CN109888718B

CN109888718B - Direct current field equipment control system and method

Info

Publication number: CN109888718B
Application number: CN201910167926.2A
Authority: CN
Inventors: 安海清; 李振动; 贺俊杰; 刘亚新; 王珣; 李金卜; 田凯哲; 张晓飞; 金海望; 吴淘; 岳娜; 柳杨; 翟永尚; 滕孟锋; 董海飞; 余黎明; 刘宪辉; 刘海勇; 李涛; 赵凯曼
Original assignee: State Grid Corp of China SGCC; Maintenance Branch of State Grid Jibei Electric Power Co Ltd
Current assignee: State Grid Corp of China SGCC; Maintenance Branch of State Grid Jibei Electric Power Co Ltd
Priority date: 2019-03-06
Filing date: 2019-03-06
Publication date: 2021-07-30
Anticipated expiration: 2039-03-06
Also published as: CN109888718A

Abstract

The invention provides a system and a method for controlling direct current field equipment, wherein the scheme comprises the following steps: the direct current station control device acquires the position state of the primary equipment and the running state of the direct current protection device, and sends a control instruction to the primary equipment. The workstation monitors the position state of the primary equipment and the running state of the direct current protection device. And the primary equipment regulates and controls the position state according to the control instruction. Under the condition that a line has a fault, the direct-current protection device regulates and controls each polar line breaker on the direct-current bus. Based on the scheme, the operating condition of the direct current field equipment can be monitored in real time through the workstation, so that the occurrence position of the fault can be known in real time, the operation of the direct current field equipment can be rapidly regulated and controlled based on the direct current station control device and the direct current protection device, the fault can be timely solved or stopped in advance, the damage of the direct current field equipment is avoided, and the working efficiency and the economic benefit of the converter station are greatly improved.

Description

Direct current field equipment control system and method

Technical Field

The invention relates to the technical field of electrical overhaul, in particular to a direct current field equipment control system and a direct current field equipment control method.

Background

With the proposal of the global energy internet concept, the demand for power generation and grid connection of renewable energy sources such as wind energy, solar energy and the like is higher and higher. However, these renewable energy power generation sources are intermittent and uncertain, resulting in the inability of conventional ac grids to properly scale. The flexible direct current transmission technology can flexibly control active power and reactive power and can supply power to a weak alternating current system, and the optimal selection of new energy power generation grid connection and remote transmission is achieved. The flexible direct current transmission adopts a true bipolar structure, and the direct current equipment in the flexible high-voltage converter station is numerous and has higher manufacturing cost compared with the traditional direct current transmission. Furthermore, a failure of the dc field equipment may cause a shutdown of the entire converter station, thereby affecting the normal operation and economic efficiency of the entire flexible dc grid.

At present, fault monitoring of existing flexible converter station direct current field equipment is manual on-site inspection and troubleshooting, which needs manual on-site troubleshooting, and manual on-site control operation is performed on each direct current equipment. Therefore, if a plurality of direct current field devices have faults, the efficiency of field troubleshooting and maintenance cannot effectively complete the fault processing task in time, so that the direct current field devices are damaged, and the working efficiency and the economic benefit of the converter station are greatly influenced.

Disclosure of Invention

In view of this, embodiments of the present invention provide a system and a method for controlling a dc field device, so as to solve the problem that a fault processing task cannot be timely and effectively completed, resulting in damage to the dc field device.

In order to achieve the above purpose, the embodiments of the present invention provide the following technical solutions:

the first aspect of the embodiments of the present invention discloses a dc field device control system, which includes:

the system comprises a direct current station control device, a work station, primary equipment and a direct current protection device;

the direct current station control device is used for acquiring the position state of the primary equipment and the running state of the direct current protection device and sending a control instruction to the primary equipment;

the workstation is connected with the direct current station control device and used for monitoring the position state of the primary equipment and the running state of the direct current protection device;

the primary equipment is connected with the direct current station control device and used for regulating and controlling the position state according to the control instruction;

the direct current protection device is connected with the direct current station control device and used for regulating and controlling each polar line breaker on the direct current bus under the condition that a line has a fault.

Preferably, in the dc field device control system, the workstation is connected to the dc station control apparatus through a first switch, and the workstation is configured to receive, through the first switch, the position state of the primary device and the operating state of the dc protection apparatus uploaded by the dc station control apparatus in real time, and monitor the position state of the primary device and the operating state of the dc protection apparatus.

Preferably, in the dc field device control system, the dc station control device is connected to the primary device through an interface device, and the dc station control device is configured to obtain a position state of the primary device in real time based on the interface device and send a control instruction to the corresponding primary device.

Preferably, in the above dc field device control system, the interface means includes:

the direct current field station control interface device is connected with the direct current station control device through a second switch, and is used for acquiring the position state of the primary equipment, sending the position state to the direct current station control device and forwarding a control instruction sent by the direct current station control device to the corresponding primary equipment;

and/or the presence of a gas in the gas,

the bipolar area direct current field interface device is connected with the direct current station control device through the second switch, and is used for acquiring the position state of the primary equipment, sending the position state to the direct current station control device, and forwarding a control instruction sent by the direct current station control device to the corresponding primary equipment;

and/or the presence of a gas in the gas,

the alternating current energy consumption device is connected with the direct current station control device through the second switch, and the alternating current energy consumption device is used for connecting energy consumption equipment in the primary equipment into the direct current bus when the load power of the direct current line is larger than a first threshold value, disconnecting the energy consumption equipment from the direct current bus when the surplus power consumed by the energy consumption equipment causes the load power of the direct current line to be smaller than a second threshold value, and the second threshold value is smaller than the first threshold value.

Preferably, in the dc field device control system, the dc protection device is connected to the dc station control device through a third switch, and the dc protection device is configured to send the switching state of each polar line breaker on the line to the dc station control device through the third switch.

