JP4524219B2 - Flying capacitor voltage measuring device - Google Patents

Description

  The present invention relates to a flying capacitor type voltage measuring apparatus, and more particularly to a flying capacitor type voltage measuring apparatus capable of specifying the type of failure and the location of a failure in a measurement system.

As a device for measuring the voltage of each individual battery (voltage source) constituting a high-voltage power source in a high-voltage power source configured by connecting a large number of batteries (voltage source) in series like a power source of an electric vehicle, There is a flying capacitor type voltage measuring device. Such an apparatus is disclosed in, for example, Japanese Patent Application Laid-Open No. 11-248755 (Patent Document 1).
Japanese Patent Laid-Open No. 11-248755

  However, in the above-described conventional apparatus, when the switch of the multiplexer connected to the voltage source is short-circuited, the circuit is short-circuited when measuring the multi-voltage source. Further, it is impossible to specify the type of failure or the location of the failure in the measurement system.

  In view of the above problems, an object of the present invention is to provide a flying capacitor type voltage measuring apparatus capable of specifying the type of failure and the location of a failure in a measurement system.

According to the first aspect of the present invention, a high voltage power source including N voltage sources connected in series, a flying capacitor, and (N + 1) voltage detection terminals connected to the N voltage sources are connected to the flying capacitor. A flying capacitor type voltage measuring apparatus having a multiplexer including (N + 1) voltage sample switches to be selectively connected, a voltage measuring means, and a sample voltage measuring switch for supplying a voltage across the flying capacitor to the voltage measuring means. The multiplexer includes an odd-numbered voltage detection terminal among (N + 1) voltage detection terminals connected to the N voltage sources connected in series to one terminal side of the flying capacitor. First multiplexer selectively connected, and even-numbered voltage detection among the (N + 1) voltage detection terminals A second multiplexer for selectively connecting a child to the other terminal side of the flying capacitor, wherein the flying capacitor type voltage measuring device is provided between the multiplexer and the flying capacitor, the voltage sample of the multiplexer A failure that is closed when the flying capacitor is charged by closing the switch, and that is opened when the voltage sample switch is opened and when the sample voltage measuring switch is supplied to the voltage measuring means by supplying both-end voltage from the flying capacitor. Based on the voltage measurement result of each voltage source by the detection switch and the voltage measuring means, it is determined whether only the measured value of the nth voltage source V (n) is normal and the measured values of all the remaining voltage sources are abnormal. The first determination means for determining and the first determination means determine the nth If only the measured value of the pressure source V (n) is normal and the measured values of all the remaining voltage sources are determined to be abnormal, whether or not the measured value of the nth voltage source V (n) is a completely normal value. If the measured value of the nth voltage source V (n) is also determined to be abnormal by the second determining means for determining the first and the first determining means, the nth voltage source V (n) The measurement value of the nth voltage source V (n) is determined to be a complete normal value by the third determination means for determining whether or not the measurement abnormal value is zero volts and the second determination means. In this case, the first estimation unit that estimates that a short fault has occurred in the voltage measurement line of the nth voltage source V (n) and the second determination unit include the nth voltage source V ( If the measurement value of n) is not determined to be a complete normal value, the voltage measurement line of the nth voltage source V (n) When the second estimation means for estimating that a rare short fault occurs and the third determination means determine that the measured abnormal value of the nth voltage source V (n) is zero volts, The third estimation unit that estimates that an open failure has occurred in the voltage measurement line of the n-th voltage source V (n), and the third determination unit include the n-th voltage source V (n). If the measured abnormal value is not determined to be zero volts, it further comprises fourth estimating means for estimating that an abnormality of the nth voltage source V (n) has occurred .

According to a second aspect of the present invention, in the flying capacitor type voltage measuring device according to the first aspect, the positive side in the voltage measurement line of the nth voltage source V (n) based on the estimation result of the first estimating means. Only a voltage sample switch of the multiplexer connected to the line is closed to determine whether or not the voltage of the nth voltage source V (n) can be measured; and If the determination means determines that the voltage of the n-th voltage source V (n) can be measured, a short circuit failure has occurred in the negative line of the voltage measurement lines of the n-th voltage source V (n). If it is not determined by the fifth estimation unit that estimates that the voltage is generated and the fourth determination unit that the voltage of the n-th voltage source V (n) can be measured, the n-th voltage Voltage of source V (n) Wherein the short-circuit fault in the positive line of the measurement line is further provided with a sixth estimating means for estimating that occurred.

According to a third aspect of the present invention, a high voltage power source including N voltage sources connected in series, a flying capacitor, and (N + 1) voltage detection terminals connected to the N voltage sources are connected to the flying capacitor. A flying capacitor type voltage measuring apparatus having a multiplexer including (N + 1) voltage sample switches to be selectively connected, a voltage measuring means, and a sample voltage measuring switch for supplying a voltage across the flying capacitor to the voltage measuring means. The multiplexer includes a first to an Nth voltage sample switch of the (N + 1) voltage sample switches and one terminal of the flying capacitor, the voltage sample switch to the flying capacitor, respectively. N diodes connected in polarity conducting to the capacitor; Between the second (N + 1) -th voltage sample switch of the (N + 1) voltage sample switches and the other terminal of the flying capacitor, the polarity is conducted from the flying capacitor to the voltage sample switch, respectively. The flying capacitor type voltage measuring device is provided between the multiplexer and the flying capacitor, and is closed when charging the flying capacitor by closing a voltage sample switch of the multiplexer. A failure detection switch that is opened when the voltage sample switch is opened and the sample voltage measurement switch is closed to supply the voltage measurement means with the voltage across the flying capacitor, and the voltage measurement means Fifth determination means for determining whether or not the measured value of the nth voltage source V (n) is equal to or higher than the upper limit of the standard or lower than the lower limit based on the voltage measurement result of the voltage source; When the determination means determines that the measured value of the nth voltage source V (n) is equal to or greater than the upper limit of the standard, the nth voltage source V (n) and (n−1) th A sixth determination means for measuring a series voltage of the voltage source V (n-1) of the first and determining whether or not the measured value is equal to the measured value of the nth voltage source V (n); If the fifth determination means determines that the measured value of the nth voltage source V (n) is not more than the lower limit, is the measured value of the nth voltage source V (n) zero volts? The seventh determination means for determining whether or not, and the measurement value of the nth voltage source V (n) is determined to be zero volts by the seventh determination means. If not, an eighth determination unit that measures the voltage of the (n + 1) th voltage source V (n + 1) and determines whether or not the measured value is a value equal to or higher than the upper limit of the standard; When it is determined by the sixth determining means that the measured value is equal to the measured value of the nth voltage source V (n), the (n−1) th voltage source V (n−1) When the measured value measured by the seventh estimating means for estimating a short fault in the voltage measurement line and the sixth determining means is not determined to be equal to the measured value of the nth voltage source V (n) Alternatively, if the measured value measured by the eighth determining means is not determined to be equal to or higher than the upper limit of the standard, the eighth estimation is performed to estimate that the nth voltage source V (n) is abnormal. And the seventh determination means, the measured value of the nth voltage source V (n) is zero. A ninth estimating means for estimating that the nth voltage source V (n) is abnormal or an open failure has occurred in the voltage measurement line; and the eighth determining means, When it is determined that the measured value is equal to or greater than the upper limit of the standard, it is estimated that a rare short fault has occurred in the voltage measurement line of the nth voltage source V (n). And an estimation means.

