltage automatic changing means) is composed of a switching element 106 altering the voltage-dividing ratio of a voltage-dividing resistor and a temperature switch 5. Accordingly, since power applied to the motor 6 is increased, a cooling effect can be improved without augmenting the capacity of the radiator fan.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a vehicular power device used for an automobile or the like, and more particularly to a technique for controlling power supply to a cooling motor of an internal combustion engine.

[0002]

2. Description of the Related Art An electric power device such as an automobile using an internal combustion engine as a power source includes a generator driven by the engine, and a battery charged by the output of the generator. Detected power generation voltage (battery voltage)
The generator excitation current is controlled so that the target adjustment voltage becomes the target adjustment voltage.

Further, in the power generation control device for a vehicle generator described in Japanese Patent Publication No. 1-39306, the signals of a plurality of sensors (sensor signals for detecting the state of the battery, a power engine The target adjustment voltage of the generator output is calculated in accordance with the sensor signal for detecting the operation state, and the generator excitation winding (the armature winding output) is adjusted so that the generator output (the armature winding output) matches the target adjustment voltage value. A technique for controlling the amount of current flowing through a field winding has been proposed.

In such a conventional vehicle power device, there is no particular correlation with a cooling system electric motor (for example, a motor of a radiator fan) of an internal combustion engine, and with respect to the radiator fan, a temperature of a cooling fluid (engine cooling water) of the engine is reduced. Is generally detected, and the radiator fan is turned on and off so that the cooling water temperature does not exceed a predetermined temperature.

[0005]

In recent years, internal combustion engines for passenger cars have become narrower due to increased driving force and addition of exhaust countermeasures, resulting in higher operating temperatures and, on the other hand, improved appearance of automobiles. Therefore, there is a problem that the cooling system of the internal combustion engine cannot be enlarged. For this reason, there is a demand for a small and high-power electric cooling means such as a radiator fan for cooling the engine cooling water by wind.

SUMMARY OF THE INVENTION An object of the present invention is to provide an electric power device for a vehicle capable of increasing the cooling performance without changing the specifications of an electric cooling means such as a radiator fan, that is, without increasing the size of the electric cooling means. Is to do.

[0007]

In order to achieve the above object, according to the present invention, a generator driven by an engine, a battery charged by an output of the generator, and an output voltage of the generator are set to target values. A power regulator for controlling a generator exciting current to be adjusted to a regulated voltage value, and an electric cooling device used in a cooling system of the engine and operated in accordance with a temperature state of the engine. The present invention proposes an automatic cooling device having an automatic adjustment voltage changing means for setting the adjustment voltage value of the voltage regulator higher when the electric cooling means is operated than when the electric cooling means is not operated.

According to the above configuration, when the electric cooling means operates, the power generation voltage (battery terminal voltage) which is the driving voltage thereof is raised more than before, so that the cooling performance can be improved without changing the specifications of the electric cooling means. It is possible to increase.

The automatic adjustment voltage changing means may be, for example, electrically connected to the battery via a temperature switch which operates in accordance with the engine temperature, when the temperature switch is closed. (When the electric cooling means is activated), the adjustment voltage of the voltage regulator is set higher than when the temperature switch is open by the adjustment voltage automatic switching circuit, or the electric cooling means is set to a temperature at which the engine temperature is detected. When the engine temperature is controlled by a sensor and the engine temperature detected by the temperature sensor exceeds a predetermined value (for example, a temperature value for operating the electric cooling means), the voltage regulator is adjusted using a function circuit. A configuration in which the voltage is set to be higher can be considered.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment (first embodiment) of the present invention will be described with reference to FIG. FIG. 1 is a circuit diagram of a vehicle power device (automotive generator and its peripheral devices) according to the present embodiment.

In FIG. 1, reference numeral 1 denotes an internal combustion engine (not shown)
, A three-phase Y-connected armature winding 11a, 11b, 11c, a rectifier 12 for converting the AC output of the armature winding to DC, and an armature winding 11
It comprises a field winding (excitation winding) 13 for supplying a magnetic flux to a, 11b, and 11c, and includes a voltage regulator 10 described later.

