JP2008191011A - Measuring device, control program for the measuring device, and recording medium with the control program of the measuring device stored - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a measuring device capable of accurately measuring the voltage of a battery power supply, with an appropriate timing. <P>SOLUTION: This voltage measuring device comprises an A/D converter 11 for A/D conversion of the voltage of the battery into a digital value, a correcting section 32 for correcting the digital value, and a reference voltage determining IC 12 for commanding correction start of the measured value by the correcting section 32, when the voltage of the battery is a reference voltage V or lower. Thus, the measured value of the voltage can be corrected, with a timing, on the voltage which is to be measured with accuracy. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a measuring device that measures the voltage of a battery power supply, a control program for the measuring device, and a recording medium that records the control program for the measuring device.

  Conventionally, a device or a system for driving a battery as a main power source has been widely used. As described above, in the device or system driven using the battery power source, the amount of current consumed varies depending on the operation state of the device or system, and therefore, the amount of decrease in the battery voltage varies depending on each operation state. For example, even when the battery voltage at which the device or system can operate is guaranteed in the standby state, the voltage may be lower than the driveable voltage of the device or system during driving. Therefore, the minimum voltage that enables the device or system to operate even when the current consumption amount is maximum can be defined as the battery life in the device or system.

  By the way, in order to stably operate the above-described apparatus or system, it is necessary to accurately measure the battery voltage and monitor whether or not the voltage defined as the battery life has been reached. When the battery voltage falls below a certain voltage, it is required to isolate the battery from the circuit that consumes the battery power source or to notify the user of the battery consumption state.

  However, in the case of a configuration in which voltage measurement is performed using an AD converter, there is a problem that variations in the voltage output from the power supply circuit cause an error in the conversion result of AD conversion by the AD converter.

  In view of this, for example, Patent Documents 1 to 4 disclose an apparatus that accurately measures a voltage or corrects a measurement result of a voltage including an error.

  More specifically, in Patent Document 1, a reference voltage and a reference current are measured, an error between the measured value and a true value is obtained, and an approximate curve is calculated from the error. Then, a correction value of the voltage and current signals using an AD converter that obtains a correction value for each section in the input signal based on the approximate curve and subtracts or adds the correction value to the input signal to correct the voltage. Is disclosed.

  Patent Document 2 discloses a voltage measurement system that cancels fluctuations in an output voltage using a reference voltage obtained by dividing an output voltage detected from a power supply line.

  Patent Document 3 discloses an AD / DA conversion circuit that digitally converts an output voltage when a reference voltage generating unit is activated under a predetermined power supply voltage environment and stores the value in a memory.

  Further, in Patent Document 4, a conversion error calculation circuit that calculates an error using output data from an analog-digital converter and reference voltage data, output data from the conversion error circuit, and output data from the analog-digital converter are corrected. A battery level display system having a conversion error correction circuit is disclosed.

However, these conventional techniques do not instruct execution of accurate voltage measurement at an appropriate timing in the battery power supply as in the present application.
Japanese Patent Laid-Open No. 4-370769 (released on December 24, 1992) JP 2000-356657 A (released on December 26, 2000) JP 2002-290236 A (released on October 4, 2002) JP 2006-53089 A (published February 23, 2006)

  By the way, when the above-described battery is a primary battery such as a dry battery, the battery voltage during discharge decreases with time and reaches the voltage defined as the battery life as shown in the discharge curve shown in FIG. Further, even if the battery is a secondary battery, if a constant discharge is continued, a similar discharge curve is drawn and the voltage defined as the battery life is reached.

  In the vicinity of the voltage defined as the battery life, it is necessary to accurately measure the voltage and estimate the battery life accurately for the following reasons. In other words, if the voltage measurement result includes an error, it is erroneously determined that the battery life has been reached even though the battery life has been reached, or the battery life has not been reached. This is because problems such as determining that the battery has reached the end of its life and isolating the battery occur.

  For this reason, an apparatus or system driven by a battery power source is required to have a configuration that can accurately measure the battery voltage when the voltage reaches a voltage in the vicinity defined as the battery life.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a measuring apparatus, a measuring apparatus control program, and a measuring apparatus that can accurately measure the voltage of a battery power supply at an appropriate timing. It is to realize a recording medium on which the control program is recorded.

