JP2781144B2 - Control method of AC / DC converter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling an AC / DC converter in which the AC / DC converter is controlled by a multiplexed control device.

[0002]

2. Description of the Related Art FIG.
FIG. 1 is a block diagram showing a configuration of a control device to which a conventional control method for an AC / DC converter shown in Japanese Patent Application Laid-Open Publication No. H10-209,086 is applied. In the figure, 1 is a transformer for conversion, 2 is a forward converter for converting AC power to DC power, and a thyristor converter operating as an inverse converter for converting DC power to AC power, and 3 is a thyristor converter. 2 is a DC reactor for output smoothing. 4A and 4B are multiplexed control devices of the AC / DC converter, and 5 is a gate pulse generator that generates a gate pulse to the thyristor converter 2 based on signals from the control devices 4A and 4B. Reference numeral 6 denotes a DC current transformer (hereinafter referred to as DCCT) for detecting a DC current Idc of the thyristor converter 2 and inputting the detected DC current to each of the control devices 4A and 4B. Reference numeral 7 denotes a DC transformer (hereinafter referred to as DCPT) which detects the DC voltage Vdc of the thyristor converter 2 and inputs the detected DC voltage Vdc to each of the control devices 4A and 4B. Reference numeral 8 denotes an AC transformer (hereinafter, referred to as ACPT) that detects the voltage of the AC system and inputs the AC voltage Vac to each of the control devices 4A and 4B.
It is.

In the control devices 4A and 4B, 9A and 9B are constant current control circuits as control circuits for controlling a DC current to a predetermined value, and 10A and 10B control a DC voltage to a constant value. This is a constant voltage control circuit as a control circuit that performs the control. Reference numerals 11A and 11B denote constant margin angle control circuits for securing a minimum margin angle in order to prevent commutation failure. 12A and 12B are DC current I from DCCT6.
A current command value added (subtracted) to dc, 13A, 1
Reference numeral 3B denotes an adder for adding the current command values 12A and 12B to the DC current Idc in opposite polarities and supplying the result to the constant current control circuits 9A and 9B. 14A and 14B are voltage command values to be added (subtracted) to the DC voltage Vdc from the DCPT 7;
A and 15B are DC voltage Vdc and their voltage command values 14A and 1
4B are added in reverse polarity, and the constant voltage control circuits 10A and 10B are added.
Is an adder to be supplied.

16A and 16B are constant current control circuits 9A and 9
B, a selection circuit for selecting an output to be used for control from the outputs of the constant voltage control circuits 10A and 10B and the constant margin angle control circuits 11A and 11B. 17A and 17B are transmission circuits between the duplicated control devices 4A and 4B.
A, 18B is a dual system selection for selecting an appropriate control output from the output of the selection circuit 16B (16A) of the partner device exchanged by the transmission circuits 17A, 17B and the output of the selection circuit 16A (16B) of the own device. Circuit. Reference numerals 19A and 19B denote phase control circuits for determining the timing of the gate pulse based on the control output selected by the duplex system selection circuits 18A and 18B. Reference numerals 20A and 20B denote the phase control circuits 19A and 20B based on the AC voltage Vac from the ACPT 8. , 19B.

Next, the operation will be described. Current command value 1
The same 2A, 12B and the same voltage command values 14A, 14B are given to the two control devices 4A, 4B, respectively. The DC current Idc from the DCCT 6, the DC voltage Vdc from the DCPT 7, and the AC voltage from the ACPT 8 are provided. Vac is also 2
The same input is given to the two control devices 4A and 4B. The DC current Idc and the current command values 12A and 12B are input to the adders 13A and 13B in opposite polarities, and when the DC current Idc deviates from the current command values 12A and 12B, the adders 13A and 13B Output is constant current control circuit 9
A and 9B are input to change the control angle of the thyristor converter 2 so that the current becomes constant.

