JP2001025106A - Output correction and control device for fuel cell system for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an output correction and control device for a fuel cell system for vehicles which allows the status of power generation by a fuel cell to be determined with accuracy. SOLUTION: A fuel cell controller 51 stores in an internal ROM in advance initial output characteristics in initial stages, representing current characteristics corresponding to a request output requested from a fuel cell stack 15, calculates a request current corresponding to the request output from the initial output characteristics, and temporarily fixes the output current outputted from the fuel cell stack 15 at this request current. Based on the current and voltage outputted form the fuel cell stack 15, actual output is calculated, and the status of power generation by the fuel cell stack 15 is determined from the comparison of the actual output with the requested output.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an output correction control device for a vehicular fuel cell system that accurately determines a power generation state of a fuel cell and controls an actual output from the fuel cell to a required output.

[0002]

2. Description of the Related Art Conventionally, as an output correction control device of a vehicle fuel cell system, an output which can be taken out according to the power generation state of the fuel cell when controlling the actual output from the fuel cell to the required output. Is known.

In this output correction control device, when a required output requested by a vehicle-side controller is taken out of a fuel cell, if a difference occurs between the required output and an actual output, the fuel cell monitored during traveling is monitored. The output that can be taken out is corrected according to the power generation state of the fuel cell using instantaneous data such as the current, voltage, reformed gas pressure, and temperature of the stack.

[0004]

However, in a conventional fuel cell vehicle, a detected current signal and a detected voltage signal of the fuel cell, which constantly fluctuate during running, are sampled to determine the power generation state of the fuel cell. I was asking.

For this reason, the vehicle accelerates and decelerates particularly frequently,
When sampling is performed in a situation where the current or voltage output from the fuel cell fluctuates greatly, the deviation from the steady-state current-voltage characteristic of the fuel cell has increased. as a result,
There has been a problem that it is difficult to accurately determine the power generation state of the fuel cell.

[0006] In this case, the correction amount used for controlling the fuel cell is also shifted, so that there is a problem that the response time until the required output required for the fuel cell is increased.

[0007] The present invention has been made in view of the above,
An object of the present invention is to provide an output correction control device for a vehicle fuel cell system that can accurately determine the power generation state of a fuel cell.

[0008]

According to the first aspect of the present invention,
In order to solve the above-mentioned problem, a storage means for preliminarily storing an initial output characteristic at an initial stage representing a current characteristic corresponding to a required output required for the fuel cell, and calculating a required current corresponding to the required output from the initial output characteristic. Request current calculation means, output current fixing means for temporarily fixing the output current output from the fuel cell to this request current, and actual output for calculating the actual output based on the current and voltage output from the fuel cell The gist of the invention is to provide a calculation means and a power generation state determination means for determining the power generation state of the fuel cell by comparing the actual output with the required output.

According to a second aspect of the present invention, in order to solve the above-mentioned problems, according to the pressure and temperature applied to the fuel cell,
A correction coefficient calculating means for calculating a correction coefficient relating to an output that can be taken out of the fuel cell; a request output correcting means for correcting a required output required for the fuel cell using the correction coefficient; Output characteristic correction means for correcting the initial output characteristic using a correction coefficient if the output does not match the previous required output, and calculating a second required current corresponding to the required output from the corrected second output characteristic The present invention further comprises a second required current calculating means for temporarily fixing the output current output from the fuel cell to the second required current by the output current fixing means.

According to a third aspect of the present invention, in order to solve the above-mentioned problems, the second required current calculating means calculates the second required current from the corrected second output characteristic when the second required current cannot be calculated. A maximum required current calculating means for calculating a maximum possible required current; anda maximum pressure calculating means for calculating a settable maximum pressure serving as a required output at the maximum required current, wherein the pressure applied to the fuel cell is maximized. The gist of the present invention is that the pressure is controlled so as to be a pressure, and the output current output from the fuel cell by the output current fixing means is temporarily fixed to the maximum required current.

According to a fourth aspect of the present invention, in order to solve the above-mentioned problems, when the pressure of the fuel cell cannot be increased,
The gist of the present invention is to provide a notifying means for notifying that the output of the fuel cell is restricted.