  In order to solve the above-described problems, a measuring apparatus according to the present invention converts a voltage applied from a battery power source into a digital value, and obtains a measured value of the voltage, and the measured value converter Comparing the reference voltage, which is a reference voltage value for determining whether or not it is necessary to accurately measure the voltage of the battery power supply, with the voltage applied from the battery power supply And an instruction unit for instructing start of correction of the measurement value by the correction means when the voltage becomes equal to or lower than the reference voltage.

  The reference voltage is a voltage that is higher than the voltage defined as the battery life and can be set in a voltage range that may be erroneously recognized as the battery life.

  Moreover, as said battery power supply, primary batteries, such as a dry battery, are mentioned, for example, such that the voltage decreases with time and reaches a voltage defined as the battery life. Furthermore, a secondary battery that draws a discharge curve similar to that of the primary battery and reaches a voltage defined as the battery life when a constant discharge is continued as the battery power source can be mentioned.

  According to the above configuration, since the measurement value conversion unit is provided, the measurement result of the voltage of the battery power supply can be handled as a digital value. In addition, since the correction unit is provided, the measurement value converted by the measurement value conversion unit can be corrected even if it includes an error.

  In addition, since the instruction unit is provided, the correction process by the correction unit for the measurement result of the battery voltage can be performed at the timing when the voltage of the battery power source should be measured with high accuracy.

  Therefore, the measuring apparatus according to the present invention has an effect that it is possible to accurately measure the voltage of the battery power supply at an appropriate timing.

  In the measurement apparatus according to the present invention, in the above-described configuration, the correction unit is configured such that a reference value that is a digital value without a measurement error related to a predetermined voltage and a voltage applied by a battery power supply are the predetermined voltage. It is preferable that the measurement value is corrected based on the difference from the measurement value obtained sometimes.

  The measuring apparatus according to the present invention further includes an estimating unit that estimates the life of the battery based on the measured value in the configuration described above. When the measured value is corrected by the correcting unit, the estimating unit Preferably, the battery life is estimated based on the corrected measurement value.

  According to the configuration described above, since the estimation means is provided, the life of the battery can be estimated. Furthermore, when the measurement value is corrected by the correction means, the battery life can be estimated based on the corrected measurement value, and therefore the battery life can be estimated accurately at an appropriate timing.

  In the above-described configuration, the measuring apparatus according to the present invention includes an output unit that outputs at least one of information on the battery life estimated by the estimating unit and information on the measured value corrected by the correcting unit. It is preferable that it is comprised.

  According to the above configuration, since the output unit is provided, the user who uses the apparatus or system using the battery power source according to the present invention can be notified of information on the battery life and the measurement value corrected by the correction unit. it can.

  In the above-described configuration, the measurement apparatus according to the present invention is activated by the power supplied from the battery power source, and switches the connection between the battery power source and the measurement value conversion unit to ON or OFF. And the instruction unit determine that the voltage of the battery power source is equal to or lower than the reference voltage, connect the battery power source and the measurement value conversion unit so that the voltage is applied to the measurement value conversion unit. It may be configured to include switching instruction means for instructing the switching unit to switch on.

  According to the above configuration, since the switching unit and the switching instruction unit are provided, the measurement can be performed only when necessary without always measuring the voltage of the battery power supply. For this reason, compared with the structure which always measures the voltage of a battery power supply, the electric power of the battery power consumed by the voltage measurement of the said measuring apparatus can be reduced.

  Further, the measurement apparatus according to the present invention is activated by the electric power supplied from the battery power source in the configuration described above, and the battery power source and the measured value so that a voltage is applied to the measured value conversion unit. A switching unit that switches on or off the connection between the conversion unit at predetermined intervals, and the battery power source and the measured value conversion unit when the instruction unit determines that the voltage of the battery power source is equal to or lower than the reference voltage. Switching instruction means for instructing the switching unit so that the interval of the timing of turning on the connection between the switching unit and the switching unit becomes shorter than the interval before it is determined to be equal to or less than the reference voltage. Also good.

