JP6071721B2 - measuring device - Google Patents

Description

  The present invention relates to a measurement apparatus configured to be able to acquire a measurement result based on measurement value data obtained by A / D converting an input signal to be measured.

  For example, when inputting a high-voltage measurement target signal that exceeds the input range to the measurement device, connect the voltage divider to the voltage input section of the measurement device so that the voltage of the measurement target signal is within the input range. When inputting a measurement target signal with a large current exceeding the range to the measurement device, a measurement method is widely implemented in which the current of the measurement target signal is within the inputable range by connecting a shunt to the current input section of the measurement device. ing. However, when a voltage divider or a current divider is used, an error occurs in the measurement value due to the presence of an offset component unique to the voltage divider or the current divider. Therefore, when using a voltage divider or a current divider, the measurement error due to the presence of the offset component is acquired in advance as a correction value (offset value), and the corrected value obtained by correcting the measurement value by this offset value is obtained. There has been proposed a measuring apparatus configured to output a value as a measurement result.

  For example, Japanese Patent Application Laid-Open No. 2012-78282 discloses a power measurement device configured to include an input unit, a calculation unit, and a CPU unit. In this publication, there are two types of power measurement devices disclosed in “Background Art” and the power measurement device disclosed in “Best Mode for Carrying Out the Invention”. Since the power measuring device disclosed in “Background Art” has a general configuration, the power measuring device disclosed in “Background Art” will be mainly described below. The input unit converts an input signal (analog signal) input to the voltage input unit into a digital signal and an A / D converter converts the input signal (analog signal) input to the current input unit into a digital signal. A voltage divider is connected to the voltage input unit, and a current shunt is connected to the current input unit. In addition, the calculation unit includes a voltage calculation unit, a current calculation unit, a power calculation unit, a voltage offset storage unit, a current offset storage unit, and an offset processing unit.

  The voltage calculation unit calculates a voltage value based on the data output from the input unit (A / D converter). The current calculation unit calculates a current value based on the data output from the input unit (A / D converter). The power calculation unit calculates a power value based on the voltage value and the current value calculated by the voltage calculation unit and the current calculation unit. The voltage offset storage unit stores a voltage offset value measured in a state where the input terminal of the voltage divider is short-circuited. The current offset storage unit stores a current offset value measured in a state where the input terminal of the shunt is short-circuited. The offset processing unit is based on the voltage offset value and the current offset value, and DC offset compensation calculation processing of the voltage measurement value and the current measurement value (a correction for subtracting the voltage offset value from the voltage measurement value and subtracting the current offset value from the current measurement value) Process). The CPU unit includes a CPU (Central Processing Unit), an operation unit, a display unit, and the like, and displays a measurement result generated based on the calculation result of the calculation unit on the display unit or transmits it to an external device.

  In this case, in this type of measuring apparatus, the data generated by the input unit is used so that various types of processing can be performed smoothly without configuring the main processing unit with a high-performance computing element having a high manufacturing cost. A configuration is adopted in which a pre-processing unit that performs pre-processing prior to processing by the main processing unit is provided to avoid a situation in which an excessively large burden is imposed on the main processing unit. However, in adopting such a configuration, if the manufacturing cost of the arithmetic circuit constituting the preprocessing unit is excessively high or the configuration of the preprocessing unit becomes excessively complicated, a high-performance arithmetic element The manufacturing cost does not change from that of the main processing unit, and the configuration of the main processing unit with high-performance arithmetic elements can simplify the configuration of the entire power measuring device, so that the preprocessing unit There is no need to install.

  Therefore, in the above power measurement device, an arithmetic circuit can be configured at a lower cost than a high-performance CPU, and a DSP (Digital Signal Processor) that can be configured without complicating the arithmetic circuit is used as a preprocessing unit. An arithmetic unit is configured. As a result, it is possible to reduce the burden on the CPU without causing an increase in manufacturing cost. In the power measurement device disclosed in “Best Mode for Carrying Out the Invention” of this publication, the main part of the offset processing function in the above arithmetic unit is configured by an FPGA (Field Programmable Gate Array). ing. Therefore, in the power measurement device disclosed in this publication, the offset processing unit in the arithmetic unit configured by a DSP or FPGA converts the voltage value or current value output from the input unit into the voltage offset value or current offset value. Since the correction is made based on this and the result is output to the CPU (CPU), the CPU can smoothly display and record the measurement result in parallel with other various processes.

JP 2012-78282 A (page 2-9, FIG. 1-9)

  However, the conventional power measuring apparatus has the following problems to be solved. That is, in the conventional power measurement device, in order to avoid the situation where an excessively large burden is applied to the CPU unit (CPU) without causing an increase in manufacturing cost, in the offset processing unit of the arithmetic unit configured by a DSP or FPGA. A configuration in which the measured value is corrected and output to the CPU unit (CPU) is employed. In this case, in the conventional power measuring apparatus, as described above, the measured value measured with the input terminal of the voltage divider short-circuited is stored in the voltage offset storage unit as the voltage offset value, and the input terminal of the shunt is short-circuited. A configuration is adopted in which the measured value measured in the state is stored in the current offset storage unit as a current offset value.

  Therefore, in the conventional power measurement device, the voltage offset value and current offset value and the measurement value before correction corrected using the voltage offset value and current offset value have the same number of digits. The subsequent measured values are also the same number of digits as the voltage offset value, the current offset value, and the measured value before correction. For this reason, in the conventional power measuring device, there is a problem that it is not possible to obtain a highly accurate measurement result with a number of digits exceeding the resolution of the A / D converter in the input unit.

  The present invention has been made in view of such problems, and a main object of the present invention is to provide a measuring apparatus that can acquire a highly accurate measurement result.

  In order to achieve the above object, the measuring apparatus according to claim 1 is based on a signal processing unit that performs A / D conversion on an input signal to be measured and outputs first measurement value data, and a correction value that is generated in advance. A correction processing unit that corrects a value of the first measurement value data to generate second measurement value data, and a first calculation process that is defined in advance for the second measurement value data. A pre-processing unit having a first calculation processing unit for generating third measurement value data, and a second calculation process preliminarily defined for the third measurement value data to generate fourth measurement value data A second processing unit, and a main processing unit that executes a measurement result output process that outputs the generated fourth measurement value data as a measurement result related to the input signal, wherein the second calculation The processing unit is used as the input signal. The third measurement value data generated by the first calculation process for a predetermined number of the first measurement value data output from the signal processing unit in a state where a positive value acquisition signal is input; And a value of N digits lower than the lowest digit in the value of the first measurement value data (N is a natural number) based on one of the prescribed numbers of the first measurement value data. The fourth measurement value having a value in which the lowest digit is equal to the lowest digit in the correction value in the second calculation process is configured to execute the correction value generation process for generating the correction value including the correction value. In the correction process, the correction processing unit generates the second measurement value data having a value with the lowest digit equal to the lowest digit in the correction value.