Preferably, in the dc field device control system, the dc protection device includes:

a DC bus protection sub-device and a DC line protection sub-device;

the direct-current bus protection sub-device is connected with the direct-current station control device through a third switch, and is used for sending the switching-on/off state of each polar line breaker on the direct-current bus to the direct-current station control device and regulating and controlling each polar line breaker when a line fault or the polar line breaker fails;

the direct-current line protection sub-device is connected with the direct-current bus protection sub-device and used for regulating and controlling the polar line breakers when a direct-current line fails or the direct-current bus protection sub-device fails.

Preferably, in the above dc field device control system, the dc line protection sub-device is specifically configured to regulate and control the pole line breaker through a built-in high-frequency communication link.

Preferably, in the dc field equipment control system, the dc line protection sub-device is connected to an polar line breaker control device, and when a dc line fails, the polar line breaker control device trips each polar line breaker belonging to the dc line according to a trip signal sent by the dc line protection sub-device, and when it is determined that the dc line is normal, the polar line breaker control device closes each polar line breaker according to a close signal sent by the dc station control device.

Preferably, in the above dc field device control system, the dc field device control system further includes:

a line merging device;

one end of the line merging device is connected with the direct-current station control device, and the other end of the line merging device is connected with the direct-current protection device, and the line merging device is used for acquiring electrical quantities on the direct-current bus and the direct-current line and sending the electrical quantities to the direct-current station control device and the direct-current protection device, wherein the electrical quantities comprise voltage information and current information;

correspondingly, the direct-current station control device receives the electrical quantity, calculates load power on the direct-current bus and the direct-current line according to the electrical quantity, and regulates and controls the position state of the primary equipment based on the load power;

correspondingly, the direct current protection device receives the electrical quantity and regulates and controls each polar line breaker on the direct current bus according to the electrical quantity.

The second aspect of the embodiment of the present invention discloses a method for controlling dc field equipment, which is applied to a dc field equipment control system, wherein the dc field equipment control system includes a workstation, a dc station control device, primary equipment and a dc protection device, and the method includes:

the direct current station control device acquires the position state of the primary equipment and the running state of the direct current protection device and sends a control instruction to the primary equipment;

the workstation monitors the position state of the primary equipment and the running state of the direct current protection device;

the primary equipment regulates and controls the position state according to the control instruction;

and under the condition that a circuit fails, the direct current protection device regulates and controls each polar line breaker on the direct current bus.

Based on the above-mentioned system and method for controlling dc field devices provided by the embodiments of the present invention, the position state of the primary device and the operating state of the dc protection device are obtained by the dc station control device, and a control instruction is sent to the primary device. And the workstation monitors the position state of the primary equipment and the running state of the direct current protection device. And the primary equipment regulates and controls the position state according to the control instruction, and the direct-current protection device regulates and controls each polar line breaker on the direct-current bus under the condition that the line has a fault. Based on the embodiment of the invention, the operation condition of the direct current field equipment can be monitored in real time through the workstation, so that the occurrence position of the fault can be known in real time, the operation of the direct current field equipment can be rapidly regulated and controlled based on the direct current station control device and the direct current protection device, the fault can be timely solved or stopped in advance, the damage of the direct current field equipment is avoided, and the working efficiency and the economic benefit of the converter station are greatly improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a dc field device control system according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of another dc field device control system according to an embodiment of the present invention;

fig. 2a is a schematic connection diagram of a knife switch and an I/O interface module according to an embodiment of the present invention;

FIG. 2b is a schematic diagram of another embodiment of a connection between a knife switch and an I/O interface module;

fig. 2c is a schematic diagram of a connection between an energy consumption device and an ac energy consumption apparatus according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of another dc field device control system according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of another dc field device control system according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of another dc field device control system according to an embodiment of the present invention;

fig. 6 is a schematic diagram illustrating a connection between a circuit merging device and a dc voltage current collecting device according to an embodiment of the present invention;

fig. 7 is a schematic structural diagram of another dc field device control system according to an embodiment of the present invention;

fig. 8 is a schematic flowchart of a method for controlling a dc field device according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In this application, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

As shown in fig. 1, a schematic structural diagram of a dc field device control system provided in an embodiment of the present invention is shown, where the system includes:

the system comprises a direct current station control device 100, a work station 200, primary equipment 300 and a direct current protection device 400.

The dc station control apparatus 100 is configured to obtain a position state of the primary device 300 and an operation state of the dc protection apparatus 400, and send a control instruction to the primary device 300.

It should be noted that the primary device 300 includes, but is not limited to, electrical devices such as line switches, disconnecting links, and energy consuming devices. Accordingly, the position status of the primary appliance 300 includes, but is not limited to, the position of the line switch and/or the knife switch.

The workstation 200 is connected to the dc station control apparatus 100, and is configured to monitor a position state of the primary equipment 300 and an operation state of the dc protection apparatus 400.

Preferably, the workstation 200 is connected to the dc station control device 100 through a first switch, and the workstation 200 is configured to receive, in real time, the position state of the primary device 300 and the operation state of the dc protection device 400 uploaded by the dc station control device 100 through the first switch, and monitor the position state of the primary device 300 and the operation state of the dc protection device 400.

It should be noted that the workstation 200 has a human-computer interaction interface, and based on the human-computer interaction interface, the position state of the primary equipment 300 and the operation state of the dc protection device 400 can be completely displayed and monitored, so as to effectively learn the operation status of each dc field equipment in the dc system of the converter station in real time. The man-machine interface may be a multimedia display device, a computer screen display device, or other devices, and the embodiments of the present invention are not limited thereto.

The primary device 300 is connected to the dc station control apparatus 100, and is configured to regulate and control a position state according to the control instruction.

