JP2017073882A - Power conversion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To execute an operation of a power conversion circuit by using three of four sensors of a power conversion device that are used in normal control.SOLUTION: A power conversion device comprises: a power conversion circuit; an input voltage measurement unit; an input current measurement unit; an output voltage measurement unit; an output current measurement unit; a calculation unit that calculates a power conversion efficiency from measurement values of four measurement units, and stores history data in which the measurement values and the power conversion efficiency are associated with each other; a determination unit that determines presence or absence of failures of the four measurement units; and a controller that performs power conversion control of the power conversion circuit. In a case where one of the four measurement units goes wrong, the calculation unit calculates an estimation value of the power conversion efficiency on the basis of the measurement values of three normal measurement units. The controller estimates the measurement value of the one measurement unit that is in failure by using the measurement values of the three normal measurement units and the estimation value of the power conversion efficiency, and continues the power conversion control.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power conversion device, and in particular, an input voltage sensor that measures an input voltage, an input current sensor that measures an input current to a power conversion circuit, an output voltage sensor that measures an output voltage, and a power conversion circuit It is related with the power converter device which can be drive | operated even if any one of the output current sensors which measure the output current from a failure or delete any one.

  Conventionally, some have a configuration in which a plurality of power conversion circuits are provided in order to continue the operation of the power conversion device even if the power conversion circuit fails. With such a configuration, even when some of the power conversion circuits fail, the operation can be continued using only normal power conversion circuits (see, for example, Patent Document 1).

JP-A-9-275699

However, the prior art has the following problems.
When a plurality of power conversion circuits are provided, the circuit becomes complicated and large-scaled, resulting in an increase in cost and an increase in the size of the power conversion device. In addition, when switching from a failed power conversion circuit to a normal power conversion circuit, there is a problem that complicated control must be performed so that the normal power conversion circuit does not fall into an overcurrent state.

  The present invention has been made to solve the above-described problems, and it is not necessary to perform complicated control or to provide a plurality of power conversion circuits. The power conversion device used for normal control is provided. An object of the present invention is to obtain a power conversion device that can execute the operation of the power conversion circuit by using three of the total four sensors of the input and output voltage sensors and current sensors.

  A power conversion device according to the present invention includes a power conversion circuit that converts an input voltage into a desired output voltage, an input voltage measurement device that measures the input voltage, an input current measurement device that measures an input current to the power conversion circuit, and It consists of an output voltage measuring instrument that measures the output voltage, an output current measuring instrument that measures the output current from the power conversion circuit, an input voltage measuring instrument, an input current measuring instrument, an output voltage measuring instrument, and an output current measuring instrument A calculation unit that calculates the power conversion efficiency in the power conversion circuit from the measured values of the four measuring devices, and stores history data in which the measured values of the four measuring devices and the power conversion efficiency are associated with each other in the storage unit; A determination unit that determines the presence or absence of a failure of the four measuring devices based on the measurement values of the four measuring devices, and a control unit that performs power conversion control of the power conversion circuit; Of the four measuring instruments When the determination result indicating that one measuring device has failed is received, the estimated value of the power conversion efficiency is calculated based on the measured values of three measuring devices that are normal among the four measuring devices. When the determination unit receives a determination result indicating that one of the four measuring devices has failed, the measurement value of three measuring devices that are normal among the four measuring devices, and the arithmetic unit Is used to estimate the measured value of one measuring device that has failed and to continue the power conversion control.

  The power conversion device according to the present invention is based on the detection values of the three sensors when one of the four sensors fails or when one of the four sensors is deleted. The configuration is such that the detection value of the remaining one sensor can be estimated. As a result, it is not necessary to perform complicated control or to provide a plurality of power conversion circuits. Of the total of four sensors, that is, the voltage sensor and the current sensor of the input / output of the power conversion device used for normal control. By using three sensors, it is possible to obtain a power conversion device that can execute the operation of the power conversion circuit.

It is a figure which shows an example of a structure of the power converter device in Embodiment 1, 2 of this invention. It is a figure which shows an example of a structure of the power converter device in Embodiment 3 of this invention.

  Hereinafter, a power converter according to the present invention will be described with reference to the drawings according to each embodiment. In each embodiment, the same or corresponding parts are denoted by the same reference numerals, and redundant description is omitted.

