JPH05176470A - Self discharging/supplementary charging method for battery - Google Patents

Abstract

PURPOSE:To realize supplementary charging of a battery causing no overcharge while preventing useless power consumption. CONSTITUTION:The supplementary charging system for charging a battery 4 through a charging resistor 3 comprises a sensor 5 for detecting the ambient temperature of the battery 4 and a function generator 7 receiving an output from the temperature sensor 5 to output a function representing the relationship between the ambient temperature and self discharge current. Output from the function generator 7 is employed as a supplementary charging current command value and the battery 4 is supplementally charged while compensating voltage drop across the charging resistor 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery self-discharge supplement charging method.

[0002]

2. Description of the Related Art FIG. 4 shows a basic battery charging circuit, in which 1 is a power source, SW is a switch SW, 2 is a charger, 3 is a charging resistor, and 4 is a battery. When the charging start switch SW is turned on, charging power is supplied from the power source 1 to the charger 2. The charger 2 rapidly charges the battery 4, and when full charge is detected, trickle charging is performed.

As is well known, if a battery is left (stored) in a charged state, energy is lost due to self-discharge as shown in FIG. After that, it is necessary to continue charging for the amount of self-discharge. Conventionally, this supplemental charging is performed with a current corresponding to the maximum self-discharge amount.

[0004]

However, as shown in FIG. 6, the amount of self-discharge differs depending on the storage temperature (ambient temperature) of the battery, and therefore, in the method of supplement charging with a current corresponding to the maximum amount of self-discharge. However, there is a risk of overcharging, and power will be consumed unnecessarily.

The present invention has been made to solve this problem, and it is an object of the present invention to provide a self-discharge replenishment charging method for a battery, which can prevent wasteful power consumption and can perform replenishment charging without causing overcharging. To aim.

[0006]

In order to achieve the above object, the present invention provides a temperature measuring sensor for detecting the ambient temperature of the battery in claim 1 when the battery is replenished and charged through a charging resistor. It is equipped with a function generator that inputs the output of the temperature sensor and outputs the relationship of the self-discharge current with respect to the ambient temperature as a function.The output of this function generator is used as the supplementary charging current command value to compensate for the voltage drop due to the charging resistor. However, the battery is configured to be replenished and charged.

According to a second aspect of the present invention, the battery is a battery of an engine type generator having a built-in engine starting battery.

[0008]

In the present invention, the amount of current during replenishment charging changes according to the ambient temperature of the battery, and the battery is always replenished and charged with a current commensurate with the amount of self-discharge.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 5 is a temperature measuring sensor for detecting the storage (ambient) temperature T _B of the battery 4, and 6 is a function generator, which receives the output of the temperature measuring sensor 5 and is shown in FIG. The function output i _{d of the} temperature T _B −self-discharge characteristic (current command value having a value equal to the self-discharge current) is output. 7 is a charging resistor 3
A resistance element having the same resistance value as the current command value i _d
To a voltage v _R. 8 is this voltage v _R and battery 4
It is an adder that adds the detected value of the voltage v _B of. A power amplifier 9 supplies power corresponding to the added value [v _R + v _B ] to the battery 4 through the charging resistor 3.

[0011] Thus, in this embodiment, since the value of the current command i _d at topping charge varies according to the ambient temperature T _B, the battery 4 is always supplemented with the magnitude of the current corresponding to the self-discharge amount Since the battery is charged, it is not replenished and charged with a current corresponding to the maximum self-discharge amount as in the conventional case. Therefore, overcharging can be prevented and unnecessary power consumption can be avoided.

FIG. 2 shows an example of the preferred embodiment of the present invention. The figure shows a built-in-battery engine-type power generator, which is a portable type, so that the built-in engine starting battery 41 has a low rating of 12 to 24 volts. In FIG. 2, 10 is a turbine engine EG, 20 is a three-phase permanent magnet type AC generator SG, 31 is a forward conversion circuit having a reverse conversion function, 32 is an electrolytic capacitor CD, 33 reverse conversion circuit, and UO1 and UO2 are AC. Side terminal, 34 reactor Lo, 35 capacitor Co, 36 current limiting resistor, SW2 short-circuit switch, T
O1 and TO2 are device output terminals, and 100 is a general household 10
An outlet for 0 volt, 50 is a control circuit. 31-
Reference numeral 35 constitutes a main circuit.