It should be noted that there is a close relationship between the operating condition of the dc field device and the position state of the primary device 300. The dc station control apparatus 100 sends a control command to the primary device 300 to control the position state of the primary device 300, thereby further controlling the operation status of the dc plant.

The dc protection device 400 is connected to the dc station control device 100, and is configured to regulate and control each pole line breaker on the dc bus when a line fails.

Preferably, the dc protection device 400 is connected to the dc station control device 100 through a third switch, and the dc protection device 400 is configured to send the switching state of each polar line breaker on the line to the dc station control device 100 through the third switch.

It should be noted that, when a line fails, the dc protection device 400 can trip a corresponding pole line breaker, so as to prevent the dc field device from being damaged due to the line failure. Furthermore, in order to prevent some unpredictable accidents in the converter station, a technician may configure a plurality of sets of said dc station control devices 100 and dc protection devices 400 according to actual conditions to prevent backup.

It should be noted that the first switch and the second switch are switches of any form, and the embodiment of the present invention is not limited thereto.

In the embodiment of the invention, the position state of the primary equipment and the running state of the direct current protection device are obtained through the direct current station control device, and a control instruction is sent to the primary equipment. And the workstation monitors the position state of the primary equipment and the running state of the direct current protection device. And the primary equipment regulates and controls the position state according to the control instruction, and the direct-current protection device regulates and controls each polar line breaker on the direct-current bus under the condition that the line has a fault. Based on the embodiment of the invention, the operation condition of the direct current field equipment can be monitored in real time through the workstation, so that the occurrence position of the fault can be known in real time, the operation of the direct current field equipment can be rapidly regulated and controlled based on the direct current station control device and the direct current protection device, the fault can be timely solved or stopped in advance, the damage of the direct current field equipment is avoided, and the working efficiency and the economic benefit of the converter station are greatly improved.

Preferably, referring to fig. 2 in combination with fig. 1, a schematic structural diagram of another dc field device control system according to an embodiment of the present invention is provided. In fig. 2, the dc station control apparatus 100 is connected to the primary device 300 through an interface device 310, and the dc station control apparatus 100 is configured to obtain a position state of the primary device 300 in real time based on the interface device 310 and send a control instruction to the corresponding primary device 300.

Wherein the interface device 310 comprises: a DC field station control interface device 311, a bipolar area DC field interface device 312 and an AC energy consumption device 313.

The dc field station control interface device 311 is connected to the dc station control device 100 through a second switch, and the dc field station control interface device 311 is configured to acquire a position state of the primary device 300, send the position state to the dc station control device 100, and forward a control instruction sent by the dc station control device 100 to the corresponding primary device 300.

It should be noted that the dc field station control interface device 311 acquires the position states of the switch and the disconnecting link on the dc line through the I/O interface module. The positive direct-current line and the negative direct-current line respectively correspond to an I/O interface module, and the I/O interface module is powered by an independent power supply. In the embodiment of the present invention, the I/O interface module may be external or internal to the dc field station control interface device 311.

The dc station control apparatus 100 may perform interlock control on the corresponding primary device 300 based on the dc station control interface apparatus 311.

For convenience of understanding a specific interlocking relationship of each primary device in the interlocking control process, it is assumed that the primary device is a specific connection relationship between a switch, a switch and an I/O interface module, and fig. 2a is a schematic connection diagram of a switch and an I/O interface module according to an embodiment of the present invention. The interlocking relationship between the respective switches is explained based on the condition that the respective switches switch the opening and closing positions in fig. 2 a. In fig. 2a, the conditions for switching the switching positions of the knife switches include:

the on-position condition of the knife switch Q26 is as follows: knife switch Q11 and knife switch Q14 are in the disengaged position at the same time. The open condition of the knife switch Q26 is not limited, in other words, the knife switch Q26 is always in the open position in any time when the close condition of the knife switch Q26 is not met. Therefore, the knife switch Q26 is always in the open state, and when the knife switch Q11 and the knife switch Q14 are opened simultaneously, the knife switch Q26 is closed.

The on-position condition of the knife switch Q11 is as follows: knife switch Q1, knife switch Q14, knife switch Q21 and knife switch Q22 are in the open position at the same time. The position separating condition of the knife switch Q11 is as follows: knife switch Q1 or knife switch Q14 is in the open position and the current on the dc link is less than 1000A. Therefore, when the knife switch Q1, the knife switch Q14, the knife switch Q21 and the knife switch Q22 are switched off simultaneously, the knife switch Q11 is switched on; when the knife switch Q1 or the knife switch Q14 is opened and the current on the direct current line is less than 1000A, the knife switch Q11 is opened.

The on-position condition of the knife switch Q12 is as follows: the knife switch Q1, the knife switch Q21, the knife switch Q22 and the knife switch Q23 are in the open position at the same time, the knife switch Q24 is in the open position or the knife switch Q14 is in the closed position, and in addition, the current on the direct current line is less than 1200A. The position separating condition of the knife switch Q12 is as follows: knife switch Q1 is in the open position. Therefore, when the knife switch Q1, the knife switch Q21, the knife switch Q22 and the knife switch Q23 are switched off at the same time, the knife switch Q24 is switched off or the knife switch Q14 is switched on, and the current on the direct current line is less than 1200A, the knife switch Q12 is switched on; when the knife switch Q1 is opened, the knife switch Q12 is opened.

The on-position condition of the knife switch Q14 is as follows: knife switch Q21, knife switch Q23, and knife switch Q24 are in the open position at the same time and the current on the dc link is less than 1500A. The position separating condition of the knife switch Q14 is as follows: knife switch Q13 is in a split or line-to-line dc line isolation and the voltage on the dc bus is less than 100V and the voltage on the dc line is less than 120V and, in addition, the current on the dc line is less than 1100A. Therefore, when the knife switch Q21, the knife switch Q23 and the knife switch Q24 are switched off simultaneously and the current on the direct current line is less than 1500A, the knife switch Q14 is switched on; when the knife switch Q13 is opened or the dc line on the opposite side of the line is isolated, and the voltage on the dc bus is less than 100V, and the voltage on the dc line is less than 120V, the current on the dc line is less than 1100A, the knife switch Q14 opens.