Embodiment 1 FIG.
FIG. 1 is a diagram showing an example of a configuration of a power conversion device according to Embodiment 1 of the present invention. In FIG. 1, a power conversion device 100 includes a power conversion circuit 3, a failure determination unit 6, a calculation unit 7, a control unit 8, an input voltage sensor 1, an input current sensor 2, an output voltage sensor 9, and an output current sensor 10. Configured. A power source 11 (shown as an AC power source in FIG. 1) is connected to the input side, and an output load 12 is connected to the output side.

  An input voltage sensor 1 that detects an input voltage value V1 is inserted between input terminals of the power conversion device 100, and an input current that detects an input current value I1 is interposed between one of the input terminals and the power conversion circuit 3. Sensor 2 is inserted.

  Further, an output voltage sensor for detecting the output voltage value V2 is inserted between the output terminals of the power conversion device 100, and an output for detecting the output current value I2 is provided between one of the output terminals and the power conversion circuit 3. A current sensor 10 is inserted.

  The failure determination unit 6 determines whether or not each of the sensors 1, 2, 9, and 10 is in failure, and transmits the determination result to the calculation unit 7 and the control unit 8.

  When the determination result received from the failure determination unit 6 is “normal” for all the sensors, the calculation unit 7 detects the input voltage value V1 and the input current detected by the sensors 1, 2, 9, and 10 as the measurement unit. Power conversion efficiency is calculated by performing a predetermined calculation according to the value I1, the output voltage value V2, and the output current value I2, and the calculation result is stored as history data in a storage unit (not shown).

  And the control part 8 controls the power converter circuit 3 by performing switching control of the power element in the power converter circuit 3, and makes the power supply 11 become a desired output voltage or a desired output current, or both. And supplied to the output load 12.

  Here, for example, the conversion from the detection value of the input voltage sensor 1 to the input voltage value V1 is usually performed by converting an analog value detected by the sensor into a digital value by an A / D (Analog-to-Digital) converter. This is performed by converting and converting to the input voltage value V1 by a predetermined conversion formula.

  In addition, the conversion to the input voltage value V1 including the A / D converter, the calculation and storage in the calculation unit 7, and the control in the control unit 8 are usually performed by one MPU (Micro-Processing Unit). . For example, an A / D converter (not shown) that performs A / D conversion of analog signals from the sensors 1, 2, 9, and 10, a failure determination unit 6, a calculation unit 7, and a control unit 8 are included in one MPU. It is configured.

  The power conversion circuit 3 includes a power element 4 such as a diode, a MOS (Metal Oxide Semiconductor), or an IGBT (Insulated Gate Bipolar Transistor), and a magnetic component 5 such as a reactor or a transformer. Since the power element 4 or the magnetic component 5 generates a large amount of heat due to power loss and leads to the worst thermal destruction, it is cooled by a cooler (not shown).

The power conversion efficiency of the power conversion device 100 is obtained by dividing the output power by the input power, and can be expressed by the following equation (1).
Power conversion efficiency E = (V2 × I2) / (V1 × I1) (1)

  The power conversion efficiency E can be easily obtained by calculating the calculation unit 7 according to the input voltage V1, the input current I1, the output voltage V2, and the output current I2. In general, in the power conversion device 100, a large amount of power conversion loss occurs due to the switching control of the power element 4. For this reason, the power conversion efficiency E is a value smaller than 1.

  When the determination result received from the failure determination unit 6 is “normal” for all sensors, the calculation unit 7 sets the power conversion efficiency E to the input voltage value V1, the input current value I1, the output voltage value V2, and the output current. Calculation is performed according to the value I2, and the measured values V1, I1, V2, I2 and the power conversion efficiency E are stored in the storage unit as history data associated with each other.

  On the other hand, when the determination result received from the failure determination unit 6 indicates “failure” of one sensor, the calculation unit 7 stops the calculation and storage of the power conversion efficiency E, and detects the failed sensor. Excluding the value, the power conversion efficiency E ′ is read based on the history data already stored based on the detection value of the normal sensor.

  For example, in the determination result received from the failure determination unit 6, when the output current sensor 10 is determined as “failure” as one sensor, the input voltage value V1 that is a detection value of three normal sensors. The input current value I1 and the output voltage value V2 are compared with the input voltage value V1 ′, the input current value I1 ′, and the output voltage value V2 ′, which are various combinations of the stored history data, and the difference is minimized. And a stored power conversion efficiency E ′ corresponding to the searched combination is read at the same time.