According to a fourth aspect of the present invention, in the flying capacitor type voltage measuring device according to the third aspect, the voltage measuring means sets the voltage measurement line estimated as a short-circuit failure on the positive side based on the estimation result of the seventh estimating means. Voltage source V (n−1) is measured, the measured value is estimated as the voltage of the voltage source V (n−1), and the voltage measurement line presumed to be short-circuited is the negative voltage source. The voltage of V (n-2) is measured, the measured value is estimated as the voltage of the voltage source V (n-2), and the voltage other than the voltage sources V (n-1) and V (n-2) The voltage source V is measured, and the voltage source V (n-1) and V (n-) are subtracted from the measured value of the voltage source V (n-1) or V (n-2). It is estimated that it is the voltage of voltage sources other than 2).

A fifth aspect of the present invention is the flying capacitor type voltage measuring device according to any one of the first to fourth aspects, further comprising a warning unit that warns of an estimation result of the estimation unit. And

According to claims 1 and 3 Symbol mounting of the invention, by providing the failure detection switch, when the short-circuit failure switch multiplexer occur, without causing secondary fault, it is possible to detect the short circuit failure . When the voltage across the flying capacitor is read by the voltage measuring means, the floating line from the multiplexer to the flying capacitor can be electrically cut off by opening the failure detection switch, thus improving noise characteristics such as prevention of radio wave resonance. In addition, the type and location of the failure can be estimated.

According to invention of Claim 2 , the kind and location of a failure can be estimated further .

According to the fourth aspect of the present invention, it is possible to accurately estimate the voltage of the voltage source even when a failure occurs.

According to the fifth aspect of the invention, it is possible to warn of the occurrence of a failure.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  (First Embodiment) FIG. 1 is a circuit diagram showing the configuration of a flying capacitor type voltage measuring apparatus according to a first embodiment of the present invention.

  The flying capacitor type voltage measuring apparatus includes a first multiplexer 1 and a second multiplexer 2 connected to voltage detection terminals T1 to T6 of a high-voltage power supply V, a bipolar flying capacitor 3, a sample voltage measuring switch 4, and voltage measuring means. A microcomputer (hereinafter referred to as a microcomputer) 7, an I / F (interface) circuit 8, and a failure detection switch 9.

  High-voltage power supply V includes N voltage sources (for example, single cells) V1-V5 connected in series (in this embodiment, for example, N = 5). Each of the voltage sources V1 to V5 has the same voltage, and is connected to (N + 1) (for example, six in this embodiment) voltage detection terminals T1 to T6.

  The first multiplexer 1 has one terminal connected to each of the voltage detection terminals T1, T3, and T5 via current limiting resistors R1, R3, and R5 for short circuit prevention, and the other terminal connected to the failure detection switch 9. Voltage sample switches S1, S3, S5. The second multiplexer 2 has one terminal connected to each of the voltage detection terminals T2, T4, and T6 via current limiting resistors R2, R4, and R6 for preventing a short circuit, and the other terminal connected to the failure detection switch 9. Includes voltage sample switches S2, S4, S6.

  The sample voltage measurement switch 4 includes a switch 4 a having one terminal connected to one terminal of the flying capacitor 3 and a switch 4 b having one terminal connected to the other terminal of the flying capacitor 3. The other terminals of the switches 4 a and 4 b are connected to the input side of the I / F circuit 8.

  The I / F circuit 8 converts the voltage across the flying capacitor 3 supplied via the sample voltage measurement switch 4 into a voltage with respect to the ground potential, and is constituted by, for example, a voltage dividing circuit or a differential amplifier circuit. . The output side of the I / F circuit 8 is connected to the input port A / D 1 of the microcomputer 7. The microcomputer 7 is supplied with the drive voltage from the power supply + Vcc to the power supply port Vcc.

  The failure detection switch 9 includes a switch 9a connected between one terminal of the first multiplexer 1 and the flying capacitor 3, and a switch 9b connected between the second multiplexer 2 and the other terminal of the flying capacitor 3. including.

  Next, the voltage measurement operation in the normal measurement mode of the flying capacitor type voltage measuring apparatus having the above-described configuration will be described. First, voltage samples of the first multiplexer 1 from the state in which the voltage sample switches S1 to S6 of the multiplexers 1 and 2 and the switches 9a and 9b of the failure detection switch 9 and the switches 4a and 4b of the sample voltage measurement switch 4 are all open. When the switch S1, the voltage sample switch S2 of the second multiplexer 2 and the switches 9a and 9b of the failure detection switch 9 are closed in conjunction with each other, the voltage source V1, the voltage detection terminal T1, the current limiting resistor R1, the voltage sample switch S1, The switch 9a, the flying capacitor 3, the switch 9b, the voltage sample switch S2, the current limiting resistor R2, and the voltage detection terminal T2 form a closed circuit. Thereby, the voltage of the voltage source V1 is charged in the flying capacitor 3 so that the terminal side of the flying capacitor 3 connected to the voltage sample switch S1 has a positive polarity.