  The measuring apparatus according to claim 2 is the measuring apparatus according to claim 1, wherein the signal processing unit has Ma digits (Ma is a natural number) corresponding to the integer part in the measurement result. The first measurement value data can be output as an integer value of (Ma + Mb) digits in which the digit corresponding to the decimal part is Mb digits (Mb is a natural number), and the second calculation processing unit generates the correction value In the processing, a value obtained by converting a value in which the integer part is La digits (La is a natural number less than or equal to Ma) and the decimal part is Lb digits (Lb is (Mb + N)) into an integer value of (La + Lb) digits is the correction value. The correction processing unit corrects the converted measurement value obtained by converting the value of the first measurement value data into an integer value of (Ma + Lb) digits based on the correction value in the correction processing (Ma + Lb). ) The second of the integer value of digits Constant value data is generated, the first calculation processing unit generates the third measurement value data of an integer value in the first calculation processing, and the second calculation processing unit is configured to output the third measurement value data in the measurement result output processing. After converting the value of the third measurement value data into a measurement value A consisting of an integer part of Mc digits (Mc is a natural number greater than or equal to Ma) and a decimal part of Lb digits according to a predetermined conversion procedure, the measurement value A is targeted The process A for generating the fourth measurement value data by executing the second calculation process and the measurement value Ba generated by executing the second calculation process for the value of the third measurement value data Is converted into a measurement value Bb composed of an integer part of Ma digits and a decimal part of Lb digits according to a predetermined conversion procedure, and one of the process B for generating the fourth measurement value data is executed.

  In the measurement apparatus according to claim 1, the second arithmetic processing unit is a first unit that targets a predetermined number of first measurement value data output from the signal processing unit in a state where the correction value acquisition signal is input. Based on either one of the third measurement value data generated by the arithmetic processing and the predetermined number of first measurement value data, a lower order than the lowest digit in the value of the first measurement value data A correction value generation process for generating a correction value including an N-digit value is configured to be executable, and in the second calculation process, a fourth measurement value having a value in which the lowest digit is equal to the lowest digit in the correction value Data is generated, and the correction processing unit generates second measurement value data in which the lowest digit is equal to the lowest digit in the correction value in the correction process.

  Therefore, according to the measuring apparatus of the first aspect, the main processing unit is applied to the amount corresponding to the preprocessing of the first measurement value data output from the signal processing unit in the preprocessing unit prior to the arithmetic processing by the main processing unit. Even if the main processing unit is configured without using expensive computing elements with high processing capacity, the main processing unit can display measurement results in parallel with other various processes. The correction value generated by the signal processing unit, the preprocessing unit, and the main processing unit is output from the signal processing unit in the same procedure as in the measurement processing. Highly accurate measurement by generating the N digit value lower than the lowest digit of the measured value data, and correcting the first measured value data using a more accurate correction value in the measurement process Can get the result That.

  In the measuring apparatus according to claim 2, the signal processing unit performs the first measurement with an integer value of (Ma + Mb) digits in which the digit corresponding to the integer part in the measurement result is Ma digits and the digit corresponding to the decimal part is Mb digits. Value data is output, and in the correction value generation process, the second arithmetic processing unit generates, as a correction value, a value obtained by converting a value in which the integer part is La digits and the decimal part is Lb digits into an integer value of (La + Lb) digits. In the correction process, the correction processing unit corrects the converted measurement value obtained by converting the value of the first measurement value data into an integer value of (Ma + Lb) digits based on the correction value, and converts the first value of the integer value of (Ma + Lb) digits. 2 measurement value data is generated, the first calculation processing unit generates integer third measurement value data in the first calculation processing, and the second calculation processing unit generates the third measurement value in the measurement result output processing. The data value is adjusted to Mc digits according to a predefined conversion procedure. A process A for generating a fourth measurement value data by executing a second calculation process on the measurement value A after being converted into a measurement value A consisting of a fractional part and an Lb-digit decimal part, and a value of the third measurement value data The measured value Ba generated by executing the second arithmetic processing for the first is converted into the measured value Bb composed of an integer part of Ma digits and a decimal part of Lb digits according to a predetermined conversion procedure, and the fourth measured value data One of the process B and the process B is generated.

  Therefore, according to the measurement apparatus of the second aspect, since the fourth measurement value data can be acquired without causing the preprocessing unit to execute the decimal point arithmetic process, the processing capability as the preprocessing unit is high and expensive. A highly accurate measurement result can be acquired without employing a calculation element or imposing a large burden on a preprocessing unit configured with a calculation element with low processing capability. Thereby, the manufacturing cost of a measuring device can fully be reduced.

1 is a configuration diagram showing a configuration of a measuring device 1. FIG. It is explanatory drawing for demonstrating the difference of the measurement result by this-application method when a true value is 500.000 ... V, and the conventional method. It is explanatory drawing for demonstrating the difference in the measurement result by this-application method when a true value is 500.000 ... mA and a conventional method.

  Hereinafter, embodiments of a measuring apparatus according to the present invention will be described with reference to the accompanying drawings.

  First, the configuration of the measuring apparatus 1 will be described with reference to the attached drawings.

  The measuring device 1 shown in FIG. 1 is an example of a “measuring device” and includes a signal processing unit 2, a preprocessing unit 3, an operation unit 4, a display unit 5, a storage unit 6, and a main processing unit 7, and is a measurement target. The voltage value, the current value, and the amount of electric power can be measured.

  The signal processing unit 2 is an example of a “signal processing unit”, and includes a voltage measurement circuit 2 a and a current measurement circuit 2 b. The voltage measurement circuit 2a includes an A / D converter (not shown), and is an example of “first measurement value data” by measuring a voltage value between two arbitrary points to be measured (A / D conversion). The voltage value data D1v is output. The current measurement circuit 2b includes an A / D converter (not shown), measures a current value flowing between two arbitrary points to be measured (A / D conversion), and performs other “first measurement value data”. For example, current value data D1a is output. In this example, in order to facilitate the understanding of the “measuring device”, as an example, the voltage measurement circuit 2a has a 7-digit number according to the resolution of the A / D converter and the set measurement conditions. A value obtained by adding a sign of “+” or “−” to an integer value is output as voltage value data D1v, and the current measurement circuit 2b adds a sign of “+” or “−” to a 7-digit integer value. Is output as current value data D1a.

