JP3244919B2 - Control device 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 control device for an AC / DC converter used for DC interconnection equipment such as DC power transmission and frequency converter.

[0002]

2. Description of the Related Art In recent years, AC / DC converters used for DC interconnection equipment such as DC power transmission and frequency converters include basic control circuits for controlling DC voltage and DC current, such as constant current control and constant voltage control, and start / stop. As a control device including a circuit, a protection interlocking circuit, and a phase control circuit for determining a firing phase of a converter and performing a pulse operation, a shift has been made from a logic circuit using electronic circuits to a control system using software.

FIG. 7 shows one end of a control system of such an AC / DC converter, and a similar device is provided at the other end so that different AC systems are interconnected to exchange power. DC interconnection equipment is configured.

In FIG. 7, reference numeral 3 denotes a thyristor converter,
An input terminal or an output terminal of the thyristor converter 3 is connected to an AC system AC via an AC circuit breaker 1 and a converter transformer 2, and an output terminal or an input terminal is connected to a DC line DL via a DC reactor 4. ing.

[0005] The DC line DL is provided with a DC current transformer 5 for detecting a DC current and a DC transformer 6 for detecting a DC voltage. Further, an AC voltage detector 7 for detecting an AC voltage is connected to the AC system AC.

On the other hand, reference numeral 8 denotes a control device comprising microcomputer control and protection means 80 which is software-processed by a microcomputer (hereinafter abbreviated as a microcomputer), and 9 amplifies a phase control pulse PHS from the control device 8 and a gate pulse. This is a gate pulse generator that gives a signal to the gate of the thyristor of the pulse converter 3.

The microcomputer control protection means 8 of the control device 8
0 denotes a basic control circuit 83, a start / stop circuit 84 for starting / stopping while emphasizing a forward converter and an inverse converter, and a protection interlocking circuit 8 for protecting / stopping the converter in case of a main circuit accident.
5. It includes a synchronization detection circuit 82 and a phase control circuit 81 that output a phase signal synchronized with the AC voltage Vac detected by the AC voltage detector 7.

Here, the basic control circuit 83 includes the DC current transformer 5
, A constant current control circuit (hereinafter abbreviated as ACR) 830 for controlling the DC current Idc to be constant, a DC voltage Vdc detected by the DC transformer 6, and a DC current Idc. A constant voltage control circuit (hereinafter abbreviated as AVR) 831 for controlling the voltage Vdc to a constant value, an AC voltage Vac detected by the AC voltage detector 7 are input, and a margin angle of the thyristor converter 3 is fixed from the AC voltage Vac. Margin angle control circuit (hereinafter abbreviated as AγR) 832 and ACR830, AVR831, AγR
When the thyristor converter 3 is a forward converter, the output of the ACR 830 is selected when the thyristor converter 3 is a forward converter, and the output of the normal AVR 831 is selected when the thyristor converter 3 is an inverse converter.

The phase control circuit 81 includes a basic control circuit 8
3 has a function of outputting a phase control pulse PHSA to the gate pulse generator 9 based on the phase signal from the synchronization detection circuit 82 in accordance with the control angle α which is the output of 3.

The phase control circuit 81 has a phase control pulse PH
It has a function of converting S into a pulse suitable for starting and stopping the converter and for stopping the protection by a signal from the start / stop circuit 84 and the protection interlocking circuit 85.

When a protection request signal for stopping the thyristor converter 3 is input due to some accident, the protection interlocking circuit 85 sets the gate shift GS, the bypass pair BPP,
A function of selecting an appropriate one of the gate blocks GB for each accident and selecting a protection operation for protecting the thyristor converter 3, and then a gate shift GS and a bypass pair BP
It has a function of determining the interlocking time of P and the gate block GB and performing a stop operation for stopping the thyristor converter 3 safely.

FIG. 8A shows the protection interlocking circuit 85.
When the protection request signal is input, GS-BPP-GB-
A timing chart of the protection interlocking of the CBT is shown, and FIG. 2B is a timing chart of the protection interlocking of the BPP-GB-CBT.

FIG. 9 shows such microcomputer control protection means 8.
0 shows an example of the bus configuration of ACR830, AVR
CPU and memory 10 for realizing a basic control circuit 83 such as 831 and AγR832, a start / stop circuit 84, a protection interlocking circuit 84, and the like, and a phase control circuit 11, a synchronization detection circuit 12, and analogs such as Idc, Vdc, and Vac. Analog input conversion circuit 1 for converting signals to digital signals
3, an analog output conversion circuit 14 for converting a digital signal into an analog signal, a digital input circuit 15 for inputting a protection request signal and the like, and a digital output circuit 16 for outputting a circuit breaker trip signal CBT and the like.
7 are connected.