  Next, the voltage sample switches S1 and S2 and the switches 9a and 9b are opened in conjunction with each other, the switches 4a and 4b of the sample voltage measuring switch 4 are closed for a predetermined period, and the voltage across the flying capacitor 3, that is, the voltage of the voltage source V1 is set. This is supplied to the input port A / D 1 of the microcomputer 7 through the sample voltage measurement switch 4 and the I / F circuit 8. Thereby, the supplied both-end voltage is A / D converted, and the value is read by the microcomputer 7 as a digital value indicating the voltage of the voltage source V1.

  Next, when the voltage sample switches S2 and S3 and the switches 9a and 9b of the failure detection switch 9 are closed in conjunction with each other, the voltage source V2, the voltage detection terminal T2, the current limiting resistor R2, the voltage sample switch S2, the switch 9b, and flying The capacitor 3, the switch 9a, the voltage sample switch S3, the current limiting resistor R3, and the voltage detection terminal T3 form a closed circuit. Thereby, the voltage of the voltage source V2 has a polarity opposite to that at the time of measurement of the voltage source V1, that is, the terminal side of the flying capacitor 3 connected to the voltage sample switch S2 has a positive polarity. Charged.

  Next, the voltage sample switches S2 and S3 and the switches 9a and 9b are opened in conjunction with each other, the switches 4a and 4b of the sample voltage measuring switch 4 are closed for a predetermined period, and the voltage across the flying capacitor 3, that is, the voltage of the voltage source V2 is set. This is supplied to the input port A / D 1 of the microcomputer 7 through the sample voltage measurement switch 4 and the I / F circuit 8. Thereby, the supplied both-end voltage is A / D converted, and the value is read by the microcomputer 7 as a digital value indicating the voltage of the voltage source V2.

  Similarly, the switching timings of the switches of the first multiplexer 1 and the second multiplexer 2 are sequentially multiplexed by the combination of the voltage sample switches S3 and S4, S4 and S5, S5 and S6, and the voltage sources are respectively supplied. Values indicating the voltages V3, V4, and V5 are read by the microcomputer 7.

  Next, the operation of the failure determination mode for detecting a failure during the above-described normal measurement mode will be described with reference to the flowcharts shown in FIGS. This failure determination mode is performed based on control by the CPU 7.

  First, as a result of sequentially measuring the voltage of each voltage source in the normal measurement mode, it is determined whether only the n-th voltage source V (n) has a normal value and all the measurement results of the remaining voltage sources are abnormal values. (Step S1; first determination means). Here, the influence of the short failure of the voltage sample switch affects the measurement values of all the voltage sources, but the normal measurement is performed by opening the switches 9a and 9b of the failure detection switch 9 when reading into the microcomputer 7. Therefore, it can be determined that a short circuit failure has occurred in the voltage measurement line of the voltage source that is the only normal measurement value.

  If the answer to step S1 is Yes, it is then determined whether or not the measured voltage of the nth voltage source V (n) is a complete normal value (step S2; second determination means). In this case, the normal value is given a wide range, and it is determined whether or not the normal value is a completely normal value that is not a lower normal value. For example, the normal value range of a single voltage source with a voltage of 5 V is set to 4.8 to 5.0 V. If the measured value is 5.0 V, it is a completely normal value, and if it is lower than 5.0 V, the normal value is lower. Value.

  If the answer to step S2 is Yes (that is, if it is a completely normal value), then it is estimated that the voltage measurement line of the nth voltage source V (n) is short-circuited (step S3; first estimating means). . Further, based on this estimation result, a display or buzzer (not shown) as alarm means is driven to warn of a short circuit failure. If the answer to step S2 is No (that is, if it is not a complete normal value but a lower normal value within the range of normal values), then the rare of the voltage measurement line of the nth voltage source V (n) A short failure is estimated (step S4; second estimation means). Further, based on this estimation result, a display or buzzer (not shown) as alarm means is driven to alarm a rare short-circuit failure.

  On the other hand, if the answer to step S1 is No, it is then determined that an open failure of the voltage measurement line of the nth voltage source V (n) from which the abnormal value is measured or a voltage source abnormality (step S5). Further, based on this determination, a display or buzzer (not shown) is driven to warn of a voltage source abnormality. Next, it is determined whether or not the measured abnormal value of the nth voltage source V (n) is 0 (zero) volts (step S6; third determination means). If the answer is Yes, then it is estimated that the voltage measurement line of the nth voltage source V (n) is open (step S8; third estimation means). Further, based on this estimation result, an indicator or buzzer (not shown) serving as a warning means is driven to warn of an open failure. If the answer to step S6 is No, it is then estimated that the nth voltage source V (n) is abnormal (step S7; fourth estimation means). Further, based on the estimation result, a display unit and a buzzer (not shown) serving as a warning unit are driven to warn of a voltage source abnormality.

  In this way, only the nth voltage source V (n) has a normal value, and the operations of steps S1 to S8 based on the determination of whether or not the measurement results of the remaining voltage sources are all abnormal values result in the nth voltage source. It is estimated that the short-circuit fault, short-circuit fault or open fault of the voltage measurement line of V (n), or the abnormality of the n-th voltage source V (n). In addition, each failure or abnormality is alarmed by driving a display or buzzer (not shown) as alarm means. Each failure or abnormality is alerted in a distinguishable form.

  Next, when it is determined as a short failure or an open failure of the voltage measurement line of the nth voltage source V (n) as in step S3 or S8, the process proceeds to the failure measurement mode in step S9.

  In this failure time measurement mode, first, it is determined whether or not there is a short circuit failure (step S10). If the answer is No (that is, if it is an open failure), then the voltage value of the n-th voltage source V (n) in the open part is estimated (step S11). This estimated value is calculated by subtracting (total of measured values of voltage sources other than the open line) from all voltage collective measured values.