The battery 2 is charged by the output of the armature winding 11 of the generator 1, and the electric loads 4a and 4b are connected via the switches 3a and 3b.

A temperature switch 5 detects the temperature of the cooling water of the engine (in other words, the engine temperature) and closes (conducts) when the temperature of the cooling water exceeds a predetermined value (for example, 85 ° C.).
The motor 6 of the radiator fan is electrically connected to the battery 2 via the temperature switch 5. A radiator fan (not shown) driven by the motor 6 applies wind to a radiator (not shown) of the engine to cool cooling water passing through the radiator.

The voltage regulator 10 includes a power transistor 101 and a power diode 10 connected in Darlington.
2. Comparator 103, constant voltage source 104, voltage dividing resistor 105
a, 105b, 105c, a transistor 106, and a resistor 107.

The transistor 106 is connected to the voltage dividing resistor 10 so as to function as a switching element for shorting the voltage dividing resistor.
5c is connected in parallel.

When the generator is rotating, the temperature switch 5
Is open (when the radiator fan motor 6 is not operating), the voltage of the battery 2 is divided by the voltage dividing resistors 105a and 105a.
5b, 105c, and the voltage dividing resistors 105a and 105c
When the voltage at the connection point 5b exceeds the voltage of the constant voltage source 104, the power transistor 101 is turned off via the comparator 103, the field current flowing through the field winding 13 (generator excitation current) decreases, and the power is generated. Voltage drops. Battery 2
When the terminal voltage (generation voltage) becomes low, the voltage dividing resistor 10
The voltage at the connection point between 5a and 105b falls below the voltage of the constant voltage source 104, the power transistor 101 is turned on, the field current flowing through the field winding 13 increases, and the generated voltage increases. The above operation is repeated, and the voltage of the S terminal converges to a constant voltage. This voltage is

[0017]

Vset = Vref · [1 + R105a / (R105b + R105c)] (1) where Vref: voltage of constant voltage source 104 R105a, R105b, R105c: voltage dividing resistor 10
It can be expressed as resistance values of 5a to 5c.

Next, when the temperature of the internal combustion engine rises and the temperature switch 5 is closed, the motor 6 of the radiator fan operates. At the same time, the transistor 106 is turned on via the C terminal. At this time, the regulated voltage of the generator is

[0019]

Vset ′ = Vref · (1 + R105a / R105b) (2) Here, R105c> 0, and the partial pressure ratio is R1
05a / (R105b + R105c) <R105a / R
Since it is 105b,

[0020]

Vset ′> Vset (3) Therefore, in the present embodiment, the generated voltage when the motor 6 of the radiator fan is operating (on) is higher than when the motor 6 is not operating (off). That is, the switching element 106 for changing the voltage dividing ratio of the voltage dividing resistor and the temperature switch 5 constitute an automatic adjustment voltage changing means (an automatic adjustment voltage switching circuit).

When the set value of the adjustment voltage is Vset = 14.
Assuming that 4V and Vset '= 15.9V, the electric power applied to the motor 6 at 15.9V is 1.2 times the square of (15.9 / 14.4) as compared with 14.4V. Becomes

Therefore, the cooling effect can be increased by 20% without increasing the capacity of the radiator fan.

Further, according to the present embodiment, the above-described automatic adjustment voltage switching circuit can be realized with a simple configuration of the temperature switch 5 and one transistor 106, and the cost of this kind of automatic adjustment voltage switching circuit can be reduced. obtain. In the above-described embodiment, the adjustment voltage is set in two stages. However, when the set value of the adjustment voltage is changed, if the control response characteristic that changes with a gradient is given, the rising characteristic when the output of the radiator fan is increased is obtained. Can be smooth.

Next, another embodiment (second embodiment) of the present invention.
Will be described with reference to FIG. FIG. 2 is a circuit diagram of the vehicular power device according to the present embodiment, and the components denoted by the same reference numerals as those in FIG. 1 are the same components.

The difference between this embodiment and the first embodiment is that the voltage dividing resistor 1
The adjustment voltage is set using an engine control device (microcomputer) 7 instead of the transistors 05a to 05c, the transistor 106, the comparator 103, and the like.