  Here, for example, the calculation unit 7 has an input voltage value V1 ′ that minimizes the sum of squares of three differences of (V1−V1 ′), (I1−I1 ′), and (V2−V2 ′). It is conceivable to search a set having the input current value I1 ′ and the output voltage value V2 ′ from the history data as a combination that minimizes the difference.

  Note that it is also possible to simply calculate the sum instead of the sum of squares, or to calculate the sum of squares or sum after giving weights to the differences, respectively. This is defined in advance as a comparison rule using values.

  Or the calculating part 7 may memorize | store the numerical formula which can calculate power conversion efficiency E 'from the detection value of a normal sensor beforehand, and may improve a precision by calculating | requiring by calculation.

For example, as an arithmetic expression of the power conversion efficiency E ′, the following expression (2) that calculates the power conversion efficiency E ′ using the output voltage value V2 that is a normal detection value may be adopted.
Power conversion efficiency E ′ = − 0.002 × V2 ² + 0.04 × V2 + 0.8 (2)

  Thereafter, the control unit 8 estimates the detection value of the failed sensor from the power conversion efficiency E ′ obtained by the calculation unit 7 and the detection values of the three normal sensors.

For example, when the output current sensor 10 fails, the control unit 8 determines that the difference between the input voltage value V1, the input current value I1, and the output voltage value V2, which are detection values of three normal sensors, is the minimum. The stored input voltage value V1 ′, input current value I1 ′, and output voltage value V2 ′ are retrieved, and the stored power conversion efficiency E ′ is read in accordance with the retrieval result. And the control part 8 estimates output current value I2 'by following Formula (3) for output current I2'.
I2 ′ = (power conversion efficiency E ′ × V1 ′ × I1 ′) / (V2 ′) (3)

Alternatively, by using the power conversion efficiency E ′ and the input voltage value V1, the input current value I1, and the output voltage value V2 that are detection values of three normal sensors, the output current value I2 ′ is calculated by the following equation (4). It may be estimated.
I2 ′ = (power conversion efficiency E ′ × V1 × I1) / (V2) (4)

  Finally, the control unit 8 performs switching control of the power elements in the power conversion circuit 3, so that the input voltage value V1, the input current value I1, the output voltage value V2, and the estimated output current value I2 ′ are The power conversion circuit 3 is controlled to convert the voltage V of the power supply 11 into a desired output voltage and / or a desired output current, and supply it to the output load 12.

  As described above, according to the first embodiment, the power conversion efficiency E stored in correspondence with the detection values of the normal three sensors and the history data search result closest to the detection values of the normal three sensors. It is possible to estimate the detection value of one sensor determined to be faulty using '.

  As a result, it is not necessary to perform complicated control or to provide a plurality of power conversion circuits, and among the total of four sensors of the voltage sensor and current sensor of the input / output of the power conversion device used for normal control, The operation of the power conversion circuit can be continued using three normal sensors.

  In the first embodiment, the case where one failed sensor is used as the output current sensor 10 is exemplified. However, when only one other sensor fails, detection of one failed sensor by the same method is performed. The value can be estimated and the same effect can be obtained.

Embodiment 2. FIG.
Hereinafter, the power converter in Embodiment 2 of this invention is demonstrated based on drawing. In addition, the structure of the power converter device concerning Embodiment 2 of this invention is the structure similar to previous Embodiment 1 shown in FIG. 1, and is demonstrated based on FIG.

  In the first embodiment, when the determination result from the failure determination unit 6 is “normal”, the calculation unit 7 sets the power conversion efficiency E to the input voltage value V1, the input current value I1, the output voltage value V2, and It was stored as history data associated with the output current value I2. However, there is no period in which the determination result from the failure determination unit 6 is “normal”. For example, in the case of an initial failure, there is no history data, and the stored power conversion efficiency E ′ cannot be read.

  Further, when the period in which the determination result from the failure determination unit 6 is “normal” is a small number of times such as two or three times, the stored power conversion efficiency E based on the detection value of the normal sensor. 'Can be read. However, since the number of data stored as the history data is small, the power conversion efficiency E ′ specified and read from the data may be reduced in accuracy, and as a result, the failure sensor There is also a possibility that the estimation accuracy of the detected value is also lowered.