If the answer to step S10 is Yes (ie, if it is a short circuit fault), then only the voltage sample switch on the + side line of the abnormal line is closed to determine whether or not voltage measurement is possible (step S12 ; fourth) Determination means ). If the answer is yes, then it is estimated that the voltage sample switch on the negative side of the abnormal line is short-circuited (step S13; fifth estimation means). Further, based on this estimation result, a not-shown indicator or buzzer as alarm means is driven to warn of a short failure of the voltage sample switch on the negative side line of the abnormal line. Next, the process proceeds to step S15.

  If the answer to step S12 is No, it is estimated that a short circuit fault has occurred in the voltage sample switch on the + side line of the abnormal line (step S14; sixth estimation means). Also, based on this estimation result, a not-shown indicator or buzzer as alarm means is driven to warn of a short circuit fault of the voltage sample switch on the + side line of the abnormal line. Next, the process proceeds to step S15.

  In step S15, it is estimated that a single voltage source including a short line can be measured. In addition, it is estimated that the total value of a plurality of series voltage sources that are total odd numbers can be measured. For example, the total value of (V (n) + V (n + 1) + V (n + 2)) or the total value of (V (n) + V (n + 1) + V (n + 2) + V (n + 3) + V (n + 4)) can be measured. is there.

  As described above, when it is estimated that the voltage measurement line of the voltage source V (n) is out of order, it is possible to calculate the voltages of some of the voltage sources as soon as possible while issuing an alarm to that effect.

  (Second Embodiment) FIG. 4 is a circuit diagram showing the configuration of a flying capacitor type voltage measuring apparatus according to a second embodiment of the present invention.

  In FIG. 4, the flying capacitor type voltage measuring apparatus includes a multiplexer 12, a unipolar flying capacitor 13, a sample voltage measuring switch 4, a microcomputer 7, and an I / F (interface) circuit 8 connected to a voltage detection terminal of a high voltage power source V. , A failure detection switch 9, diodes 17a to 17e, 18b to 18f, and correction circuits 19-1 to 19-5 as correction means.

  High-voltage power supply V includes N voltage sources (for example, single cells) V1-V5 connected in series (in this embodiment, for example, N = 5). Each of the voltage sources V1 to V5 has the same voltage and is connected to (N + 1) (for example, 6 in this embodiment) voltage detection terminals T1 to T6.

  The multiplexer 12 includes (N + 1) (for example, 6 in this embodiment) voltage sample switches 12a to 12f connected to the voltage detection terminals T1 to T6, respectively. The first to fifth voltage sample switches 12a to 12e are connected to one terminal (for example, + terminal) of the flying capacitor 13 via the five diodes 17a to 17e and the failure detection switch 9, respectively. Has been. The diodes 17a to 17e are respectively connected in such a polarity that the voltage sample switches 12a to 12e are electrically connected to the flying capacitor 13, that is, the anode is on each voltage sample switch 12a to 12e side and the cathode is on the flying capacitor 13 side. Has been.

  The second to sixth voltage sample switches 12b to 12f are connected to the other terminal (for example, the-terminal) of the flying capacitor 13 via the five diodes 18b to 18f and the failure detection switch 9, respectively. Has been. Each of the diodes 18b to 18f has a polarity that conducts from the flying capacitor 13 to each of the voltage sample switches 12b to 12f. That is, the anode is on the flying capacitor 13 side and the cathode is on the voltage sample switch 12b to 12f side. It is connected to the.

  The sample voltage measurement switch 4 includes a switch 4 a connected to the + terminal of the flying capacitor 13 and a switch 4 b connected to the − terminal of the flying capacitor 13. The switches 4 a and 4 b are connected to the input side of the I / F circuit 8.

  The output side of the I / F circuit 8 is connected to the input port A / D 1 of the microcomputer 7. In the microcomputer 7, the voltage from the power supply + Vcc is supplied to the power supply port Vcc, and correction circuits 19-1 to 19-5 are connected to the input ports A / D2 to A / D6, respectively. The correction circuit 19-1 includes a resistor 19a-1 and diodes 19b-1 and 19c-1 connected in series to the + Vcc power source, and the connection point between the resistor 19a-1 and the diode 19b-1 is the input port A of the microcomputer 7. / D2 is connected. Similarly, the correction circuit 19-5 includes a resistor 19a-5 and diodes 19b-5 and 19c-5 connected in series to the + Vcc power source, and the connection point between the resistor 19a-5 and the diode 19b-5 is the microcomputer 7's. It is connected to the input port A / D6. (The correction circuits 19-2 to 19-4 having the same configuration are also connected to the input ports A / D2 to A / D5, respectively, but are not shown here.)

  The diode is a multi-terminal (four terminals in this embodiment) packaged product as a diode array containing at least two elements, one of which is for the voltage measurement line and the other one is for the correction circuit. . For example, a combination of the diode 17a and the diode 19b-1, a combination of the diode 18b and the diode 19c-1, a combination of the diode 17e and the diode 19b-5, and a combination of the diode 18f and the diode 19c-5 are each in the same package product. (The diodes in the correction circuits 19-2 to 19-4 (not shown) are also in the same package product by the same combination as described above.)

  The failure detection switch 9 includes a switch 9a connected between the diodes 17a to 17e and the positive terminal of the flying capacitor 13, and a switch 9b connected between the diodes 18b to 18f and the negative terminal of the flying capacitor 13.

  Next, the voltage measurement operation in the normal measurement mode of the flying capacitor type voltage measuring apparatus having the above-described configuration will be described. First, the voltage sample switches 12a and 12b, the failure detection switch, and the voltage sample switches 12a to 12f of the multiplexer 12, the switches 9a and 9b of the failure detection switch 9, and the switches 4a and 4b of the sample voltage measurement switch 4 are all opened. When the nine switches 9a and 9b are closed in conjunction with each other, the voltage source V1, the voltage detection terminal T1, the voltage sample switch 12a, the diode 17a, the switch 9a, the flying capacitor 13, the switch 9b, the diode 18b, the voltage sample switch 12b, and the voltage detection A closed circuit is formed by the terminal T2. Thereby, the voltage of the voltage source V1 is charged in the flying capacitor 13.