  According to the above configuration, since the switching unit and the switching instruction unit are provided, for example, the battery power source and the measured value conversion are performed so that the voltage is applied at predetermined intervals in a period in which the voltage measurement does not need to be performed with high accuracy. The connection with the part is turned on. However, when the instruction unit determines that the voltage of the battery power source is equal to or lower than the reference voltage, that is, when it is necessary to measure the voltage with high accuracy, the connection between the battery power source and the measured value conversion unit It can be set so that the timing interval of turning on is shortened.

  For this reason, compared with the structure which always measures the voltage of a battery power supply, the electric power of the battery power consumed by the voltage measurement of the said measuring apparatus can be reduced.

  The measurement apparatus may be realized by a computer. In this case, a control program for the measurement apparatus that causes the measurement apparatus to be realized by the computer by causing the computer to operate as the above-described means, and the program are recorded. Computer-readable recording media are also within the scope of the present invention.

  As described above, the measuring device according to the present invention converts the voltage applied from the battery power source into a digital value and solves the above-described problem in order to solve the above-described problem. Measurement value conversion unit, correction means for correcting the measurement value converted by the measurement value conversion unit, and a voltage value serving as a reference for determining whether or not it is necessary to accurately measure the voltage of the battery power source An instruction unit that compares a reference voltage with a voltage applied from a battery power supply and instructs the correction means to start correction of the measured value when the voltage is equal to or lower than the reference voltage. To do.

  Therefore, the measuring apparatus according to the present invention has an effect that it is possible to accurately measure the voltage of the battery power supply at an appropriate timing.

(Embodiment 1)
An embodiment of the present invention will be described below with reference to FIGS. That is, the battery drive system 100 according to the present embodiment is configured such that the power from the battery 2 is supplied to the drive circuit 6 and the like via the power supply circuit 3 as shown in FIG. This is a system driven by supplied electric power. FIG. 1 shows an embodiment (Embodiment 1) of the present invention, and is a diagram showing a main configuration of a battery drive system 100. As shown in FIG.

  The battery drive system 100 according to the present embodiment includes a voltage measurement device (measurement device) 1, a display control unit 5, and a display unit 4 in addition to the battery (battery power source) 2, the power supply circuit 3, and the drive circuit 6 described above. Is further provided. The battery driving system 100 can measure the voltage of the battery 2 by the voltage measuring device 1 and display information on the life of the battery 2 on the display unit 4 from the measured voltage.

  The battery 2 is a primary battery such as a dry battery, for example. When the battery 2 is discharged for a certain period, the battery 2 drops to a voltage defined as the battery life.

  The voltage measuring device 1 measures the voltage applied from the battery 2 to the power supply circuit 3 as shown in FIG. 1, and displays information related to the battery life estimated from the measurement result through the display control unit 5 through the display unit 4. To display.

  The display unit 4 is realized by a display device such as an LCD (liquid crystal display) or a CRT (cathode-ray tube), and is controlled by the display control unit 5, for example, various information such as information on battery life. Display information.

  It should be noted that power is supplied from the power supply circuit 3 to each part of the battery drive system 100. However, for the sake of convenience of explanation, the components other than the connection between the power supply circuit 3 and the drive circuit 6 are omitted here. .

(Configuration of voltage measuring device)
Here, the configuration of the voltage measuring apparatus 1 according to the present embodiment will be described below.

  As shown in FIG. 1, the voltage measuring apparatus 1 according to the present embodiment includes resistors R1 and R2, an AD converter (measured value converting unit) 11, a reference voltage determination IC (indicating unit) 12, and a voltage measuring device control unit ( (Correction means, estimation means, output means) 13 and a memory 14.

  In the voltage measurement apparatus 1 according to the present embodiment, the voltage from the battery 2 is divided into a voltage that can be converted from analog to digital (AD) by the AD converter 11 using the resistor R1 and the resistor R2. The AD converter 11 outputs a digital signal (measured value) based on the divided voltage to the voltage measuring device controller 13.

  In addition, the voltage measuring apparatus 1 includes the reference voltage determination IC 12 as described above, and determines whether or not the voltage divided by the resistors R1 and R2 is equal to or lower than the reference voltage V by the reference voltage determination IC12. You can also do it.

  Here, the reference voltage V is a value larger than the voltage defined as the battery life described above. More precisely, it is a voltage that can be set as a value that is larger than the voltage defined as the battery life by a range that can be taken as a voltage measurement error.