Similarly, in the adders 15A and 15B, when the DC voltage Vdc input with the opposite polarities and the voltage command values 14A and 14B deviate, the adders 15A and 15B
The output of 5B is input to the constant voltage control circuits 10A and 10B, and the control angle of the thyristor converter 2 is changed so that the voltage becomes constant. Further, the constant margin angle control circuit 11
A and 11B also output a signal for determining the control angle of the thyristor converter 2 based on information on the DC current Idc and the AC voltage Vac. These constant current control circuits 9A, 9B, constant voltage control circuits 10A, 10B, and constant margin angle control circuits 11A, 1
1B, select circuits 16A, 16B
Control device 4 by selecting, for example, the minimum value.
A and 4B control outputs are determined.

[0007] However, as shown in the figure, multiplexing (duplexing) is performed, and a plurality of (two) control devices 4A and 4B are provided.
If there is, the outputs of the selection circuits 16A and 16B do not always match due to changes in circuit constants and constituent elements. Therefore, the selection circuits 16A, 16A,
It is necessary to exchange the output of 16B via transmission circuits 17A and 17B and to collate each other. As a result of the comparison, if the two do not match, in order to take a safe side, the control angle of the larger one of the control angles on the forward converter side and the smaller control angle on the inverse converter side are used to obtain the safety side. , 18B. The control outputs selected by the dual system selection circuits 18A and 18B are input to the phase control circuits 19A and 19B, and the phase control circuits 19A and 19B determine the timing of the gate pulse based on the control outputs. This timing signal is sent to the gate pulse generator 5, and a gate signal based on the timing is output from the gate pulse generator 5, and the thyristor converter 2 is controlled.

[0008]

Since the conventional method of controlling the AC / DC converter is configured as described above, two constant current control circuits 9A and 9B and two constant voltage control circuits 10A and 10A are used.
Since no correction is made to 10B, once a difference occurs in the output between the two control devices 4A and 4B, the control will not be reduced forever, and the control will not be improved. Since the control output is selected while checking the output, there is a problem that a delay element is included for the data transfer time between the two systems and the system becomes unstable.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide a method of controlling an AC / DC converter in which the outputs of control circuits in each system match.

Another object of the present invention is to provide a method of controlling an AC / DC converter so that even if a control device of one system outputs an abnormal value, the control device of the system does not affect the other system as much as possible. It is a further object of the present invention to provide a control method for an AC / DC converter that can make a determination based only on information in its own device as much as possible when collating outputs.

[0011]

According to a first aspect of the present invention, there is provided a method for controlling an AC / DC converter according to the present invention, wherein each of a plurality of control devices is adapted to a difference between output values of control circuits of its own device and another device. The amount is added to the input value of the control circuit of the own device.

According to a second aspect of the present invention, there is provided a control method of an AC / DC converter according to a second aspect of the present invention, wherein each control device of a plurality of systems controls the own device in accordance with a difference between output values of control circuits of the own device and another device. The circuit parameters are modified.

According to a third aspect of the present invention, there is provided a control method of an AC / DC converter according to a third aspect of the present invention. An abnormality is determined, and only when the output is normal, an amount corresponding to the difference between the output values is added to the input value of the control circuit of the own device.

According to a fourth aspect of the present invention, in the control method of the AC / DC converter according to the present invention, in each of a plurality of control devices, a difference between a previous output value of the own device and a current output value is within a specified value. In this case, the output value is immediately transmitted, and when the output value is equal to or larger than the specified value, the output value is transmitted according to the result of comparison with the output value of another device.

[0015]

According to a first aspect of the present invention, there is provided a method for controlling an AC / DC converter, comprising the steps of: inputting an amount corresponding to a difference between an output value of a control circuit of its own device and an output value of a control circuit of another device to an input of the control circuit of its own device; By adding to the values, the output values of each system are corrected so that they become the same, eliminating the need to exchange and verify the control output of each system every time, thereby enabling stable control without time delay effects. Implement a converter control method.

According to a second aspect of the present invention, there is provided a method for controlling an AC / DC converter, comprising the steps of: setting a parameter of a control circuit of the own device in accordance with a difference between an output value of the own device control circuit and an output value of a control circuit of another device; By correcting the deviation of the control circuit parameters and structure of each system and correcting them, it is not necessary to check the control output of each system every time, and stable control without the influence of time delay is possible. A control method for a simple AC / DC converter is realized.