The motor 5 of the radiator fan has a relay 51
Is connected to the battery 2 via. 71 is an idol
ISC valve for controlling speed, 72 is an ignition coil,
73 is a spark plug. The ignition coil 72 and the ignition plug 73 controlled by the engine
Although the cylinder components are described, an ignition system is actually provided for each cylinder such as four cylinders and six cylinders. Reference numeral 74 denotes a rotation speed detector for detecting the rotation speed of the engine, which is an encoder that cuts a slit on a disk (not shown) attached to a detection target and optically generates a pulse. Reference numeral 75 denotes a temperature sensor that detects the temperature of the engine cooling water (in other words, the engine temperature), and is configured by a thermistor as an example.

Hereinafter, the power generation operation of this embodiment will be described with reference to FIGS.

FIG. 3 is a flow chart of a part related to the generator of the engine control device 7 in this embodiment. A task related to power generation control is executed at a constant cycle (for example, 10 msec). When the task of voltage control is started in step 301, the process proceeds to step 302, where the battery voltage Vs is fetched. The voltage Vs of the battery 2 is taken in via the S terminal, AD-converted and converted into a digital value. This voltage value is set as Vs and stored. Then step 3
At 03, the temperature VT of the engine cooling water is taken.

Further, in step 304, an adjustment voltage value Vset is calculated based on VT. FIG. 5 shows an example of how to set Vset with respect to the engine coolant temperature T corresponding to VT. When the water temperature T is between −30 ° C. and 85 ° C., the battery temperature is compensated with a constant (−10 mV / ° C.) temperature gradient. If the operating temperature Tset of the fan of the radiator fan motor 6 is 85 ° C., the water temperature T becomes Tset.
Is exceeded, the motor 6 operates via the relay 51 (ON).
I do. At this time, the higher the water temperature, the more rapidly the cooling water needs to be cooled, and Vset is set higher according to the temperature. However, the upper limit is a value (15.9 V in this example) that affects the life of the battery and other electric devices, and the voltage is not allowed to exceed this value. in this way,
The adjustment voltage value Vset is given in advance as a function for the cooling water temperature T, and is quantified in step 304. That is, the engine control device (microcomputer) 7
Also functions as a function circuit for increasing the adjustment voltage of the voltage regulator 10 when the engine temperature detected by the temperature sensor 75 exceeds a predetermined value.

In the next step 305, the control duty to be output is calculated. As for the control duty, feedback control is performed so as to eliminate the deviation between the adjusted voltage set value Vset obtained as described above and the actual battery voltage take-in value Vs. In this embodiment, PI (proportional / integral) control is performed on the deviation,

[0031]

D = K1 · (Vset−Vs) + K2 · ∫ (Vset−Vs) dt (4) where K1 and K2 are proportional and integral constants, respectively.

In the actual digital calculation, the previous D calculated by the voltage control task in FIG.

[0033]

D = C1 · (Vset−Vs) + C2 · Do (5) Equation (5) is equivalent to equation (4).

At step 306, the duty calculated by the equation (5) is applied to the power transistor 101 via the C terminal.
, And the current flowing through the field winding 13 is duty-controlled by the power transistor 101.

That is, the field current flowing through the field winding 13 changes according to the duty of the power transistor 101,
As a result, the voltage generated in the armature winding 11 changes, and the voltage of the battery 2 is affected via the rectifier 12.
The battery voltage Vs is feedback-controlled by the above-described software, and is adjusted to the adjustment voltage Vset.

Next, the control task of the radiator fan (cooling fan) will be described with reference to FIG. When the radiator fan control task is started in step 401, step 4
At 02, the temperature VT of the engine cooling water is taken. This VT
If the temperature exceeds the operating temperature Tset of the radiator fan described above, the flow proceeds to Yes in Step 403, and Step 4
At 04, the relay 51 is turned on. Conversely, if VT is lower than Tset, the process proceeds to step 405, where the relay 51 is turned off. In this way, the temperature of the engine cooling water becomes Tset
Will not be much higher.

