JPS6111537B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This description relates to a storage battery charge/discharge control device, and particularly to a charge/discharge control method for a storage battery mounted on an artificial satellite.

Figure 1 is a block wiring diagram showing an example of a conventional charge/discharge control device for a storage battery mounted on a satellite. In the figure, 1 is a solar cell, 2 is a load on the satellite, 3 is a regulator, 4 is a storage battery, and 5 is a Latching relay, R ₁ and R ₂ are each resistance,
CR ₁ and CR ₂ are diodes for preventing backflow. Further, 6 is a monitor circuit that monitors the temperature of the storage battery 4 and its terminal voltage, 7 and 8 are relay drive circuits, 9 and 10 are monostable multivibrators, and 11 is a comparison circuit.
1 compares the reference voltage, for example, the breakdown voltage of a Zener diode, and the voltage obtained by dividing the voltage input from the solar cell 1 via CR ₁ , and when the voltage of the solar cell 1 becomes less than a predetermined value, the logic becomes "1". Outputs the signal. 12 is a waveform shaping circuit. Further, in FIG. 1, A represents a command signal from the ground that instructs full charging of the storage battery, and B represents a command signal from the ground that instructs trickle charging.

FIG. 2 is an operation time chart showing the operation of each part of the circuit of FIG. 1, and the operation of the circuit of FIG. 1 will be explained with reference to FIG. In FIG. 1, if the temperature of the storage battery 4 and the terminal voltage thereof change from respective predetermined levels as shown in FIG. Change. The signal 101 passes through the waveform shaping circuit 12 and becomes the signal 102 (in the embodiment shown in FIG. 1, the signals 101 and 102 have the same waveform as shown in FIG. 2), which is input to the monostable multivibrator 10. The multivibrator 10 outputs a signal 103 that continues for a predetermined time from the rising point of the signal 102. FIG. 2 shows the waveform of signal 103. The signal 103 energizes the relay drive circuit and connects the latching relay 5 to the contact R side. In this state, the power generated by the solar cell 1 charges the storage battery 4 through the resistor _R2 , resulting in a so-called trickle charge mode. That is, when the temperature of the storage battery 4 is high or the terminal voltage is high, trickle charging is performed. On the other hand, when the temperature and terminal voltage of the storage battery 4 fall below a predetermined level, the falling point of the output signal 101 of the monitor circuit 6 is detected by the waveform shaping circuit 12 as shown as a signal 104 in FIG. is input to the monostable multivibrator 9, which outputs a signal 105 that starts from the signal 104 and continues for a predetermined time, energizes the relay drive circuit 7, connects the latching relay 5 to the contact S side, and shorts the resistor _R2 . .
In this state, the power generated by the solar cell 1 charges the storage battery 4 through the contact S of the latching relay 5, resulting in a so-called full charging mode.

In addition, independently of the control of the charging mode described above, when the voltage of the solar cell 1 drops below a predetermined lower limit level, the comparator circuit 11 outputs a signal with a waveform as shown in the signal 106 in FIG. 2, and performs waveform shaping. A signal having a waveform shown as signal 107 in FIG. 2 is input to the circuit 12, and at its rising point, the monostable multivibrator 9 is triggered, and from that point on, a signal 105 that continues for a predetermined time is output, and the relay is activated. The drive circuit 7 is energized, the latching relay 5 is connected to the contact S side, and the resistor R ₂ is short-circuited. In this state, current is passed from the storage battery 4 to the load 2 through the contact S of the latching relay 5, and the shortage of power generated by the solar cell 1 is supplied from the storage battery 4. That is, the storage battery 4 is in full discharge mode. In this way, the conventional device performs full charge control of the storage battery 4 when the storage battery temperature and storage battery terminal voltage drop below a predetermined lower limit level, and controls the full charge of the storage battery 4 when the voltage of the solar cell 1 drops below a predetermined lower limit level. Full discharge control is performed independently of each other, so when the temperature of the storage battery or its terminal voltage exceeds a predetermined level, trickle charge mode is required, and control to connect the contact of latching relay 5 to the R side and solar When the voltage of the battery 1 drops below a predetermined lower limit level, a full discharge mode is required, which may conflict with the control to connect the contact of the latching relay 5 to the S side.

An example of this conflict will be explained with reference to FIG. At time _t0 , shown on the horizontal axis in Figure 2, the storage battery temperature rises above a predetermined level and the switch is made from full charging to trickle charging, and at time _t1 , torque charging is in progress.
At time t ₂ , the voltage of solar cell 1 drops below the predetermined lower limit level, and after a short delay time, signal 10 is generated at time t ₃ .
5 outputs resistance R ₂ by latching relay 5.
is shorted and enters full discharge mode. When the voltage of the solar cell 1 is restored in this state, power to the load 2 is supplied from the solar cell, and the storage battery 4 is fully charged via the contact S of the latching relay 5, and the temperature of the storage battery 3 continues to rise. , the signal 101 does not change, so the relay drive circuit 8 is not energized, causing serious damage to the storage battery 4.

The present invention aims to eliminate the above-mentioned drawbacks in conventional devices, and for this purpose, the present invention provides control and monitoring of the full discharge mode of the storage battery when the voltage of the solar cell falls below a predetermined lower limit level. The control of the storage battery is controlled by giving priority to the control of the charging mode in response to the output signal of the monitor circuit over the control of the discharge mode of the storage battery, without conflicting with the control of the charging mode of the storage battery in response to the output signal of the circuit. Full charging is performed only when the temperature of the storage battery and the terminal voltage are within predetermined levels, and one embodiment of the present invention will be described below.