FIG. 10 shows a multiplex system control system in which the control system of the AC / DC converter is composed of a plurality of series of control systems, wherein the control system is a double system and the gate pulse generator is a single system. 7, the same components as those in FIG. 7 are denoted by the same reference numerals with suffixes A or B, and redundant description will be omitted.

The control devices 8A and 8B of FIG. 10 include an αA selection circuit 81A and an αB selection circuit 81B for performing cooperative control of the control angle α of the dual system control device. It is configured by adding to the same circuit as the system.

ΑA selection circuit 81A and αB selection circuit 8
1B is a circuit for selecting one of the control angles α of the A-system controller 8A and the B-system controller 8B. Normally, among the control angles of the respective control devices, the largest control angle is selected in the case of a forward converter, and the smaller one of the control angles is selected in the case of an inverse converter.

[0017]

In a control device of an AC / DC converter constituted by such a microcomputer control protection means, when a protection interlock circuit is realized by software, a time limit of an internal stop operation of the protection interlock can be easily set. There are merits such as being changeable. However, due to the dead time caused by the calculation time, the protection relay operates as shown in FIG. 11, and the protection relay of the control device forms a DC current waveform such as an A waveform to be protected. Since a DC overcurrent such as a B waveform is promoted depending on time and cannot be protected, the thyristor converter cannot be stopped safely and may be damaged.

Further, the microcomputer runs out of control due to some abnormality. For example, when the thyristor converter 3 is operated by the inverter, the memory realizing the protection interlock becomes abnormal, and the circuit breaker trip command CBT is output. In this case, since the converter has no energy output destination, the energy is charged in the capacitance component of the device, and there is a possibility that the thyristor converter is damaged due to a DC overvoltage.

Therefore, if a constant monitoring function is provided to lock the output of the microcomputer by detecting runaway of the microcomputer, the phase control pulse PHS is not output as a result, and the pulse applied to the converter is locked. The DC current, DC voltage, and AC voltage as shown in FIG. 12 are generated, and the thyristor converter cannot be stopped safely and may be damaged. Further, even if the circuit breaker is opened, there is a possibility that direct current interruption may occur, and conversely, the circuit breaker may be damaged.

If the control protection means is constituted only by a microcomputer as described above, the equipment cannot be protected due to the dead time caused by the calculation time, and the main circuit may be damaged, or the main circuit may be damaged due to the abnormality of the microcomputer. It may lead to a serious accident expansion.

An object of the present invention is to prevent an unnecessary signal from being output at the time of a microcomputer runaway or an unnecessary stop of a converter due to a delay of a protection operation, and to prevent a main circuit such as an AC circuit breaker and a thyristor converter from being output. It is an object of the present invention to provide a control device for an AC / DC conversion device that can prevent an accident leading to damage beforehand.

[0022]

According to the present invention, a control device for an AC / DC converter is constituted by the following means to achieve the above object. The invention corresponding to claim 1 is:
A phase control pulse is output by determining a firing phase of the converter based on a control signal for controlling a DC voltage or a DC current of a main circuit, and the phase control pulse is converted into a gate pulse and supplied to the converter. In a control device of an AC / DC conversion device such as a power transmission device or a frequency conversion device, when a protection request signal is input from outside, a protection interlocking time period for calculating a protection operation signal to stop or start protection of the converter can be changed. A first protection interlocking means by a microcomputer, a second protection interlocking means by an electronic circuit for outputting a protection operation signal to stop the converter at a high speed when a protection request signal is input from the outside, and an external signal Has a function capable of performing a pulse operation by inputting a signal, determines the ignition phase of the converter and performs the pulse operation, and performs the first protection interlocking means and the second protection interlocking means. The protection protective operation signal protection operation signal from the interlock means is input from the second protective interlocking means to be inputted respectively, protected stopping the converter converts the phase control pulse to a pulse suitable for the protective stop A phase control unit; and an output locking unit that locks an output of an unnecessary signal in cooperation with the second protection interlocking unit when the first protection interlocking unit is abnormal.