According to a third aspect of the present invention, there is provided a method for controlling an AC / DC converter in which normality is confirmed by discrimination based on an output value of a control circuit of the own device and an output value of a control circuit of another device. Only by adding an amount corresponding to the difference between the output values to the input value of the control circuit of the own device, when one system is abnormal and sending out an outrageous output value, the output of each system is Correction of a normal system in order to match the values is prevented, and the normality of the control system is maintained.

According to a fourth aspect of the present invention, there is provided a method for controlling an AC / DC converter, comprising comparing a previous output value of the own device with a present output value, and only when the difference is equal to or more than a specified value, By sending a control output according to the result of comparison with the output value of the device, always make a judgment using the information of the own device to eliminate the effect of the time delay, and when the output value is significantly different from the previous value The reliability is also ensured by checking the output values of other devices.

[0019]

【Example】

Embodiment 1 FIG. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram illustrating a configuration of a control device to which the control method of the AC / DC converter according to the first embodiment is applied. In the figure, 1 is a conversion transformer, 2 is a thyristor converter,
3 is a DC reactor, 4A and 4B are control devices, 5 is a gate pulse generator, 6 is DCCT, 7 is DCPT, and 8 is A
CPT, 9A and 9B are constant current control circuits as control circuits, 10A and 10B are constant voltage control circuits as control circuits, 11A and 11B are constant margin angle control circuits, 12A and 12
B is a current command value, 13A and 13B are adders, 14A and 1
4B is a voltage command value, 15A and 15B are adders, 16A and
16B is a selection circuit, 19A and 19B are phase control circuits, 2
Reference numerals 0A and 20B denote synchronization detection circuits, which are the same as or equivalent to the conventional ones denoted by the same reference numerals in FIG.

Reference numerals 21A and 21B denote adders for adding the outputs of the constant current control circuits 9A and 9B of the counterpart device and the own device in opposite polarities, and reference numerals 22A and 22B denote constants based on the outputs of the adders 21A and 21B. This is a correction control circuit for a constant current control circuit that generates a correction signal for correcting the inputs of the current control circuits 9A and 9B. The correction control circuits 23A and 23B add the correction signals to the outputs of the adders 13A and 13B in reverse polarity. It is an adder. 24A and 24B are adders for adding the outputs of the constant voltage control circuits 10A and 10B of the partner device and the own device in opposite polarities,
5A and 25B are constant voltage control circuit correction control circuits for generating correction signals for correcting the inputs of the constant voltage control circuits 10A and 10B based on the outputs of the adders 24A and 24B. The correction signal is added to the adder 15
This is an adder that adds the outputs of A and 15B in reverse polarity. 2
Reference numerals 7, 28, 29, and 30 denote transmission circuits that exchange the outputs of the constant current control circuits 9A and 9B and the constant voltage control circuits 10A and 10B, which are exchanged between the control devices 4A and 4B.

The control device 4 according to the first embodiment
A, 4B are the adders 21A, 21B, 23A,
23B, 24A, 24B, 26A, 26B, correction control circuits 22A, 22B for constant current control circuits, correction control circuits 25A, 25B for constant voltage control circuits, and the duplex system selection circuits 18A, 18B are omitted. 5 is different from the conventional one denoted by the same reference numeral in FIG.

Next, the operation will be described. Example 1
In the same manner as in the conventional case, the current command value 12A, 1
2B and the voltage command values 14A and 14B
The same is given for A, 4B and DCCT
DC current Idc from DC6, DC voltage Vd from DCPT7
c, the AC voltage Vac from the ACPT 8 also has two control devices 4
The same input is given to A and 4B. The DC current Idc is added to the adders 13A, 23A or 13B, 2
The DC voltage Vdc is applied to the constant current control circuits 9A and 9B via 3B and to the constant voltage control circuits 10A and 10B via the adders 15A and 26A or 15B and 26B.
The outputs of the constant current control circuits 9A and 9B and the outputs of the constant voltage control circuits 10A and 10B are mutually exchanged between the two control devices 4A and 4B via transmission circuits 27, 28, 29 and 30, respectively. The outputs of the constant current control circuits 9A and 9B are output from adders 21A and 21B, respectively.
The outputs of B are added in opposite polarities by adders 24A and 24B.