  Next, the voltage sample switches 12a and 12b and the switches 9a and 9b are opened in conjunction with each other, the switches 4a and 4b of the sample voltage measurement switch 4 are closed for a predetermined period, and the voltage across the flying capacitor 13 is changed to the sample voltage measurement switches 4 and I. It is supplied to the input port A / D1 of the microcomputer 7 via the / F circuit 8. Thereby, the supplied both-end voltage is A / D converted, and the value is read by the microcomputer 7 as a digital value indicating the voltage of the voltage source V1.

  Next, after the voltage charged in the flying capacitor 13 is sufficiently discharged by a reset switch (not shown) or the like, the voltage sample switches 12b and 12c and the switches 9a and 9b of the failure detection switch 9 are closed in conjunction with each other, A closed circuit is formed by V2, voltage detection terminal T2, voltage sample switch 12b, diode 17b, switch 9a, flying capacitor 13, switch 9b, diode 18c, voltage sample switch 12c, and voltage detection terminal T3. Thereby, the voltage of the voltage source V2 is charged in the flying capacitor 13.

  Next, the voltage sample switches 12b and 12c and the switches 9a and 9b are opened in conjunction with each other, the switches 4a and 4b of the sample voltage measurement switch 4 are closed for a predetermined period, and the voltage across the flying capacitor 13 is changed to the sample voltage measurement switches 4 and I. It is supplied to the input port A / D1 of the microcomputer 7 via the / F circuit 8. Thereby, the supplied both-end voltage is A / D (analog / digital) converted, and the value is read by the microcomputer 7 as a digital value indicating the voltage of the voltage source V2.

  Similarly, digital values indicating respective voltages of the voltage sources V3 to V5 are read by the microcomputer 7 by the combination of the voltage sample switches 12c and 12d, 12d and 12e, 12e and 12f, respectively.

  In the above description, the voltage of one voltage source is measured. However, this apparatus is not limited to this, and two or more voltage sample switches can be opened or closed by opening or closing any combination. It is also possible to measure the voltage when the voltage source is connected in series. Therefore, in the second embodiment, not only voltage measurement between the odd-numbered and even-numbered voltage detection terminals but also voltage measurement between the odd-numbered and odd-numbered and between even-numbered and even-numbered is possible.

  In addition, when a combination of two voltage sample switches is closed to form a closed circuit, a voltage loss due to a forward voltage drop of two diodes inserted into the closed circuit occurs. Correction is performed by the correction circuits 19-1 to 19-5.

  That is, when the diodes 17a and 18b are included in the closed circuit for voltage measurement, the microcomputer 7 supplies the digital value of the voltage supplied to the input port A / D1 and measured to the input port A / D2. The digital value read by A / D conversion of the voltage corresponding to the forward voltage drop of the two diodes 19b-1 and 19c-1 of the correction circuit 19-1 is canceled out by the digital value. Make corrections. This correction is performed, for example, by the microcomputer 7 performing an operation of adding the voltage supplied to the input port A / D1 and the voltage supplied to the input port A / D2.

  Similarly, when the diodes 17e and 18f are included in the closed circuit for voltage measurement, the microcomputer 7 supplies the input port A / D6 to the digital value of the voltage supplied to the input port A / D1 and measured. A digital value obtained by A / D converting and reading the voltage corresponding to the forward voltage drop of the two diodes 19b-5 and 19c-5 of the correction circuit 19-5 to be supplied is canceled out. Make corrections. This correction is performed, for example, by the microcomputer 7 performing an operation of adding the voltage supplied to the input port A / D1 and the voltage supplied to the input port A / D6.

  In the second embodiment, a combination of the diode 17a and the diode 19b-1, a combination of the diode 18b and the diode 19c-1, a combination of the diode 17e and the diode 19b-5, a combination of the diode 18f and the diode 19c-5, and the like. Since each is the same package product, it is not only the same lot in production, but also on the same wafer and at the same point, so it shows almost the same characteristics, and the forward voltage drop characteristic that varies with the ambient temperature is also Since they are affected by exactly the same effect, they are the same, making it possible to ideally correct the voltage loss and to improve the voltage source voltage detection accuracy.

  In addition, according to the second embodiment of the present invention, since a secondary failure does not occur even when the voltage sample switch is short-circuited, safety is improved. In addition, the failure of the voltage sample switch can be detected. Further, since a flying capacitor having a single polarity can be used, the cost can be reduced and the design flexibility can be increased. Furthermore, the deterioration state of the connection part between the odd-numbered and even-numbered voltage sources can be monitored.

  Next, the operation of the failure determination mode for detecting a failure during the operation of the normal measurement mode will be described with reference to the flowcharts shown in FIGS. This failure determination mode is performed based on control by the CPU 7.

  First, during the measurement of the voltage of each voltage source in the normal measurement mode, when the voltage of the nth voltage source V (n) is measured, the measured voltage is equal to or higher than the upper limit or lower limit of the standard. (Step S21; fifth determination means).

  If the measured voltage is equal to or higher than the upper limit, then the voltage of the n-th voltage source V (n) and the (n−1) th voltage source V (n−1) connected in series is measured ( Step S22). Next, whether the measured voltage of the nth voltage source V (n) is equal to the measured series voltage of the nth voltage source V (n) and the (n + −) th voltage source V (n + 1). It is determined whether or not (step S23; sixth determination means).

  If the answer to step S23 is yes, it is estimated that a short fault has occurred in the voltage measurement line of the (n-1) th voltage source V (n-1) (step S24; seventh estimation means). Further, based on this estimation result, a display or buzzer (not shown) as alarm means is driven to warn of a short circuit failure.

  On the other hand, if the answer to step S23 is no, it is estimated that the voltage source V (n) is abnormal in voltage (step S25; eighth estimating means). That is, in this case, it is estimated that the voltage of the voltage source to be measured is abnormally large, not the short circuit failure as described above.

  Next, returning to step S21, if the measured voltage of the voltage source V (n) is equal to or lower than the lower limit in the standard, it is then determined whether or not the measured voltage is 0 (zero) volts. (Step S26; seventh determination means).