FIG. 3 is a block diagram showing an embodiment of the present invention. In the figure, the same reference numerals as in FIG. 1 indicate the same or corresponding parts, and since the operations thereof are also the same, redundant explanation will be omitted. In Figure 3, 13 is the first
Corresponds to the waveform shaping circuit 12 shown in the figure, and only when the signal 101 is not present, the signal 106 is transferred to the AND gate 1 by the inverter 14 and the AND gate 15.
5 and controls the monostable multivibrator 9 as a signal 108. FIG. 4 is an operation time chart showing the operation of each part of the circuit in FIG.
Referring to FIG. 4, the first explanation of the operation of the circuit in FIG.
Points that differ from the operation of the circuit shown in the figure will be explained. However, in FIG. 4, the same symbols as in FIG. 2 indicate the same or equivalent waveforms or equivalent operations. Furthermore, for the purpose of explaining the present invention, the signal 106 that is the output of the comparison circuit 11 will be temporarily referred to as a first control signal, and the signal 101 that is the output of the monitor circuit 6 will be temporarily referred to as a second control signal. A signal 102 or a signal 104 is generated in accordance with the second control signal, and the relay drive circuit 8 uses the signal 102 as a signal 103 to latching the latching relay 5.
is connected to the contact R side, and the signal 104 to signal 105 is
This is the same as in the case of FIG. 1, in which the latching relay 5 is connected to the contact S side by the relay drive circuit 7 and switching between full charging and trickle charging is performed.

The first control signal, the signal 106, passes through the gate 15 and becomes the signal 108 only in the absence of the second control signal to the monostable multivibrator 9.
A signal 105 is generated, and the relay drive circuit 7 connects the latching relay 5 to the contact S side.
Therefore, when the second control signal, that is, the signal 101 is at logic "0", the latching relay 5 closes the contact S.
When the battery is fully charged and the signal 101 becomes logic "1" at time _t0 in Figure 4, the signal 103 is generated and the latching relay 5 is connected to the contact R side to perform trickle charging. However, in this state, at time _t2 , the voltage of the solar cell falls below the predetermined lower limit level, and even if the signal 106 becomes logic "1" as shown in FIG. 4, this signal is blocked by the gate 15, so the signal 108 is kept at logic ``0'' and the latching relay 5 is not connected to the contact S side, so that a failure of the storage battery 4 as explained in the previous section with respect to the circuit of FIG. 1 will not occur.

The above explanation has been about an example in which the present invention is applied to charge/discharge control of a storage battery mounted on an artificial satellite. However, this invention is applicable not only to storage batteries mounted on an artificial satellite, but also to DC Needless to say, the present invention can be used as a charge/discharge control device for a storage battery that supplies current to a load in parallel with the DC power supply when the voltage of the DC power supply drops after being charged by the power supply. Further, in the embodiment of FIG. 3, the first signal 106 and the second signal 10
Although a specific circuit is used for the signal processing circuit from 1 to 1 to generate the signal to energize the relay drive circuits 7 and 8, the circuit is not limited to the specific circuit shown in this embodiment, and any known circuit may be used. It is obvious that a similar signal processing circuit may be used, and in the embodiment shown in FIG. 3, the temperature and terminal voltage of the storage battery 4 are monitored as the second signal 101, and the logical sum of However, the method of creating the second signal is not limited to this embodiment, but it outputs various measured values representing the state of the storage battery 4, performs appropriate data processing from these measured values, and generates a single signal. or a plurality of second signals may be formed. For example, the signal input to the inverter 14 in FIG.
Of 01, only a signal indicating whether the temperature of the storage battery 4 is above a predetermined level or below a predetermined level may be used.

As described above, according to the present invention, charging and discharging control can be performed to prevent abnormal temperature rise of the storage battery.

[Brief explanation of drawings]

Fig. 1 is a block wiring diagram showing an example of a conventional charge/discharge control device for a storage battery mounted on an artificial satellite, Fig. 2 is an operation time chart showing the operation of each part of the circuit in Fig. 1, and Fig. 3 is an invention according to the present invention. FIG. 4 is a block diagram showing one embodiment of the present invention, and FIG. 4 is an operation time chart showing the operation of each part of the circuit of FIG. In the figure, 1 is a solar cell, 2 is a load, 3 is a regulator, 4 is a storage battery, 5 is a latching relay,
6 is a monitor circuit, 7 and 8 are each a relay drive circuit, 9 and 10 are each a monostable multivibrator, 11 is a comparison circuit, 13 is a waveform shaping circuit, and 14
is an inverter, and 15 is an AND gate. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A series connection circuit of a DC power supply device and a reverse current prevention diode in which voltage changes occur, a load connected in parallel to this series connection circuit, a storage battery and a diode connected in series to this storage battery with the polarity in the discharge direction of the storage battery. a storage battery discharging circuit in which a series circuit of is connected in parallel with the load; a current limiting resistor connected in parallel with the diode to limit the storage battery charging current;
a comparison circuit that compares the output voltage of the DC power supply with a predetermined reference voltage and outputs a first control signal when the output voltage is below a predetermined value; A monitor circuit that outputs a second control signal when a predetermined temperature is exceeded, and short-circuits the current limiting resistor by generating the first control signal when the second control signal is not present. 1st
A charge/discharge control device for a storage battery, comprising a second control circuit that opens or shorts the current limiting resistor in response to the second control signal.