In this embodiment, the radiator fan motor 6
When the engine cooling water temperature exceeds the set value Tset, the larger the deviation from the set value, the higher the adjusted voltage value becomes. The motor 6 of the radiator fan is driven, so that the cooling effect can be enhanced and the voltage control of the motor 6 with high accuracy is guaranteed. Further, the time during which the temperature of the engine compartment is high can be shortened, and the reliability of the operation and the life of the components in the engine compartment can be increased.

[0038]

As described above, according to the present invention, the cooling performance can be increased without changing the specifications of the electric cooling means, that is, without increasing the size of the electric cooling means.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of a power device for a vehicle according to a first embodiment of the present invention.

FIG. 2 is a circuit diagram of a vehicle power device according to a second embodiment of the present invention.

FIG. 3 is a flowchart illustrating an operation according to a second embodiment.

FIG. 4 is a flowchart for explaining an operation according to the second embodiment.

FIG. 5 is an explanatory diagram showing a set value for a water temperature T of a generated voltage adjustment value Vset according to a second embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Generator, 2 ... Battery, 5 ... Temperature switch, 6 ... Radiator fan motor (electric cooling means), 7 ... Engine control device (Adjustment voltage automatic change means, function circuit), 10
... voltage regulators, 11a to 11c ... armature windings, 13 ... field windings (generator excitation windings), 75 ... temperature sensors for detecting engine coolant temperature, 105a to 105c ... voltage-dividing resistors,
106: transistor for short-circuiting a voltage dividing resistor (adjustment voltage automatic change means, adjustment voltage automatic switching circuit).

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Sakae Hikida 2477 Takaba, Hitachinaka-shi, Ibaraki Prefecture Inside Hitachi Car Engineering Co., Ltd. (72) Inventor Ippei Kobayashi Nissan Motor Co., Ltd., 2 Takaracho, Kanagawa-ku, Yokohama, Kanagawa

Claims (6)

[Claims] 1. A generator driven by an engine, a battery charged by an output of the generator, and a voltage regulator for controlling a generator excitation current so that an output voltage of the generator becomes a target regulated voltage value. A power supply device for a vehicle, comprising: a cooling unit that is used in a cooling system of the engine and operates according to a temperature state of the engine. An electric power device for a vehicle, comprising an automatic adjustment voltage changing means for setting the electric cooling means higher than when the electric cooling means is not operated. 2. A generator driven by an engine, a battery charged by an output of the generator, and a voltage regulator for controlling a generator excitation current such that an output voltage of the generator becomes a target regulated voltage value. A power supply device for a vehicle, comprising: an electric cooling device that is used in a cooling system of the engine and that operates according to a temperature state of the engine. The electric cooling device includes a temperature switch that operates according to the engine temperature. An automatic adjustment voltage switching circuit that is electrically connected to the battery and that sets the adjustment voltage of the voltage regulator higher when the temperature switch is closed than when the temperature switch is open. Vehicle power device. 3. The voltage regulator has a voltage dividing resistor for detecting a generated voltage, and the automatic adjustment voltage switching circuit is configured such that when the temperature switch is closed, the voltage dividing ratio of the voltage dividing resistor is set to a value when the temperature switch is closed. 3. The electric power device for a vehicle according to claim 2, wherein the power supply device is set to be larger than when it is open, and has a circuit configuration in which the adjustment voltage increases as the division ratio increases. 4. A generator driven by an engine, a battery charged by an output of the generator, and a voltage regulator for controlling a generator excitation current such that an output voltage of the generator becomes a target regulated voltage value. A vehicle, and an electric cooling device that is used in a cooling system of the engine and that operates according to a temperature state of the engine. The electric cooling device is controlled according to a temperature sensor that detects an engine temperature. And a function circuit for increasing an adjustment voltage of the voltage regulator when an engine temperature detected by the temperature sensor exceeds a predetermined value. 5. The power device for a vehicle according to claim 1, wherein a control response characteristic of changing the set value of the adjustment voltage with a gradient is provided. 6. The power device for a vehicle according to claim 1, wherein said electric cooling means is a motor of a radiator fan.