JPS6259531B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a battery charging device with a plurality of charging branches for charging individual batteries individually.

In this type of device, when the charging branch that is being powered exhibits an abnormal voltage, such as when the battery that is being charged is a short-circuited battery that has an internal short circuit, or when the battery is not properly installed in the charging branch that is being powered. In order to shorten the overall charging time, it is preferable to quickly sense such an abnormal state, stop power supply to this charging branch, and start supplying power to the next charging branch. In addition, since adjacent charging branches may both exhibit abnormal voltages when switching power supply, the detection means may output a detection signal due to the abnormal voltage even if the battery is normal and correctly installed in the charging branch. Charging then shifts to the next charging branch. Therefore, there is a problem that the battery is not charged even though it is a normal battery. Therefore, it is desirable that the detection means once reset to a state in which there is no detection signal when switching the power supply, and then detects the abnormal voltage of the charging branch again.

The present invention has been invented in view of these points, and one specific example of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram of a device according to the invention.
In this drawing, reference numeral 1 denotes a charging power source, to which a plurality of charging branches 3 ₁ to 3 _o for individually charging individual batteries 2 ₁ to 2 _o are connected in parallel. Each charging branch is provided with battery connection terminals 4, 4' and switch circuits ₅₁ to _5o , and each switch circuit is configured such that only one switch circuit is sequentially closed by the output of the automatic switching circuit 6. Opening/closing controlled. A resistive voltage divider circuit 8 is provided between the common charging path 7 of each charging branch and ground.

Reference numeral 9 denotes a detection circuit for detecting a predetermined state of charge of the battery being charged, to which the output of the voltage dividing circuit 8 corresponding to the charging voltage of the battery is applied. Reference numeral 10 denotes a detection circuit that detects an abnormally high voltage in the charging branch that is being supplied with power, and 11 is a sensing circuit that detects an abnormally low voltage in the charging branch that is being supplied with power. The output of the voltage divider circuit 8 is applied, which corresponds to the voltage of the charging branch during power supply. Reference numeral 12 denotes a pulse generation circuit, which generates a single pulse based on the outputs of the detection, sensing and sensing circuits 9, 10 and 11.
Reference numeral 13 designates a reset circuit that generates a reset signal upon receiving the initial output _Q0 of the single pulse or automatic switching circuit 6, and uses the reset signal to trigger the detection circuit 9.
and reset the detection circuit 10.

The automatic switching circuit 6 is composed of a _binary ring counter, and when the charging power source 1 is turned on, the initial output is
Q ₀ is generated, and upon arrival of the start signal from the start switch circuit 15, the initial output Q ₀ is switched to the next output Q _1. From then on, each time the single pulse arrives, the output changes from Q ₂ to Q _2o-1. , and then sequentially switches to Q ₀ .

The operation of the above configuration will be explained based on the waveform diagram in FIG. 2. FIG. 2 is a voltage waveform diagram of each part in FIG. 1, where A is the voltage applied to the resistive voltage divider circuit 8, B is the charging voltage of the batteries ₂₁ to _2o , and C is the output voltage of the automatic switching circuit 6. , D is the output voltage of the detection circuit 9, E is the output voltage of the detection circuit 10, F is the output voltage of the sensing circuit 11, G is the single pulse voltage of the pulse generation circuit 12, and H is the reset signal from the reset circuit 13. FIG.

Now, when charging power source 1 is turned on at time _t0 , automatic switching circuit 6 produces an initial output _Q0 , and this initial output causes reset output of reset circuit 13 to be activated.
h ₀ appears, and this reset output causes the detection circuit 9
and the detection circuit 10 has been reset. In addition, since the initial output Q ₀ does not close any of the switch circuits 5 ₁ to 5 _o of the charging branches 3 ₁ to 3 _o , the open circuit voltage of the common charging path 7 is applied to the resistive voltage divider circuit 8, and this Since the open circuit voltage is higher than the voltage when the battery is charged, the sensing circuit 11 produces no output. This state is maintained until the start signal from the start switch circuit 15 arrives.

At time _t1 , when the start signal from the start switch circuit 15 arrives at the automatic switching circuit 6, the output of the automatic switching circuit 6 is switched from the initial output _Q0 to the next output _Q1 . This output Q ₁ closes the switch circuit 5 ₁ of the first charging branch 3 ₁ and starts charging the first battery 2 ₁ . Furthermore, at time _t1 , the reset output _h0 disappears, so the detection circuit 9 and the detection circuit 10 begin to operate.