According to a fifth aspect of the present invention, in order to solve the above-mentioned problem, the power generation state determining means determines that the fuel cell has deteriorated when the actual output of the fuel cell does not match the required output. And a deterioration coefficient calculating means for calculating a deterioration coefficient of the fuel cell based on the current and voltage output from the fuel cell and the required output, and correcting the correction coefficient calculated by the correction coefficient calculating means. Make a summary.

[0013]

According to the first aspect of the present invention, initial initial output characteristics representing current characteristics corresponding to the required output required for the fuel cell are stored in advance, and the required output is calculated from the initial output characteristics. Is calculated, and the output current output from the fuel cell is temporarily fixed to the required current. Here, the actual output is calculated based on the current and the voltage output from the fuel cell, and the power generation state of the fuel cell is determined by comparing the actual output with the required output, thereby accurately determining the power generation state of the fuel cell. You can judge well.

According to the second aspect of the present invention, a correction coefficient relating to the output that can be taken out of the fuel cell is calculated in accordance with the pressure and temperature applied to the fuel cell, and the required output required for the fuel cell is calculated. The correction is performed using the correction coefficient. If the required output after the correction does not match the required output before the correction, the initial output characteristic is corrected using the correction coefficient, and the second output characteristic corresponding to the required output is corrected from the second output characteristic after the correction. By calculating the required current, the output current output from the fuel cell is temporarily fixed to the second required current. Therefore, even when the required output is corrected, the power generation state of the fuel cell can be accurately determined. You can judge well. In addition, responsiveness during driving the vehicle can be improved.

According to the present invention, when the second required current cannot be calculated, the maximum required current that can be calculated from the corrected second output characteristic is calculated, and the maximum required current is calculated. By calculating the maximum pressure that can be set as the required output with the required current, the pressure applied to the fuel cell is controlled to be the maximum pressure, and the output current output from the fuel cell is set to this maximum required current. Since the second required current cannot be calculated because the correction coefficient is too small, the power generation state of the fuel cell can be accurately determined, for example, because it is temporarily fixed.

According to the present invention, when the pressure of the fuel cell cannot be increased, the fact that the output of the fuel cell is limited is notified to change the power generation state of the fuel cell. The driver can be notified.

According to the present invention, when the actual output of the fuel cell does not match the required output,
It is determined that the fuel cell has deteriorated, and the correction coefficient for the output that can be taken out of the fuel cell is corrected by calculating the deterioration coefficient of the fuel cell based on the current and voltage output from the fuel cell and the required output. Thus, even when the fuel cell is deteriorated, it is possible to prevent a decrease in the driving performance of the fuel cell vehicle.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing a configuration of a fuel cell system mounted on a fuel cell vehicle according to one embodiment of the present invention.

In the fuel reformer 11, a reformed gas containing hydrogen is generated from hydrocarbons, alcohols and the like. on the other hand,
The compressor 13 compresses air and supplies the compressed air to the fuel cell stack 15 and the fuel reformer 11.

In the fuel cell stack 15, the fuel reformer 1
Power is generated using hydrogen contained in the reformed gas from No. 1 and oxygen contained in the air from the compressor 13. The power distributor 17 distributes the power generated by the fuel cell stack 15 to the vehicle load 19 and the secondary battery 21.

The vehicle load 19 is a load generated when a motor for driving the vehicle or other auxiliary equipment is driven. The secondary battery 21 is connected in parallel with the vehicle load, charges the power recovered from the motor by regeneration during braking, and assists the power supplied to the motor during rapid acceleration.

From the fuel cell stack 15 to the fuel reformer 11
A pressure adjustment valve 31 is provided in the middle of the pipe of the exhaust air discharged to the fuel cell stack 15 to adjust the pressure of the exhaust air flowing into the fuel cell stack 15. The fuel cell stack 15
A pressure regulating valve 33 for regulating the pressure of the reformed gas flowing into the fuel cell stack 15 is provided in the middle of the pipe of the reformed gas discharged from the fuel reformer 11 to the fuel reformer 11.