  That is, as described above, the minimum voltage at which the device or system can operate even during the operation in which the amount of current consumption is maximum can be defined as the voltage when the battery 2 is at the lifetime. A voltage larger than the voltage at the time of life, that is, a voltage in a voltage range or more that may be erroneously recognized as the battery life is set as the reference voltage V.

  Therefore, when a large error occurs in the voltage measurement of the battery 2, a voltage with a larger margin than the voltage at the time of battery life can be set as the reference voltage V. When there is almost no error in the voltage measurement result, the voltage at the time of battery life or a voltage slightly higher than this voltage can be set as the reference voltage V.

  Thus, the reference voltage V is appropriately set in consideration of the performance of the battery 2, the amount of current consumed by the battery driving system 100 that drives the battery 2 as a power source, and the error range of the voltage measurement result. The

The reference voltage determination IC 12 compares the divided voltage applied from the battery 2 with the reference voltage V and determines whether or not the voltage is equal to or lower than the reference voltage V. The reference voltage determination IC 12 controls a signal indicating “high” when the voltage is higher than the reference voltage V, and a signal indicating “low” when the voltage is lower than the reference voltage V. To the unit 13. The signals indicating “high” or “low” are collectively referred to as binary signals in this specification.

  The reference voltage determination IC 12 can be realized by, for example, a reset IC that operates as follows. That is, the reference voltage determination IC 12 monitors the voltage from the battery 2 and outputs “high” when the voltage is higher than the reference voltage V, but outputs “low” when the voltage becomes lower than the reference voltage V.

  The reference voltage determination IC 12 is configured to compare the voltage applied from the battery 2 with the reference voltage V as an analog value without converting it into a digital value. For this reason, no error occurs in the comparison process by the reference voltage determination IC 12.

  The memory can be realized by a semiconductor memory such as a ROM, EPROM, EEPROM, flash ROM, etc., and stores a reference value 21. The reference value 21 is a value when the voltage at the reference voltage V is converted into digital data by the AD converter 11 and indicates an ideal value that does not include a measurement error.

  The voltage measurement device control unit 13 performs various controls in each unit of the voltage measurement device 1, and can be realized by, for example, a CPU (central processing unit). The voltage measuring device control unit 13 also grasps the voltage in the battery 2 based on the signal input from the AD converter 11 and determines the life of the battery 2.

  Further, the voltage measuring device control unit 13 measures the digital signal (measured value) input from the AD converter 11 when the binary signal input by the reference voltage determination IC 12 changes from “high” to “low”. It also corrects errors. That is, when voltage measurement is performed using the AD converter 11, variations in the voltage output from the power supply circuit 3 cause an error in the conversion result of AD conversion performed by the AD converter 11. Therefore, the voltage measuring device control unit 13 refers to the reference value 21 and grasps and corrects the measurement error of the voltage measured from the battery 2.

  Further, the voltage measuring device control unit 13 estimates the life of the battery 2 from the digital value input from the AD converter 11 or a value obtained by correcting the digital value, and causes the display unit 4 to display the estimation result. It also instructs the display control unit 5.

(Configuration related to correction of voltage measurement results in a voltage measuring device)
Next, with reference to FIG. 2, a configuration relating to correction of a voltage measurement result in the voltage measurement apparatus 1 according to the present embodiment will be described. FIG. 2 shows an embodiment of the present invention, and shows a software configuration related to correction of a voltage measurement result in the voltage measurement apparatus 1. The voltage measurement device control unit 13 includes a reference value acquisition unit 31, a correction unit (correction unit) 32, and a battery life estimation unit (estimation unit, output unit) 33 as functional blocks. These functional blocks can be realized when the voltage measuring device control unit 13 is a CPU, for example, and the CPU reads a program stored in the ROM or the like into the RAM or the like and executes it.

  The reference value acquisition unit 31 reads the reference value 21 from the memory 14 when determining that the binary signal input from the reference voltage determination IC 12 has changed from “high” to “low”. The reference value acquisition unit 31 transmits the read reference value 21 to the correction unit 32.

  When the correction unit 32 acquires the reference value 21 from the reference value acquisition unit 31, the correction unit 32 corrects the digital value input from the AD converter 11. The correction unit 32 transmits the corrected result to the battery life estimation unit 33.