At time _t2 , the detection circuit 9 detects a predetermined charging voltage as a predetermined charging state of the first battery ₂₁ and generates a detection output _d1 . A single pulse g ₁ is generated from the pulse generation circuit 12 based on this detection output d ₁ . This single pulse _g1 causes the output of the automatic switching circuit 6 to
The state changes from Q ₁ to Q ₂ , the first switch circuit ₅₁ is opened, and charging of the first battery ₂₁ is completed. Also, a reset output _h1 is generated from the reset circuit 13 based on this single pulse _g1 . The detection circuit 9 and the detection circuit 10 are reset by this reset output _h1 . Since the output Q ₂ of the automatic switching circuit 6 does not close any of the switch circuits 5 ₁ to 5 _o , the common charging path 7 becomes an open circuit voltage. On the other hand, the period W of the reset output h ₁ is the period of the single pulse g ₁ , and at the end of this period t ₃ , the reset detection circuit detects that the open circuit voltage of the common charging path 7 is equal to the reference voltage of the detection circuit. It is detected via the resistive voltage divider circuit 8 that the voltage is larger than V _T , and a detection output e ₁ is generated. This detection output generates a single pulse g ₂ from the pulse generation circuit 12 again.
appears, and based on this single pulse, the output of the automatic switching circuit 6 switches from Q ₂ to Q ₃ , which closes the switch circuit 5 ₂ of the second charging branch 3 ₂ and connects the second battery. 2 Charging of ₂ starts. In addition, a reset signal is generated from the reset circuit 13 by a single pulse _g2 .
h ₂ appears, and the detection circuit 9 is activated for the reset signal period W.
and reset the detection circuit 10. Therefore, both circuits 9 and 10 start operating after the period of the reset signal _h2 ends, but since the reset signal period W with respect to the charging period of the battery ₂₂ is short, the reset signal period W during the charging period is It has no effect on operation. At time _t4 , the detection circuit 9 detects the predetermined state of charge of the second battery ₂₂ and outputs a detection output.
d ₂ is generated, and charging of the second battery ₂₂ is completed in the same manner as described above.

If all the third to n-th batteries are normal batteries and are correctly connected to the connection terminals 4, 4', then the n-th battery 2 _o will be sequentially charged in the same way, and at time t ₂
When _the predetermined state of charge of the n-th battery 2 _o is detected by the detection circuit 9 at o, and the detection output d _o is generated, the output of the automatic switching circuit 6 is switched to the initial output Q ₀ by a single pulse g _{2 o-1.} , and a reset signal h _{2o- 1} resets the detection circuit 9 and the detection circuit 10 based on the single pulse g 2o-1. After the disappearance of this single pulse g _2o-1 , the reset signal h ₀ is continuously generated by the initial output Q ₀ .

Therefore, if the m-th and (m+ ₁₎ th batteries 2m, 2n ₊₁ are short-circuited batteries with an internal short circuit, the 1st to (m- ₁₎ th batteries will be charged normally, as described above. . The detection output d n-1 appearing at the end of charging time t _{2n-2 of} the m- ₁ battery 2 n- ₁ generates a single pulse g _2n-2 and a reset signal h _2n-2 to activate the automatic switching circuit 6. The output is switched from Q _2n-3 to Q _2n-2 , and the detection circuit 9 and the detection circuit 10 are reset during the period W of the reset signal h _2n-2 . Also, that period W
The detection circuit 10 detects the open-circuit voltage of the common charging path 7 at the time t _2n-1 when t 2n-1 ends, producing a detection output e _n-1 , and the single pulse g _2n-1 changes the output of the automatic switching circuit 6 to Q _{2n -2} to Q _2n-1 , and charging of the m-th battery 2 _n starts from time t _2n-1 . Since this m-th battery is a short-circuited battery, its battery terminal voltage is lower than the reference voltage V _S of the sensing circuit 11, so the sensing circuit 11 senses this state at the end time t _2n of the reset signal h _2n-1. produces a sensed output f ₁ . That is,
Since no single pulse is generated in the pulse generating circuit 12 until the end of the single pulse g _2n-1 , the sensing output f ₁ is produced at the end time t _2n . A single pulse g _2n is generated based on this sensing output f ₁ , and the output of the automatic switching circuit 6 is switched to Q _2n to stop charging the m-th battery 2 _n , and a reset signal h _2n causes the detection circuit 9
and reset the detection circuit 10. single pulse g
Until the end point t _2n+1 of _2n , the output Q _2n of the automatic switching circuit 6 does not close any of the switch circuits 5 ₁ to 5 _o , so the common charging path 7 exhibits a high open circuit voltage.
The sensing circuit 11 is reset by this open circuit voltage. The detection circuit 10 detects this open circuit voltage at time t _2n+1 and produces a detection output e _n , and the output of the automatic switching circuit 6 changes to Q _2n by a single pulse g _2n+1.
to Q _2n+1 , and the next m+1 battery 2 _n+
Start charging ₁ .

However, since this (m+ ₁₎ th battery is also a short-circuited battery, the next single pulse will not occur until the end of the period of the single pulse g _2n+1 , so the reset signal h _2n+1
At the end time t2n ₊₂ , the sensing circuit 11 again senses that the battery is shorted and produces a sensing output _f2 , and stops charging the m+ ₁ battery as in the case of the m-th battery _2n . , the next battery 2 _n+2 is charged.

Next, assuming that the m-th and m+ ₁ -th batteries 2 _n and 2 _n+1 are not connected to the connection terminals 4 and 4' of the charging branches 3 _n and 3 _n+1 , the switching circuit 5 _n is closed. When supplying power to charging branch 3 _n , reset signal h _2n-1
At the time t _2n when , the detection signal e _2n-1 is
Also, charging branch 3 _n by closing switch circuit 5 _n+1
+1 power supply, the detection signal e _{2n+ 1} appears at the time t _2n+2 at which the reset signal h 2n+1 ends, and the generation of the single pulses g _2n , g _2n+2 causes each charging branch to Stop power supply to 3 _n and 3 _n+1 .

In the middle of switching between multiple charging branches,
If the open-circuit voltage of the charging power source 1 does not appear on the common charging path 7, the sensing circuit 11 cannot be reset, and if the sensing circuit 10 is not forcibly reset by the reset signal of the reset circuit 13, The detection circuit cannot be reset. Therefore, if the sensing circuit 11 and the detection circuit 10 are not forcibly reset, when the adjacent charging branches both exhibit abnormal voltages during power supply, 2.
It becomes impossible to detect the second abnormal voltage.
As a result, excessive current continues to flow through the charging device,
Alternatively, a problem arises in that power is not supplied to a charging branch that should be supplied with power after the charging branch that exhibits the second abnormal voltage.

As described above, according to the present invention, there is a detection circuit that detects a predetermined state of charge of a battery being charged, a detection circuit that detects an abnormally high voltage in a charging branch that is currently being supplied with power, and a detection circuit that detects an abnormally low voltage in a charging branch that is currently being supplied with power. generating a single pulse from a pulse generating circuit based on the output of the sensing circuit for sensing; the single pulse activating a reset circuit to reset the detection circuit and the detection circuit; The switching output of the automatic switching circuit switches the power supply to a plurality of charging branches, and the sensing circuit is reset by the open voltage of the charging power supply during the switching of the charging branches, so that charging during power supply is After the branch is powered off, the detection, sensing and sensing circuits can be reset respectively. Therefore, even if adjacent charging branches that are sequentially supplied with power exhibit abnormally low voltage or abnormally high voltage during power supply, such abnormal state can be detected and the power supply of the charging branches can be accurately controlled. can do.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a specific example of the apparatus according to the present invention, and FIG. 2 is a voltage waveform diagram of each part of FIG. 1. 2 ₁ ~ 2 _o ... battery, 3 ₁ ~ 3 _o ... charging branch,
9...detection circuit, 10...detection circuit, 11...sensing circuit, 12...pulse generation circuit, 13...reset circuit.

Claims (1)

[Claims] 1. A plurality of charging branches that individually charge each battery, a detection circuit that detects a predetermined state of charge of the battery being charged, a detection circuit that detects abnormally high voltage in the charging branch that is currently supplying power, and a sensing circuit for sensing an abnormally low voltage in a charging branch of the plurality of charging branches; a pulse generating circuit for generating a single pulse based on the output of the detection, sensing and sensing circuit; In a battery charging device comprising an automatic switching circuit that sequentially switches the power supply through an open period of a charging power source, and a reset circuit that resets the detection and detection circuit according to the single pulse during the period of the single pulse. . A battery charging device, characterized in that the sensing circuit is reset by an open-circuit voltage of a charging power source during switching of the charging branch.