The forward conversion circuit 31 is constructed by bridge-connecting six transistors QB1 to QB6 having an antiparallel diode DB, and the AC generator SG is an engine EG.
In the power generation operation driven by, the six diodes DB that form the three-phase full-wave rectifier circuit are
It rectifies the phase output and converts it to DC power. Inverse conversion circuit 33
Is a flywheel diode DR1, DR2, DR3, D
A PWM type inverse conversion circuit (single-phase sinusoidal PWM inverter) configured by bridge-connecting transistors Q1 to Q4 each having R4, and receiving a control pulse S2 from an inverse conversion control unit 52 of a control circuit 50. , The above DC power when the AC generator SG is in the power generating operation is converted into single-phase AC power. This single-phase AC power is applied to the AC side terminal U
It is sent from O1 and UO2, smoothed by an LC filter including a reactor 34 and a capacitor 35, and supplied to a load (not shown) via the device output terminals TO1 and TO2. In the battery BATT, the positive electrode side is set to the reactor Lo side between the interconnection point (device output terminal TO2) of the reactor Lo and the capacitor Co forming the LC filter and the negative electrode side (negative electrode N) of the electrolytic capacitor CD. A battery charger 61 inserted through the switch SW1 for charging the battery BATT has a positive electrode P and a battery B.
It is inserted between the ATT and the positive electrode side. The switch SW1 is inserted between the battery BATT and the reactor Lo, and the electric power is taken out from the connection point between the both through the one diode D1 of the matching diode and the electric power from the positive electrode P through the other diode D2. Electric power is supplied to the control circuit power supply unit 62. The power supply unit 62 generates electric power for driving each control unit in the control circuit 50. Reference numeral 63 is a determination unit that inputs the generator operation command RUN ^* and the detection signal of the voltage detector 64 as determination data, and outputs a battery initial charge command BPC ^* and an engine start command ESTRT ^* . FIG. 3 shows a decision matrix built in the decision unit 63. The voltage detector 64 detects the voltage Vdc of the electrolytic capacitor CD. The battery initial charge command BPC ^* is given to the charger control unit 65, and the engine start command ES
TRT ^* is given to the engine start control unit 66. The engine start control unit 66 controls the reverse conversion control units 51 and 52 and the switch SW1.

Incidentally, P and N respectively indicate the positive and negative electrodes of the DC circuit in which the smoothing capacitor CD is inserted.

Next, the operation of this embodiment will be described.

First, the operation of initially charging the battery BATT will be described.

[Initial Charge Mode] In the present embodiment, since the charging power is taken from the outlet 100, when the initial charge is performed, the switch SW2 is opened and the initial charge resistor R is inserted, and the device output terminal TO1, TO2 is connected to this outlet 100. Device output terminal TO1,
When TO2 is connected to this outlet 100, the device output terminal TO1 → initial charging resistance R → diode DR3 → electrolytic capacitor CD → diode DR2 → reactor Lo →
A direct current flows through the path of the device output terminal TO2, the electrolytic capacitor CD is charged, and the capacitor voltage V _dc becomes a predetermined value or more. The control circuit power supply unit 62 takes in the capacitor voltage V _dc through the diode D2, and the control circuit 5
Electric power for driving each control unit within 0 is generated.

The determination unit 63 _{closes the} switch SW2 when the generator operation command RUN ^* is not input and the voltage V _dc of the electrolytic capacitor CD is a predetermined value or more, and the battery initial charge command BPC ^* is issued to the charger control unit. 65, the charger control unit 65 causes the battery charger 61 to start operating. As a result, the battery charger 61 has the device output terminal TO1.
→ diode DR3 → battery charger 61 → battery B
Electric power is taken from the outlet 100 through the ATT path to charge the battery BATT.

The determination matrix of the determination unit 63 is such that, in this initial charging mode, even if the generator operation command RUN ^* is erroneously input to the determination unit 63, the battery initial charging command BPC ^* disappears, and Engine start command EST
It is configured so that RT ^* is not output.