  Specifically, the voltage measurement circuit 2a, as will be described later in the value (voltage value) of the voltage value data D1v, is an integer in the value (voltage value as a measurement result) of the voltage value data D4v generated by the main processing unit 7. The voltage value is represented by a 7-digit integer value so that the total number of digits corresponding to the decimal part in the value of the voltage value data D4v is 7 digits in the value of the voltage value data D1v and the number of digits corresponding to the part. At the same time, the sign of “+” or “−” is added to the voltage value of the 7-digit integer value and output as voltage value data D1v. The current measurement circuit 2b corresponds to an integer part in the value (current value as a measurement result) of the current value data D4a generated by the main processing unit 7, as will be described later in the value (current value) of the current value data D1a. The current value is represented by a 7-digit integer value so that the total number of digits corresponding to the decimal part in the value of the current value data D4a in the value of the current value data D1a is 7 digits. A sign of “+” or “−” is added to the current value of 7-digit integer value and output as current value data D1a.

  More specifically, as an example, the voltage measurement circuit 2a has an example in which the integer value is Ma = 6 digits and the decimal part is Mb = 1 digits when the voltage value is “+ 0000032.3V (+ 12.3V)”. ), A value of “+0000123” obtained by adding “+” to a 7-digit integer value of “0000123” is output as voltage value data D1v. Further, as an example, when the current value is “+0000455.6 mA (+45.6 mA)” (an example in which the integer part has Ma = 6 digits and the decimal part has Mb = 1 digit), the current measurement circuit 2 b has “0000456 A value of “+0000456” obtained by adding “+” to a 7-digit integer value of “” is output as current value data D1a. In the measurement apparatus 1 of this example, a voltage divider or a current divider is connected to the voltage measurement circuit 2a or the current measurement circuit 2b as necessary, as in the conventional power measurement apparatus. The illustration and description of the auxiliary device are omitted.

  The preprocessing unit 3 is an example of a “preprocessing unit”, and includes a correction value storage unit 3a, a correction processing unit 3b, and an arithmetic processing unit 3c. In the measurement apparatus 1 of the present example, as an example, the preprocessing unit 3 is configured with an FPGA, and the correction processing unit 3b and the calculation without the floating point calculation function are provided in order to reduce the consumption of FPGA resources. A processing unit 3c is configured. The correction value storage unit 3a stores correction value data Drv, Dra (an example of “preliminarily generated correction value”) generated by the “correction value generation process” by the main processing unit 7, as will be described later. In this case, at the time when the “correction value generation process” is not executed, the correction value storage unit 3a stores the correction value data Drv, Dra having the value “0” (correction values having the value “0”: “± 000000000000 Is stored as correction value data Drv, Dra). As will be described later, in the “correction value generation process”, the least significant digit in the value of the correction value data Drv is N digits (for example, N = 2 as compared with the least significant digit in the value of the voltage value data D1v. The lowermost digit in the value of the correction value data Drv is N digits (for example, N = 2 as compared with the lowermost digit in the value of the current value data D1a). It is generated including the lower value by (digits).

  The correction processing unit 3b is an example of a “correction processing unit”, and corrects the value of the voltage value data D1v output from the voltage measurement circuit 2a based on the correction value data Drv stored in the correction value storage unit 3a. Then, the voltage value data D2v which is an example of the “second measurement value data” is generated, and the current value data output from the current measurement circuit 2b based on the correction value data Dra stored in the correction value storage unit 3a. A correction process for correcting the value of D1a to generate current value data D2a, which is another example of “second measurement value data”, is executed. In this case, in the correction process, the correction processing unit 3b generates the voltage value data D2v having the lowest digit equal to the lowest digit in the correction value data Drv, and the lowest digit in the correction value data Dra. Current value data D2a having a value equal to the least significant digit is generated.

  Specifically, in the measuring apparatus 1 of this example, as will be described later, the integer part is La = 6 digits, the decimal part is Lb = 3 digits, and (La + Lb) = (6 + 3) = 9 digits. A configuration is adopted in which values converted to numerical values and added with a sign of “+” or “−” are generated as correction value data Drv and Dra. Accordingly, the correction processing unit 3b converts the value of the voltage value data D1v output from the voltage measurement circuit 2a (Ma = 6 digit integer part and Mb = 1 digit decimal part measurement value into a 7 digit integer value). By converting “+” or “−” and adding “00” to N = 2 digits at the end, (Ma + Lb) = (6 + 3) = 9-digit integer value is converted, The measured value after conversion (an example of “measured value after conversion”) is corrected based on the value of the correction value data Drv to obtain an integer value (voltage value) of (Ma + Lb) = 9 digits. "+" Or "-" is added and output as voltage value data D2v.

  In addition, the correction processing unit 3b converts the value of the current value data D1a output from the current measurement circuit 2b (a measurement value composed of an integer part of Ma = 6 digits and a decimal part of Mb = 1 digit into an integer value of 7 digits. By converting “+” or “−” and adding “00” to N = 2 digits at the end, (Ma + Lb) = (6 + 3) = 9-digit integer value is converted, The measured value after conversion (an example of “measured value after conversion”) is corrected based on the value of the correction value data Dra to obtain an integer value (current value) of (Ma + Lb) = 9 digits. "+" Or "-" is added and output as current value data D2a. A series of processing relating to generation of the voltage value data D2v and the current value data D2a will be described in detail later with a specific example.

  The arithmetic processing unit 3c is an example of a “first arithmetic processing unit”, and an arithmetic processing (for example, product-sum arithmetic processing: “predetermined first arithmetic processing”) that targets the voltage value data D2v. ) To generate voltage value data D3v that is an example of “third measured value data” and an arithmetic process (for example, product-sum arithmetic process: “predetermined first Another example of “1 calculation process” is executed to generate current value data D3a which is another example of “third measured value data”. In this case, the arithmetic processing unit 3c adds, for example, the value of the voltage value data D2v in which the sign of “+” or “−” is added to the 9-digit integer value, to the 11-digit integer value “ Voltage value data D3v having a value (voltage value) added with a sign “+” or “−” is generated and output, and a current value obtained by adding a sign “+” or “−” to a nine-digit integer value. By integrating the values of the data D2a, as an example, current value data D3a having a value (current value) obtained by adding a sign of “+” or “−” to an 11-digit integer value is generated and output.

  The operation unit 4 includes various operation switches for setting operating conditions (measurement conditions) of the measuring apparatus 1, and outputs an operation signal corresponding to the switch operation to the main processing unit 7. The display unit 5 displays measurement results (measured voltage value, current value, and electric energy) and the like under the control of the main processing unit 7. The storage unit 6 stores an operation program of the main processing unit 7, voltage value data D4v, current value data D4a, power value data D4e, and the like generated by the main processing unit 7 as will be described later.