Wherein, the direct current line on the opposite side of the line refers to: and (c) a corresponding direct current line in the second converter station, which is in power transmission connection with the first converter station to which the line of fig. 2a belongs.

The on-position condition of the knife switch Q1 is as follows: the knife switch Q1 is unlocked and allows the knife switch Q1 to be in the closed position, and in addition, the knife switch Q11 and the knife switch Q12 are in the open position or in the closed position at the same time. The position separating condition of the knife switch Q1 is as follows: allowing the knife switch Q1 to open. Therefore, when the knife switch Q1 can be switched on and the knife switch Q11 and the knife switch Q12 can be switched on and off simultaneously, the knife switch Q1 is switched on; when the switch Q1 can be opened, the switch Q1 is opened.

The on-position condition of the knife switch Q21 is as follows: knife switch Q11 is in the open position and knife switch Q12 is in the open position. The open condition of the knife switch Q21 is not limited, in other words, the knife switch Q21 is always in the open position in any time when the close condition of the knife switch Q21 is not met. Therefore, the knife switch Q21 is always in the open state, and when the knife switch Q11 and the knife switch Q12 are opened simultaneously, the knife switch Q21 is closed.

The on-position condition of the knife switch Q22 is as follows: knife switch Q11 is in the open position and knife switch Q12 is in the open position. The open condition of the knife switch Q22 is not limited, in other words, the knife switch Q22 is always in the open position in any time when the close condition of the knife switch Q22 is not met. Therefore, the knife switch Q22 is always in the open state, and when the knife switch Q11 and the knife switch Q12 are opened simultaneously, the knife switch Q22 is closed.

The on-position condition of the knife switch Q23 is as follows: knife switch Q12, knife switch Q13 and knife switch Q14 are in the open position at the same time. The open condition of the knife switch Q23 is not limited, in other words, the knife switch Q23 is always in the open position in any time when the close condition of the knife switch Q23 is not met. Therefore, the knife switch Q23 is always in the open state, and when the knife switch Q12, the knife switch Q13 and the knife switch Q14 are opened simultaneously, the knife switch Q23 is closed.

The on-position condition of the knife switch Q24 is as follows: knife switch Q12, knife switch Q13 and knife switch Q14 are in the open position at the same time. The open condition of the knife switch Q24 is not limited, in other words, the knife switch Q24 is always in the open position in any time when the close condition of the knife switch Q24 is not met. Therefore, the knife switch Q24 is always in the open state, and when the knife switch Q12, the knife switch Q13 and the knife switch Q14 are opened simultaneously, the knife switch Q24 is closed.

The on-position condition of the knife switch Q25 is as follows: knife switch Q13 is in the disengaged position and the voltage on the dc link is less than 150V, and in addition, knife switch Q13 on the opposite side of the link is in the disengaged position. Therefore, the knife switch Q25 is always in the open state, and when the knife switch Q13 and the knife switch Q13 on the opposite side of the line are opened simultaneously and the voltage on the direct current line is less than 150V, the knife switch Q25 is closed.

Wherein the line-opposite knife switch Q13 refers to: a knife switch Q13 on the corresponding dc link in the second converter station, which is in power transmission connection with the first converter station to which the link of fig. 2a belongs.

The on-position condition of the knife switch Q13 is as follows: the knife switch Q14 is in the open position, and the knife switch Q23, the knife switch Q24 and the knife switch Q25 are simultaneously in the open position, and in addition, at least one of the knife switch Q1, the knife switch Q11 and the knife switch Q12 is in the open position. The position separating condition of the knife switch Q13 is as follows: the switch Q14 is in the open position and at least one of the switches Q1, Q11 and Q12 is in the open position. Therefore, when the knife switch Q14, the knife switch Q23, the knife switch Q24 and the knife switch Q25 are switched off simultaneously, and at least one knife switch of the knife switch Q1, the knife switch Q11 and the knife switch Q12 is switched off, the knife switch Q13 is switched on; when the knife switch Q14 is opened and at least one knife switch of the knife switch Q1, the knife switch Q11 and the knife switch Q12 is opened, the knife switch Q13 is opened.

It should be noted that the above mentioned contents are only used for illustration, for example, the specific value of the "voltage on the dc line is less than 150V" can be set by a skilled person according to the actual situation, and furthermore, the specific on condition and off condition of each knife switch can be set by the skilled person according to the actual situation, and the embodiment of the present invention is not limited.

The bipolar area dc field interface device 312 is connected to the dc station control device 100 through the second switch, and the bipolar area dc field interface device 312 is configured to acquire a position state of the primary device 300, send the position state to the dc station control device 100, and forward a control instruction sent by the dc station control device 100 to the corresponding primary device 300.

It should be noted that the bipolar area dc field interface device 312 collects the position states of the switch and the knife switch on the metal return line through two I/O interface modules. Wherein the I/O interface module is powered by an independent power supply. In the embodiment of the present invention, the I/O interface module may be external or internal to the bipolar area dc field interface device 312.

It should be noted that, based on the bipolar area dc field interface device 312, the dc station control device 100 can perform interlock control on the corresponding primary device 300.

For convenience of understanding a specific interlocking relationship of each primary device in the interlocking control process, it is assumed that the primary device is a specific connection relationship between a knife switch, a knife switch and an I/O interface module, and refer to fig. 2b, which is a schematic connection diagram of another knife switch and an I/O interface module according to an embodiment of the present invention. The interlocking relationship between the switches is explained based on the condition that the switches switch on/off positions in fig. 2 b. In fig. 2b, the conditions for switching the switching positions of the knife switches include:

the on-position condition of the knife switch Q13 is as follows: neutral Bus Switch (NBS) and knife Switch Q24 are in the open position at the same time. The position separating condition of the knife switch Q13 is as follows: NBS is in quantile. Therefore, when NBS and the knife switch Q24 are switched off simultaneously, the knife switch Q13 is switched on; when only NBS is opened, the knife switch Q13 is opened.