  That is, the reference voltage determination IC 12 can specify the time point when the voltage applied from the battery 2 reaches the reference voltage V without any measurement error. Then, the correction unit 32 can determine an error included in the digital value based on whether or not the digital value obtained by the AD converter 11 at this time matches the reference value 21.

  When the error is determined in this way, the correction unit 32 creates a correction straight line, which will be described later, reflecting the determined error, and corrects the digital value obtained from the voltage of the battery 2.

  When the correction unit 32 has not acquired the reference value 21 from the reference value acquisition unit 31 or when there is no error in the digital value, the digital value input from the AD converter 11 is directly used as the battery life. It transmits to the estimation part 33.

  The battery life estimation unit 33 estimates the life of the battery 2 based on the digital value received from the correction unit 32. The battery life estimation unit 33 transmits the estimated result to the display control unit 5.

  Here, the correction method according to the measurement result of the voltage of the battery 2 by the correction unit 32 will be described with reference to FIGS. 3 and 4. FIG. 3 is a graph showing a relationship between an ideal battery power supply voltage not including an error and a digital value obtained from the voltage. FIG. 4 is a graph showing the relationship between the voltage of the battery power supply and the digital value obtained from the voltage, and the relationship between the ideal battery power supply voltage without error and the digital value obtained from the voltage. FIG. 4 shows the relationship between the voltage of the battery power source including an error and the digital value obtained from the voltage.

By the way, in the case of an ideal condition in which the power supply voltage Vref in the power supply circuit 3 does not vary, the relationship between the battery voltage Vbat under this condition and the digital value Data obtained from the voltage is a digital value after AD conversion. Assuming that the number of bits of the value is N and the voltage dividing resistors are R1 and R2, the following equation (1) can be obtained.
Data = Vbat × (R2 / (R1 + R2)) / (Vref / (2 ^N )) (1)
Here, when (R2 / (R1 + R2)) × (2 ^N ) = k, the above formula (1) can be expressed as follows.
Data = 1 / Vref × k × Vbat (2)
The relationship between Data and Vbat shown in the above formula (2) is a straight line a1 shown in FIG. 3 when there is no variation in the output from the power supply circuit 3 and an ideal digital value for the voltage is obtained. In the relationship shown in FIG. 3, Data when Vbat becomes the reference voltage V becomes the reference value 21.

  Here, when the measured value of the power supply voltage Vref in the power supply circuit 3 is ideally obtained, it can be indicated by a straight line a1 in FIG.

  On the other hand, when the power supply voltage Vref in the power supply circuit 3 varies so as to be higher than the ideal value, the digital value obtained by AD conversion of the battery voltage Vbat becomes smaller than the digital value of the ideal value, and the straight line shown in FIG. As shown in a3. On the other hand, when the power supply voltage Vref in the power supply circuit 3 varies so as to be lower than the ideal value, the digital value obtained by AD conversion of the battery voltage Vbat becomes larger than the digital value of the ideal value, and is shown by a straight line a2 shown in FIG. It becomes like this.

Here, if the digital value after AD conversion at the actually measured reference voltage V is Dat, it can be expressed as the following mathematical formula (3).
Vbat = (R2 / (R1 + R2)) × V / Dat × reference value (3)
Therefore, the correction unit 32 uses the above mathematical formula (3) to receive the battery voltage Vbat reflecting the measurement error from the digital value Dat at the time of (reference value 21, reference voltage V) received from the reference value acquisition unit 31. And a digital value Data obtained by AD conversion of the battery voltage Vbat (for example, a correction straight line such as a straight line a2 or a3). Then, the correction unit 32 notifies the battery life estimation unit 33 of the obtained relational expression (correction straight line).

  The battery life estimation unit 33 estimates the life of the battery 2 based on the relational expression (correction line) received from the correction unit 32 and transmits the estimated result to the display control unit 5.

  As described above, the voltage measuring apparatus 1 according to the present embodiment corrects the measurement error of the voltage Vbat of the battery 2 when the reference voltage V is reached, and the life of the battery 2 is determined from the result after the correction. Can be estimated.

  For this reason, the voltage measurement apparatus 1 according to the present embodiment can correct the measurement error of the battery voltage Vbat at an appropriate timing at which the battery life should be accurately measured.