  If the answer to step S26 is yes, it is then estimated that the voltage abnormality of the nth voltage source V (n) or the open failure of the voltage measurement line of the nth voltage source V (n) (step S27; ninth). Estimation means).

  Next, if the answer to step S26 is no (ie, if the voltage of the nth voltage source V (n) exceeds 0 (zero) volts and indicates a value below the lower limit of the standard), then , The voltage of the (n + 1) th voltage source V (n + 1) is measured (step S28).

  Next, it is determined whether or not the measured voltage is equal to or higher than the upper limit in the standard (step 29; eighth determination means). If the answer is no, the process proceeds to step S25, where the answer is yes. If so, the process proceeds to step S30.

  In step S30 (tenth estimating means), it is estimated that a rare short fault has occurred in the voltage measurement line of the nth voltage source V (n).

  Thus, the operation of steps S21 to S30 based on the determination of whether the measured voltage of the nth voltage source V (n) is greater than or equal to the standard upper limit or less than the lower limit results in the (n−1) th voltage source V ( n) a voltage short-circuit fault in the voltage measurement line, or an abnormality in the n-th voltage source V (n), a short-circuit fault in the voltage measurement line of the n-th voltage source V (n), or the n-th voltage source V ( It is estimated that the abnormality is n) or the voltage measurement line is short-circuited, or the n-th voltage source V (n) is short-circuited.

  Next, when it is estimated that a short fault has occurred in the voltage measurement line of the n-th voltage source V (n) as in step S24, the process proceeds to the short fault measurement mode in step S31.

  In this short failure measurement mode, first, the switch of the multiplexer 12 corresponding to the (n−1) th voltage source V (n−1) with the voltage measurement line determined to be a short failure in the failure determination mode as the + side. The switches 9a and 9b of the failure detection switch 9 are closed in conjunction with each other, and the flying capacitor 13 is charged by the voltage of the voltage source V (n-1). Next, during measurement, the failure detection switches 9a and 9b are opened to measure the voltage of the voltage source V (n-1), and the measured value is estimated as the voltage of the voltage source V (n-1) (step S32). .

  Next, it is determined whether or not the voltage source V (n−1) is not the lowest voltage source (step S33). In the circuit of FIG. 4, the lowest voltage source is the voltage source V5. If the answer is yes, then n = n + 1, the n-th voltage source V (n) one lower than the voltage source V (n−1) is selected, and the voltage source V (n−1) described above is selected. Voltage measurement is performed in the same procedure as voltage measurement (step S34).

  Next, the voltage value of the voltage source V (n) is calculated (step S35). This calculation is performed by subtracting the measured value of the voltage source V (n−1) obtained in step S32 from the measured value of the voltage source V (n) obtained in step S34. Next, returning to step 33, while it is determined Yes in step 33 (that is, the voltage source V (n-1) is not the lowest voltage source), the operations in steps S34 and S35 are repeated. The voltage of the voltage source one level lower than the measured voltage source is sequentially calculated.

  On the other hand, if the answer to step S33 is No (that is, if the voltage source V (n) is the lowest voltage source), then the voltage source whose negative voltage measurement line is determined to be the negative in the failure determination mode is the voltage source. Voltage measurement of V (n-2) is performed (step S36). In this measurement, first, the switch of the multiplexer 12 corresponding to the (n-2) th voltage source V (n-2) and the switches 9a and 9b of the failure detection switch 9 are closed in conjunction with each other, and the voltage source V (n-2 ) To charge the flying capacitor 13. Next, at the time of measurement, the failure detection switches 9a and 9b are opened.

  Next, it increments to n = n + 1, selects a voltage source V (n-3) that is one higher than the voltage source V (n-2), and is the same as the voltage measurement of the voltage source V (n-2) described above. Voltage measurement is performed according to the procedure (step S37). Next, the voltage value of the voltage source V (n-3) is calculated (step S38). This calculation is performed by subtracting the measured value of the voltage source V (n-2) obtained in step S36 from the measured value of the voltage source (n-3) obtained in step S37.

  Next, it is determined whether or not the voltage source V (n-2) is the highest voltage source (step S39). In the circuit of FIG. 4, the highest voltage source is the voltage source V1. If the answer is No, the process then returns to Step S37, and while it is determined No in Step 39 (that is, the voltage source V (n-2) is not the highest voltage source), the operations in Steps S37 and S38 are performed. Are repeated, and the voltage of the voltage source one level higher than the voltage source measured and calculated before is sequentially calculated.

  On the other hand, if the answer to step S39 is Yes (that is, if the voltage source V (n-3) is the highest voltage source), then the process returns to step S32.

  Next, when it is estimated as a rare short failure in the voltage measurement line of the nth voltage source V (n) as in step S30, the process proceeds to the rare short failure measurement mode in step S40.

  In this rare short fault measurement mode, the voltage of the voltage source V (n) of the rare short fault is measured as the series voltage of all the voltage sources V1 to V5, and the nth voltage is obtained from the obtained total voltage batch measurement result. The calculation is performed by subtracting the sum of the measurement results of the single voltage source excluding the source V (n) (step S41).

  As described above, when it is estimated that the voltage measurement line of the voltage source V (n−1) is short-circuited or the voltage measurement line of the voltage source V (n) is short-circuited, the emergency is generated while issuing an alarm to that effect. Thus, the voltage of each voltage source can be calculated.

  Next, a specific example of short circuit fault estimation in the voltage measurement line of the voltage source V (n−1) will be described below. For example, when the voltage sample switch 12c is short-circuited for some reason, when measuring the voltage of the third voltage source V3, the voltage sample switch 12c, 12d is closed and measured, so there is no problem. The measured value can be estimated as it is as the voltage of the voltage source V3.

  Next, when measuring the voltage of the fourth voltage source V4, if the voltage sample switches 12d and 12e and the switches 9a and 9b are closed in conjunction with each other, the voltage sample switch 12c is short-circuited. The potential of the voltage source V3 plus the voltage source V4 is generated at the connection point of the flying capacitor 13, and the − (minus) side potential of the voltage source V4 is generated at the connection point of the switch 9b and the flying capacitor 13. As a result, the flying capacitor 3 is charged with the voltage of the voltage source V3 plus the voltage source V4 in the flying capacitor 13.