The on-position condition of the knife switch Q24 is as follows: knife switch Q11 and knife switch Q13 are in the disengaged position at the same time. The open condition of the knife switch Q24 is not limited, in other words, the knife switch Q24 is always in the open position in any time when the close condition of the knife switch Q24 is not met. Therefore, the knife switch Q24 is always in the open state, and when the knife switch Q11 and the knife switch Q13 are opened simultaneously, the knife switch Q24 is closed.

The on-position condition of the knife switch Q11 is as follows: knife switch Q1, knife switch Q24, knife switch Q21 and knife switch Q22 are in the open position at the same time. The position separating condition of the knife switch Q11 is as follows: knife switch Q1 is in the open position. Therefore, when the knife switch Q1, the knife switch Q24, the knife switch Q21 and the knife switch Q22 are switched off simultaneously, the knife switch Q11 is switched on; when the knife switch Q1 is opened, the knife switch Q11 is opened.

The on-position condition of the knife switch Q12 is as follows: knife switch Q1, knife switch Q21, knife switch Q22 and knife switch Q23 are in the open position at the same time. The position separating condition of the knife switch Q12 is as follows: knife switch Q1 is in the open position. Therefore, when the knife switch Q1, the knife switch Q21, the knife switch Q22 and the knife switch Q23 are switched off simultaneously, the switch Q12 is switched on; when the knife switch Q1 is opened, the knife switch Q12 is opened.

The on-position condition of the knife switch Q21 is as follows: knife switch Q11 and knife switch Q12 are in the disengaged position at the same time. The open condition of the knife switch Q21 is not limited, in other words, the knife switch Q21 is always in the open position in any time when the close condition of the knife switch Q21 is not met. Therefore, the knife switch Q21 is always in the open state, and when the knife switch Q11 and the knife switch Q12 are opened simultaneously, the knife switch Q21 is closed.

The on-position condition of the knife switch Q22 is as follows: knife switch Q11 and knife switch Q12 are in the disengaged position at the same time. The open condition of the knife switch Q22 is not limited, in other words, the knife switch Q22 is always in the open position in any time when the close condition of the knife switch Q22 is not met. Therefore, the knife switch Q22 is always in the open state, and when the knife switch Q11 and the knife switch Q12 are opened simultaneously, the knife switch Q22 is closed.

The on-position condition of the knife switch Q23 is as follows: knife switch Q12 and line-opposite knife switch Q12 are both in the disengaged position. The open condition of the knife switch Q23 is not limited, in other words, the knife switch Q23 is always in the open position at any time when the close condition of the knife switch Q23 is not satisfied. Therefore, the knife switch Q23 is always in the open state, and when the knife switch Q12 and the knife switch Q12 on the opposite side of the line are opened simultaneously, the knife switch Q23 is closed.

Wherein the line-opposite knife switch Q12 refers to: a knife switch Q12 on the corresponding dc link in the second converter station, which is in power transmission connection with the first converter station to which the link of fig. 2b belongs.

The on-position condition of the knife switch Q1 is as follows: the knife switch Q11 and the knife switch Q12 are in the open position or the closed position at the same time. The position separating condition of the knife switch Q1 is as follows: the knife switch Q1 is unlocked and the current on the metallic return is less than 1100A. Therefore, when the knife switch Q11 and the knife switch Q12 are switched off or switched on simultaneously, the knife switch Q1 is switched on; when the switch Q1 is unlocked and the current on the metallic return line is less than 1100A, the switch Q1 is opened.

It should be noted that the above mentioned contents are only used for illustration, for example, the specific value of the current on the metallic return wire being less than 1100A may be set by a skilled person according to the actual situation, and furthermore, the specific on-position condition and off-position condition of each knife switch may be set by the skilled person according to the actual situation, and the embodiment of the present invention is not limited.

The ac energy consuming device 313 is connected to the dc station control device 100 through the second switch, and the ac energy consuming device 313 is configured to connect the energy consuming equipment in the primary equipment 300 to the dc bus when the load power of the dc line is greater than a first threshold, and disconnect the energy consuming equipment from the dc bus when the surplus power consumed by the energy consuming equipment causes the load power of the dc line to be less than a second threshold, where the second threshold is less than the first threshold.

It should be noted that, based on the dc voltage and current collecting device in the converter station, the dc station control device 100 may obtain voltage information and current information on the dc bus and the dc line, and calculate the load power based on the voltage information and the current information. In addition, the specific values of the first threshold and the second threshold can be set by a technician according to actual situations.

It should be noted that, when any line of the flexible dc power grid cannot normally operate due to a fault, the flexible dc power grid may be overloaded and damage the dc field device. In the embodiment of the invention, the energy consumption equipment is connected into the direct current bus, so that the energy consumption equipment consumes surplus power, and the overload phenomenon of the flexible direct current power grid is prevented.

To facilitate understanding of a specific process of the dc station control apparatus 100 connecting the energy consuming device to the dc bus through the ac energy consuming device 313, refer to fig. 2c, which is a schematic diagram illustrating a connection between the energy consuming device and the ac energy consuming device according to an embodiment of the present invention. Based on the specific connection relationship between the energy consuming devices and the ac energy consuming apparatus shown in fig. 2c, the following explains the process of the ac energy consuming apparatus connecting the energy consuming devices to the dc bus through steps a1-a 5:

a1, the direct current station control device obtains voltage information and current information on the direct current bus and the direct current line, and calculates the load power of the direct current line based on the voltage information and the current information.