  In addition to the function as the “second arithmetic processing unit”, the main processing unit 7 functions as a “storage processing unit” that stores the measurement result in the storage unit 6 or an external storage device (not shown), and the display unit 5 performs the measurement. A function as a “display processing unit” for displaying the result is provided, and the measuring apparatus 1 is comprehensively controlled. Specifically, the main processing unit 7 performs “correction value generation processing” for generating correction value data Drv and Dra, and arithmetic processing (for example, voltage value data as a target for voltage value data D3v and current value data D3a). “Average value calculation process” for calculating the average value of the voltage value data D3v based on the value of D3v, and “Average value” for calculating the average value of the current value data D3a based on the value of the current value data D3a "Calculation process": an example of "second calculation process"), voltage value data D4v (an example of "fourth measurement value data"), current value data D4a (another example of "fourth measurement value data") ) And power value data D4e are generated and stored as measurement results in the storage unit 6 (an example of “output of measurement results”), or the value is displayed on the display unit 5 (“output of measurement results”). Other example) to measure To execute the result output processing.

  More specifically, in the “correction value generation process” for generating the correction value data Drv, as described above, the correction value data Drv whose value is “0” at the start of the process is stored in the correction value storage unit 3a. Therefore, a state in which a correction value acquisition voltage is applied to the voltage measurement circuit 2a in a state where the voltage divider is connected via the voltage divider (“a state in which a correction value acquisition signal is input as an input signal”) In the example, the voltage value data D1v output from the voltage measurement circuit 2a is output from the correction processing unit 3b as the voltage value data D2v without being substantially corrected. In addition, in the arithmetic processing unit 3c, as an example, voltage value data D2v (ie, a voltage for 100 samplings) output by the correction processing unit 3b for 100 samplings (an example where “predetermined number” is “100”). The voltage value data D3v (an example of “third measurement value data generated by the first calculation process for a predetermined number of first measurement value data”) is generated by integrating the values of the value data D1v). Is done.

  Therefore, the main processing unit 7 is based on the voltage value data D3v output from the arithmetic processing unit 3c, and the voltage value data D2v (that is, the voltage output from the voltage measurement circuit 2a in a state where the correction value acquisition voltage is applied) The average value of the value data D1v) is obtained to generate correction value data Drv. At this time, the main processing unit 7 generates correction value data Drv using a value including a value of N = 2 digits lower than the lowest digit in the value of the voltage value data D1v as a correction value. Specifically, the main processing unit 7 converts the value of the integer part La = 6 digits and the decimal part Lb = 3 digits into an integer value of (La + Lb) = (6 + 3) = 9 digits “+”. Alternatively, “−” is added to obtain a correction value. In place of the configuration for obtaining the correction value data Drv by the method as described above, the voltage value data D1v for 100 samples output from the voltage measurement circuit 2a is directly used without executing the integration process by the arithmetic processing unit 3c. It is also possible to employ a configuration in which the correction value data Drv is generated by causing the main processing unit 7 to output and integrating the values of the 100 voltage value data D1v to calculate an average value.

  Further, in the “correction value generation process” for generating the correction value data Dra, as described above, the correction value data Dra whose value is “0” is stored in the correction value storage unit 3a at the start of processing. Another example of a state in which a current for correction value acquisition is supplied to the current measurement circuit 2b in a state where the shunt is connected via the shunt (“state in which a correction value acquisition signal is input as an input signal”) ), The current value data D1a output from the current measurement circuit 2b is output from the correction processing unit 3b as current value data D2a without being substantially corrected. Further, in the arithmetic processing unit 3c, as an example, current value data D2a (ie, current corresponding to 100 samplings) output from the correction processing unit 3b for 100 samplings (an example where “predefined number” is “100”). Current value data D3a (another example of “third measurement value data generated by the first calculation process for a predetermined number of first measurement value data”) by integrating the values of the value data D1a) Is generated.

  Therefore, the main processing unit 7 is based on the current value data D3a output from the arithmetic processing unit 3c, and the current value data D2a (that is, the current output from the current measurement circuit 2b in the state where the current for correction value acquisition is supplied). An average value of the value data D1a) is obtained to generate correction value data Dra. At this time, the main processing unit 7 generates correction value data Dra using a value including a value of N = 2 digits lower than the lowest digit in the value of the current value data D1a as a correction value. Specifically, the main processing unit 7 converts the value of the integer part La = 6 digits and the decimal part Lb = 3 digits into an integer value of (La + Lb) = (6 + 3) = 9 digits “+”. Alternatively, “−” is added to obtain a correction value. In place of the configuration for obtaining the correction value data Dra by the method as described above, the current value data D1a for 100 samples output from the current measurement circuit 2b is directly used without executing the integration process by the arithmetic processing unit 3c. It is also possible to adopt a configuration in which the main processing unit 7 outputs the correction value data Dra by causing the main processing unit 7 to calculate the average value by integrating the values of the 100 current value data D1a.

  Further, in the second calculation process in the measurement result output process described above, the main processing unit 7 has the voltage value data D4v and current value data D4a having the lowest digit equal to the lowest digit in the correction value data Drv and Dra. And power value data D4e. In this case, the main processing unit 7 executes one of “Processing A” and “Processing B” that is designated in advance in the above-described measurement result output processing.

  Specifically, as the “process A”, the value of the voltage value data D3v (the integrated value of the voltage values for 100 samplings) is converted into an integer part of Mc = 8 digits and Lb = After converting to a voltage value consisting of a three-digit decimal part (average value of voltage values calculated based on voltage value data D3v: an example of “measurement value A”), the “second calculation process for the measurement value” ”To generate the voltage value data D4v, and the value of the current value data D3a (the integrated value of the current values for 100 samplings) according to a predefined conversion procedure, Mc = 8-digit integer part, and Lb = After converting to a current value consisting of a decimal part of 3 digits (an average value of current values calculated based on the current value data D3a: another example of “measured value A”), the measured value is targeted as “ Execute the 2nd calculation process ” To generate a D4a.

  In addition, as the “process B”, the measurement value (the voltage value data D3v is generated by executing the “second arithmetic process” for the value of the voltage value data D3v (the integrated value of the voltage values corresponding to 100 samplings). An average value of voltage values calculated based on the above: an example of “measurement value Ba” is measured according to a predetermined conversion procedure, and is a measurement value consisting of an integer part of Ma = 6 digits and a decimal part of Lb = 3 digits (“ An example of “measured value Bb”) is generated to generate voltage value data D4v, and “second arithmetic processing” is performed on the value of current value data D3a (the integrated value of current values for 100 samplings). Measured value (average value of current values calculated based on current value data D3a: another example of “measured value Ba”), Ma = 6-digit integer part according to a predetermined conversion procedure, and Lb = measured value consisting of a decimal part of 3 digits ( Further, the main processing unit 7 converts the electric power amount into the current value data D4v and the current value data D4a based on the generated voltage value data D4v and the current value data D4a. The power value data D4e is generated by calculation.

