JPH0767245B2 - Voltage regulator for vehicle charging generator - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a voltage regulator for a vehicle charging generator that sets a regulated voltage according to the state of charge of a battery and the amount of electric load on a vehicle.

[Conventional technology]

This type of voltage regulator compares the regulated voltage appropriately corrected with the battery terminal voltage to control the field winding current intermittently.

By the way, the voltage regulators that have been commonly used in the past only control the power generation state by the regulated voltage using the temperature information from the thermistor etc. as a correction parameter, so if the external electric load fluctuates significantly or the battery is charged. Depending on the quality of the state, the above-mentioned power generation control is not necessarily optimal control.

Therefore, a method is provided in which a microcomputer control device is provided, an adjusted voltage is obtained according to the battery fluid temperature information and the information on the electric load state, and the power generation state is microcomputer controlled according to the difference voltage between the adjusted voltage and the battery charging voltage. It is known as JP-A-55-58739.

[Problems to be solved by the invention]

However, in the above-described power generation control using the microcomputer control, since information on the battery charge state (for example, battery specific gravity information) is not considered, ideal power generation control is possible in all battery charge states from insufficient charge to full charge. I can't. For example, if the regulated voltage, which is the target value, is raised uniformly when the electric load is heavy, the electrolysis of dilute sulfuric acid is promoted when the battery is fully charged and when it is fully charged. Liquid electrolyte is generated.
In addition, at this time, since extra power is supplied from the generator even though the battery is in a relatively good state of charge, the life of the battery is shortened and the vehicle engine load on the generator is increased, so There was also a problem of reducing the fuel efficiency of.

In view of such a problem, the present invention provides a voltage adjusting device for a vehicle charging generator that appropriately monitors each state of charge of a battery and appropriately controls power supply to an electric load to achieve optimum charging of the battery. It is intended to be provided.

[Means for solving problems]

Therefore, as shown in FIG. 1, the voltage adjusting device of the present invention has a charge state detecting means m ₁ , a reference voltage setting means m ₂ , a load state detecting means m ₃ , a reference voltage changing means m ₄ , and a switch means m. _It consists of _six .

The charge state detecting means m ₁ detects from a fully charged state of the battery to a state of insufficient charge in a plurality of stages (at least three stages). The reference voltage setting means m ₂ sets one of the low reference voltage and the high reference voltage in accordance with the state of charge of the battery in the plurality of stages. The switching means m ₆ turns on / off the field winding current of the charging generator based on the adjustment voltage obtained from the above-mentioned respective reference voltages. The load state detecting means m ₃ detects the load state, but in the embodiment described later, for example, detects the conductivity of the switching means m ₆ and outputs a load signal. The reference voltage changing means m ₄ is
When the state of charge detecting means m ₁ detects a relatively good stage (intermediate state of charge) between the fully charged state and the insufficient charge state, the load state is detected by the load signal from the load state detection means m _3. Is detected, the reference voltage is set to a low reference voltage when it is determined to be a heavy load, and the reference voltage is set to a high reference voltage when it is determined to be a light load below that.

The switching means m ₆ compares the corrected regulated voltage value with the battery charging voltage to turn on and off the field winding current of the generator based on the comparison result.

〔The invention's effect〕

The reference voltage is set to a lower value in the vicinity of the open terminal voltage of the battery when the battery is fully charged, that is, the discharge current from the battery does not increase when the electric load is connected, and when the battery is in an insufficiently charged state. At times, it is set to a higher value that does not adversely affect the electric load and the battery. Therefore, efficient charge control can be performed according to each charge state.

Further, the reference voltage is the higher reference voltage value of the higher one when the electric load is a light load when the battery is in a relatively good charging state, that is, the intermediate charging state, and the charging of the battery is given the highest priority. When the electric load is a heavy load, the charging of the battery is not taken into consideration, and the low reference voltage value is set so that the power transmission to the heavy load is given the highest priority. Therefore, it is possible to optimally charge the battery while appropriately controlling the power supply to the electric load.

〔Example〕

Next, a first embodiment will be described with reference to FIGS. 2 and 3.