  Therefore, the calculation unit 7 in the second embodiment sets a sufficient power conversion efficiency E ′ in advance on the production line or the like so that the input voltage value V1 ′, the input current value I1 ′, the output voltage value V2 ′, and the output current value I2 ′. And stored as pre-collected data. The rest is the same as in the first embodiment.

  As described above, when the power conversion efficiency E ′ for various combinations of detection values of the four sensors is stored in advance as a database as pre-collected data, the power conversion efficiency E ′ cannot be read, or the history Even when the number of data stored as data is small, it is possible to estimate the detection value of one failed sensor while suppressing the decrease in accuracy.

  As described above, according to the second embodiment, the power conversion efficiency E ′ for various combinations of detection values of the four sensors is further stored in advance as a database as pre-collected data. As a result, the same effect as that of the first embodiment can be obtained after the detection value of one failed sensor is estimated with high accuracy without depending on the history data stored during actual operation. .

  It should be noted that the area where the power conversion efficiency E ′ is stored in association with the input voltage value V1 ′, the input current value I1 ′, the output voltage value V2 ′, and the output current value I2 ′ cannot be secured, or the production line If the pre-collected data cannot be collected by the above, an arithmetic expression that can be calculated from the detection value of the normal sensor may be stored, and the power conversion efficiency E ′ may be calculated by calculation.

For example, similarly to the equation (2) shown in the first embodiment, the following equation (5) can be adopted, and the power conversion efficiency E ′ can be obtained by calculation from the detection value of the normal sensor. .
Power conversion efficiency E ′ = − 0.002 × V2 ² + 0.04 × V2 + 0.8 (5)

  Also in this case, the effect of the second embodiment described above can be obtained.

Embodiment 3 FIG.
FIG. 2 is a diagram showing an example of the configuration of the power conversion device according to Embodiment 3 of the present invention. In FIG. 2, the power conversion apparatus 100 includes a power conversion circuit 3, a calculation unit 7, a control unit 8, an input voltage sensor 1, an input current sensor 2, and an output voltage sensor 9. A power source 11 (shown as an AC power source in FIG. 2) is connected to the input side, and an output load 12 is connected to the input side.

  Here, the configuration of FIG. 2 in the third embodiment is different from the configuration of FIG. 1 in the first embodiment in that the output current sensor 10 and the failure determination unit 6 are not provided.

  An input voltage sensor 1 that detects an input voltage value V1 is inserted between input terminals of the power conversion device 100, and an input current that detects an input current value I1 is interposed between one of the input terminals and the power conversion circuit 3. Sensor 2 is inserted.

  In addition, an output voltage sensor that detects an output voltage value V <b> 2 is inserted between the output terminals of the power conversion device 100. In the third embodiment, unlike the first embodiment, the output current sensor 10 for detecting the output current value I2 is inserted between one of the output terminals and the power conversion circuit 3. Absent. That is, the power conversion device according to the third embodiment employs a configuration in which the number of sensors to be installed is limited to three and one sensor is reduced.

  In addition, the calculation unit 7 stores in advance a database of pre-collected data in which the power conversion efficiency E ′ is associated with various combinations of detected values when there are all four sensors in a production line or the like. Keep it.

  Then, the calculation unit 7 has the input voltage value V1 ′, the input current, and the combination having the smallest difference between the input voltage value V1, the input current value I1, and the output voltage value V2 detected by the three sensors during actual operation. A set of the value I1 ′ and the output voltage value V2 ′ is specified from the pre-collected data, and the power conversion efficiency E ′ corresponding to the specified combination is read.

  In addition, when the output current value I2 ′ measured by the output current sensor 10 that is reduced in an actual apparatus is measured on a production line or the like when the above-described database is created, the output current sensor is provided outside the power conversion apparatus 100. Thus, the output current value I2 ′ can be measured by externally attaching a measuring instrument to be reduced.