The stack voltage sensor 35 and the stack current sensor 37 detect the voltage and the current generated by the fuel cell stack 15, respectively, and
Output to

The pressure sensor 41 is provided in the middle of the pipe of the reformed gas flowing into the fuel cell stack 15 from the fuel reformer 11, detects the pressure of the reformed gas, and detects the pressure of the reformed gas.
Output to 1. The pressure sensor 43 is provided in the piping of the air flowing from the compressor 13 to the fuel cell stack 15, detects the pressure of the air, and outputs the detected pressure to the fuel cell control device 51.

The temperature sensors 45 and 47 are respectively provided in the pipes of the exhaust reformed gas and the exhaust air discharged from the fuel cell stack 15 to the fuel reformer 11, and detect the temperatures of the exhaust reformed gas and the exhaust air. And outputs it to the fuel cell control device 51.

The fuel cell controller 51 has a RAM for storing control data, a control program and an initial output characteristic OP.
ROM for storing ini and hydrogen utilization rate table, and CPU for controlling fuel cell system according to control program
And inside.

The drive control unit 53 calculates the vehicle load power by summing the powers required by the respective auxiliary machines constituting the vehicle load 19, and calculates the vehicle load power based on the power capacity remaining in the secondary battery 21 and the vehicle load power. A required output Pout required for the fuel cell stack 15 is calculated and transmitted to the fuel cell control device 51, and a distribution ratio for distributing the power generated by the fuel cell stack 15 to the vehicle load 19 and the secondary battery 21 is calculated. And sends it to the power distributor 17.

Next, FIG. 2 is a diagram showing the relationship between the current that can be taken out of the fuel cell stack 15 and the electric power.

As shown in FIG. 2, it is shown that the stack current and the stack power correspond one-to-one in a range of about 300 V and a current of about 300 A, which is a power source of the electric vehicle. This relationship indicates that the higher the pressure of the reformed gas and the air and the higher the stack temperature, the larger the power for the same current value.

Next, FIG. 3 is a diagram showing a relationship between a pressure or a temperature applied to the fuel cell stack 15 and a correction coefficient with respect to a required output required when calculating a retrievable output.

The correction coefficient has a current dependency, and as shown in FIG. 3, the correction coefficient shifts to a lower direction as the current increases.

FIG. 4 is a diagram showing the initial output characteristics and the corrected output characteristics of the fuel cell stack 15 used when performing the output correction control process.

When the requested output from the drive control unit 53 is output at a current value calculated from the initial output characteristic OPini without considering the power generation state of the fuel cell stack 15, the fuel cell stack 15 deteriorates. Sometimes, the required output is not satisfied. Therefore, the correction output characteristic is calculated by correcting the initial output characteristic OPini using the correction coefficient, the correction current for the required output is calculated from the correction output characteristic, and the output current from the fuel cell stack 15 is output with this correction current. Control may be performed as follows.

Next, FIG. 5 is a diagram showing that the ratio of the target voltage of the fuel cell stack 15 to the actual detected voltage can be converted to the hydrogen utilization rate.

The hydrogen utilization rate indicates the ratio of consumed hydrogen to the total amount of hydrogen flowing to the fuel cell stack 15. As shown in FIG. 5, the fuel cell vehicle is assumed to be used at a hydrogen utilization of about 70 to 80%.

Next, a normal output correction control process by the fuel cell control device 51 and an output correction control process according to the power generation state of the stack will be described with reference to FIGS. .

First, normal output correction control processing by the fuel cell control device 51 will be described.

In step S5, the pressure of the reformed gas is detected from the pressure sensor 41, the stack temperature is detected from the temperature sensor 45, and the current correction coefficient Kr is changed to the correction coefficient Kp based on the gas pressure as shown in FIG. , A correction coefficient Kt based on the stack temperature, and a deterioration coefficient Kd indicating the degree of deterioration of the stack.

## EQU1 ## Calculated as Kr = Kp × Kt × Kd at regular intervals.

When the calculation process in step S5 is the first time, the calculation process is performed with the deterioration coefficient Kd = 1.

In step S10, when the required output Pout is received from the drive control device 53, the required output Pout from the drive control device 53 is held in the internal RAM. If the requested output Pout cannot be received from the drive control device 53, the requested output Pout at the time of the previous reception stored in the internal RAM is read.