The outputs of the adders 21A and 21B are output from the correction control circuits 22A and 22A for the constant current control circuit having a large time constant.
The correction signal is input to the adders 23A and 23B from the correction control circuits 22A and 22B for the constant current control circuit. Similarly, the outputs of the adders 24A and 24B are input to the constant voltage control circuit correction control circuits 25A and 25B having a large time constant, and the correction signals are added from the constant voltage control circuit correction control circuits 25A and 25B. Vessel 26A,
26B. The adders 23A and 23B output the outputs of the constant current control circuit correction control circuits 22A and 22B, respectively.
The adders 13A and 13B provide the DC current Idc and the current command value 12
A and 12B are added in the opposite polarity to the output signal, and the resulting signal is added to the constant current control circuits 9A and 9B. Similarly, in the adders 23A and 23B, the outputs of the constant voltage control circuit correction control circuits 25A and 25B are added to the adders 15A and 23B.
A and 15B are DC voltage Vdc and voltage command values 14A and 14B
Is added in the opposite polarity to the output signal,
This is input to the constant voltage control circuits 10A and 10B. In this way, the correction is performed so that the output difference between the two control devices 4A and 4B becomes small.

The outputs of the constant current control circuits 9A and 9B and the constant voltage control circuits 10A and 10B to which such corrections have been applied,
Since the signals selected by the selection circuits 16A and 16B from the outputs of the constant margin angle control circuits 11A and 11B are already almost identical between the two control devices 4A and 4B, the dual system selection circuit The signals are input to the phase control circuits 19A and 19B without performing collation by such means. The phase control circuits 19A and 19B determine the timing of the gate pulse based on the timing, and the gate pulse generator 5 generates a gate signal based on the timing signal sent from the phase control circuits 19A and 19B to generate a thyristor converter. 2 is controlled.

As described above, in the two control devices 4A and 4B, the difference between the output values of the constant current control circuits 9A and 9B and the difference between the output values of the constant voltage control circuits 10A and 10B are determined by a constant having a large time constant. Correction control circuits 22A, 22 for current control circuit
B or correction control circuit 25A, 25 for constant voltage control circuit
Since the signals are fed back to the respective input units through B, the output values are corrected so as to be the same, so that it is not necessary to exchange the outputs of the two systems each time for collation, and there is no influence of the time delay. A stable control system can be realized.

In FIG. 1, the correction control circuits 22A and 22B for the constant current control circuit and the correction control circuits 25A and 25B for the constant voltage control circuit are described as first-order lag circuits, but control circuits other than the first-order lag are used. The same effect as described above may be obtained.

Embodiment 2 FIG. Next, another embodiment of the present invention will be described with reference to the drawings. FIG. 2 is a block diagram showing a configuration of a control device to which the control method for an AC / DC converter according to the second embodiment is applied. The same reference numerals as those in FIG. 1 denote corresponding parts, and a description thereof will be omitted. In the figure, reference numerals 31A and 31B denote parameters and initial values of constant current control circuits 9A and 9B based on a difference between output values of constant current control circuits 9A and 9B exchanged via transmission circuits 27 and 28. 32A and 32B are transmission circuit 2
This is a parameter correction circuit that corrects the parameters and initial values of the constant voltage control circuits 10A and 10B based on the difference between the output values of the constant voltage control circuits 10A and 10B that are exchanged between the constant voltage control circuits 9A and 10B. Note that the control devices 4A and 4B in the second embodiment are
1A, 31B and 32A, 32B,
1A, 21B, 23A, 23B, 24A, 24B, 26
A, 26B and correction control circuit 22 for constant current control circuit
A, 22B, correction control circuit 25A, 2 for constant voltage control circuit
5B is omitted from the first embodiment in which the same reference numerals are given in FIG. 1.