  By the way, in the case of the configuration in which the voltage measurement of the battery voltage Vbat is constantly performed, the power from the battery 2 is consumed by this voltage measurement process, and as a result, the battery life of the battery 2 is shortened. In order to measure the voltage of the battery 2 at a desired time, a switch (switching unit) 15 is provided before the voltage is divided and input to the AD converter 11 as shown in FIG. It is preferably configured to be opened and closed.

(Embodiment 2)
The configuration of a voltage measuring device (measuring device) 51 according to another embodiment (second embodiment) of the present invention will be described below with reference to FIGS. FIG. 5 shows another embodiment of the present invention, and is a diagram showing a main configuration of the battery driving system 101. As shown in FIG. FIG. 6 shows another embodiment of the present invention, and is a block diagram showing a software configuration relating to the correction of the voltage Vbat of the battery 2 in the voltage measuring device 51.

  As shown in FIG. 5, the configuration of the voltage measuring device 51 shown in the second embodiment is different from the configuration of the voltage measuring device 1 shown in the first embodiment in that the battery 2, the resistor R1, and the resistor R2 (voltage dividing circuit). The difference is that a switch 15 is further provided between them.

  In addition, the reference voltage determination IC 12 is provided between the switch 15 and the battery 2, and the voltage of the battery 2 before voltage division is input instead of the voltage of the battery 2 after voltage division. Different from the voltage measuring device 51 shown. For this reason, the magnitude of the reference voltage V monitored by the reference voltage determination IC 12 is larger than that in the first embodiment.

  Further, in the voltage measuring device 51, the voltage measuring device control unit (correction means, estimation means, output means, switching instruction means) 43 determines the switch 15 according to the binary signal output from the reference voltage determination IC 12. The voltage measurement device 1 is different from the voltage measurement device controller 13 provided in the voltage measurement device 1 in that opening / closing is instructed.

  That is, the voltage measuring device control unit 43 further includes a switch open / close instruction unit (switching instruction means) 34 as a functional block as shown in FIG. When the “low” signal is received from the reference voltage determination IC 12, the switch open / close instruction unit 34 instructs to close the open switch 15 so that the voltage Vbat of the battery 2 is applied to the AD converter 11. Furthermore, the switch opening / closing instruction unit 34 also instructs the reference value acquisition unit 31 to acquire the reference value 21. Except for the points described above, the voltage measuring device 51 is the same as the voltage measuring device 1 shown in the first embodiment.

  As described above, the voltage measurement device 51 according to the present embodiment is set so that the voltage measurement is not performed until the switch 15 is open until the reference voltage V is reached. When the reference voltage determination IC 12 determines that the voltage of the battery 2 has become equal to or lower than the reference voltage V, it transmits a “low” signal to the voltage measurement device controller 43. In the voltage measuring device control unit 43, the switch open / close instruction unit 34 instructs the switch 15 to close in response to the “low” signal.

  As described above, the voltage measuring device 51 according to the present embodiment can start AD conversion (voltage measurement) by the AD converter 11 when the voltage becomes equal to or lower than the reference voltage V. The power consumption of the battery 2 can be reduced as compared with a configuration in which measurement is always performed.

  The voltage measuring device 51 described above is configured to measure the voltage of the battery 2 when it reaches the reference voltage V or lower and correct the measurement result to estimate the battery life. However, the present invention is not limited to this. For example, it may be configured as follows.

  That is, while the reference voltage V is exceeded, the switch 15 is opened and closed intermittently at a predetermined interval, and the voltage Vbat is measured at every predetermined interval. Even when the voltage Vbat is measured by always turning on the switch 15 from the time when it becomes equal to or lower than the reference voltage V, or the switch 15 is opened and closed at a time interval shorter than the predetermined interval, the voltage Vbat is measured. Good.

  In such a configuration, before reaching the reference voltage V, the voltage Vbat is measured at every predetermined interval, and the voltage Vbat is measured from the time of the reference voltage V or less at a constant time or at an interval shorter than the predetermined interval. can do. For this reason, compared with the structure which always performs AD conversion (voltage measurement) by the AD converter 11 in order to measure the voltage of the battery 2, the power consumption of the battery 2 can be reduced. Therefore, the voltage measuring device 51 according to the present embodiment suppresses the consumption of the battery 2 as described above, and at the reference voltage V or lower, the measured voltage value is corrected at all times or frequently so that the life of the battery 2 is increased. Can be estimated.