  Next, the voltage sample switches 12d and 12e and the switches 9a and 9b are opened in conjunction with each other, the switches 4a and 4b of the sample voltage measurement switch 4 are closed for a predetermined period, and the voltage across the flying capacitor 13 is changed to the sample voltage measurement switches 4 and I. It is supplied to the input port A / D1 of the microcomputer 7 via the / F circuit 8. Thereby, the supplied both-ends voltage is A / D converted, and the value is read by the microcomputer 7 as a digital value indicating the voltage of the voltage source V3 plus the voltage source V4.

  Although the microcomputer 7 measures the voltage of the fourth voltage source V4, the measured voltage is equal to or higher than the standard upper limit and is the voltage of the voltage source V3 plus the voltage source V4. From step S24, it is estimated that a short circuit fault has occurred in the voltage measurement line of the voltage source V3, and an alarm is issued.

  As described above, when it is estimated that there is a short-circuit failure in the voltage measurement line of the voltage source V3, the voltage source V3 is subsequently measured in step 32 in the short-failure measurement mode, and the measured value is the voltage source. Estimated as the voltage of V3.

  Next, at the time of measurement of the voltage source V4, as described above, since the measured value is the voltage of the voltage source V3 plus the voltage source V4, the voltage of the voltage source V4 is changed to the voltage by the operations of steps S34 and S35. It is estimated by subtracting the measured value of the voltage source V3 from the measured value of the source V4 (that is, the measured value of the voltage source V4 minus the measured value of the voltage source V3). Similarly, the voltage of the voltage source V5 is estimated by subtracting the measured value of the voltage source V4 from the measured value of the voltage source V5 (that is, the measured value of the voltage source V5 minus the measured value of the voltage source V4).

  Since the voltage source V5 is the lowest voltage source, when the measurement of the voltage source V5 is finished, the voltage source V2 is measured in step S36, and the measured value is estimated as the voltage of the voltage source V2.

  Next, at the time of measurement of the voltage source V1, as described above, since the measured value is the voltage of the voltage source V1 plus the voltage source V2, the voltage of the voltage source V1 is changed to the voltage by the operations of steps S37 and S38. It is estimated by subtracting the measurement value of the voltage source V2 from the measurement value of the source V1 (that is, the measurement value of the voltage source V1−the measurement value of the voltage source V2).

  As described above with respect to the first and second embodiments, according to the present invention, even when a failure occurs in the measurement system, voltage measurement including the influence of the failure is possible. If the measured value is measured in the above, by comparing the voltage of the abnormal value and the measured value when the voltage source where the abnormal value was measured and the voltage source before and after that are measured simultaneously, the type of failure, Not only is it possible to locate the fault location, but it is also possible to quickly estimate the voltage source voltage without stopping the voltage measurement.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this, A various deformation | transformation and application are possible.

  For example, in the flying capacitor type voltage measuring apparatus according to the second embodiment, for example, an addition value obtained by separately measuring and adding the voltage source V1 and the voltage source V2 and a series voltage of the voltage source V1 and the voltage source V2 are measured. By comparing the measured values, when the added value <measured value, the voltage measurement line including the voltage detection terminal T2 is degraded, and the degradation status of each voltage measurement line can also be grasped.

It is a circuit diagram which shows the structure of the flying capacitor system voltage measuring apparatus which concerns on the 1st Embodiment of this invention. (First embodiment) It is a flowchart explaining the operation | movement of the failure determination mode of the flying capacitor type voltage measuring device which concerns on the 1st Embodiment of this invention. (First embodiment) It is a flowchart explaining the operation | movement of the failure determination mode of the flying capacitor type voltage measuring device which concerns on the 1st Embodiment of this invention. (First embodiment) It is a circuit diagram which shows the structure of the flying capacitor system voltage measuring apparatus which concerns on the 2nd Embodiment of this invention. (Second Embodiment) It is a flowchart explaining the operation | movement of the failure determination mode of the flying capacitor type voltage measuring device which concerns on the 2nd Embodiment of this invention. (Second Embodiment) It is a flowchart explaining the operation | movement of the failure determination mode of the flying capacitor type voltage measuring device which concerns on the 2nd Embodiment of this invention. (Second Embodiment)

Explanation of symbols

V high voltage power supply V1 to V5 voltage source T1 to T6 voltage detection terminal 1 first multiplexer 2 second multiplexer S1 to S6 voltage sample switch 3 flying capacitor 4 sample voltage measurement switch 7 microcomputer (voltage measurement means, first to eighth Determination means, first to tenth estimation means)
9 Fault Detection Switch 12 Multiplexer 12a-12f Voltage Sample Switch 13 Flying Capacitor 14 Sample Voltage Measurement Switch 17a-17f Diode 18a-18f Diode

Claims (5)