Next, the operation will be described. The two control devices 4A and 4B are connected to the outputs of the respective constant current control circuits 9A and 9B and the constant voltage control circuit 10 as in the first embodiment.
A, 10B are output to transmission circuits 27, 28, 29, 30
Are mutually exchanged through. In each of the control devices 4A and 4B, the output of the constant current control circuit 9A (9B) of its own device and the output of the constant current control circuit 9B (9A) of the partner device are input to the parameter correction circuits 31A and 31B, and the parameter correction circuit 32A and 32B have their own constant voltage control circuits 10A.
Output of (10B) and constant voltage control circuit 10B of the partner device
(10A) and the output. Parameter correction circuit 3
In 1A and 31B, when there is a difference between the output values of the two series of constant current control circuits 9A and 9B, the gain constants and time constants of the constant current control circuits 9A and 9B are corrected. Similarly, the parameter correction circuits 31A and 31B correct the gain constants and time constants of the constant voltage control circuits 10A and 10B when there is a difference between the output values of the two systems of constant voltage control circuits 10A and 10B. Thereby, the correction is made so that the output difference between the two control devices 4A and 4B becomes small.

The selection circuits 16A and 16B select from the corrected outputs of the constant current control circuits 9A and 9B and the constant voltage control circuits 10A and 10B and the outputs of the constant margin angle control circuits 11A and 11B. Since the signals are almost in agreement between the two control devices 4A and 4B, the signals are input to the phase control circuits 19A and 19B without performing the collation again, and the timing of the gate pulse is determined there. . This timing signal is sent to the gate pulse generator 5, and a gate signal based on the timing is output from the gate pulse generator 5 to control the thyristor converter 2.

As described above, the two control devices 4A and 4B control the constant current according to the difference between the output values of the constant current control circuits 9A and 9B and the difference between the output values of the constant voltage control circuits 10A and 10B. Circuits 9A and 9B and constant voltage control circuit 10
The parameters and initial values of A and 10B are changed, and the constant current control circuits 9A and 9B and the constant voltage control circuits 10A and 10A of both systems are changed.
Since the parameters of 10B and the deviation of the structure are corrected so that the output values of the two systems match each other, it is possible to construct a system having no problem even if the outputs of both systems are not exchanged and verified each time.

In the above embodiment, the gain constant and the time constant are shown as examples of the parameters to be corrected. However, the parameters of other components may be corrected.

Embodiment 3 FIG. Next, still another embodiment of the present invention will be described with reference to the drawings. FIG. 3 is a block diagram showing a configuration of a control device to which the control method of the AC / DC converter according to the third embodiment is applied. The same reference numerals as in FIG. 1 denote the corresponding parts, and a description thereof will be omitted. In the figure, reference numerals 33A and 33B denote determination circuits which take in both outputs of the constant current control circuits 9A and 9B exchanged via transmission circuits 27 and 28 and determine whether the system is normal or abnormal. , 34B
Are output contacts of the discriminating circuits 33A and 33B. 35
A and 35B are discriminating circuits which take in both outputs of the constant voltage control circuits 10A and 10B exchanged via the transmission circuits 29 and 30 and discriminate whether the system is normal or abnormal. These are output contacts of the discriminating circuits 35A and 35B. Note that these discriminating circuits 33A, 33B,
35A and 35B determine that one system is abnormal when the difference between the fetched output values is large, when one of them has no output, or when the output value is oscillating, etc.
4A, 34B, 36A and 36B are opened.
Note that the control devices 4A and 4B in the third embodiment include these discriminating circuits 33A and 33B and 35A and 35B,
This embodiment differs from the first embodiment in which output contacts 34A and 34B and 36A and 36B are provided with the same reference numerals in FIG.

Next, the operation will be described. Also in this case, as in the case of the first embodiment, the two control devices 4A and 4B output the outputs of the constant current control circuits 9A and 9B and the outputs of the constant voltage control circuits 10A and 10B to the transmission circuits 27 and 28, respectively.
They are mutually exchanged via 29 and 30. Each control device 4
In A and 4B, the output values of the exchanged constant current control circuits 9A and 9B are input to the adders 21A and 21B with opposite polarities, and also input to the discriminating circuits 33A and 33B. The outputs of the adders 21A and 21B are input to the constant current control circuit correction control circuits 22A and 22B having a large time constant, and the correction signals output from the constant current control circuit correction control circuits 22A and 22B are determined. Output contacts 34 of circuits 33A and 33B
A and 34B are input to the adders 23A and 23B.