A2, the DC station control device judges whether the current load power of the DC line is more than 1000KW, if the current load power is more than 1000KW, A3 is executed, otherwise, A1 is executed.

A3, the direct current station control device sends a working instruction to an alternating current energy consumption device, the alternating current energy consumption device forwards a turn-on signal to energy consumption equipment according to the working instruction, and a thyristor VT inside the energy consumption equipment is turned on, so that the energy consumption equipment is connected into a direct current bus. And the energy consumption equipment is connected with the direct current bus, surplus power in the direct current system is consumed, and A4 is executed.

A4, the direct current station control device judges whether the current load power of the direct current line is smaller than 800KW, if the current load power is smaller than 800KW, A5 is executed, otherwise, the connection relation between the energy consumption equipment and the direct current bus is kept.

A5, the direct current station control device sends a turn-off instruction to the alternating current energy consumption device, the alternating current energy consumption device forwards a turn-off signal to the energy consumption equipment according to the turn-off instruction, a thyristor in the energy consumption equipment is turned off, the connection relation between the energy consumption equipment and the direct current bus is disconnected, and the energy consumption equipment stops running.

It should be noted that the specific values involved in the steps a1-a5 are only used for illustration, for example, the specific values involved in "the dc station control apparatus determines whether the current load power of the dc line is greater than 1000 KW" may be set by a skilled person according to practical situations, and the embodiment of the present invention is not limited thereto.

It should be noted that the second switch may be any type of switch, and the embodiment of the present invention is not limited thereto.

In the embodiment of the invention, the direct current station control device is connected with the primary equipment through the interface device, and the interlocking control of the corresponding primary equipment is realized through the interface device. Wherein the interface device comprises: the system comprises a direct current field station control interface device, a bipolar area direct current field interface device and an alternating current energy consumption device. Based on the invention, the direct current station control device acquires and controls the position state of the primary equipment through the interface device, and can effectively avoid the damage of the direct current field equipment caused by the line fault.

Preferably, referring to fig. 3 in combination with fig. 1, for a structural schematic diagram of another dc field device control system provided in an embodiment of the present invention, the dc protection device 400 includes:

a dc bus protection sub-assembly 410 and a dc line protection sub-assembly 420.

The dc bus protection sub-device 410 is connected to the dc station control device 100 through a third switch, and is configured to send the switching state of each polar line breaker on the dc bus to the dc station control device 100, and regulate and control each polar line breaker when a line fault occurs or the polar line breaker fails.

It should be noted that, when a line fault occurs, the dc bus protection sub-device 410 trips each polar line breaker on the dc bus of the first converter station, and sends a failure signal to the dc bus protection sub-device 410 of the second converter station when it is determined that any polar line breaker fails and is not tripped, and the dc bus protection sub-device 410 of the second converter station trips each polar line breaker on the dc bus of the second converter station according to the failure signal. The first converter station is in power transmission connection with the second converter station through a direct current line.

It should be noted that, when a line fails, the dc bus protection sub-device 410 trips each pole line breaker on the dc bus, so that the dc field device in the failed line stops working, and the dc field device is prevented from being damaged due to the line failure.

The dc line protection sub-device 420 is connected to the dc bus protection sub-device 410, and is configured to regulate and control each of the pole line breakers when a dc line fails or the dc bus protection sub-device 410 fails.

Wherein the dc line protection sub-device 420 is connected to the dc bus protection sub-device 410 through an optical fiber.

It should be noted that, when a dc line fails, the dc line protection sub-device 420 trips pole line breakers in the first converter station and the second converter station, and trips pole line breakers directly connected to the failed pole line breaker when the dc bus protection sub-device 410 and any one of the pole line breakers fail simultaneously.

In the embodiment of the invention, when a line fault or an electrode line breaker has a fault, the corresponding electrode line breaker is quickly and accurately tripped based on the direct-current bus protection sub-device and the direct-current line protection sub-device, so that the damage of direct-current field equipment caused by untimely fault treatment can be effectively avoided.

Preferably, referring to fig. 4 in combination with fig. 3, a schematic structural diagram of another dc field device control system provided in the embodiment of the present invention is shown.

In fig. 4, the dc line protection sub-device 420 is specifically configured to regulate and control a pole line breaker through a built-in high-frequency communication link 421.

It should be noted that, based on the high-frequency communication link 421, the dc line protection sub-device 420 can enable the pole line breaker to complete tripping quickly.

The dc line protection sub-device 420 is connected with the pole line breaker control device 422, and when a dc line fault occurs, the pole line breaker control device 422 trips each pole line breaker belonging to the dc line according to a tripping signal sent by the dc line protection sub-device 420, and determines that the dc line is normal, the pole line breaker control device 422 closes each pole line breaker according to a closing signal sent by the dc station control device 100.

In the embodiment of the invention, the direct-current line protection sub-device rapidly trips the polar circuit breaker through a built-in high-frequency communication link. When a line fault occurs, the pole line breaker control device trips each pole line breaker belonging to the direct-current line according to a tripping signal sent by the direct-current line protection sub-device, and determines that the direct-current line is normal, the pole line breaker control device switches on each pole line breaker according to a switching-on signal sent by the direct-current station control device. Based on the embodiment of the invention, when a line fault occurs, the corresponding polar circuit breaker can be tripped in time, the damage of direct-current field equipment caused by the line fault is avoided, and after the line is recovered to be normal, the corresponding polar circuit breaker is switched on, the normal work of the converter station is recovered, and the working efficiency and the economic benefit of the converter station are effectively improved.

Preferably, referring to fig. 5 in combination with fig. 1, a schematic structural diagram of another dc field device control system provided in an embodiment of the present invention is further provided, where the system further includes:

a line merging device 500, where one end of the line merging device 500 is connected to the dc station control device 100, and the other end of the line merging device 500 is connected to the dc protection device 400, and is configured to obtain electrical quantities on the dc bus and the dc line, and send the electrical quantities to the dc station control device 100 and the dc protection device 400, where the electrical quantities include voltage information and current information.