According to a second aspect of the present invention, a firing phase of a converter is determined based on a control signal for controlling a DC voltage or a DC current of a main circuit, a phase control pulse is output, and the phase control pulse is output. In a control device of an AC / DC converter, such as a DC power supply or a frequency converter, which converts the signal into a gate pulse and gives it to the converter, when a protection request signal is input from the outside, a protection operation is performed to stop or stop the converter. A first protection interlocking means by a microcomputer capable of changing a protection interlocking time limit for calculating and outputting a signal;
Second protection interlocking means comprising an electronic circuit configured to output a protection operation signal to stop protection of the converter at high speed when a protection request signal is input from the outside and a protection request signal is input from the outside; Protection interlocking means for outputting a logical product or a logical sum of the protection operation signals output from the two protection interlocking means, and a function capable of performing a pulse operation by inputting an external signal, and firing the converter. When the determination of the phase and the pulse operation are performed and a protection operation signal obtained by ANDing or ORing the outputs of the first protection interlocking means and the protection interlocking coordination means is input, the protection interlocking coordination means is protected. by the operation signal, a phase control means for protecting stops the converter converts the phase control pulse to a pulse suitable for the protective stop the protective interlock coordination when abnormality of the first protective interlocking means And an output lock means for locking an unnecessary signal outputted from said first protection interlocking means taking a logical product of the output signal of the stage.

According to a third aspect of the present invention, a starting phase of a converter is determined based on a control signal for controlling a DC voltage or a DC current of a main circuit, a phase control pulse is output, and the phase control pulse is output. In a control device of an AC / DC converter, such as a DC power supply or a frequency converter, which converts the signal into a gate pulse and gives it to the converter, when a protection request signal is input from the outside, a protection operation is performed to stop or stop the converter. A first protection interlocking means comprising a microcomputer capable of changing a protection interlocking time for obtaining a signal by operation, and an electronic device for outputting a protection operation signal to stop the converter at high speed when a protection request signal is inputted from outside. 2nd by circuit
Protection interlocking means, and a function capable of performing a pulse operation by inputting an external signal, determining the firing phase of the converter and performing the pulse operation, and the first protection interlocking means and the second protection When the protection operation signal is input from the interlocking means, respectively, the protection operation signal input from the second protection interlocking means converts the phase control pulse into a pulse suitable for the protection stop and the phase for stopping the protection of the converter. A plurality of converter control devices are provided, each including a control means, and an output lock means for locking an output of an unnecessary signal in cooperation with the second protection interlocking means when the first protection interlocking means is abnormal. A multiplex system control device is provided, and a monitoring means for monitoring the control state of the converter control devices of each series and a monitoring coordination means for coordinating the monitoring results of the monitoring means among the systems are provided. When the converter controller of one series becomes abnormal by the monitoring coordination means, the output pulse of the converter controller in the abnormal state is locked on condition that the converter controllers of the other series are normal, and When the converter control device of another system is disconnected, the converter is protected by the second protection interlocking means of the converter control device in the abnormal state.

According to a fourth aspect of the present invention, a firing phase of a converter is determined based on a control signal for controlling a DC voltage or a DC current of a main circuit, a phase control pulse is output, and the phase control pulse is output. In a control device of an AC / DC converter, such as a DC power supply or a frequency converter, which converts the signal into a gate pulse and gives it to the converter, when a protection request signal is input from the outside, a protection operation is performed to stop or stop the converter. A first protection interlocking means of a microcomputer capable of changing a protection interlocking time for calculating a signal, and a part for outputting a protection operation signal to stop the converter at high speed when a protection request signal is input from the outside; Unnecessary operation is prevented by coordinating the output signal of the second protection interlocking means by the duplicated electronic circuit and the output signal of the second protection interlocking means partially duplicated. A main operation prevention means, with has a pulse operation is capable of functioning by the input of an external signal, and makes a decision and pulse operation of ignition phase point of said transducer, said first
When a protection operation signal obtained from the protection interlocking means and the unnecessary operation prevention means is input , a phase control signal is input by the protection operation signal input from the unnecessary operation prevention means.
And phase control means for protecting stops the transducer converts the pulse into a pulse suitable for the protective stop, the output of the unwanted signal by taking coordination with the unnecessary operation preventing means when a failure of the first protection interlocking means A plurality of rows of converter controllers each having an output lock unit for locking the control unit, a multiplex control unit is configured, and a monitoring unit that monitors a control state by the converter control units of each series and a monitoring result of the monitoring unit are provided. A monitoring coordination means for coordinating between the systems is provided. If the monitoring means and the monitoring coordination means cause an abnormality in the converter control device of one system, the converter control devices of the other system are normal. The output pulse of the converter controller in the abnormal state is locked, and the duplexed second controller controller in the abnormal state is locked when other series of converter controllers are disconnected. Protection interlock The protective operation signal obtained from the unnecessary operation prevention means stage is obtained so as to protect the transducer.