On the other hand, in the discriminating circuits 33A and 33B, when the difference between the two output values inputted is large,
Further, it is determined whether the output is vibratory or the like.
A, 34B are opened, and the correction signals from the constant current control circuit correction control circuits 22A, 22B are added to adders 23A, 23B.
Avoid feedback. Therefore, the correction signals from the constant current control circuit correction control circuits 22A and 22B are input to the adders 23A and 23B only when the discrimination circuits 33A and 33B confirm that the signals are normal. Correction is performed accordingly.

Similarly, in each of the control devices 4A and 4B, the output values of the exchanged constant voltage control circuits 10A and 10B are input to the adders 24A and 24B with opposite polarities, and also input to the discriminating circuits 35A and 35B. The adders 24A, 24
The output of B is a correction control circuit 25A, 25 for a constant voltage control circuit.
B, and the correction signal is supplied to discrimination circuits 35A, 35B.
Adders 26A, 26B through output contacts 36A, 36B of
B is input. The discriminating circuits 35A and 35B discriminate between a case where the difference between the two output values input is large, a case where there is no output on one side, and a case where the output is oscillating. The output contact 36
A, 36B are opened, and the correction signals from the constant voltage control circuit correction control circuits 25A, 25B are added to adders 26A, 26B.
Avoid feedback. Therefore, only when the discrimination circuits 35A and 35B confirm that the signals are normal, the correction according to the difference between the output values of the two systems is performed.

As described above, in the two control devices 4A and 4B, the constant current control circuits 9A and 9B and the constant voltage control circuit 1
When the difference between the output values of 0A and 10B exceeds a specified value, or one of the systems becomes non-output, or an abnormal state occurs such as the output vibrates, the correction according to the difference between the output values of the two systems. Is stopped, it is possible to prevent a normal system from being corrected by trying to match both systems when one system is abnormal and outputting an outrageous output, and a normal control system can be maintained. Like that. Further, with this configuration, even when one system does not output due to a stop or an accident, it is possible to continue normal operation without affecting the other system.

Embodiment 4 FIG. Next, still another embodiment of the present invention will be described with reference to the drawings. FIG. 4 is a block diagram showing a configuration of a control device to which the control method of the AC / DC converter according to the fourth embodiment is applied. The same reference numerals as in FIG. 5 denote the corresponding parts, and a description thereof will be omitted. In the figure, 37A and 37B are storage circuits for storing the previous output values of the selection circuits 16A and 16B, and 38A and 38B are the selection circuits 16A and 16B.
Is a comparison circuit for comparing the previous output value with the current output value. 39A and 39B are switching circuits for switching the output of the selection circuits 16A and 16B according to the outputs of the comparison circuits 38A and 38B, and 40A and 40B are transmission circuits 17A and 1B according to the outputs of the comparison circuits 38A and 38B.
This is a double comparison circuit for comparing the output values of the selection circuits 16A and 16B exchanged with each other at 7B. The control devices 4A and 4B according to the fourth embodiment include a dual system selection circuit 18.
Instead of A, 18B, these storage circuits 37A, 37B,
In that it includes comparison circuits 38A and 38B, switching circuits 39A and 39B, and dual-system comparison circuits 40A and 40B.
This is different from the conventional one denoted by the same reference numeral in FIG.

Next, the operation will be described. Each control device 4
In A and 4B, the previous output values of the selection circuits 16A and 16B are stored in the storage circuits 37A and 37B. Comparison circuit 3
8A and 38B compare the current output values of the selection circuits 16A and 16B with the previous output values of the selection circuits 16A and 16B stored in the storage circuits 37A and 37B, and switch the switching circuit 39A according to the difference. , 39B and the duplex comparison circuits 40A, 40B. That is, if the difference is equal to or less than the set specified value, the switching circuits 39A and 39B
Is turned on, and the outputs of the selection circuits 16A and 16B of the own device are controlled independently of the output of the other device.
A, 19B. Further, the comparison circuits 38A and 38B
If the difference is determined to be greater than or equal to the specified value,
The output of the selection circuits 16B and 16A of the partner device is transmitted to the transmission circuit 1
7A and 17B, the two-system comparison circuits 40A and 40B confirm that the difference between the output values of the two systems is within a certain value, and then output the output value to the phase control circuit 19.
A, 19B.