In FIG. 2, 1 is a headlight, a promotor,
An electric load such as a defogger, 2 a battery, 3 a vehicle charging generator driven by a vehicle engine (not shown),
Reference numeral 4 denotes a voltage adjusting device, which detects the battery voltage, the battery liquid temperature, the charging state of the battery, the electric load state, etc., and controls the output voltage of the charging generator 3.

Reference numeral 5 denotes a battery charge state detecting means sensor corresponding to the charge state detecting means m ₁ , and the charge state of the battery 2 is estimated by estimating the remaining capacity from the specific gravity of the battery liquid, the charge / discharge current balance, and the battery terminal voltage with respect to the discharge current. Is to detect. 6 is the temperature of the battery 2 (for example, liquid temperature, battery case,
It is a battery fluid temperature sensor that detects the temperature of electrodes etc.)
It constitutes the temperature correction means m ₅ .

The charging generator 3 is composed of an armature winding 31, a full-wave rectifier 32 and a field winding 33 provided on the output side thereof. The current of the field winding 33 is proportional to the conductivity of the transistor 415 forming the switching means m ₆ for turning on / off the field winding current, which will be described later. A generated voltage according to the current is generated, and this voltage is supplied to the battery 2 and the electric load 1 after being rectified by the full-wave rectifier 32.

Next, the structure of the voltage regulator main body 4 will be described. 415 is a switching means for turning on / off the field winding current m ₆
Is controlled by the output of the comparator 414 that compares the adjustment voltage of the voltage adjustment device body 4 with the battery sensing voltage (charging voltage) Vs. That is, it turns on when the sensing voltage Vs is lower than the adjustment voltage, and turns off when it is high. Reference numeral 404 is a detection means for detecting, for example, the conductivity as one of the values correlated with the electric load state of the vehicle.
those forming the m _3, and detects the conduction rate of the transistor 415,
When the conductivity is larger than the first set value, it is a "1" level signal, and when it is smaller than the second set value smaller than the first set value, it is a "0" level signal. Therefore, it has a hysteresis characteristic having the first set value and the second set value. 40
2 is a comparator determining the output of the battery state detection sensor 5, the battery liquid temperature of FIG. 3 - Battery charge status - load - the adjustment voltage characteristic diagram, state of charge S ₁
When it is better than (charging shortage), "1" is output.
Reference numeral 403 is an A to D circuit that obtains the logical product of the outputs of the conductivity detection circuit 404 and the comparator 402. Reference numeral 401 is a comparator that determines the output of the battery charge state detection sensor 5, and outputs "1" when the charge state of FIG. 3 is better than S ₂ (substantially full charge state). 405 is an OR circuit, in the FIG. 3, when the battery state of charge S is S ₂ or more, the output becomes "1". Further, this OR circuit 405 has a charge state of S ₁ or more and the conductivity of the transistor 415 is high, that is, the conductivity detection circuit 4
When the output level of 04 is "1", the output becomes "1". The transistor 407 is controlled by the output of the OR circuit 405 via the resistor 406, and when the transistor 407 becomes conductive and non-conductive, the tap voltage VA of the voltage dividing resistors 410 and 411 is set to two different voltage values (constant voltage Vcc: Will have two divided values). On the other hand, the comparator 40
The battery sensing voltage Vs is input to the inverting input side of 4 via a resistor 412 serving as a charging voltage detecting means (m _{7 in} FIG. 1). The tap voltage VA in this case corresponds to the high reference voltage V ₁ and the low reference voltage V ₂ in FIG. In addition,
The reference voltage is corrected as described later and finally becomes the adjusted voltage.

Note that FIG. 3 will be described here. FIG. 3 is a graphical representation of the adjustment voltage determination made by the hard logic circuit in the circuit shown in FIG. In FIG. 3, the X-axis indicates the battery liquid temperature, and the liquid temperature increases in the direction of the arrow, that is, from left to right. This liquid temperature is measured by the battery liquid temperature sensor 6 shown in FIG. The Z-axis indicates the battery charge state, which is detected by the battery charge state detection sensor 5 in FIG. 2 until S ₁ is the insufficient charge state, S _{1 to} S ₂ are the intermediate charge state, and S _{2 and} above are the full charge state. When the values of the X-axis and the Z-axis, that is, the battery liquid temperature and the battery charge state are determined, the adjustment voltage appears in a graph just above the point where the values of the X-axis and the Z-axis intersect. There is.