[0026]

In the configuration of the invention corresponding to claim 1, a protection request signal is input to the control device to the first protection interlocking means by calculation and to the second protection interlocking means operable at high speed by an electronic circuit. When, the protective operation signal faster than a second protective interlock means are provided to pulse operation possible phase control means by an external signal, the protection operation signal by the phase control means
Thus, it is possible to convert the phase control pulse into a pulse suitable for the protection stop and stop the protection of the converter, and it becomes impossible to protect the converter due to a delay in the protection operation, and the main circuit including the converter is damaged. This can be prevented beforehand.

When an abnormality occurs in the first protection interlocking means, the output of an unnecessary signal is locked in cooperation with the second protection interlocking means, so that the converter is stopped unnecessarily. No more.

According to a second aspect of the present invention, in addition to the functions and effects of the first aspect of the present invention,
Since the second protection interlocking means is duplicated and the logical operation or the logical sum of the protection operation signals output from each of the second protection interlocking means is taken to cooperate with the protection interlocking, unnecessary operation of the second protection interlocking means can be prevented. In addition, the gate pulse of the converter is not pulse-locked, and the AC / DC converter can be safely stopped.

In the configuration of the invention corresponding to claim 3, the converter control device of the configuration of the invention corresponding to the first claim is provided as a multiplex configuration in the converter control device of each stream. The monitoring means for monitoring the control state and the monitoring and coordination means for coordinating the monitoring results of the monitoring means among the systems,
When the converter controller of one system becomes abnormal, the output pulse of the converter controller in an abnormal state is locked on condition that the converter controller of the other system is normal, and the conversion of the other system is performed. When the converter controller is disconnected, the converter is protected by the second protection interlocking means of the converter controller in an abnormal state, so that the characteristics of the multiplex control system are not impaired, and Even if one of the converter control devices becomes abnormal, the AC / DC converter can be safely stopped without pulse-locking the gate pulse of the converter, and the protection operation can be performed at high speed.

In the structure of the invention corresponding to claim 4, in addition to the operation and effect of the invention corresponding to claim 3,
Since the converter is protected by the protection operation signal obtained through the unnecessary operation preventing means from the duplicated second protection interlocking means, unnecessary operation of the second protection interlocking means can be prevented.

[0031]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment of a control device for an AC / DC converter according to the present invention.
In the circuit configuration diagram showing the embodiment, the same parts as those in FIG.

In FIG. 1, reference numeral 3 denotes a thyristor converter,
An input terminal or an output terminal of the thyristor converter 3 is connected to an AC system AC via an AC circuit breaker 1 and a converter transformer 2, and an output terminal or an input terminal is connected to a DC line DL via a DC reactor 4. ing.

The DC line DL is provided with a DC current transformer 5 for detecting a DC current and a DC transformer 6 for detecting a DC voltage. Further, an AC voltage detector 7 for detecting an AC voltage is connected to the AC system AC.

On the other hand, 8 is a control device comprising microcomputer control protection means 80 which is software-processed by a microcomputer, and 9 is a thyristor of the pulse converter 3 which amplifies the phase control pulse PHSA from the control device 8 and generates a gate pulse signal. Is a gate pulse generator applied to the gate of the gate.

The control device 8 includes a basic control circuit 83, a start / stop circuit 84 for starting / stopping while coordinating the forward converter and the inverse converter, and a first protection / protection stop for the converter in case of a main circuit accident. Protection interlock circuit 85, AC voltage detector 7
Microcomputer protection protection means 80 including a synchronization detection circuit 82 for outputting a phase signal synchronized with the AC voltage Vac detected by the microcomputer and a phase control device 100 with an external interrupt function, and a first protection interlock of the microcomputer control protection means 80 Second protection interlocking circuit 1 by an electronic circuit provided separately from the circuit
01 and an AND circuit 102.