Next, the control unit 8 calculates the output current I2 ′ during actual operation based on the power conversion efficiency E ′ read out by the calculation unit 7 and the detected values during actual operation of the three sensors ( Estimate according to 6).
I2 ′ = (power conversion efficiency E ′ × V1 × I1) / (V2) (6)

  Then, the control unit 8 performs switching control of the power elements in the power conversion circuit 3 in accordance with the input voltage value V1, the input current value I1, the output voltage value V2, and the estimated output current value I2 ′, which are actually measured values. By doing so, the power conversion circuit 3 is controlled, and the voltage of the power supply 11 is converted to a desired output voltage, a desired output current, or both, and supplied to the output load 12.

  As described above, according to the third embodiment, the combination of the detection values of the four sensors and the power conversion efficiency are associated with each other and stored in advance as a database as pre-collected data. The circuit configuration is reduced by one sensor. The power conversion efficiency E ′ can be read out by searching for data closest to the detected values of the three sensors collected during actual operation from the pre-collected data, and the reduced detected value of one sensor can be estimated. It has a configuration.

  As a result, it is not necessary to perform complicated control or to provide a plurality of power conversion circuits, and the operation of the power conversion circuit is executed after reducing the number of sensors used for normal control from four to three. Can be obtained, and the cost of the apparatus can be reduced.

  It should be noted that the area where the power conversion efficiency E ′ is stored in association with the input voltage value V1 ′, the input current value I1 ′, the output voltage value V2 ′, and the output current value I2 ′ cannot be secured, or the production line If the pre-collected data cannot be collected, etc., an arithmetic expression that can be calculated from the detection value of each sensor may be stored and the power conversion efficiency E ′ may be calculated by calculation.

For example, the following equation (7) is adopted in the same manner as the equation (2) shown in the previous embodiment 1 or the equation (5) shown in the previous embodiment 2, and the detection of the installed sensor is performed. It is also possible to obtain the power conversion efficiency E ′ from the value by calculation.
Power conversion efficiency E ′ = − 0.002 × V2 ² + 0.04 × V2 + 0.8 (7)

  Also in this case, the effect of the third embodiment described above can be obtained.

  In addition, the power converter device 100 in FIG. 1 and FIG. 2 describes the minimum configuration necessary for explaining the present invention, and does not limit the configuration of the present invention. The power source 11 may be direct current or alternating current, the output voltage may be direct current or alternating current, and the output load 12 may be an inverter, a motor, an electric / electronic circuit, a secondary battery, or the like.

  Further, the input voltage sensor 1, the input current sensor 2, the output voltage sensor 9, or the output current sensor 10 may be outside the power conversion apparatus 100. Also in this case, for example, each sensor and its A / D converter and the like serve as a measurement unit.

  The power conversion efficiency can be calculated using values of an input voltage sensor, an input current sensor, an output voltage sensor, and an output current sensor that are usually used to control the power conversion circuit of the power conversion device. Therefore, there is no need to add a temperature sensor to the power element or magnetic component. Further, if there is an increase in contact resistance, an increase in the wiring resistance of the connection wiring, or the like at the connection between the substrates or between the components such as the transformer and the terminal block, the loss increases. Therefore, it is possible to detect such a loss increase factor based on the power conversion efficiency.

  In addition, this invention is not limited to Embodiment 1-3 mentioned above, It cannot be overemphasized that all these possible combinations are included. For example, the power conversion efficiency E may be a fixed value.

  DESCRIPTION OF SYMBOLS 1 Input voltage sensor (input voltage measuring device), 2 Input current sensor (input current measuring device), 3 Power conversion circuit, 4 Power element, 5 Magnetic component, 6 Failure judgment part, 7 Calculation part, 8 Control part, 9 Output Voltage sensor (output voltage measuring device), 10 output current sensor (output current measuring device), 11 power supply, 12 output load, 100 power converter.

Claims (16)