It should be noted that the line merging apparatus 500 is connected to the dc station control apparatus 100 and the dc protection apparatus 400 through optical fibers, respectively. The line merging device 500 obtains the electrical quantity sent by each primary transformer in the line through the dc voltage and current collecting device, processes the electrical quantity accordingly, and sends the electrical quantity obtained after processing to the dc station control device 100 and the dc protection device 400 in a digital signal manner.

To facilitate understanding of the specific implementation process of the line merging device 500 for acquiring the electrical quantity, referring to fig. 6, a schematic connection diagram between the line merging device and the dc voltage current collecting device according to an embodiment of the present invention is provided. In fig. 6, the dc voltage current collecting device includes a dc voltage divider and a photocurrent transformer, and the dc voltage current collecting device is respectively connected to the line shown in fig. 2a and the line shown in fig. 2b, and collects voltage information and current information on the lines in real time through the dc voltage divider and the photocurrent transformer installed on the lines. Referring to fig. 6, the process of obtaining the electrical quantity by the line merging device is explained by B1-B3:

and B1, the direct current voltage divider collects voltage information on a direct current bus and a direct current line and sends the voltage information to a line merging device. The direct voltage divider includes: voltage divider UDMB, voltage divider UDLB and voltage divider UDL 1.

And B2, the photocurrent transformer collects current information on the direct current bus and the direct current line and sends the current information to the line merging device. The photocurrent transformer includes: a transformer IDM1, a transformer IDML11, a transformer IDML12, a transformer IDGND, a transformer IDB1 and a transformer IDL 1.

And B3, the line merging device receives the voltage information and the current information, merges and synchronizes the voltage information on the direct current bus and the direct current line, and merges and synchronizes the current information on the direct current bus and the direct current line.

It should be noted that, the "merging and synchronizing" mentioned in the step B3 specifically refers to: merging the voltage information on the direct current bus and the direct current line, synchronizing the acquisition time of the voltage information, and comprehensively obtaining real-time voltage information on the whole line; and combining the current information on the direct current bus and the direct current line, synchronizing the acquisition time of each voltage information, and comprehensively obtaining the real-time current information on the whole line.

Correspondingly, the dc station control device 100 receives the electrical quantity, calculates the load power on the dc bus and the dc line according to the electrical quantity, and regulates the position state of the primary device 300 based on the load power.

The load power can be obtained based on a product between the voltage and the current in the electrical quantity.

Correspondingly, the dc protection device 400 receives the electrical quantity, and regulates and controls each pole line breaker on the dc bus according to the electrical quantity.

In the embodiment of the invention, the line merging device sends the electrical quantities on the direct current bus and the direct current line to the direct current station control device and the direct current protection device. And the direct current station control device obtains the load power on the line according to the electrical quantity, and regulates and controls the position state of the primary equipment based on the load power. And the direct current protection device regulates and controls each polar line breaker based on the electrical quantity. Based on the invention, the occurrence of the fault can be pre-judged in real time according to the voltage and current information on the line, and the connection between the fault position and the direct current field equipment is shut off in advance, so that the direct current field equipment is prevented from being damaged.

For the convenience of understanding the dc field device control system shown in fig. 1 to 6, the following description will be made in detail with reference to specific examples. As shown in fig. 7, a schematic structural diagram of another dc field device control system provided in an embodiment of the present invention is shown, where the system includes:

the workstation 701 is connected to the dc station control device 704 through the first switch 702, and the workstation 701 receives the position state of the primary device 713, the operation states of the dc bus protection sub-device 711 and the dc line protection sub-device 712 uploaded by the dc station control device 704 through the first switch 702 in real time, and monitors the position state of the primary device 713 and the operation states of the dc bus protection sub-device 711 and the dc line protection sub-device 712.

The dc station control device 704 is connected to the primary device 713 through an interface device, and the dc station control device 704 obtains the position state of the primary device 713 in real time based on the interface device and sends a control instruction to the corresponding primary device 713. Wherein the interface device comprises: a dc field station control interface device 708, a bipolar area dc field interface device 709, and an ac energy consuming device 710.

The dc field station control interface device 708 is connected to the dc station control device 704 through the second switch 706, and the dc field station control interface device 708 acquires the position state of the primary device 713, sends the position state to the dc station control device 704, and forwards the control instruction sent by the dc station control device 704 to the corresponding primary device 713.

The bipolar area dc field interface device 709 is connected to the dc station control device 704 through the second switch 706, and the bipolar area dc field interface device 709 collects the position state of the primary device 713, sends the position state to the dc station control device 704, and forwards the control instruction sent by the dc station control device 704 to the corresponding primary device 713.

The ac energy consuming apparatus 710 is connected to the dc station control apparatus 704 through the second switch 706, and when the load power of the dc line is greater than 500KW, the ac energy consuming apparatus 710 connects the energy consuming device in the primary device 713 to the dc bus, and when the surplus power consumed by the energy consuming device causes the load power of the dc line to be less than 400KW, the connection between the energy consuming device and the dc bus is disconnected.

The primary device 713 regulates the position state according to the control instruction.

The dc bus protection sub-device 711 is connected to the dc station control device 704 through a third switch 707, and the dc bus protection sub-device 711 sends the switching state of each polar line breaker on the dc bus to the dc station control device 704, and regulates and controls each polar line breaker when a line fault or the polar line breaker fault occurs.

The dc line protection sub-device 712 is connected to the dc bus protection sub-device 711, and when a dc line fails or the dc bus protection sub-device 711 fails, the dc line protection sub-device 712 controls each of the pole line breakers.