Here, the basic control circuit 83 is a DC current transformer 5
, A constant current control circuit (hereinafter abbreviated as ACR) 830 for controlling the DC current Idc to be constant, a DC voltage Vdc detected by the DC transformer 6, and a DC current Idc. A constant voltage control circuit (hereinafter abbreviated as AVR) 831 for controlling the voltage Vdc to a constant value, an AC voltage Vac detected by the AC voltage detector 7 are input, and a margin angle of the thyristor converter 3 is fixed from the AC voltage Vac. Margin angle control circuit (hereinafter abbreviated as AγR) 832 and ACR830, AVR831, AγR
When the thyristor converter 3 is a forward converter, the output of the ACR 830 is selected when the thyristor converter 3 is a forward converter, and the output of the normal AVR 831 is selected when the thyristor converter 3 is an inverse converter.

As shown in FIG. 2, the phase control device 100 includes a phase control circuit 81 to which the control angle α output from the basic control circuit 83 and the converter start / stop command DEB from the start / stop circuit 84 are input. , The gate shift GS ₀ , the bypass pair BPP ₀ from the first protection interlocking circuit 85, and the gate shift GS ₁ , the bypass pair BPP ₁ , the gate block GB from the gate block GB ₀ and the second protection interlocking circuit 101.
₁ and are inputted respectively, and a logic circuit 100a for inputting gate shift GS ₁ from the second protective interlock circuit 101, a bypass pair BPP _1, the gate block GB ₁ to the phase control circuit 81.

The logic circuit 100a includes gate shifts GS ₀ and GS ₁ , bypass pairs BPP ₀ and BPP ₁ ,
AND circuits that respectively take the AND condition of the gate blocks GB ₀ and GB ₁ , outputs of the respective AND circuits, a gate shift GS ₁ from the second protection interlocking circuit 101, a bypass pair BPP ₁ , and signals of the gate block GB ₁ And an OR circuit that takes the OR condition of

The phase control circuit 81 includes the basic control circuit 8
3: a function of outputting a phase control pulse PHSA to the gate pulse generator 9 based on the phase signal from the detection circuit 82, and a function of outputting the phase control pulse PH
It has a function of converting SA into a pulse suitable for the protection operation of the converter by a signal of the second protection interlocking circuit 101.

The first protection interlocking circuit 85 by the microcomputer and the second protection interlocking circuit 101 by the electronic circuit are provided with a gate shift GS and a bypass when a protection request signal for stopping the thyristor converter 3 is inputted due to some accident. A function of selecting a protection operation for protecting the thyristor converter 3 by selecting an appropriate one for each accident from the pair BPP and the gate block GB, and then interlocking time of the gate shift GS, the bypass pair BPP and the gate block GB. And a function of performing a stop operation for safely stopping the thyristor converter 3 is provided.

Further, the AND circuit 102 provides an AND condition between the circuit breaker trip command CBT ₀ output from the first protection interlock circuit 85 and the circuit breaker trip command CBT ₁ output from the second protection interlock circuit 101 by the microcomputer. Is satisfied, a trip signal is output to the circuit breaker 1.

Next, the operation of the control device of the AC / DC converter according to the first embodiment thus configured will be described. Now, when the control device 8 operates the thyristor converter 3 as a forward converter or an inverse converter via the gate pulse generator 9, when the protection request signal is input to the control device 8, the microcomputer control protection means 80. First protection interlocking circuit 8
5 operates a second protection interlocking circuit 101 by an electronic circuit provided separately. These first and second protection interlock circuits 85 and 101 select a protection interlock corresponding to the protection request signal, and a pulse operation signal for stopping the converter in the phase control device 100, and gate shifts GS ₀ and GS _1. , Bypass pair BPP ₀ , BPP ₁ , gate block G
And it outputs the respective signals B _0, GB _1.

In the phase control device 100, as shown in FIG. 2, a second protection interlocking circuit 10 is
Gate shift GS ₁ input from ₁ and bypass pair B
PP _1, what the deviation of the signals of the gate block GB ₁ is first
Is input to the phase control circuit 85 faster than the signal input from the protection interlocking circuit 85. Thereby, the phase control circuit 10
0 performs the protection operation at high speed, so the protection operation is first performed by the output of the second protection interlocking circuit 101.

Next, when the output signals of the first protection interlocking circuit 85 and the second protection interlocking circuit 101 satisfy the AND condition in the logic circuit 100a, and the pulse operation signal is input to the phase control circuit 81, the phase control The circuit 81 performs a stop operation of the converter.