A power conversion circuit that converts an input voltage into a desired output voltage;
An input voltage measuring instrument for measuring the input voltage;
An input current measuring device for measuring an input current to the power conversion circuit;
An output voltage measuring device for measuring the output voltage;
An output current measuring device for measuring an output current from the power conversion circuit;
From the measured values of four measuring instruments composed of the input voltage measuring instrument, the input current measuring instrument, the output voltage measuring instrument, and the output current measuring instrument, the power conversion efficiency in the power conversion circuit is calculated, A calculation unit that stores history data in which the measurement values of the four measuring devices and the power conversion efficiency are associated with each other in a storage unit;
A determination unit that determines the presence or absence of a failure of the four measuring devices based on the measurement values of the four measuring devices;
A control unit that performs power conversion control of the power conversion circuit,
When the determination unit receives a determination result indicating that one of the four measurement devices has failed by the determination unit, the three measurement devices that are normal among the four measurement devices Calculate the estimated power conversion efficiency based on the measured value of
When the determination unit receives a determination result indicating that one of the four measuring devices has failed by the determining unit, the three measuring devices that are normal among the four measuring devices And the estimated value of the power conversion efficiency by the calculation unit, the measured value of the one measuring device that has failed is estimated, and the power conversion control is continued. The arithmetic unit stores in advance in the storage unit an arithmetic expression for calculating power conversion efficiency without using the measurement value of the one measuring device out of the measurement values obtained by the four measuring devices. The power conversion device according to claim 1, wherein an estimated value of the power conversion efficiency is calculated using the arithmetic expression. When the determination unit receives a determination result indicating that one of the four measurement devices has failed by the determination unit, the three measurement devices that are normal among the four measurement devices And when the four measuring instruments are all normal, the comparison data using the difference values of the corresponding three measured values are compared with the history data stored in the storage unit. Based on the history data, the data closest to the measurement values of the three measuring devices is searched, and the power conversion efficiency stored as the history data corresponding to the searched data is the power conversion efficiency. The power conversion device according to claim 1, wherein the power conversion device is calculated as an estimated value. The computing unit is
Prior to actual operation of the power converter, the measurement data acquired for various combinations of the measurement values of the four measuring instruments and the power conversion efficiencies calculated corresponding to the combinations of the measurement data are associated with each other. And previously stored in the storage unit as pre-collected data,
When the determination unit receives a determination result indicating that one of the four measuring devices has failed, the measurement values of three measuring devices that are normal among the four measuring devices; Based on the comparison rule using the respective difference values of the corresponding three measured values with the previously collected data stored in the storage unit, the three previously collected data are selected from the three previously collected data. The data closest to the measurement value of the measuring device is searched, and the power conversion efficiency stored as the pre-collected data corresponding to the searched data is calculated as the estimated value of the power conversion efficiency. Power conversion device. A power conversion circuit that converts an input voltage into a desired output voltage;
An input voltage measuring instrument for measuring the input voltage;
An input current measuring device for measuring an input current to the power conversion circuit;
An output voltage measuring device for measuring the output voltage;
An arithmetic unit that calculates an estimated value of power conversion efficiency based on the measured values of three measuring devices including the input voltage measuring device, the input current measuring device, and the output voltage measuring device;
Using the measured values of the three measuring devices and the estimated value of the power conversion efficiency by the computing unit, the estimated value of the output current is calculated, and the measured values of the three measuring devices and the estimated value of the output current are used. And a control unit that performs power conversion control of the power conversion circuit. The calculation unit stores in advance a calculation formula for calculating power conversion efficiency using at least one of the measurement values obtained by the three measuring devices in a storage unit, and the power conversion efficiency is calculated using the calculation formula. The power conversion device according to claim 5, wherein an estimated value is calculated. The computing unit is
Before the actual operation of the power converter, the measurement data acquired for various combinations of the measured values of the three measuring instruments and the measured value of the output current, and the respective combinations of the measured data In association with the power conversion efficiency calculated in advance, it is stored in advance in the storage unit as pre-collected data,
Based on the comparison result by the comparison rule using the difference value of each of the corresponding three measured values between the measured values of the three measuring devices and the pre-collected data stored in the storage unit The data closest to the measured values of the three measuring devices is searched from the pre-collected data, and the power conversion efficiency stored as the pre-collected data corresponding to the searched data is the power The power conversion device according to claim 5, which is employed as an estimated value of conversion efficiency. A power conversion circuit that converts an input voltage into a desired output voltage;
An input voltage measuring instrument for measuring the input voltage;
An input current measuring device for measuring an input current to the power conversion circuit;