In step S20, referring to FIG. 4, the initial output characteristic OPini is converted into a required output conversion current Iout_1 corresponding to the required output Pout. At the same time, the required output Pout is corrected by multiplying it by the current correction coefficient Kr,
The correction request output Pout_1 is obtained.

Then, in a step S30, it is determined whether or not the required correction output Pout_1 matches the required output Pout. If they match, the process proceeds to step S40,
The output current from the fuel cell stack 15 is calculated in step
Is output with the required output conversion current Iout_1 obtained in step, and the process proceeds to step S110.

On the other hand, if they do not match, the process proceeds to step S50, and referring to FIG. 4, the required output is obtained from the corrected output characteristic OPini_r obtained by multiplying the current output coefficient OPr by the current correction coefficient Kr. Read the correction current Iout_2 corresponding to Pout.

In step S60, referring to FIG. 4, it is determined whether the correction current Iout_2 has been read from the initial output characteristic OPini. If the correction current Iout_2 has been read, the process proceeds to step S70, and the fuel cell stack 1
5 is the correction current I obtained in step S50.
out_2 and output to step S110.

On the other hand, if the correction current Iout_2 cannot be read, the current correction coefficient Kr is too small and the correction current Iout_2 does not exist on the correction output characteristic OPini_2. Then, the pressure of the reformed gas is read from the pressure sensor 41 provided in the controller, and it is determined whether or not the current pressure can be increased without exceeding a predetermined value.

If the pressure of the reformed gas can be increased, the process proceeds to step S90, where the maximum output current Iout_2max that can be output on the corrected output characteristic OPini_2 is read, and the required output Pout can be set with the maximum output current Iout_2max. Calculate the maximum pressure back. The pressure control valve 33 provided at the outlet of the fuel cell stack 15 is controlled until the pressure of the reformed gas reaches the settable maximum pressure calculated by the pressure sensor 45 provided at the inlet of the fuel cell stack 15. To increase pressure. As a result, the output current from the fuel cell stack 15 is output as the maximum output current Iout_2max obtained,
Proceed to step S110.

In this case, the shortage of the output current is controlled to increase the pressure of the reformed gas while compensating by discharging from the secondary battery 21. Also,

When Iout_2 = Iout_2max, the output compensation from the secondary battery 21 is stopped.

On the other hand, if the pressure of the reformed gas cannot be increased, the process proceeds to step S100, and an output restriction warning signal is transmitted to the drive control device 53. Then, the output current from the fuel cell stack 15 is output at the maximum output current Iout_2max obtained as described above, and the process proceeds to step S110.

In this case, since the drive control device 53 receives the output restriction warning signal from the fuel cell control device 51, the drive control device 53 displays a warning on the display unit provided on the meter panel, so that the driver enters the output restriction region. Notify that.

In addition,

## EQU3 ## If the pressure reaches the upper limit while Iout_2> Iout_2max, the output compensation by the secondary battery 21 is continued. But,
Similarly, when the output compensation cannot be continued without the power capacity of the secondary battery 21, a warning is displayed to notify that the vehicle has entered the output restriction area.

Since the correction coefficient Kr is updated at regular intervals, the correction current Iout_2 is updated at the same time. As a result, when the updated correction current Iout_2 returns from the output limited region to the output available region, a warning cancel signal is transmitted to the drive control device 53 to cancel the above-described warning display. In this case, since the drive control device 53 receives the warning cancellation signal from the fuel cell control device 51, the drive control device 53 cancels the warning display from the display unit on the meter panel, and notifies the driver that the vehicle has entered the output enabled area.

As described above, steps S40 and S7
By 0, S90, and S100, the output current output from the fuel cell stack 15 is temporarily fixed.

Next, the output correction control based on the state of the fuel cell stack 15 by the fuel cell control device 51 will be described.

First, in step S110, the stack voltage Vsen and the stack current Ise detected by the stack voltage sensor 35 and the stack current sensor 37, respectively.
Enter n. Until the next detection processing in step S110 is performed, the current detection value is held in the RAM in the fuel cell control device 51, and the excess or deficiency during that time is compensated by charging and discharging by the secondary battery 21. It shall be.