On the other hand, when the protection request signal is input to the control device 80 when the first protection interlocking circuit 85 by the microcomputer is in an abnormal state, the second protection interlocking circuit 101 by the electronic circuit
The protection operation and the stop operation of the thyristor converter 3 are performed by the pulse operation signal input to the phase control device 100 as described above.

The first protection interlocking circuit 85 and the second protection interlocking circuit 85
The circuit breaker trip command signals CBT ₀ and CBT ₁ output from the protection interlocking circuit 101 are coordinated by the AND circuit 102 and a trip command is issued to the circuit breaker 1 only when the AND condition is satisfied. Even if the first protection interlocking circuit 85 is abnormal, output of an unnecessary signal is prevented.

Therefore, it is possible to prevent the gate pulse from being pulse-locked, and it is possible to safely stop the AC / DC converter without causing the device to be damaged by outputting an unnecessary signal.

FIG. 3 is a block diagram showing the configuration of the second embodiment of the present invention. Components similar to those shown in FIG. 1 are denoted by the same reference numerals and description thereof will be omitted. In the second embodiment, the second protection interlocking circuit based on the electronic circuit in the first embodiment is partially duplicated to prevent unnecessary operation. That is, as shown in FIG. 3, the second protection interlocking circuits 101A1 and 101A made of a duplicated electronic circuit.
A2, each second protection interlocking circuit 101A1, 101A
A2, a protection request signal is input to A2, and the protection operation signal and circuit breaker trip command signal output from these second protection interlocking circuits 101A1 and 101A2 are transmitted to the coordinating circuit 1
And the protection operation signal output from the coordination circuit 103 is input to the phase control device 100, and the circuit breaker trip command signal is sent to the AND circuit 102 together with the circuit breaker trip command signal from the first protection interlocking circuit 85. Configuration.

When the AC / DC conversion system is a system in which operation priority is given to the AC / DC conversion system, as shown in FIG.
Gate shift GS _11, GS ₁₂ of A1,101A2, bypass pair BPP _11, BPP _12, gate block GB _11,
GB ₁₂ , circuit breaker trip command signal CBT ₁₁ , CBT ₁₂
And the output of the second protection interlocking circuit is obtained.

In the case where the AC / DC conversion system is a system giving priority to stoppage, the second protection interlocking circuits 101A1 and 101A2 using the duplicated electronic circuit as shown in FIG. 4B.
Gate shift GS ₁₁ , GS ₁₂ , bypass pair BP
The OR condition of P ₁₁ , BPP ₁₂ , gate blocks GB ₁₁ , GB ₁₂ , and circuit breaker trip command signals CBT ₁₁ , CBT _{12 is used} as the output of the second protection interlocking circuit.

Therefore, if the second embodiment is constructed, the same operation and effect as those of the first embodiment can be obtained, and unnecessary operation of the protection interlocking circuit by the electronic circuit can be prevented. Can be prevented from being pulse-locked, and the AC / DC converter can be safely stopped.

FIG. 5 is a block diagram showing the configuration of the third embodiment of the present invention. In the third embodiment, the first embodiment is applied to a dual control system constituted by two systems of control devices. The same components as those in FIG. A duplicate description will be omitted.

FIG. 5 is different from FIG. 8 in that phase control devices 100A and 100B with an external interrupt function, second protection interlocking circuits 101A and 101B using electronic circuits, and
Circuits 102A and 102B, microcomputer abnormality detection circuit 104
A, 104B, microcomputer abnormality coordination circuit 105A, 105
B is a newly added point.

In FIG. 5, the microcomputer abnormality detection circuit 10
4A and 104B, the failure signal detected by the A-system controller 8A
The microcomputer abnormality coordination circuits 105A and 105B perform cooperative control between the A-system control device 8B and the B-system control device 8B. When the microcomputer of the device 8B becomes abnormal, the pulse of the B-system control device 8B is locked.
If the microcomputer of the B-system control device 8B becomes abnormal while the A-system control device 8A has already been disconnected from the system for some reason, the second protection interlocking by the electronic circuit without locking the pulse is performed. The protection-linked pulse operation by the circuit 101B is output to the phase control device 100B, and a phase control pulse for stopping the thyristor converter 3 is output.

According to the third embodiment having such a structure,
It is possible to safely stop the AC / DC converter and perform a high-speed protection operation without impairing the features of the conventional dual system control system and without locking the gate pulse even when the microcomputer is abnormal.