  Further, the voltage measuring device 51 according to the present embodiment controls the opening / closing timing of the switch 15 according to an instruction from the voltage measuring device control unit 43 (for example, turns on or off the switch, or turns on the switch). For example, the timing interval is shortened. However, it may be configured to control the opening / closing timing of the switch 15 in accordance with an instruction from the reference voltage determination IC 12. Thus, in the case of controlling the opening / closing timing of the switch 15 according to the instruction from the reference voltage determination IC 12, the instruction is output from the reference voltage determination IC 12 to the switch 15 as follows.

  That is, until the voltage of the battery 2 reaches the reference voltage V, a signal indicating “high” is output from the reference voltage determination IC 12 to the voltage measuring device controller 43. When the voltage of the battery 2 becomes equal to or lower than the reference voltage V, the reference voltage determination IC 12 outputs a signal indicating “low” to the voltage measuring device control unit 43 and turns on the switch 15. Alternatively, a control signal instructing to shorten the interval of timing for turning on the switch is output.

  When the voltage measuring device 51 is configured in this way, the control line extends from the reference voltage determination IC 12 toward the switch 15 instead of the control line extending from the voltage measuring device control unit 43 to the switch 15 in FIG. Become. The voltage measurement device control unit 43 does not have the switch opening / closing instruction unit 34, but has the reference voltage determination IC 12.

  In addition, in the battery drive system 101 which concerns on Embodiment 1 and Embodiment 2, although it was the structure which displays the information regarding a battery life on the display part 4, the content to display is not limited to this. For example, the structure which displays the information regarding the measured value corrected by the correction | amendment part 32 may be sufficient, and the structure which displays the information regarding the battery lifetime and the corrected measured value may be sufficient.

  In this way, when displaying information regarding the corrected measurement value, the correction unit 32 transmits the information regarding the corrected measurement value to the display control unit 5. Then, the display control unit 5 causes the display unit 4 to display the information based on the corrected measurement value received from the correction unit 32.

  The information related to the measurement value is, for example, a relational expression (for example, correction of a straight line a2 or a3 or the like) between the battery voltage Vbat reflecting the measurement error and the digital value Data obtained by AD conversion of the battery voltage Vbat. Straight line).

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

  Finally, each unit of the voltage measurement device control unit 13 included in the voltage measurement device 1 and the voltage measurement device control unit 43 included in the voltage measurement device 51 as a functional block may be configured by hardware logic as follows. Alternatively, it may be realized by software using a CPU.

  In other words, the voltage measuring device 1 and the voltage measuring device 51 include a CPU that executes instructions of a control program that realizes each function, a ROM (read only memory) that stores the program, and a RAM (random access memory) that expands the program. And a storage device (recording medium) such as a memory for storing the program and various data. An object of the present invention is to enable a computer to read program codes (execution format program, intermediate code program, source program) of control programs for the voltage measuring device 1 and the voltage measuring device 51, which are software that realizes the functions described above. This can also be achieved by supplying the recorded recording medium to the voltage measuring apparatus 1 and the voltage measuring apparatus 51, and the computer (or CPU or MPU) reads and executes the program code recorded on the recording medium. .

  Examples of the recording medium include tapes such as magnetic tapes and cassette tapes, magnetic disks such as floppy (registered trademark) disks / hard disks, and disks including optical disks such as CD-ROM / MO / MD / DVD / CD-R. Card system such as IC card, IC card (including memory card) / optical card, or semiconductor memory system such as mask ROM / EPROM / EEPROM / flash ROM.

  Further, the voltage measuring device 1 and the voltage measuring device 51 may be configured to be connectable to a communication network, and the program code may be supplied via the communication network. The communication network is not particularly limited. For example, the Internet, intranet, extranet, LAN, ISDN, VAN, CATV communication network, virtual private network, telephone line network, mobile communication network, satellite communication. A net or the like is available. Also, the transmission medium constituting the communication network is not particularly limited. For example, even in the case of wired such as IEEE 1394, USB, power line carrier, cable TV line, telephone line, ADSL line, etc., infrared rays such as IrDA and remote control, Bluetooth ( (Registered trademark), 802.11 wireless, HDR, mobile phone network, satellite line, terrestrial digital network, and the like can also be used. The present invention can also be realized in the form of a computer data signal embedded in a carrier wave in which the program code is embodied by electronic transmission.