That is, the adjustment voltage is a value on the Y-axis and has a complicated box-shaped numerical value distribution that changes depending on both the battery liquid temperature and the battery charge state.

As is apparent from the above circuit configuration, the tap voltage VA becomes a low value such as V _{2 in} FIG. 3 when the transistor 407 is conductive,
When shut off, a higher reference voltage V ₁ will be set. The high and low reference voltages V ₁ and V ₂ are determined by appropriately selecting the voltage dividing resistors 410 and 411 in FIG. As described above, the high reference voltage V ₁ has a bad influence on the power supply to the electric load 1 and the battery charging because the battery 2 is in the insufficient charging state (region up to S _{1 in} FIG. 3). It is set to a high voltage value that does not exceed On the other hand, since the low reference voltage V ₂ is when the battery is in a substantially fully charged state (the region of S ₂ or more in FIG. 3), the battery 2 is near the open terminal voltage, that is, the electric load is output from the generator 3. The voltage value is set to such a low value that the discharge current (current flowing into the electric load 1) from the battery 2 does not increase when the wire is connected to both ends of the battery 2. Reference numeral 408 in FIG. 2 is a temperature compensating circuit which constitutes the temperature compensating means m _5, which uses the output of the battery liquid temperature sensor 6 and the output of the logical OR circuit 405 as input signals to give the tap voltage VA a temperature characteristic and thereby increase or decrease the temperature. Reference voltage (V ₁ , V ₂ )
The correction of the battery liquid temperature and the magnitude of the electric load is performed by using the circuit disclosed in Japanese Patent Laid-Open No. 55-13629.

The operation of the first embodiment having the above configuration will be described below. When the key switch S is turned on and the vehicle engine is driven,
The field winding 3 of the generator 3 rotates. At this time, if the sensing voltage Vs is lower than the adjustment voltage value of the voltage adjusting device 4 (the voltage value applied to the non-inverting input side of the comparator 414), the transistor 415 becomes conductive and the field winding 33 is energized. ,
The generator 3 promptly starts power generation to charge the battery 2, and at the same time, if the electric load 1 is connected, it also supplies power to the load. When the sensing voltage Vs reaches the adjusted voltage value or more during the charging, the transistor 415 is cut off and the generator 3 suppresses power generation. The above-described operation is repeated to control the power generation amount of the generator 3 so that the sensing voltage Vs, that is, the battery terminal voltage, matches the adjusted voltage.

Next, the method for determining the adjusted voltage value that is the set voltage for the constant voltage control will be described in more detail. As shown in FIG. 3, the adjustment voltage is determined in consideration of the battery liquid temperature, the battery charge state and the electric load state. In the above-described first embodiment, the battery charge state is changed to the insufficient charge state (S <S ₁ ),
It is divided into three stages of relatively good intermediate charge state (S ₁ <S <S ₂ ) and full charge state (S <S ₂ ). Then, the electrical load state is detected by the conductivity detection circuit 404, and when the electrical load is large, the regulated voltage is determined to the value shown by the broken line in FIG. 3 and the region related to (S ₁ to S ₂ ) is downgraded. When the electric load is small, a higher adjustment voltage is determined as shown by the solid line in FIG. That is, when S ₁ <S <S ₂ in which the battery charge state is relatively good and when the electric load is small, the adjustment voltage is set to a high value for charging the battery 2. Similarly, when S ₁ <S <S ₂ , when the electric load is heavy, conversely, the charging of the battery 2 is not taken into consideration, and the purpose is to supply power to the electric load 1 in the heavy load state. The adjustment voltage is set to a low value. For the purpose of charging the battery 2, for example, the above-mentioned high and low regulated voltage values have a higher charging capacity if the regulated voltage is set as high as possible. Therefore, the maximum regulated voltage value V _{1 in} FIG. The value is determined in consideration of the relationship between the load, for example, the applied voltage of the lamp load and the life, etc., and is determined by the thermal escape limit of the battery of the slope (B). Further, the minimum adjustment voltage value (C) corrected with respect to the battery liquid temperature is the adjustment voltage required for charging, which is obtained by taking into consideration the influence of the ambient temperature of the battery 2 as well as the above-mentioned heat escape. Is the minimum guaranteed value of. Then, the adjustment voltage V ₂ for the purpose of supplying power to the electric load 1 is determined by the adjustment voltage V ₂
If V ₂ is set higher, the input torque of the generator 3 may increase to deteriorate the fuel consumption and may accelerate the deterioration of the electric load 1. Therefore, a value that does not cause a large discharge current from the battery 2 That is, it may be set to about the battery open terminal voltage. Next, the liquid temperature of the battery 2 is detected by the battery liquid temperature sensor 6 in FIG. 2 and the temperature correction circuit 408 detects a temperature gradient (B) in which the battery 2 does not generate heat escape when the adjustment voltage is V _1. Set the adjustment voltage to hold.
On the other hand, in the case of the regulated voltage V ₂ , the regulated voltage is set so as to have the temperature gradient (B ′) of the open terminal voltage of the battery 2.