FIG. 6 is a block diagram showing the configuration of the fourth embodiment of the present invention. The fourth embodiment is different from the third embodiment by 2
The present embodiment is applied to a dual system control system constituted by a series converter control device, and the same components as those in FIG.

FIG. 6 is different from FIG. 3 in that phase control devices 100A and 100B with an external interrupt function, second protection interlocking circuits 101A and 101B by electronic circuits, and
Circuits 102A and 102B, microcomputer abnormality detection circuit 104
A, 104B, microcomputer abnormality coordination circuit 105A, 105
B is a newly added point.

According to the fourth embodiment having such a structure,
A protection interlocking circuit with an electronic circuit that safely stops the AC / DC converter and enables high-speed protection operation without impairing the features of the conventional dual system control system and without locking the gate pulse even when the microcomputer is abnormal. Unnecessary operation of can be prevented.

[0059]

As described above, according to the present invention, an AC circuit breaker or a thyristor does not output an unnecessary signal at the time of microcomputer runaway and does not needlessly stop the converter due to a delay in protection operation. It is possible to provide a control device for an AC / DC converter that can prevent an accident that may lead to damage to a main circuit such as a converter.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of a control device of an AC / DC converter according to the present invention.

FIG. 2 is a circuit diagram showing a configuration of a phase control device in the embodiment.

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

FIG. 4 is a logic circuit diagram for coordinating a second protection interlocking circuit having a duplex configuration in the embodiment.

FIG. 5 is a block diagram showing a third embodiment of the present invention.

FIG. 6 is a block diagram showing a fourth embodiment of the present invention.

FIG. 7 is a block diagram showing a control device of a conventional AC / DC converter.

FIG. 8 is a block diagram showing a bus configuration of a microcomputer of the control device.

FIG. 9 is a diagram showing a time chart of a protection interlocking operation of the control device.

FIG. 10 is a block diagram showing a control device of a conventional duplex AC / DC converter.

FIG. 11 is a DC current waveform diagram showing the protection interlocking operation according to the first embodiment of the present invention and the conventional protection interlocking operation in comparison.

FIG. 12 is a diagram showing current and voltage waveforms of various parts when a control device using a conventional microcomputer has an abnormality.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Breaker, 2 ... Transformer transformer, 3 ... Thyristor converter, 4 ... DC reactor, 5 ... DC current transformer, 6 ... DC transformer, 7 ... AC voltage detector, 8 ...
Control device, 81: microcomputer control protection means, 82: synchronization detection circuit, 83: basic control circuit, 84: start / stop circuit, 85: first protection interlocking circuit, 9: gate pulse generator, 100 phase control device, 100a logic circuit, 101 second protection interlocking circuit, 102
... AND circuit.

Claims (4)