  Next, a method for measuring a voltage value, a current value, and an electric energy by the measuring apparatus 1 will be described with reference to the attached drawings. In the following description, an example in which measurement processing is performed in a state where a voltage divider is connected to the voltage measurement circuit 2a and a current divider is connected to the current measurement circuit 2b will be described. What is necessary is just to connect to the signal processing part 2 as needed, and a series of measurement processes can also be performed without using a voltage divider or a current divider.

  In measurement processing using a voltage divider or a current divider, first, “correction value generation processing” for generating correction value data Drv and Dra is executed. Specifically, when generating the correction value data Drv, as an example, the voltage measurement circuit 2a in a state where the voltage divider is connected to the voltage measurement circuit 2a via the voltage divider (for example, a voltage generation not shown) (+ 100.000V output from the device) and the operation unit 4 is operated to input an accurate value of the voltage to be applied (in this example, “100.000V”), and then an instruction to start processing is given. To do. At this time, as described above, the voltage measurement circuit 2a in the measurement apparatus 1 of the present example replaces the voltage value in which the integer part is Ma = 6 digits and the decimal part is Mb = 1 digit with a 7-digit integer value. A value (voltage value) with “+” or “−” added thereto is output as voltage value data D1v. For this reason, a voltage of “+100.000 V” is applied when a negative offset component (for example, “−10.336... V”) inherent to the voltage divider connected to the voltage measurement circuit 2 a exists. In this state, as an example, voltage value data D1v (voltage value data D1v indicating a voltage value of 89.6 V) having a value “+00000008” or voltage value data D1v (89.89) having a value “+00000008” is obtained. Voltage value data D1v) indicating a voltage value of 7V is output from the voltage measurement circuit 2a.

  Further, in the measurement apparatus 1 of this example, at the start of the “correction value generation process”, as described above, the correction value storage unit 3a stores the correction value data Drv (“± 000000000000” having a value “0”). Value correction value data Drv) is stored. Accordingly, the voltage value data D1v is not substantially corrected by the correction processing unit 3b, and the voltage value data D2v having a value of “+000089600” (voltage value data D2v indicating a voltage value of 89.600 V) or , Voltage value data D2v having a value of “+000089700” (voltage value data D1v indicating a voltage value of 89.700 V) is output from the correction processing unit 3b.

  Further, in the arithmetic processing unit 3c, the voltage value data D3v is generated by integrating the values of the voltage value data D2v (100 pieces of voltage value data D2v) for 100 samplings output from the correction processing unit 3b. At this time, 36 of the 100 voltage value data D1v output from the voltage measurement circuit 2a have a value of “+0000966”, and 64 of the 100 voltage value data D1v have “+0000897”. Of the 100 voltage value data D2v output from the correction processing unit 3b is a value of “+000089600” and 64 of the 100 voltage value data D2v are “ +000089700 ". As a result, in the above example, voltage value data D3v (voltage value data D3v indicating a voltage value of 8966.400V) having a value of “+00008966400” is generated in the arithmetic processing unit 3c.

  Therefore, the main processing unit 7 calculates the average value of the voltage value data D2v based on the voltage value data D3v output from the arithmetic processing unit 3c, and generates correction value data Drv. Specifically, first, based on the value (8966.400V) of “+00008966400”, the average value of 100 voltage value data D2v is calculated to be the value (89.664V) of “+00000008664”. Next, based on the fact that the value of the voltage value input to the voltage measurement circuit 2a via the voltage divider is “+000100000” (100.000V), the correction value data Drv ((La + Lb) of the value “−000010336”. ) = Correction value data Drv) indicating a correction value of “+ 10.336V”, which is an example of a correction value composed of a nine-digit integer value and a sign of “+” or “−”. Further, the main processing unit 7 stores the generated correction value data Drv in the correction value storage unit 3a. Thereby, the generation of the correction value data Drv of the correction value for the value including the value of N = 2 digits lower than the lowest digit in the value of the voltage value data D1v is completed.

  Further, when generating the correction value data Dra, as an example, a current for correction value acquisition (output from a current output device (not shown) as an example) through the shunt to the current measurement circuit 2b in a state where the shunt is connected. The current value of +100.000 mA is supplied, and the operation unit 4 is operated to input an accurate value of the supplied current (in this example, “100.000 mA”), and then an instruction to start processing is given. At this time, as described above, the current measurement circuit 2b in the measurement apparatus 1 of this example replaces the current value in which the integer part is Ma = 6 digits and the decimal part is Mb = 1 digit with a 7-digit integer value. A value (current value) with “+” or “−” added thereto is output as current value data D1a. Therefore, when a plus offset component (for example, “+10.336... MA”) unique to the shunt connected to the current measurement circuit 2b exists, a current of “+100.000 mA” is supplied. In this state, as an example, current value data D1a (current value data D1a indicating a current value of 110.3 mA) with a value of “+0001103” or current value data D1a (110.4 mA of a value of “+0001104”) Current value data D1a) indicating the current value of the current is output from the current measurement circuit 2b.

  Further, in the measuring apparatus 1 of this example, at the time of starting the “correction value generation process”, as described above, the correction value storage unit 3a stores the correction value data Dra (“± 000000000”) having the value “0”. Value correction value data Dra) is stored. Accordingly, the current value data D1a is not substantially corrected by the correction processing unit 3b, and the current value data D2a having a value of “+000110300” (current value data D2a indicating a current value of 110.300 mA) or , Current value data D2a having a value of “+000110400” (current value data D1a indicating a current value of 110.400 mA) is output from the correction processing unit 3b.

  Furthermore, in the arithmetic processing unit 3c, the current value data D3a is generated by integrating the values of the current value data D2a (100 pieces of current value data D2a) for 100 samplings output from the correction processing unit 3b. At this time, 64 of the 100 current value data D1a output from the current measurement circuit 2b are “+0001103”, and 36 of the 100 current value data D1a are “+0001104”. Of the 100 current value data D2a output from the correction processing unit 3b is a value of “+000110300”, and 36 of the 100 current value data D2a are “ +000110400 ". As a result, in the above example, current value data D3a (current value data D3a indicating a current value of 11033.600 mA) having a value of “+00011033600” is generated in the arithmetic processing unit 3c.