Next, a second embodiment in which the voltage regulator 4 according to the present invention is controlled by a microcomputer will be described with reference to FIG. 3 and FIGS. 4 and 5.

FIG. 4 is an overall configuration diagram of a vehicle charging and power generation system including a microcomputer-based voltage regulator 4 of the present invention. Reference numeral 404 constitutes a load state detecting means m ₃ , which detects an electric load state and sets a load mode corresponding thereto. (Hereinafter referred to as load mode sensor).

This load mode sensor 404 detects, for example, the conductivity of the switching transistor 415 forming the switching means m _{6 in} FIG. 1 and has a first load mode signal I ₁ above a certain conductivity, or a second load mode signal I ₁ below that. It is one that generates ₂ . Reference numeral 5 denotes a battery charge state detection sensor that detects the specific gravity of the battery electrolyte solution that correlates with the charge state of the battery 2 and the charge / discharge current ratio to generate the battery charge mode signal S. It is an eggplant. This charge state detection sensor 5 has three charge modes set in this embodiment. That is, the first charge mode signal S _A is in the insufficient charge state (the region of S <S _{1 in} FIG. 3), and the first charge mode signal S _{A is} the relatively good intermediate charge state (S ₁ <S <S _{2 in} FIG. 3). The second charging mode signal S _B and the third charging mode signal S _C are generated when the battery is fully charged (S> S ₂ ). Reference numeral 6 denotes a battery temperature sensor that detects a battery temperature of a battery electrolyte solution or the like related to the charging characteristics of the battery 2 and generates a liquid temperature signal T.
The temperature compensating means constitutes a part of the temperature compensating means shown in the figure, and is constituted by disposing a temperature sensitive element such as a temperature sensitive transistor or a thermistor in the battery electrolyte. A battery voltage detection sensor 7 detects a terminal voltage of the battery 2 and generates a terminal voltage signal V, which constitutes a charging voltage detection means m ₇ .

Reference numeral 8 denotes an A / D conversion circuit, which sequentially converts the analog signals of the battery temperature sensor 6 and the battery voltage detection sensor 7 into digital signals and outputs them to the microcomputer 9. The microcomputer 9 is a one-chip microcomputer that executes arithmetic processing according to a program to be described later based on the output signals from the above-mentioned sensors, and is supplied with operating power from a battery 2 by a constant voltage circuit (not shown). , According to each sensor 5, 6, 7, 404,
It is for controlling the operation of the transistor 415 for controlling the field.