[Engine Start Mode] It is assumed that the generator operation command RUN ^* is given to the determination unit 63 after the initial charging of the battery is completed. The determination unit 63 checks the value of the capacitor voltage Vdc,
When dc is equal to or lower than a predetermined value (0 volt), the engine start command ESTRT ^* is output to the engine start control unit 66. Upon receiving the engine start command ESTRT ^* , the engine start control unit 66 outputs a switch close command for closing the switch SW1 to connect the battery BATT to the main circuit, and turns off Q1, Q3, and Q4 to turn off the transistors. The reverse conversion control unit 52 is supplied with a chopper operation command for causing the Q2 to perform a chopper operation, and the reverse conversion control unit 51 is supplied with a start command for operating the six transistors QB (QB1 to QB6) of the forward conversion circuit 31 as inverters. As a result, the battery BATT is connected to the main circuit, a boost chopper circuit is formed, and a predetermined voltage is applied to the electrolytic capacitor CD. The six transistors QB operate as an inverter using the electrolytic capacitor CD as a power source, convert a DC voltage into a three-phase AC voltage and supply the AC voltage SG to the AC generator SG. As a result, the AC generator SG operates as an electric motor to start the engine EG. When the engine EG reaches a predetermined rotation speed, the engine start command ESTRT ^* , the chopper operation command and the start command disappear, the switch SW1 opens, the battery BATT is disconnected from the main circuit, and the engine EG start mode ends. To do.

[Power Generation Mode] When the starting mode of the engine EG ends, a close command is given to the switch SW2, and the initial charging resistor R is short-circuited. Then, the inverse conversion control unit 52
F The inverter operation command is supplied. As a result, the output of the generator SG converted into DC power by the diode bridge of the forward conversion circuit 31 has a desired frequency by the reverse conversion circuit 33,
The AC power is converted to a desired voltage, smoothed by an LC filter including a reactor 34 and a capacitor 35, and supplied to a load (not shown) via the device output terminals TO1 and TO2.

After the engine starter operation is completed, the battery charger 61 is controlled so as to charge the power lost by the battery in the engine starting mode.

This device has device output terminals TO1 and TO2.
There is a convenience that the initial charging of the battery BATT can be automatically performed only by connecting the battery to the household outlet 100.

This device has the advantage that it can take in charging power from the household outlet 100 and can be easily operated by an unfamiliar person. However, because of its simplicity, the device output terminal TO1 can be used even after full charge. , TO2 is frequently left for a long period of time while being connected to the household outlet 100. Therefore, in the above-mentioned conventional replenishment charging method, the performance of the battery is deteriorated and the liquid leaks due to overcharging, but if the circuit of the present embodiment is incorporated in the charger control unit 65,
Even if the battery is left for a long period of time, it is possible to prevent the performance of the battery from deteriorating and the leakage discharge capacity from decreasing, and avoid unnecessary power consumption.

[0025]

As described above, the present invention changes the amount of current during replenishment charging according to the ambient temperature of the battery, and
Since the battery is replenished and charged with a current corresponding to the amount of self-discharge, there is no unnecessary power consumption, overcharging can be reliably avoided, and troubles can be prevented. It is very suitable to carry out.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the present invention.

FIG. 2 is a circuit diagram showing an example to which the present invention is applied.

FIG. 3 is a diagram showing a determination matrix in the application target.

FIG. 4 is a diagram showing a battery charging circuit.

FIG. 5 is a diagram showing a self-discharge characteristic of a battery.

FIG. 6 is a diagram showing ambient temperature-self-discharge characteristics of a battery.

[Explanation of symbols]

 1 Power Supply 2 Charger 3 Charging Resistance 4 Battery 5 Temperature Measuring Sensor 6 Function Generator 7 Resistance Element 8 Adder 9 Power Amplifier 10 Engine 20 AC Generator 31 Forward Conversion Circuit 32 Smoothing Capacitor 33 Inverse Conversion Circuit 34 Reactor 35 Capacitor 36 current limiting resistor 41, BATT battery 50 control circuit 51, 52 reverse conversion control unit 61, BACH battery charger 62 control power supply unit 63 determination unit 64 voltage detector 65 charger control unit 66 engine start control unit 100 outlet Q1 Q4 transistor QB1 to QB6 transistor D, DB, DR1 to DR4 diode D, DR1 to DR4 diode TO1, TO2 device output terminal

Claims (2)

[Claims] 1. When a battery is replenished and charged through a charging resistor, a temperature sensor for detecting the ambient temperature of the battery and an output of the temperature sensor are input to output a function of a self-discharge current with respect to the ambient temperature as a function. A self-discharge replenishment charging method for a battery, characterized in that the output of the function generator is used as a replenishment charging current command value to replenish the battery while compensating for a voltage drop due to the charging resistance. .. 2. The self-discharge replenishment charging method for a battery according to claim 1, wherein the battery is the battery of an engine type power generator having a built-in engine starting battery.