  Therefore, the main processing unit 7 calculates the average value of the current value data D2a based on the current value data D3a output from the arithmetic processing unit 3c, and generates correction value data Dra. Specifically, first, based on the value (11033.600 mA) of “+00011033600” of the current value data D3a, the average value of 100 current value data D2a is a value (110.336 mA) of “+000110336”. And calculate. Next, based on the fact that the value of the current value input to the current measurement circuit 2b via the shunt is “+000100,000” (100.000 mA), the correction value data Dra ((La + Lb) of the value “+000010336” = Correction value data Dra) indicating a correction value of “−10.336 mA”, which is an example of a correction value made up of an integer value of 9 digits and a sign of “+” or “−”. Further, the main processing unit 7 stores the generated correction value data Dra in the correction value storage unit 3a. Thereby, the generation of the correction value data Dra of the correction value for the value including the value of N = 2 digits lower than the lowest digit in the value of the current value data D1a is completed.

  On the other hand, when measuring the voltage value, current value, and electric energy of the measurement object, the voltage measurement circuit 2a is connected to the measurement object via the voltage divider, and the current measurement circuit 2b is connected via the current divider. Connect to the measurement target. Next, the operation unit 4 is operated to instruct the start of the measurement process. Actually, the voltage value measurement process, the current value measurement process, and the power amount measurement process are executed in parallel. In order to facilitate understanding of the operating principle of the measurement apparatus 1, the voltage value The measurement process and the current value measurement process will be described separately. Further, since a method for determining the amount of electric power based on the voltage value and the current value as a measurement result (method for measuring the electric energy) is well known, detailed description thereof is omitted.

  When a voltage (potential difference) is generated between any two points to be measured connected to the voltage measurement circuit 2a via a voltage divider, the voltage measurement circuit 2a first measures this voltage (A / D Voltage value data D1v is generated by conversion. At this time, as shown in FIG. 2, for example, the true value of the voltage generated in the measurement object (hereinafter also referred to as “true value”) is “500.000... V”, and the voltage The voltage value that decreases due to the negative offset component inherent to the voltage divider connected to the measurement circuit 2a is the value of the correction value data Drv acquired by the above “correction value generation process” (in this example, “+ 10.336V ”), Which is approximately the same as the reciprocal of (“ 10.336... V ”in this example), the voltage value (applied) input (applied) to the voltage measuring circuit 2a via the voltage divider. (Hereinafter also referred to as “input value”) is “489.664... V”. Therefore, in this example, the voltage value data D1v (voltage value data D1v indicating a voltage value of 489.6V) having a value of “+0004896” and the voltage value data D1v (voltage of 489.7V) having a value of “+0004897” are used. Voltage value data D1v) indicating a value is sequentially output from the voltage measurement circuit 2a.

  In the figure, the actual values of the correction value data Drv and the voltage value data D1v to D3v are shown in parentheses. At this time, voltage value data D1v having a value of “+0004896” (a value obtained by truncating the lower digit in the input value to the voltage measuring circuit 2a) and a value of “+0004897” (to the voltage measuring circuit 2a) The voltage value data D1v having a value of “+000096” output from the voltage measurement circuit 2a when the correction value data Drv is generated as described above is a ratio of the value obtained by rounding up the lower digits of the input value to the voltage value data D1v. And the voltage value data D1v having a value of “+0000897”. Accordingly, in this example, 36 of the 100 voltage value data D1v have a value of “+0004896”, and 64 of the 100 voltage value data D1v have a value of “+0004897”.

  Further, by the “correction value generation process” executed prior to this measurement process, the correction value storage unit 3a stores the correction value data Drv (+ 10.336V) indicating the correction value data “+000010336”. Drv) is stored. Therefore, when the voltage value data D1v having the value “+0004896” is output from the voltage measurement circuit 2a, the correction processing unit 3b matches this value with the number of digits of the value (correction value) of the correction value data Drv. After setting “+000489600”, the value of the correction value data Drv stored in the correction value storage unit 3a is added to obtain voltage value data D2v (a voltage value of 499.936V) of “+000499936”. Voltage value data D2v) is generated (an example of “correction processing”). When the voltage value data D1v having the value “+0004897” is output from the voltage measurement circuit 2a, the correction processing unit 3b matches this value with the number of digits of the value (correction value) of the correction value data Drv. After setting “+000489700”, the value of the correction value data Drv stored in the correction value storage unit 3a is added to obtain the voltage value data D2v (a voltage value of 500.036V) of “+000500036”. Voltage value data D2v) is generated (another example of “correction processing”).

  Further, the arithmetic processing unit 3c integrates the values of the voltage value data D2v for 100 samples output from the correction processing unit 3b to generate the voltage value data D3v. At this time, 36 of the 100 voltage value data D2v output from the correction processing unit 3b are “+000499936” and 64 of the 100 voltage value data D2v are “+000500036”. Therefore, the arithmetic processing unit 3c integrates the values of the 100 voltage value data D2v to obtain the voltage value data D3v having a value of “+00000050000000” (voltage value data D3v indicating a voltage value of 50,000.000V). ) And output to the main processing unit 7.

  On the other hand, the main processing unit 7 determines the average value of the voltage value data D2v based on the voltage value data D3v output from the arithmetic processing unit 3c, and generates the voltage value data D4v. Specifically, as an example, when “Processing A” of “Processing A” and “Processing B” is selected, first, the value of “+000000000000” of the voltage value data D3v (50000.000V) is converted into a value (measurement value A) of “+ 00050000000.000V” consisting of an integer part of Mc = 8 digits and a decimal part of Lb = 3 digits. Next, based on the converted value, the average value of the 100 voltage value data D2v is calculated to be a value of “+ 000500.000V”. Subsequently, the calculation result is stored in the storage unit 6 as voltage value data D4v, and the value is displayed on the display unit 5. Thereby, the “measurement result output process” regarding the voltage value to be measured is completed.

  In this case, as shown in FIG. 2, in the measurement apparatus 1 of the present example, in the above example where the true value of the voltage generated in the measurement target is “500.000. Voltage value data D4v having a value of “+ 500.000V” is generated, and a difference value (error) between the true value and the measurement result is “0.000V”. On the other hand, as in the conventional power measurement device, the lowest digit in the value of the correction value data Drv is made equal to the lowest digit in the value of the voltage value data D1v output from the voltage measurement circuit 2a. When the measurement process of the voltage value similar to the above example is executed by the measurement apparatus configured to execute each process, as shown in the figure, the voltage value of the value “+ 499.964V” is obtained as the measurement result. Data D4v is generated, and the difference value (error) between the true value and the measurement result is “−0.036 V”. Therefore, in this example, the true value is measured by the amount corresponding to the correction of the voltage value data D1v using the correction value data Drv including N = 2 digits lower than the lowest digit in the value of the voltage value data D1v. It can be seen that the difference value (error) from the result is small.