Then, in step S120,

Assuming that Iout_2 ≦ Iout2_max, the detected stack current Isen
The actual output based on the stack voltage Vsen and the value obtained by subtracting the output target allowable width ΔP from the required output Pout at the start of sampling are:

## EQU5 ## It is compared whether Isen × Vsen <(Pout− △ P).

However, assuming that the lower limit voltage for lowering the stack voltage Vsen is the lower limit voltage Vlow for the stack,

## EQU6 ## Vsen ≧ Vlow.

Here,

## EQU7 ## If Isen × Vsen ≧ (Pout- 戻 り P) holds, there is no problem such as deterioration in the power generation state of the fuel cell stack 15, and the process returns to step S5 to continue the output. Repeat the process.

On the other hand, when the inequality (7) is not satisfied, it is determined that the flow rate of hydrogen to the fuel cell stack 15 is insufficient and the specified hydrogen utilization rate is not obtained.

Then, in step S130, as the voltage target value,

## EQU8 ## Vout = Pout / Isen is calculated.

Further, the detection voltage Vsen and the target voltage Vout
As the voltage ratio between

## EQU9 ## Voltage ratio = Vsen / Vout is calculated.

Here, referring to FIG. 5, voltage ratio Vsen stored in ROM in fuel cell control device 51 in advance.
The current hydrogen utilization rate is calculated from the hydrogen utilization rate table for / Vout.

Then, in step S140, a request to increase the amount of hydrogen is output to the fuel reformer 11 so as to achieve the target hydrogen utilization rate. The fuel reformer 11 that has received the request for increasing the amount of hydrogen from the fuel cell control device 51 increases the amount of reformed gas generated in response to the request for increasing the amount of hydrogen.

After the correction of the hydrogen flow rate, step S15
At 0, the stack current Isen and the stack voltage Vsen are again
And the required output Pout is compared with

Pout = Isen × Vsen It is determined whether or not both coincide.

Here, if they match, the process returns to step S5, and the above-described reception determination processing is repeated.

On the other hand, if they do not match, it is determined that the fuel cell stack 15 has deteriorated because the actual output is insufficient even after the correction of the hydrogen flow rate.

Then, in step S160, as the deterioration coefficient Kd,

Calculate Kd = Vsen / Vout.

At this time, a warning signal indicating that the possibility of limiting the output due to deterioration of the fuel cell stack 15 has increased, or a warning signal prompting inspection or replacement when the deterioration coefficient Kd has become 0.8 or less. Is transmitted to the drive control device 53. In this case, since the drive control device 53 receives the warning signal from the fuel cell control device 51, the drive control device 53 displays a warning on the display unit on the meter panel to notify the driver of the above-described contents.

Then, the process returns to step S5 to repeat the processing. In this case, in step S5, the current correction coefficient Kr is corrected using the new deterioration coefficient Kd less than one.

As described above, the initial output characteristics at the initial stage representing the current characteristics corresponding to the required output required for the fuel cell stack are stored in advance, and the required current corresponding to the required output is calculated from the initial output characteristics. The output current output from the fuel cell stack is temporarily fixed to the required current. Here, the actual output is calculated based on the current and the voltage output from the fuel cell stack, and the power generation state of the fuel cell stack is determined by comparing the actual output with the required output. The state can be accurately determined.

Further, according to the pressure and temperature applied to the fuel cell stack, a correction coefficient relating to the output that can be taken out of the fuel cell stack is calculated, and the required output required for the fuel cell stack is corrected using the correction coefficient. And
If the required output after the correction does not match the required output before the correction, the initial output characteristic is corrected using the correction coefficient, and the second required current corresponding to the required output is obtained from the corrected second output characteristic. Is calculated, the output current output from the fuel cell stack is temporarily fixed to the second required current. Therefore, even if the required output is corrected, the power generation state of the fuel cell stack can be accurately determined. You can judge well. In addition, responsiveness during driving the vehicle can be improved.

Further, when the second required current cannot be calculated, the maximum required current that can be calculated from the corrected second output characteristic is calculated, and the required output can be set with the maximum required current. By calculating the maximum pressure, the pressure applied to the fuel cell stack is controlled to be the maximum pressure, and the output current output from the fuel cell stack is temporarily fixed to this maximum required current. Therefore, for example, even when the correction coefficient is too small to calculate the second required current, the power generation state of the fuel cell stack can be accurately determined.