A high voltage power source including N voltage sources connected in series, a flying capacitor, and (N + 1) voltage detection terminals connected to the N voltage sources are selectively connected to the flying capacitor (N + 1). A flying capacitor type voltage measuring device having a multiplexer including a plurality of voltage sample switches, a voltage measuring unit, and a sample voltage measuring switch for supplying a voltage across the flying capacitor to the voltage measuring unit;
The multiplexer selectively connects an odd-numbered voltage detection terminal among (N + 1) voltage detection terminals connected to the N voltage sources connected in series to one terminal side of the flying capacitor. And a second multiplexer for selectively connecting an even-numbered voltage detection terminal of the (N + 1) voltage detection terminals to the other terminal side of the flying capacitor,
The flying capacitor type voltage measuring device is:
The flying capacitor is provided between the multiplexer and the flying capacitor, and is closed when the flying capacitor is charged by closing the voltage sample switch of the multiplexer, and the flying by opening the voltage sample switch and closing the sample voltage measuring switch. A failure detection switch that is opened when a voltage across the capacitor is supplied to the voltage measuring means;
Based on the voltage measurement result of each voltage source by the voltage measuring means, a first determination is made as to whether only the measurement value of the nth voltage source V (n) is normal and the measurement values of all the remaining voltage sources are abnormal. Determining means,
When the first determination unit determines that only the measurement value of the nth voltage source V (n) is normal and the measurement values of all the remaining voltage sources are abnormal, the nth voltage source V (n) Second determination means for determining whether or not the measured value is a completely normal value;
When the first determination means determines that the measured value of the nth voltage source V (n) is also abnormal, it is determined whether the measured abnormal value of the nth voltage source V (n) is zero volts. Third determining means for
When the second determination means determines that the measured value of the nth voltage source V (n) is a complete normal value, a short circuit in the voltage measurement line of the nth voltage source V (n). First estimating means for estimating that a failure has occurred;
If the measured value of the nth voltage source V (n) is not determined to be a complete normal value by the second determining means, a rare short in the voltage measurement line of the nth voltage source V (n). Second estimating means for estimating that a failure has occurred;
When the third determination means determines that the measured abnormal value of the nth voltage source V (n) is zero volts, an open failure occurs in the voltage measurement line of the nth voltage source V (n). Third estimating means for estimating that the
When the third determination means does not determine that the measured abnormal value of the nth voltage source V (n) is zero volts, it is estimated that an abnormality of the nth voltage source V (n) has occurred. A flying capacitor type voltage measuring apparatus , further comprising: a fourth estimating means . In the flying capacitor type voltage measuring device according to claim 1,
Based on the estimation result of the first estimation means, only the voltage sample switch of the multiplexer connected to the plus line in the voltage measurement line of the n-th voltage source V (n) is closed, and the n-th voltage source switch is closed. Fourth determination means for determining whether or not the voltage of the voltage source V (n) can be measured;
If the fourth determination means determines that the voltage of the nth voltage source V (n) can be measured, the negative side line of the voltage measurement lines of the nth voltage source V (n) A fifth estimating means for estimating that a short-circuit failure has occurred;
If the fourth determination unit does not determine that the voltage of the nth voltage source V (n) can be measured, the positive side of the voltage measurement line of the nth voltage source V (n) And a sixth estimating means for estimating that a short circuit failure has occurred in the line.
A flying capacitor type voltage measuring apparatus characterized by the above. A high voltage power source including N voltage sources connected in series, a flying capacitor, and (N + 1) voltage detection terminals connected to the N voltage sources are selectively connected to the flying capacitor (N + 1). A flying capacitor type voltage measuring device having a multiplexer including a plurality of voltage sample switches, a voltage measuring unit, and a sample voltage measuring switch for supplying a voltage across the flying capacitor to the voltage measuring unit;
The multiplexer conducts from the voltage sample switch to the flying capacitor between the first to Nth voltage sample switches of the (N + 1) voltage sample switches and one terminal of the flying capacitor, respectively. Between the N diodes connected in polarity and the second to (N + 1) th voltage sample switches of the (N + 1) voltage sample switches and the other terminal of the flying capacitor, the flying N diodes connected in polarity conducting from a capacitor to the voltage sample switch;
The flying capacitor type voltage measuring device is:
The flying capacitor is provided between the multiplexer and the flying capacitor, and is closed when the flying capacitor is charged by closing the voltage sample switch of the multiplexer, and the flying by opening the voltage sample switch and closing the sample voltage measuring switch. A failure detection switch that is opened when a voltage across the capacitor is supplied to the voltage measuring means;
A fifth determination for determining whether or not the measured value of the nth voltage source V (n) is equal to or higher than the upper limit of the standard or lower than the lower limit based on the voltage measurement result of each voltage source by the voltage measuring means. Means,
When the fifth determination means determines that the measured value of the nth voltage source V (n) is equal to or greater than the upper limit of the standard, the nth voltage source V (n) and (n -1) A sixth determination that measures the series voltage of the first voltage source V (n-1) and determines whether or not the measured value is equal to the measured value of the nth voltage source V (n) Means,
When the fifth determining means determines that the measured value of the nth voltage source V (n) is not more than the lower limit, the measured value of the nth voltage source V (n) is zero volts. Seventh determination means for determining whether or not,
If the measurement value of the nth voltage source V (n) is not determined to be zero volts by the seventh determination means, the voltage of the (n + 1) th voltage source V (n + 1) is measured and measured. An eighth determination means for determining whether or not the value is equal to or greater than a standard upper limit;
When it is determined by the sixth determining means that the measured value measured is equal to the measured value of the nth voltage source V (n), the (n−1) th voltage source V (n−1). Seventh estimating means for estimating a short-circuit fault in the voltage measurement line of
If the measured value measured by the sixth determining means is not determined to be equal to the measured value of the nth voltage source V (n), or the measured value measured by the eighth determining means is An eighth estimating means for estimating that the nth voltage source V (n) is abnormal when it is not determined that the value is equal to or greater than the upper limit;
When the seventh determination means determines that the measured value of the nth voltage source V (n) is zero volts, the nth voltage source V (n) is abnormal or there is an open failure in the voltage measurement line. Ninth estimating means for estimating occurrence;
When it is determined by the eighth determination means that the measured measurement value is equal to or greater than the upper limit of the standard, a rare short fault occurs in the voltage measurement line of the nth voltage source V (n). And 10th estimating means for estimating that
A flying capacitor type voltage measuring apparatus characterized by the above. In the flying capacitor type voltage measuring device according to claim 3,
The voltage measuring means measures the voltage of the voltage source V (n−1) with the voltage measurement line estimated as a short-circuit failure on the + side based on the estimation result of the seventh estimating means, and the measured value is a voltage. The voltage of the source V (n-1) is estimated, the voltage measurement of the voltage source V (n-2) is performed with the voltage measurement line estimated to be a short circuit failure as the negative side, and the measured value is the voltage source V (n -2), the voltage of the voltage source other than the voltage sources V (n-1) and V (n-2) is measured, and the voltage source V (n-1) or By subtracting the measured value of V (n-2), the voltage of the voltage source other than the voltage sources V (n-1) and V (n-2) is estimated.
A flying capacitor type voltage measuring apparatus characterized by the above. In the flying capacitor type voltage measuring device according to any one of claims 1 to 4,
Alarm means for warning any estimation result of the estimation means is further provided.
A flying capacitor type voltage measuring apparatus characterized by the above.

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