  On the other hand, when the current is conducted between any two points to be measured connected to the current measurement circuit 2b via the shunt, first, the current measurement circuit 2b measures this current (A / D Current value data D1a is generated after conversion. At this time, as shown in FIG. 3, for example, the true value (hereinafter also referred to as “true value”) of the current passing through the measurement target is “500.000... MA”, and The current value that increases due to the plus offset component inherent to the shunt connected to the current measurement circuit 2b is the value of the correction value data Dra acquired by the above “correction value generation process” (in this example, “−10 .336 mA ”) (in this example,“ +10.336... MA ”), the value of the current input to the current measurement circuit 2b via the shunt (hereinafter referred to as“ input ”). Value ”) is“ 510.336... MA ”. Therefore, in this example, the current value data D1a having a value of “+0005103” (current value data D1a indicating a current value of 510.3 mA) and the current value data D1a having a value of “+0005104” (current of 500.4 mA) Current value data D1a) indicating the value is sequentially output from the current measurement circuit 2b.

  In the figure, the actual values of the correction value data Dra and the current value data D1a to D3a are shown in parentheses. At this time, current value data D1a having a value of “+0005103” (a value obtained by truncating the lower digit in the input value to the current measuring circuit 2b) and a value of “+0005104” (to the current measuring circuit 2b) The current value data D1a having a value of “+0001103” that is output from the current measurement circuit 2b when the correction value data Dra is generated as described above is a ratio of the input value to the current value data D1a. And the current value data D1a having a value of “+0001104”. Therefore, in this example, 64 of the 100 current value data D1a have a value of “+0005103”, and 36 of the 100 current value data D1a have a value of “+0005104”.

  Further, by the “correction value generation process” executed prior to the measurement process, the correction value storage unit 3a stores the correction value data Dra (−10.336 mA indicating a correction value with a value of “−000010336”. Value data Dra) is stored. Therefore, when the current value data D1a having the value “+0005103” is output from the current measurement circuit 2b, the correction processing unit 3b matches this value with the number of digits of the value (correction value) of the correction value data Dra. By adding “+000510300” and adding the value of the correction value data Dra stored in the correction value storage unit 3a, the current value data D2a having a value of “+0004999964” (indicating a current value of 499.964 mA) Current value data D2a) is generated (an example of “correction processing”). When the current value data D1a having the value “+0005104” is output from the current measurement circuit 2b, the correction processing unit 3b matches this value with the number of digits of the correction value data Dra (correction value). After setting “+000510400”, the value of the correction value data Dra stored in the correction value storage unit 3a is added to obtain the current value data D2a (showing a current value of 500.064 mA) of “+000500064”. Current value data D2a) is generated (another example of “correction process”).

  Further, the arithmetic processing unit 3c integrates the values of the current value data D2a for 100 samples output from the correction processing unit 3b to generate current value data D3a. At this time, 64 of the 100 current value data D2a output from the correction processing unit 3b have a value of “+0004999964”, and 36 of the 100 current value data D2a have “+000500064”. Therefore, the arithmetic processing unit 3c integrates the values of the 100 current value data D2a to obtain current value data D3a having a value of “+000000000000” (current value data D3a indicating a current value of 50,000.000 mA). ) And output to the main processing unit 7.

  On the other hand, the main processing unit 7 determines the average value of the current value data D2a based on the current value data D3a output from the arithmetic processing unit 3c, and generates the current value data D4a. Specifically, as an example, when “Process B” of “Process A” and “Process B” is selected, first, the value of “+000000000000” of the current value data D3a Based on (50,000.000 mA), the average value of 100 pieces of current value data D2a is calculated to be a value of “+000500,000” (an example of “500.000 mA:“ measured value Ba ”). Next, the calculated value is converted into a value (measurement value Bb) of “+000500.000 mA” composed of an integer part of Ma = 6 digits and a decimal part of Lb = 3 digits. Subsequently, the converted current value is stored in the storage unit 6 as the current value data D4a, and the value is displayed on the display unit 5. Thereby, the “measurement result output process” regarding the current value to be measured is completed.

  Further, the main control unit 7 calculates the power value consumed by the measurement object based on the value of the voltage value data D4v and the value of the current value data D4a calculated by the above two measurement processes, and the calculation result is obtained. The power value data D4e is stored in the storage unit 6 and the value is displayed on the display unit 5. Thereby, the “measurement result output process” regarding the power value is completed.

  In this case, as shown in FIG. 3, in the measurement apparatus 1 of this example, in the above example where the true value of the current conducting the measurement target is “500.000... Current value data D4a having a value of “+500.000 mA” is generated, and a difference value (error) between the true value and the measurement result is “0.000 mA”. On the other hand, like the conventional power measuring apparatus, the lowest digit in the value of the correction value data Dra is made equal to the lowest digit in the value of the current value data D1a output from the current measurement circuit 2b. When the current value measurement process similar to that in the above example is executed by the measurement apparatus configured to execute each process, the current value having a value of “+500.036 mA” as the measurement result is shown in FIG. Data D4a is generated, and the difference value (error) between the true value and the measurement result is “+0.036 mA”. Therefore, in this example, the true value is measured by the amount corresponding to the correction of the current value data D1a using the correction value data Dra including N = 2 digits lower than the lowest digit in the value of the current value data D1a. It can be seen that the difference value (error) from the result is small.

  As described above, in the measurement apparatus 1, the main processing unit 7 targets the voltage value data D1v and current value data D1a for 100 samples output from the signal processing unit 2 in a state where a correction value acquisition signal is input. Based on one of the voltage value data D3v and the current value data D3a generated by the “first arithmetic processing” and the voltage value data D1v and the current value data D1a for 100 samplings, the voltage value data The “correction value generation process” for generating correction value data Drv and Dra of values including N = 2 digits lower than the lowest digit in the values of D1v and current value data D1a is configured to be executable. , In the “second calculation process”, the voltage value data having a value in which the least significant digit is equal to the least significant digit in the values (correction values) of the correction value data Drv and Dra. Voltage D4v and current value data D4a, and the correction processing unit 3b generates a voltage having a value in which the least significant digit is equal to the least significant digit in the values (correction values) of the correction value data Drv and Dra in the “correction processing”. Value data D2v and current value data D2a are generated.

  Therefore, according to this measuring apparatus 1, the main value of the voltage value data D1v and current value data D1a output from the signal processing unit 2 in the preprocessing unit 3 is preprocessed by the main processing unit 7 prior to the arithmetic processing. The burden on the processing unit 7 can be reduced, and even if the main processing unit 7 is configured without adopting an expensive arithmetic element with high processing capability, the main processing unit 7 can perform other various processes. In addition to smoothly displaying and recording the measurement results in parallel, the correction values generated by the signal processing unit 2, the preprocessing unit 3 and the main processing unit 7 in the same procedure as in the measurement processing ( Correction value data Drv, Dra) are generated including values of N = 2 digits lower than the lowest digit of the voltage value data D1v and current value data D1a output from the signal processing unit 2, and in the measurement process ,Than By the amount of correcting the voltage value data D1v and current value data D1a with accurate correction value, it is possible to obtain highly accurate measurement results.