Further, when the pressure of the fuel cell stack cannot be increased, it is possible to notify the driver of the power generation state of the fuel cell stack by notifying that the output of the fuel cell stack is limited. it can.

If the actual output of the fuel cell stack does not match the required output, it is determined that the fuel cell stack has deteriorated, and based on the current and voltage output from the fuel cell stack and the required output, By calculating the deterioration coefficient of the fuel cell stack, the correction coefficient relating to the output that can be taken out of the fuel cell stack is corrected. Can be prevented.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a fuel cell system mounted on a fuel cell vehicle according to one embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between current and power that can be taken out of a fuel cell stack.

FIG. 3 is a diagram showing a relationship between a pressure or a temperature applied to a fuel cell stack and a correction coefficient with respect to a required output required when calculating a retrievable output.

FIG. 4 is a diagram showing initial output characteristics and corrected output characteristics of a fuel cell stack used when performing output correction control processing.

FIG. 5 is a diagram showing that a ratio of a target voltage of a fuel cell stack to an actual detected voltage can be converted into a hydrogen utilization rate.

FIG. 6 is a flowchart for explaining a normal output correction control process by the fuel cell control device and an output correction control process according to the power generation state of the stack.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Fuel reformer 13 Compressor 15 Fuel cell stack 19 Vehicle load 21 Secondary battery 31, 33 Pressure regulating valve 35 Stack voltage sensor 37 Stack current sensor 41, 43 Pressure sensor 45, 47 Temperature sensor 51 Fuel cell controller 53 Drive control apparatus

Continued on the front page F term (reference) 5H027 BA01 BA09 BA10 DD03 KK02 KK05 KK44 KK51 KK54 KK56 MM26 5H115 PG04 PI16 PI18 PI29 PI30 PU01 QE08 QN03 SE06 TI05 TI06 TI10 TR19 TU01 TU04 TZ07

Claims (5)

[Claims] 1. A storage means for storing in advance an initial output characteristic representing a current characteristic corresponding to a required output required for a fuel cell, and a required current for calculating a required current corresponding to the required output from the initial output characteristic. Calculation means; output current fixing means for temporarily fixing the output current output from the fuel cell to the required current; and actual output calculation means for calculating the actual output based on the current and voltage output from the fuel cell And a power generation state determining means for determining a power generation state of the fuel cell by comparing the actual output with the required output. 2. A correction coefficient calculating means for calculating a correction coefficient relating to an output which can be taken out of the fuel cell in accordance with a pressure and a temperature applied to the fuel cell, and a required coefficient required for the fuel cell is calculated using the correction coefficient. Output correction means for correcting the initial output characteristic using a correction coefficient when the required output after correction does not match the required output before correction; and A second required current calculating means for calculating a second required current corresponding to the required output from the output characteristics of the second output characteristic, wherein the output current output from the fuel cell by the output current fixing means is used as the second required current. 2. The output correction control device for a vehicle fuel cell system according to claim 1, wherein the output correction control device is temporarily fixed. 3. The second demanded current calculation means, when the second demanded current cannot be calculated, calculates the corrected second demanded current.
The fuel cell, comprising: a maximum required current calculating unit that calculates a maximum required current that can be calculated from the output characteristics of the fuel cell; anda maximum pressure calculating unit that calculates a settable maximum pressure that becomes a required output with the maximum required current. 3. The method according to claim 2, wherein the pressure applied to the fuel cell is controlled so as to become a maximum pressure, and the output current output from the fuel cell is temporarily fixed to the maximum required current by the output current fixing means. Output correction control device for vehicle fuel cell system. 4. A fuel cell for a vehicle according to claim 3, further comprising a notifying unit for notifying that the output of the fuel cell is limited when the pressure of the fuel cell cannot be increased. Output correction controller for the system. 5. The power generation state determination means, when the actual output of the fuel cell and the required output do not match, determines that the fuel cell has deteriorated, and determines the current and voltage output from the fuel cell. The vehicle fuel cell system according to claim 2, further comprising: a deterioration coefficient calculating unit that calculates a deterioration coefficient of the fuel cell based on the required output, wherein the correction coefficient calculated by the correction coefficient calculating unit is corrected. Output correction control device.