As described above, since the selection operation is performed only by comparing the previous control output held by the own apparatus with the current control output, the difference between the current output and the previous output is specified in a normal state. If it is within the value, the output can be output as it is, the influence of the time delay for exchanging the control output on the control characteristics etc. can be eliminated, and a stable control system can be constructed. If an output greatly deviating from the value occurs, a decrease in reliability can be prevented by checking the output value of the partner device.

[0040]

As described above, according to the first aspect of the present invention, the amount corresponding to the difference between the output values of the control circuits such as the constant current control circuit and the constant voltage control circuit of the own device and the other device is calculated. Since feedback is provided to the input of the control circuit of the own device, correction is performed so that the difference between the output values of the respective control devices is reduced, and it is not necessary to exchange the output of each system every time and perform collation. In addition, it is possible to perform a stable control that is not affected by a time delay, and to obtain a control method of an AC / DC converter that can smoothly replace a healthy system even if one system becomes unavailable due to a failure or the like. There is.

According to the second aspect of the present invention, the configuration is such that the parameters of the control circuit of the own device are corrected in accordance with the difference between the output values of the control circuits of the own device and the other device.
In addition to correcting by adding a correction signal to the input of the control circuit, it is also possible to correct the configuration by correcting the parameter, thereby eliminating the deviation of the parameters and structure of the control circuit of each system, and every time Since there is no need to check the output of each system, there is an effect that a control method of the AC / DC converter capable of performing stable control without being affected by a time delay is obtained.

According to the third aspect of the present invention, only when the normality is confirmed by the discrimination based on the output values of the control circuits of the own device and the other device, the difference between the output values is determined. Since the amount is fed back to the input value of the control circuit of the own device, when one system is abnormal and sending out an outrageous output value, the normal system is corrected in accordance with the output value. There is an effect that a control method of the AC / DC converter that can always maintain the normality of the control system can be obtained.

According to the fourth aspect of the present invention, the control output is transmitted according to the result of comparison with the output value of the other device only when the difference between the previous output value and the current output value of the own device is equal to or greater than a specified value. Configuration, so that the decision is always made using the information of the own device, so that it is not affected by the time delay, and if the output value is significantly different from the previous value, the output value of the other device is checked. By doing so, there is an effect that a control method of the AC / DC converter that can secure the reliability can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention.

FIG. 2 is a block diagram showing a second embodiment of the present invention.

FIG. 3 is a block diagram showing a third embodiment of the present invention.

FIG. 4 is a block diagram showing a fourth embodiment of the present invention.

FIG. 5 is a block diagram showing a conventional device.

[Explanation of symbols]

4A, 4B control device, 9A, 9B control circuit (constant current control circuit), 10A, 10B control circuit (constant voltage control circuit).

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H02M 7/00-7/40

Claims (4)

(57) [Claims] 1. A control method of an AC / DC converter for controlling an AC / DC converter by a multiplexed control device, wherein the respective control devices exchange outputs of respective control circuits with each other, and the control circuits of the own device are exchanged. A method for controlling an AC / DC converter, comprising adding an amount corresponding to a difference between an output value and an output value of the control circuit of another device to an input value of the control circuit. 2. A control method of an AC / DC converter for controlling an AC / DC converter by a multiplexed control device, wherein the control devices exchange output values of respective control circuits with each other,
A method for controlling an AC / DC converter, comprising modifying parameters of the control circuit according to a difference between an output value of the control circuit of the own device and an output value of the control path of another device. 3. A control method of an AC / DC converter in which the AC / DC converter is controlled by a multiplexed control device, wherein the respective control devices exchange outputs of respective control circuits, and the control circuits of the own device are exchanged. Normal / abnormal of each of the control devices is determined based on the output value and the output value of the control circuit of the other device, and only when normality is confirmed by the determination, the output values of the own device and the other device are determined. A method for controlling an AC / DC converter, comprising adding an amount corresponding to a difference to an input value of the control circuit. 4. A control method for an AC / DC converter in which the AC / DC converter is controlled by a multiplexed control device, wherein each control device compares a previous output value of the own device with a current output value, If the difference between the two is within a specified value, the output value is immediately transmitted. If the difference is equal to or larger than the specified value, the output value is transmitted according to the result of comparison with the output value of another device. How to control the vessel.