(57) [Claims] 1. A method for determining a firing phase of a converter based on a control signal for controlling a DC voltage or a DC current of a main circuit, outputting a phase control pulse, and converting the phase control pulse into a gate pulse. In a control device of an AC / DC conversion device such as a DC power transmission or a frequency conversion device to be applied to a converter, when a protection request signal is input from outside, a protection interlocking operation for calculating a protection operation signal to stop or start the protection of the converter is performed. A first protection interlocking means using a microcomputer whose time limit can be changed, and a second protection interlocking means using an electronic circuit which outputs a protection operation signal to stop the converter at high speed when a protection request signal is input from outside. Means for performing pulse operation by inputting an external signal, determining the ignition phase of the converter and performing the pulse operation, and the first protection interlocking means. And when a protection operation signal is input from the second protection interlocking means , the phase control pulse is converted into a pulse suitable for protection stop by the protection operation signal input from the second protection interlocking means. A phase control means for stopping the protection of the converter by means of the first protection interlocking means, and an output locking means for locking an output of an unnecessary signal in cooperation with the second protection interlocking means when the first protection interlocking means is abnormal. A control device for an AC / DC conversion device, characterized in that: 2. A method for determining a firing phase of a converter based on a control signal for controlling a DC voltage or a DC current of a main circuit, outputting a phase control pulse, and converting the phase control pulse into a gate pulse to generate a gate pulse. In a control device of an AC / DC conversion device such as a DC power transmission or a frequency conversion device applied to a converter, when a protection request signal is input from the outside, a protection operation signal is calculated and output to stop and stop the conversion of the converter. A first protection interlocking means using a microcomputer whose protection interlocking time can be changed; and a protection operation signal for stopping protection of the converter at a high speed when a protection request signal is inputted from the outside and a protection request signal is inputted from outside. The second protection interlocking means by the output electronic circuit and the logical product or the logical sum of the protection operation signals output from the second protection interlocking means of the duplex configuration are output. Protection interlocking means, and a function capable of performing a pulse operation by inputting an external signal, determining the ignition phase of the converter and performing the pulse operation, and the first protection interlocking means and the protection interlocking coordination. When the protection operation signal obtained by ANDing or ORing the outputs of the means is input, the protection operation signal of the protection interlocking coordination means is inputted .
The logical product of the phase control means for converting the phase control pulse into a pulse suitable for protection stop and stopping the converter for protection and the output signal of the protection interlock coordination means when the first protection interlock means is abnormal. And an output locking means for locking unnecessary signals output from the first protection interlocking means. 3. A phase control pulse is output by determining a firing phase of a converter based on a control signal for controlling a DC voltage or a DC current of a main circuit, and the phase control pulse is converted into a gate pulse to convert the phase control pulse into a gate pulse. In a control device of an AC / DC conversion device such as a DC power transmission or a frequency conversion device to be applied to a converter, when a protection request signal is input from outside, a protection interlocking operation for calculating a protection operation signal to stop or start the protection of the converter is performed. A first protection interlocking means using a microcomputer whose time limit can be changed, and a second protection interlocking means using an electronic circuit which outputs a protection operation signal to stop the converter at high speed when a protection request signal is input from outside. Means, having a function capable of pulse operation by input of an external signal, and determining the ignition phase of the converter and pulse operation,
When a protection operation signal is input from each of the first protection interlocking means and the second protection interlocking means , a phase control signal is input by the protection operation signal input from the second protection interlocking means.
And phase control means for protecting stops the transducer converts the pulse into a pulse suitable for the protective stop unwanted signal taking coordination with the second protective interlocking means when abnormality of the first protective interlocking means A plurality of rows of converter controllers each having an output lock unit for locking the output of the control unit, a multiplex system control unit is configured, and a monitoring unit that monitors the control state of the converter control unit of each system and a monitor of the monitoring unit A monitoring coordination means for coordinating the results among the systems is provided. When the monitoring means and the monitoring coordination means cause an abnormality in the converter control device of one system, it is determined that the converter control devices of the other system are normal. Locking the output pulse of the converter controller in the abnormal state to the condition, and the second protection interlock of the converter controller in the abnormal state when another series of converter controllers are disconnected. By means Control device for AC-DC converter, characterized in that to protect the serial converter. 4. A phase control pulse is output by determining a firing phase of a converter based on a control signal for controlling a DC voltage or a DC current of a main circuit, and the phase control pulse is converted into a gate pulse to output the phase control pulse. In a control device of an AC / DC conversion device such as a DC power transmission or a frequency conversion device to be applied to a converter, when a protection request signal is input from outside, a protection interlocking operation for calculating a protection operation signal to stop or start the protection of the converter is performed. A first protection interlocking means using a microcomputer whose time limit can be changed, and a partially duplicated electronic circuit for outputting a protection operation signal for stopping the protection at high speed when a protection request signal is input from the outside; A second protection interlocking means, an unnecessary operation prevention means for preventing unnecessary operation by coordinating the output signals of the partially duplicated second protection interlocking means, and an external signal. A pulse operation by inputting a signal, determines a firing phase of the converter and performs a pulse operation, and a protection operation signal obtained from the first protection interlocking means and the unnecessary operation prevention means. Are respectively input, the protection operation signal input from the unnecessary operation prevention means converts the phase control pulse into a pulse suitable for the protection stop, and the phase control means for stopping the protection of the converter; A plurality of converter control devices including output lock means for locking the output of unnecessary signals in cooperation with the unnecessary operation prevention means when the protection interlocking means is abnormal, to constitute a multiplex control apparatus, A monitoring means for monitoring the control state of the converter controller of the system and a monitoring coordination means for coordinating the monitoring results of the monitoring means between the systems are provided. When the converter controller of one series becomes abnormal, the output pulse of the converter controller in the abnormal state is locked on condition that the converter controllers of the other series are normal, and the other series of converter controllers are locked. When the converter control device is disconnected, the converter is protected by the protection operation signal obtained from the unnecessary operation prevention means of the duplicated second protection interlocking means of the converter control device in the abnormal state. A control device for an AC / DC converter, comprising: