JP2006108797A - Charging method of battery and base station apparatus utilizing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a charging method of a battery with which the battery is charged while suppressing increase in power to be supplied to a base station apparatus. <P>SOLUTION: A communication section 12 communicates with a terminal of a communication object. Power with a regulated value on the basis of a scheduled power value to be consumed in the communication section 12 is externally supplied to a power supply section 14 via a power socket. A detection section 16 receives a rate of slots to be used for communication with the terminal of the communication object shared in one frame from a baseband processing section 30. The detection section 16 generates a control voltage 200 while changing the voltage level in response to the received rate of the slots and provides an output of the control voltage 200. A charging section 18 generates a charging current from the supplied power while controlling a value of a charging current on the basis of the control voltage 200. The battery 20 is charged by the charging current. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a battery charging technique, and more particularly, to a battery charging method for charging a battery provided in a base station apparatus and a base station apparatus using the same.

Computers equipped with batteries are portable and can be used in places where AC power is not available. On the other hand, if an AC power adapter is connected to a power outlet in a place where AC power can be used, DC power is supplied to the computer. As a result, the supplied power is used to charge the system load and battery inside the computer. Conventionally, as a computer power consumption control technique, the power consumption of the entire computer is within the capacity of the AC power adapter on the assumption that the power consumption of the system load is always the maximum power consumption. Control is executed. However, the actual power consumption of the system load changes according to the operating state of the computer. Therefore, the power corresponding to the difference between the maximum power consumption of the system load and the actual power consumption is not used, and the capacity of the AC power adapter may be wasted (for example, refer to Patent Document 1).
JP 2000-172387 A

  A mobile communication system such as a second generation cordless telephone system includes a base station device and a terminal device. The second generation cordless telephone system is also referred to as a simplified mobile phone system. Since the base station device can be said to be infrastructure equipment, normal operation is required even in the event of a power failure. Furthermore, even if a power outage is about 0.5 seconds, the base station device needs to be restarted, so that the base station device may be suspended for several minutes. Therefore, it is desirable for the base station apparatus to incorporate a battery. When the battery is built in the base station device, if the power consumption setting is based on the maximum power consumption planned for the communication function and the power consumption for battery charging, the planned power consumption is high. turn into. However, the base station apparatus is always supplied with power in cases other than a power outage, and it is preferable that the planned power consumption is low considering the aspect of the apparatus and the cost.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a battery charging method for charging a battery while suppressing an increase in power to be supplied to the base station apparatus, and a base station apparatus using the battery charging method. There is to do.

  In order to solve the above-described problem, a base station apparatus according to an aspect of the present invention has a value defined based on a communication unit that communicates with a communication target terminal device and a value of power that is scheduled to be consumed in the communication unit. Power is supplied from the outside, the communication unit is driven by the supplied power, and a power supply unit that generates a charging current from the supplied power, and is charged by the charging current generated in the power supply unit, and power from the outside When the supply of power is stopped, the value of the charging current generated by the power supply unit is controlled based on the battery that supplies power for driving the communication unit and the actual power value consumed in the communication unit A control unit.

  The “value of power scheduled to be consumed in the communication unit” is a value of power prescribed in advance for the communication unit, and is prescribed separately from the value of power when actually used. . On the other hand, the “value of actual power consumed in the communication unit” is a value of power when actually used. The “value of power scheduled to be consumed in the communication unit” has a value larger than the “value of actual power consumed in the communication unit”.

  According to this aspect, the value of the power supplied to the base station apparatus is the value of the actual power consumed in the communication unit while maintaining a value defined based on the value of the power scheduled to be consumed in the communication unit. Since the value of the charging current is controlled according to the value, the battery can be charged while suppressing an increase in power to be supplied to the base station apparatus.

  The communication unit forms a frame including a plurality of slots and uses a predetermined slot included in the frame to execute communication with a terminal device to be communicated. As a value of actual power consumed, a ratio occupied by a slot used for communication with a communication target terminal device in one frame formed by the communication unit may be used. In this case, the value of the actual power consumed in the communication unit can be estimated without measuring the actual power consumption.

  Another aspect of the present invention is a battery charging method. In this method, in a base station device having a communication circuit that communicates with a terminal device to be communicated, power of a value defined based on the value of power scheduled to be consumed in the communication circuit is supplied and supplied from the outside. The communication circuit is driven by the generated power, and the charging current is generated from the supplied power while controlling the charging current value based on the actual power value consumed in the communication circuit. To supply.

  Yet another embodiment of the present invention is also a battery charging method. The method includes a step of communicating with a terminal device to be communicated, and a step of communicating with the supplied power by supplying a power having a value defined based on a power value scheduled to be consumed in the communicating step. And generating a charging current from the supplied power, and charging the battery by the generated charging current and driving the communication step when the external power supply is stopped. And a step of controlling the value of the charging current to be generated based on the value of the actual power consumed in the communicating step.

  The step of communicating forms a frame including a plurality of slots and uses a predetermined slot included in the frame to execute communication with a terminal device to be communicated, and the step of controlling includes communicating As the value of the actual power consumed in the step of performing, the ratio of the slot used for communication with the communication target terminal device in one frame formed by the step of communicating may be used. The controlling step may target a slot used for transmission to the communication target terminal device as a slot used for communication with the communication target terminal device.

  The step of measuring further comprises the step of measuring the value of power consumed in the step of communicating, and the step of controlling uses the value of power measured in the step of measuring as the value of actual power consumed in the step of communicating. May be. In the measuring step, the value of power consumed in the transmission process may be measured as the value of power consumed in the communicating step.

  It should be noted that any combination of the above-described constituent elements and a representation of the present invention converted between a method, an apparatus, a system, etc. are also effective as an aspect of the present invention.

  According to the present invention, the battery can be charged while suppressing an increase in power to be supplied to the base station apparatus.

  Before describing the present invention in detail, an outline will be described. An embodiment of the present invention relates to a base station apparatus in a second generation cordless telephone system. The base station apparatus forms a frame composed of a plurality of slots, and executes communication with the terminal apparatus using the slots. Also, the base station apparatus can communicate with a maximum of three terminal apparatuses per frame, but the number of terminal apparatuses that communicate with each other varies. The base station apparatus according to the present embodiment normally operates by being connected to an external power source and supplied with power from the outside, but has an internal battery so that it can operate even in the event of a power failure. .

  Here, the value of the power supplied from the outside by the base station apparatus is defined based on the value of the power value scheduled in the communication processing in the base station apparatus. However, the value of the actual power used in the communication processing varies depending on the variation in the number of terminal devices communicating with the base station device. Therefore, the base station apparatus increases the value of the charging current for charging the battery if the actual power value decreases, and increases the charging current for charging the battery if the actual power value increases. Control to reduce the value.

  FIG. 1 shows a configuration of a base station apparatus 100 according to an embodiment of the present invention. Base station apparatus 100 includes antenna 10, communication unit 12, power supply unit 14, detection unit 16, charging unit 18, battery 20, and diode D. The communication unit 12 includes a switch 22, a transmission unit 24, a reception unit 26, a modem 28, and a baseband processing unit 30. Further, the control voltage 200 is included as a signal.

  The communication unit 12 communicates with a communication target terminal device (not shown). Here, the communication unit 12 forms a frame including a plurality of slots and uses a predetermined slot included in the frame to execute communication with the terminal device to be communicated. FIG. 2 shows a configuration of a frame format formed in the communication unit 12. The figure corresponds to the frame format in the second generation cordless telephone system. Since the second generation cordless telephone system adopts TDMA / TDD (Time Division Multiple Access / Time Division Duplex), a frame format corresponding to the TDMA / TDD (Time Division Multiple Access / Time Division Duplex) is configured. The frame includes eight slots from “slot 1” to “slot 8”.

  Further, “slot 1” to “slot 4” are used when signals are transmitted from the downlink, that is, the communication unit 12, and “slot 5” to “slot 8” are uplinks, that is, the communication unit 12. Used when receiving signals. Further, one slot corresponding to the uplink and one slot corresponding to the downlink are used for one terminal apparatus. For example, “slot 2” and “slot 6” are used for the first terminal device. Of the plurality of slots, “slot 1” and “slot 5” are used for control signals. The illustrated frame is continuously repeated, and a slot used for communication with the terminal device is used in units of frames. On the other hand, the slot used for the control signal is used once every 20 frames.

  Returning to FIG. The antenna 10 transmits and receives radio frequency signals to and from the terminal device. That is, at the above-described uplink timing, the antenna 10 receives a radio frequency signal, and at the downlink timing, the antenna 10 transmits a radio frequency signal. The switch 22 switches operations for the transmission unit 24 and the reception unit 26 according to the uplink timing and the downlink timing. That is, at the uplink timing, the switch 22 outputs the radio frequency signal received by the antenna 10 to the reception unit 26, and at the downlink timing, the switch 22 outputs the radio frequency signal output from the transmission unit 24. Output to the antenna 10.

  The receiving unit 26 performs frequency conversion and quadrature detection on the input radio frequency signal to generate a baseband signal. Here, since the baseband signal output from the receiving unit 26 to the modem 28 includes an in-phase component and a quadrature component, the signal should generally be indicated by two signal lines. Only one signal line is shown for the sake of simplicity. The same applies hereinafter. The receiving unit 26 also includes an LNA (Low Noise Amplifier).

  The transmission unit 24 performs orthogonal modulation and frequency conversion on the baseband signal input from the modem 28 to generate a radio frequency signal. The transmission unit 24 outputs the generated radio frequency signal to the switch 22. The transmission unit 24 also includes a PA (Power Amplifier).

  The modem 28 performs modulation / demodulation processing on the baseband signal. During transmission, the modem 28 performs modulation processing. Here, the modulation scheme is assumed to be π / 4 shift QPSK (Quadrature Phase Shift Keying). On the other hand, at the time of reception, the modem 28 executes demodulation processing.

  The baseband processing unit 30 executes processing corresponding to a higher layer than the modem processing on the baseband signal. For example, TDMA / TDD control. Therefore, the baseband processing unit 30 manages the number of slots currently used for communication with the terminal device.

  The power supply unit 14 is supplied with power of a value defined based on the value of power scheduled to be consumed by the communication unit 12 from the outside through an outlet. Here, the value of power scheduled to be consumed in the communication unit 12 is the maximum power consumption defined for the communication unit 12. Further, the value defined based on the value of the power scheduled to be consumed in the communication unit 12 is a value larger than the above-mentioned maximum power consumption and a value corresponding to the power defined by the power company. is there. Furthermore, the power supply unit 14 drives the communication unit 12 with the supplied power. Further, the power supply unit 14 outputs a part of the supplied power to the charging unit based on the control in the charging unit 18.

  The detection unit 16 receives from the baseband processing unit 30 the proportion of one frame occupied by slots used for communication with the terminal device to be communicated. Furthermore, here, the slot used for transmission to the communication target terminal device is targeted as the slot used for communication with the communication target terminal device. That is, “slot 1” to “slot 4” in FIG. 2 are targeted. Since “slot 1” is periodically used by the control signal, it is excluded here, and the ratio of the slot being used in “slot 2” to “slot 4” is accepted. Since the PA of the transmission unit 24 is used in the transmission process, the power consumed in the transmission process is larger than the power consumed in the reception process. As a result, in order to recognize the level of power consumption in the communication unit 12, the slot used for transmission is controlled. The detection unit 16 generates and outputs the control voltage 200 while changing the value according to the ratio of the received slots.

  The charging unit 18 generates a charging current from the supplied power while controlling the value of the charging current based on the control voltage 200. Here, the control voltage 200 corresponds to the actual power value consumed in the communication unit 12. The charging unit 18 performs control so that the value of the charging current decreases when the value of the actual power consumed in the communication unit 12 increases, that is, when the ratio of the used slots increases. On the other hand, when the value of the actual power consumed in the communication unit 12 is reduced, that is, when the ratio of the slots used is reduced, the charging current value is controlled to be increased.

  The battery 20 is charged with a charging current. Further, the battery 20 supplies power for driving the communication unit 12 via the diode D when the supply of power from the outside is stopped like a power failure.

  FIG. 3 shows the charging characteristics of the battery 20. In FIG. 3, the horizontal axis represents time, and the vertical axis represents terminal voltage, charging current, and charging rate. Further, the charging time is 0% when the charging rate is 0%. In the initial stage of charging when the charging rate is about 0 to 50%, the charging rate is rapidly recovered by increasing the value of the charging current supplied to the battery 20. At the same time, the terminal voltage of the battery 20 increases. At that time, the value of the charging current is limited to about 0.25 CA by the constant current characteristic of the charging unit 18. When the charging rate exceeds 50%, the terminal voltage of the battery 20 becomes a substantially constant value, and the value of the charging current gradually decreases. At that time, the charging unit 18 exhibits constant voltage characteristics.

  When the battery 20 is discharged, it is desirable that the battery 20 having a reduced charging rate be charged in a short period in preparation for the next power failure. Therefore, the charging unit 18 should perform charging of the battery 20 with the maximum charging current corresponding to the battery 20. However, the power supplied from the outside is also used for the operation of the communication unit 12. Therefore, in this embodiment, the value of the charging current is changed according to the value of the power actually consumed in the communication unit 12. That is, since the communication unit 12 uses many slots, if the power consumption is large, the charging unit 18 decreases the value of the charging current. On the other hand, since the communication unit 12 uses only a few slots, if the power consumption is small, the charging unit 18 increases the value of the charging current.

  FIG. 4 shows the configuration of the charging unit 18. The charging unit 18 includes a control unit 40, a current sensor unit 42, a variable power source 44, a power source 46, a first operational amplifier OP1, a second operational amplifier OP2, and a first resistor R1 to a fourth resistor R4.

  As a premise, the charging unit 18 has the following functions. That is, when the charging rate of the battery 20 is low, the charging unit 18 performs charging with a maximum charging current value in order to quickly charge the battery 20. Here, the value of the maximum charging current is 0.25 CA. Moreover, in order not to overcharge the battery 20, the charging unit 18 maintains the terminal voltage of the battery 20 at a constant value.

  The control unit 40 controls a voltage value and a current value to be supplied to the battery 20 based on control signals from the first operational amplifier OP1 and the second operational amplifier OP2. Here, the current value corresponds to the value of the charging current, and the voltage value corresponds to the value of the terminal voltage of the battery 20. The charging current to be supplied to the battery 20 is output in the direction of the first resistor R1.

  The current sensor unit 42 generates a current proportional to the voltage from the voltage corresponding to the charging current generated at both ends of the first resistor R1, and outputs the current to the second resistor R2. Therefore, the value of the generated current is proportional to the value of the charging current.

  The first operational amplifier OP1 compares the voltage at the variable power supply 44 with the voltage by the second resistor R2, and generates a control signal that makes the value of the current supplied to the second resistor R2 constant. The first operational amplifier OP1 outputs a control signal to the control unit 40. Here, since the value of the current supplied to the second resistor R2 is proportional to the value of the charging current, the first operational amplifier OP1 realizes a constant current function with respect to the charging current. Further, the voltage of the variable power source 44 is controlled based on the control voltage 200. Therefore, by controlling the control voltage 200, the control unit 40 controls the value of the charging current.

  The second operational amplifier OP2 compares the voltage at the power source 46 with the voltage divided by the third resistor R3 and the fourth resistor R4, and outputs a control signal that makes the voltage value output from the control unit 40 constant. Generate. The second operational amplifier OP2 outputs a control signal to the control unit 40. Therefore, the second operational amplifier OP <b> 2 realizes a constant voltage function with respect to the terminal voltage of the battery 20.

  FIG. 5 shows the output characteristics of the charging unit 18. In the figure, the horizontal axis represents the charging current, and the vertical axis represents the terminal voltage. A solid line indicates a case where the value of the charging current is maximum, and indicates a case where the number of slots used by the communication unit 12 is small. The terminal voltage indicates “battery charging voltage” which is a predetermined value, and the charging current indicates “0.25 CA”. On the other hand, when the number of slots used by the communication unit 12 increases, the state transits to a dotted line state. In this example, the charging current indicates “0.1 CA” while maintaining the terminal voltage.

  The operation of base station apparatus 100 configured as above will be described. FIG. 6 is a flowchart showing a charging procedure in base station apparatus 100. The detection unit 16 detects the number of downlink slots used by the communication unit 12 (S10). If the number of slots is greater than 0 (Y in S12), the number of slots is greater than 1 (Y in S14), and the number of slots is greater than 2 (Y in S16), the detection unit 16 responds to the number of slots 3 The control voltage 200 is set (S18). On the other hand, if the number of slots is not greater than 2 (N in S16), the detection unit 16 sets the control voltage 200 corresponding to the number of slots 2 (S24).

  On the other hand, if the number of slots is not greater than 1 (N in S14), the detection unit 16 sets the control voltage 200 corresponding to the number of slots 1 (S22). On the other hand, if the number of slots is not greater than 0 (N in S12), the detection unit 16 sets the control voltage 200 corresponding to the number of slots 0 (S20). The charging unit 18 adjusts the value of the charging current with the control voltage 200 (S26). The charging unit 18 charges the battery 20 based on the charging current (S28).

  Furthermore, modified examples in which the configuration of the detection unit 16 is different will be described. The detection unit 16 in the modified example measures the value of power consumed in the communication unit 12 and generates the control voltage 200 based on the measured power value. That is, the charging unit 18 operates so that the value of the charging current decreases if the measured power value is large, and operates so that the value of the charging current increases if the measured power value is small. Again, the detection unit 16 targets the value of power consumed in the transmission process as the value of power consumed in the communication unit 12.

  FIG. 7 is a flowchart showing another charging procedure in base station apparatus 100. The detection unit 16 measures power consumption in the transmission process of the communication unit 12 (S50). If the measured power consumption is larger than the threshold value (Y in S52), the detection unit 16 sets the control voltage 200 when it is larger than the threshold value (S54). On the other hand, if the measured power consumption is not greater than the threshold value (N in S52), the detection unit 16 sets the control voltage 200 when it is equal to or less than the threshold value (S56). The charging unit 18 adjusts the value of the charging current with the control voltage 200 (S58). The charging unit 18 charges the battery 20 based on the charging current (S60).

  According to the embodiment of the present invention, the value of power supplied to the base station apparatus is used in the communication unit while maintaining a value defined based on the value of power scheduled to be consumed in the communication unit. Since the value of the charging current is controlled according to the slot ratio, the battery can be charged while suppressing an increase in power to be supplied to the base station apparatus. Further, since the power consumed in the communication unit is based on the ratio of the slots being used, it is easy to grasp the power consumed in the communication unit. Further, since the use of the slot is determined inside the base station apparatus, no error occurs in the detection of the ratio of the slot used.

  In addition, an increase in power consumption can be suppressed in order to grasp power consumed in the communication unit. In addition, since the slot used for transmission is a control target, the processing can be simplified while suppressing a decrease in accuracy of power consumption estimation. Further, since the power actually consumed in the communication unit is measured, the power consumed in the communication unit can be accurately grasped. In addition, since the slot used for transmission is controlled, the measurement is simplified. In addition, since the value of the power supplied to the base station apparatus is defined based on the value of the power scheduled to be consumed in the communication unit, it can be suppressed to a value equivalent to the case where no battery is provided. Moreover, since the value of electric power can be reduced, an increase in cost can be suppressed. In addition, since the battery is provided, it is possible to prevent the service from being stopped even in the event of a power failure.

  The present invention has been described based on the embodiments. This embodiment is an exemplification, and it will be understood by those skilled in the art that various modifications can be made to combinations of the respective constituent elements and processing processes, and such modifications are also within the scope of the present invention. is there.

  In the embodiment of the present invention, the detection unit 16 estimates the actual power consumed in the communication unit 12 based on the number of slots used for transmission or the power consumed in the transmission process. However, the present invention is not limited to this, and for example, estimation may be performed including the case of reception. That is, the detection unit 16 may estimate the actual power consumed in the communication unit 12 based on the number of slots used for communication or the power consumed in communication processing. According to this modification, the actual power consumed in the communication unit 12 is accurately estimated. That is, it is only necessary to derive a value corresponding to the actual power consumed in the communication unit 12.

  In the embodiment of the present invention, the detection unit 16 and the charging unit 18 control the value of the charging current based on the number of slots used for transmission. However, the present invention is not limited to this. For example, the charging current may be supplied during a period when the slot is not used, and the supply of the charging current may be stopped during the period when the slot is used. According to this modification, an increase in charging current during the period in which the slot is used can be further suppressed. That is, it is only necessary to perform communication processing and charge the battery in the value of power scheduled to be consumed in the communication unit.

  In the embodiments of the present invention, the communication system has been described as being a second generation cordless telephone system. However, the present invention is not limited thereto, and may be another wireless communication system such as a third generation mobile phone system. According to this modification, the present invention can be applied to various communication systems. That is, any communication system may be used as long as the amount of communication varies and the power consumption also varies.

It is a figure which shows the structure of the base station apparatus which concerns on the Example of this invention. It is a figure which shows the structure of the frame format formed in the communication part of FIG. It is a figure which shows the charge characteristic of the battery of FIG. It is a figure which shows the structure of the charging part of FIG. It is a figure which shows the output characteristic of the charging part of FIG. It is a flowchart which shows the procedure of charge in the base station apparatus of FIG. It is a flowchart which shows the procedure of another charge in the base station apparatus of FIG.

Explanation of symbols

  10 antenna, 12 communication unit, 14 power supply unit, 16 detection unit, 18 charging unit, 20 battery, 22 switch, 24 transmission unit, 26 reception unit, 28 modem, 30 baseband processing unit, D diode, 100 base station device.

Claims (6)

A communication unit that communicates with a terminal device to be communicated;
Power of a value defined based on the value of power scheduled to be consumed in the communication unit is supplied from the outside, the communication unit is driven by the supplied power, and a charging current is generated from the supplied power A power supply,
A battery that is charged by a charging current generated in the power supply unit and that supplies power for driving the communication unit when the supply of external power is stopped;
A control unit that controls a value of a charging current generated by the power supply unit based on a value of actual power consumed in the communication unit;
A base station apparatus comprising: The communication unit forms a frame including a plurality of slots, and performs communication with a communication target terminal device by using a predetermined slot included in the frame.
The control unit uses a ratio of a slot used for communication with a communication target terminal device in one frame formed by the communication unit as a value of actual power consumed in the communication unit. The base station apparatus according to claim 1.   The base station according to claim 2, wherein the control unit targets a slot used for transmission to a communication target terminal device as a slot used for communication with a communication target terminal device. apparatus. A measuring unit that measures a value of power consumed in the communication unit;
The base station apparatus according to claim 1, wherein the control unit uses a value of power measured by the measurement unit as a value of actual power consumed by the communication unit.   The base station apparatus according to claim 4, wherein the measurement unit measures a value of power consumed in transmission processing as a value of power consumed in the communication unit. In a base station device including a communication circuit that communicates with a terminal device to be communicated,
Power of a value defined based on the value of power scheduled to be consumed in the communication circuit is supplied from the outside, and the communication circuit is driven by the supplied power.
A battery characterized by generating a charging current from the supplied power while controlling the value of the charging current based on the value of the actual power consumed in the communication circuit, and supplying the generated charging current to the battery Charging method.

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