The main program of the microcomputer 9 is executed by a timer interrupt program for every certain fixed period. The main program will be described with reference to the program flowchart of FIG. When the key switch S is turned on, operating power is supplied from a constant voltage circuit (not shown) and the microcomputer 9 is put into an operating state. Then, the control program calculation is started from the start step 101 by the timer interrupt signal, and the process proceeds to the signal input step 102. In step 102, the battery charge state detection sensor 5 receives the battery charge mode signals S _A , S _B and S _C , the battery temperature sensor 6 receives the battery liquid temperature signal T, and the battery voltage detection sensor 7 receives the battery terminal voltage signal V sequentially. Then, the data is temporarily stored in the RAM of the microcomputer 9, and the process proceeds to the charge state determination step 103. In the determination step 103, it is first determined whether or not the battery charge mode signal input and stored in the signal input step 102 is in the fully charged state (the region of S ≧ S _{2 in} FIG. 3), and when S ≧ S ₂ is determined. YES, the process proceeds to step 108, in step 108, the lower third view of the zone from the adjustment voltage corresponding to the battery fluid temperature signal T which has been temporarily stored in step 102 relative to the voltage V ₂ of Is read out from a predetermined map. On the other hand, if it is determined in step 103 that the state of full charge (S ≧ S ₂ ) is not satisfied, the determination result is NO and the process proceeds to the next determination step 104. Then, S ≦ S ₁ in to 104, that is, when it is determined that the insufficiently charged state, the process proceeds to YES, step 107, from the zone of the third view taken herein as the higher reference voltage V ₁ of the still step 102 The liquid temperature-corrected adjustment voltage corresponding to the battery liquid temperature signal T stored in step 1 is read from the map.
The determination of NO in step 104 is made when the battery charge state is S ₂ >S> S ₁ , that is, in the intermediate charge state.
At this time, the process proceeds to step 105 and proceeds to the step of determining whether or not the load mode signal (I ₁ or I ₂ ) from the electric load mode sensor 404 is a predetermined reference value I ₀ or more, I ₀
If it is above, as in the case of proceeding from step 103 to step 108, the adjustment voltage corresponding to the liquid temperature signal T is read from the map from the zone with the lower adjustment voltage V ₂ as the reference.
On the other hand, when the determination is NO at I ₀ or less, the adjustment voltage for the liquid temperature signal T is mapped from the zone based on the higher adjustment voltage V ₁ as in the case of proceeding from step 104 to step 107. The process to read from is executed. Next, the above regulated voltage (Vreg) is compared with the battery terminal voltage signal V, and if it is determined that V ≧ Vreg, the routine proceeds to step 110, where the switching transistor 415 is made non-conductive, and when V ≦ Vreg. Is judged NO, the process proceeds to step 111 for turning on the transistor 415, and the main program execution cycle from the start step 101 to the end step 112 is completed. Therefore, while the key switch 5 is turned on, the above-mentioned timer interrupt program repeats the routine steps 101 to 112 of the main program.
Also in the second embodiment, as in the first embodiment,
It is possible to achieve optimum charging of the battery and optimization of the power generation amount of the generator while appropriately controlling the power supply to the electric load while appropriately monitoring the battery charge state. As a result, it is of course possible to improve the fuel efficiency of the vehicle and the life of the electric load, but it is also possible to achieve highly accurate control characteristics peculiar to the microcomputer control.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing the configuration of the present invention, FIG. 2 is an electric circuit diagram showing a first embodiment of the device of the present invention, and FIG. 3 is a battery fluid temperature-charge state-negative value-in the first embodiment. FIG. 4 is a characteristic diagram showing the relationship with the adjustment voltage, FIG. 4 is a hardware configuration diagram of a system using a computer according to the second embodiment of the present invention, and FIG. 5 is a program for operating the computer shown in FIG. It is a flowchart. DESCRIPTION OF SYMBOLS 1 ... Electric load, 2 ... Battery, 3 ... Vehicle charging generator, m ₁ ... Charge state detecting means, m ₂ ... Reference voltage setting means, m ₃ ... Load state detecting means, m ₄ ... Reference voltage changing means, m ₅ ... Temperature correction means,
m ₆ ... switching means.

Claims (1)

[Claims] 1. A voltage adjusting device for controlling a generated voltage of a vehicle charging generator to charge an in-vehicle battery, comprising: a charging voltage detecting means for detecting a charging voltage of the battery; And a charge state detecting means for detecting as one of at least three charge states of a full charge state and an intermediate charge state, and a state of an electric load connected to the vehicle charging generator is detected, and the state of the load is determined to be heavy. Whether the load state is a light load state or a light load state, a load state detecting means for detecting at least two load states, and a charge insufficient state when the charge state detecting means detects each level of a charge insufficient state or a full charge state. In this case, the reference voltage setting means for setting the reference voltage to the high reference voltage and the reference voltage to the low reference voltage in the fully charged state, respectively, When the load state detected by the load state detection means is a heavy load, the low reference voltage is set to a reference voltage, and when the load state is a light load, the high reference voltage is set to A vehicle charging generator comprising: a reference voltage changing unit that sets a reference voltage; and a switching unit that compares the reference voltage with the charging voltage of the battery to intermittently control the field winding current of the vehicle charging generator. Voltage regulator.