  Further, in this measuring apparatus 1, the signal processing unit 2 is configured such that the digit corresponding to the integer part in the value (measurement result) of the voltage value data D4v and the current value data D4a is Ma = 6 digits and the digit corresponding to the decimal part is Mb. = Voltage value data D1v and current value data D1a having a value obtained by adding "+" or "-" to a 7-digit integer value of 1 digit (Ma + Mb), and the main processing unit 7 performs "correction value generation processing" The correction value data Drv and Dra are generated by correcting the value obtained by converting the value of the integer part La = 6 digits and the decimal part Lb = 3 digits into an integer value of (La + Lb) = 9 digits as a “correction value”, and correcting it. In the “correction process”, the processing unit 3b converts the values of the voltage value data D1v and the current value data D1a into (Ma + Lb) = 9-digit integer values, and converts the converted measurement values to the values of the correction value data Drv and Dra ( Corrected based on (correction value) (Ma Lb) = 9-digit integer value obtained by adding “+” or “−” to the voltage value data D2v and current value data D2a, and the arithmetic processing unit 3c uses the integer value in the “first arithmetic processing”. Voltage value data D3v and current value data D3a are generated, and in the “measurement result output process”, the main processing unit 7 sets the values of the voltage value data D3v and the current value data D3a to Mc = 11 according to a predetermined conversion procedure. The voltage value data D4v and the current value data are obtained by executing the “second calculation process” on the “measurement value A” after the conversion to the “measurement value A” consisting of the integer part of the digit and the decimal part of Lb = 3 digits. "Measurement value Ba" generated by executing "Processing A" for generating D4a and "Second calculation processing" for the values of voltage value data D3v and current value data D3a according to a predetermined conversion procedure Either “processing B” for generating voltage value data D4v and current value data D4a by converting into “measurement value Bb” consisting of an integer part of a = 6 digits and a decimal part of Lb = 3 digits is executed. .

  Therefore, according to the measuring apparatus 1, the voltage value data D4v and the current value data D4a can be acquired without causing the preprocessing unit 3 to execute the decimal point calculation process. High-precision measurement results (voltage value data D4v and current value data D4a) without using a high-priced arithmetic element or imposing a heavy burden on a “pre-processing unit” configured with a computer element with low processing capability ) Can be obtained. Thereby, the manufacturing cost of the measuring apparatus 1 can be reduced sufficiently.

  The configuration of the “measuring device” is not limited to the configuration of the measuring device 1 described above. For example, the measurement apparatus 1 having the preprocessing unit 3 (correction value storage unit 3a, correction processing unit 3b, and arithmetic processing unit 3c) configured with an FPGA has been described as an example. It is not limited to what was comprised by, It can also comprise by DSP and CPU. Even in such a configuration, a “pre-processing unit” is configured by adopting a DSP that does not have a floating-point arithmetic function or a CPU that does not have a floating-point arithmetic function, thereby having a pre-processing unit 3 configured by FPGA. Similar to the measurement apparatus 1, the manufacturing cost of the “measurement apparatus” can be sufficiently reduced as compared with a configuration in which various calculations are performed by a high-performance CPU without providing a “preprocessing unit”.

DESCRIPTION OF SYMBOLS 1 Measuring apparatus 2 Signal processing part 2a Voltage measurement circuit 2b Current measurement circuit 3 Preprocessing part 3a Correction value storage part 3b Correction processing part 3c Operation processing part 4 Operation part 5 Display part 6 Storage part 7 Main processing part D1a-D4a Current value Data D1v to D4v Voltage value data D4e Power value data Dra, Drv Correction value data

Claims (2)

A signal processing unit for A / D converting an input signal to be measured and outputting first measurement value data;
A correction processing unit that executes a correction process for generating the second measurement value data by correcting the value of the first measurement value data based on the correction value generated in advance, and preliminarily defined for the second measurement value data A pre-processing unit having a first calculation processing unit for executing the first calculation processing and generating third measurement value data;
A second calculation processing unit configured to generate a fourth measurement value data by executing a second calculation process defined in advance for the third measurement value data, and the generated fourth measurement value data is input to the input signal; A main processing unit for executing a measurement result output process for outputting as a measurement result with respect to
The second arithmetic processing unit targets the first measured value data of a predetermined number output from the signal processing unit in a state where a correction value acquisition signal as the input signal is input. Based on one of the third measurement value data generated by the arithmetic processing and the predetermined number of first measurement value data, the least significant digit in the value of the first measurement value data The correction value generation process for generating the correction value including the value of the lower N digits (N is a natural number) is executable, and in the second calculation process, the lowest digit is the correction value. Generating the fourth measured value data having a value equal to the least significant digit,
In the correction process, the correction processing unit generates the second measurement value data in which the lowest digit is equal to the lowest digit in the correction value. In the signal processing unit, the digit corresponding to the integer part in the measurement result is Ma digit (Ma is a natural number) and the digit corresponding to the decimal part in the measurement result is Mb digit (Mb is a natural number) (Ma + Mb). The first measured value data can be output as an integer value of digits,
In the correction value generation process, the second arithmetic processing unit calculates a value in which the integer part is La digits (La is a natural number less than or equal to Ma) and the decimal part is Lb digits (Lb is (Mb + N)) (La + Lb) A value converted into a digit integer value is generated as the correction value,
In the correction process, the correction processing unit corrects the converted measurement value obtained by converting the value of the first measurement value data into an integer value of (Ma + Lb) digits based on the correction value, and adjusts the value of (Ma + Lb) digits. Generating the second measured value data of a numerical value;
The first calculation processing unit generates the third measurement value data of an integer value in the first calculation processing,
In the measurement result output process, the second arithmetic processing unit is configured to convert the value of the third measurement value data into an integer part of Mc digits (Mc is a natural number greater than or equal to Ma) and a decimal number of Lb digits according to a predetermined conversion procedure. A process A for generating the fourth measurement value data by executing the second calculation process on the measurement value A after being converted into the measurement value A comprising a unit, and the value of the third measurement value data The measured value Ba generated by executing the second arithmetic processing is converted into a measured value Bb composed of an integer part of Ma digits and a decimal part of Lb digits according to a predetermined conversion procedure, and the fourth measured value data The measurement apparatus according to claim 1, wherein one of the process B and the process B is generated.

Images