  The measurement apparatus according to the present invention can perform the correction process by the correction unit for the measurement result at the timing when the voltage of the battery power source should be measured with high accuracy. Therefore, the present invention can be widely applied to devices and systems driven by battery power.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows embodiment of this invention and shows the principal part structure of a battery drive system. FIG. 3 is a block diagram illustrating a software configuration relating to correction of a voltage measurement result in the voltage measurement device according to the embodiment of the present invention. It is a graph which shows the relationship between the voltage of the ideal battery power supply which does not contain an error, and the digital value calculated | required from this voltage. It is a graph which shows the relationship between the voltage of a battery power supply, and the digital value calculated | required from the said voltage, The relationship between the ideal battery power supply voltage which does not contain an error, and the digital value calculated | required from this voltage, and the battery power supply containing an error And the relationship between the voltage and the digital value obtained from the voltage. FIG. 5 is a diagram illustrating another embodiment of the present invention and illustrating a configuration of a main part of a battery driving system. It is another embodiment of this invention, and is a block diagram which shows the software structure regarding the voltage correction in a voltage measuring device. It is a figure which shows a prior art and shows an example of the discharge curve in a primary battery.

Explanation of symbols

1 Voltage measuring device (measuring device)
2 batteries (battery power)
11 AD converter (measurement value converter)
12 Reference voltage determination IC (indicator)
13 Voltage measurement device controller (correction means, estimation means, output means)
15 switch (switching part)
21 Reference value 32 Correction unit (correction means)
33 Battery life estimation unit (estimation means, output means)
34 Switch open / close instruction section (switching instruction means)
43 Voltage measurement device controller (correction means, estimation means, output means, switching instruction means)
51 Voltage measuring device (measuring device)
V reference voltage

Claims (8)

A voltage conversion unit that converts a voltage applied from a battery power source into a digital value and sets the measured value of the voltage;
Correction means for correcting the measurement value converted by the measurement value conversion unit;
When the reference voltage, which is a reference voltage value for determining whether or not it is necessary to accurately measure the voltage of the battery power supply, is compared with the voltage applied from the battery power supply, and the voltage is equal to or lower than the reference voltage And an instruction unit for instructing start of correction of the measurement value by the correction means.   The correction means is based on a difference between a reference value that is a digital value without a measurement error related to a predetermined voltage and a measured value obtained when the voltage applied by the battery power source becomes the predetermined voltage. The measuring apparatus according to claim 1, wherein the value is corrected. An estimation means for estimating the lifetime of the battery based on the measured value;
3. The measuring apparatus according to claim 1, wherein when the measurement value is corrected by the correction unit, the estimation unit estimates a battery life based on the corrected measurement value. 4.   The measuring apparatus according to claim 3, further comprising an output unit that outputs at least one of information on the battery life estimated by the estimating unit and information on the measured value corrected by the correcting unit. It is activated by the power supplied from the battery power source,
A switching unit that switches the connection between the battery power source and the measurement value conversion unit on or off;
When the instruction unit determines that the voltage of the battery power source is equal to or lower than the reference voltage, the connection between the battery power source and the measurement value conversion unit is switched on so that the voltage is applied to the measurement value conversion unit. The measurement apparatus according to claim 1, further comprising: a switching instruction unit that instructs the switching unit. It is activated by the power supplied from the battery power source,
A switching unit that switches the connection between the battery power source and the measurement value conversion unit on or off at predetermined intervals so that a voltage is applied to the measurement value conversion unit;
When the instruction unit determines that the voltage of the battery power source is equal to or lower than the reference voltage, the interval before turning on the connection between the battery power source and the measured value conversion unit is determined to be equal to or lower than the reference voltage. The measurement apparatus according to claim 1, further comprising a switching instruction unit that instructs the switching unit to be shorter than the interval.   A control program for operating the measuring apparatus according to any one of claims 1 to 6, wherein the control program is for causing a computer to function as each of the means.   A computer-readable recording medium on which the control program for the measuring apparatus according to claim 7 is recorded.

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