An output current measuring device for measuring an output current from the power conversion circuit;
An arithmetic unit that calculates an estimated value of power conversion efficiency based on the measured values of three measuring devices including the input voltage measuring device, the input current measuring device, and the output current measuring device;
The estimated value of the output voltage is calculated using the measured value of the three measuring devices and the estimated value of the power conversion efficiency by the calculation unit, and the measured value of the three measuring devices and the estimated value of the output voltage are used. And a control unit that performs power conversion control of the power conversion circuit. The calculation unit stores in advance a calculation formula for calculating power conversion efficiency using at least one of the measurement values obtained by the three measuring devices in a storage unit, and the power conversion efficiency is calculated using the calculation formula. The power converter according to claim 8. The computing unit is
Before the actual operation of the power converter, the measurement data acquired for various combinations of the measurement values of the three measuring instruments and the measurement value of the output voltage, and the respective combinations of the measurement data In association with the power conversion efficiency calculated in advance, it is stored in advance in the storage unit as pre-collected data,
Based on the comparison result by the comparison rule using the difference value of each of the corresponding three measured values between the measured values of the three measuring devices and the pre-collected data stored in the storage unit The data closest to the measured values of the three measuring devices is searched from the pre-collected data, and the power conversion efficiency stored as the pre-collected data corresponding to the searched data is the power The power conversion device according to claim 8, which is adopted as an estimated value of conversion efficiency. A power conversion circuit that converts an input voltage into a desired output voltage;
An input voltage measuring instrument for measuring the input voltage;
An output voltage measuring device for measuring the output voltage;
An output current measuring device for measuring an output current from the power conversion circuit;
An arithmetic unit that calculates an estimated value of power conversion efficiency based on the measured values of three measuring devices including the input voltage measuring device, the output voltage measuring device, and the output current measuring device;
An estimated value of the input current is calculated using the measured values of the three measuring devices and the estimated value of the power conversion efficiency by the arithmetic unit, and the measured values of the three measuring devices and the estimated value of the input current are used. And a control unit that performs power conversion control of the power conversion circuit. The calculation unit stores in advance a calculation formula for calculating power conversion efficiency using at least one of the measurement values obtained by the three measuring devices in a storage unit, and the power conversion efficiency is calculated using the calculation formula. The power conversion device according to claim 11, wherein an estimated value is calculated. The computing unit is
Before the actual operation of the power converter, the measurement data acquired for various combinations of the measured values of the three measuring instruments and the measured values of the input current, and the respective combinations of the measured data In association with the power conversion efficiency calculated in advance, it is stored in advance in the storage unit as pre-collected data,
Based on the comparison result by the comparison rule using the difference value of each of the corresponding three measured values between the measured values of the three measuring devices and the pre-collected data stored in the storage unit The data closest to the measured values of the three measuring devices is searched from the pre-collected data, and the power conversion efficiency stored as the pre-collected data corresponding to the searched data is the power The power conversion device according to claim 11, which is adopted as an estimated value of conversion efficiency. A power conversion circuit that converts an input voltage into a desired output voltage;
An input current measuring device for measuring an input current to the power conversion circuit;
An output voltage measuring device for measuring the output voltage;
An output current measuring device for measuring an output current from the power conversion circuit;
An arithmetic unit that calculates an estimated value of power conversion efficiency based on the measured values of three measuring devices including the input current measuring device, the output voltage measuring device, and the output current measuring device;
The estimated value of the input voltage is calculated using the measured value of the three measuring devices and the estimated value of the power conversion efficiency by the calculation unit, and the measured value of the three measuring devices and the estimated value of the input voltage are used. And a control unit that performs power conversion control of the power conversion circuit. The calculation unit stores in advance a calculation formula for calculating power conversion efficiency using at least one of the measurement values obtained by the three measuring devices in a storage unit, and the power conversion efficiency is calculated using the calculation formula. The power conversion device according to claim 14, wherein an estimated value is calculated. The computing unit is
Before the actual operation of the power converter, the measurement data acquired for various combinations of the measurement values of the three measuring instruments and the measurement value of the input voltage, and the respective combinations of the measurement data In association with the power conversion efficiency calculated in advance, it is stored in advance in the storage unit as pre-collected data,
Based on the comparison result by the comparison rule using the difference value of each of the corresponding three measured values between the measured values of the three measuring devices and the pre-collected data stored in the storage unit The data closest to the measured values of the three measuring devices is searched from the pre-collected data, and the power conversion efficiency stored as the pre-collected data corresponding to the searched data is the power The power conversion device according to claim 14, which is employed as an estimated value of conversion efficiency.

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