The dc line protection sub-device 712 is connected to the pole line breaker control device 703, when a dc line fails, the pole line breaker control device 703 trips each pole line breaker belonging to the dc line according to a trip signal sent by the dc line protection sub-device 712, and when it is determined that the dc line is normal, the pole line breaker control device 703 switches on each pole line breaker according to a switch-on signal sent by the dc station control device 704.

One end of the line merging device 705 is connected to the dc station control device 704, and the other end is connected to the dc bus protection sub-device 711, where the line merging device 705 obtains electrical quantities on the dc bus and the dc line, and sends the electrical quantities to the dc station control device 704 and the dc bus protection sub-device 711. The dc station control device 704 receives the electrical quantity, calculates load power on the dc bus and the dc line according to the electrical quantity, and regulates the position state of the primary device 713 based on the load power.

Based on the direct current field device control system provided by the embodiment of the invention, the embodiment of the invention also correspondingly provides a direct current field device control method. As shown in fig. 8, which is a schematic flow chart of a method for controlling a dc field device according to an embodiment of the present invention, the method is applied to a dc field device control system, the dc field device control system includes a dc station control device, a workstation, a primary device, and a dc protection device, and the method includes:

s101: the direct current station control device acquires the position state of the primary equipment and the running state of the direct current protection device, and sends a control instruction to the primary equipment.

In S101, the dc station control device is connected to the primary device through an interface device, and the dc station control device obtains a position state of the primary device in real time based on the interface device, and sends a control instruction to the corresponding primary device.

It should be noted that the dc station control device may further receive an electrical quantity sent by a line merging device, calculate load powers on the dc bus and the dc line according to the electrical quantity, and regulate the position state of the primary device based on the load powers. Wherein the electrical quantity comprises voltage information and current information on the direct current bus and the direct current line.

S102: the workstation monitors the position state of the primary equipment and the running state of the direct current protection device.

In S102, the workstation is connected to the dc station control device through a first switch, and the workstation receives the position state of the primary device and the operating state of the dc protection device, which are uploaded by the dc station control device, in real time through the first switch, and monitors the position state of the primary device and the operating state of the dc protection device.

S103: and the primary equipment regulates and controls the position state according to the control instruction.

In S103, since the primary devices are connected to the dc station control apparatus through different interface devices, and the interface devices are different from each other, processes of receiving the control command by the primary devices may be different.

Preferably, the dc field station control interface device is connected to the dc station control device through a second switch, and the dc field station control interface device collects the position state of the primary device, sends the position state to the dc station control device, and forwards a control instruction sent by the dc station control device to the corresponding primary device.

Preferably, the bipolar area dc field interface device is connected to the dc station control device through the second switch, and the bipolar area dc field interface device collects the position state of the primary device, sends the position state to the dc station control device, and forwards the control instruction sent by the dc station control device to the corresponding primary device.

Preferably, the ac energy consuming device is connected to the dc station control device through the second switch, and when the load power of the dc line is greater than a first threshold, the ac energy consuming device connects the energy consuming equipment in the primary equipment to the dc bus, and when the surplus power consumed by the energy consuming equipment causes the load power of the dc line to be less than a second threshold, the connection between the energy consuming equipment and the dc bus is disconnected, and the second threshold is less than the first threshold.

S104: under the condition that a line has a fault, the direct-current protection device regulates and controls each polar line breaker on the direct-current bus.

In S104, the dc protection device is connected to the dc station control device through a third switch, and the dc protection device transmits the switching state of each polar line breaker on the line to the dc station control device through the third switch.

Preferably, the dc station control device includes a dc bus protection sub-device and a dc line protection sub-device.

The direct-current bus protection sub-device is connected with the direct-current station control device through a third switch, and is used for sending the switching-on/off state of each polar line breaker on the direct-current bus to the direct-current station control device and regulating and controlling each polar line breaker when a line fault or the polar line breaker is in fault.

It should be noted that the dc line protection sub-apparatus is specifically configured to regulate and control an electrode line breaker through a built-in high-frequency communication link.

Preferably, the dc line protection sub-device is connected to an electrode line breaker control device, when a dc line fails, the electrode line breaker control device trips each electrode line breaker belonging to the dc line according to a trip signal sent by the dc line protection sub-device, and when it is determined that the dc line is normal, the electrode line breaker control device closes each electrode line breaker according to a close signal sent by the dc station control device.

It should be noted that, the dc protection device also receives the electrical quantity sent by the line merging device, and regulates and controls each pole line breaker on the dc bus according to the electrical quantity.

It should be noted that, the specific execution sequence of steps S101 to S104 includes but is not limited to the above execution sequence, and steps S101 to S104 may also be executed synchronously, which is not limited in the embodiment of the present invention.

In summary, in the system and method for controlling a dc farm device according to the embodiments of the present invention, a dc station control device obtains a position state of a primary device and an operating state of a dc protection device, and sends a control instruction to the primary device. And the workstation monitors the position state of the primary equipment and the running state of the direct current protection device. And the primary equipment regulates and controls the position state according to the control instruction, and the direct-current protection device regulates and controls each polar line breaker on the direct-current bus under the condition that the line has a fault. Based on the embodiment of the invention, the operation condition of the direct current field equipment can be monitored in real time through the workstation, so that the occurrence position of the fault can be known in real time, the operation of the direct current field equipment can be rapidly regulated and controlled based on the direct current station control device and the direct current protection device, the fault can be timely solved or stopped in advance, the damage of the direct current field equipment is avoided, and the working efficiency and the economic benefit of the converter station are greatly improved.

The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, the system or system embodiments are substantially similar to the method embodiments and therefore are described in a relatively simple manner, and reference may be made to some of the descriptions of the method embodiments for related points. The above-described system and system embodiments are only illustrative, wherein the units described as separate parts may or may not be physically separate, and the parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. One of ordinary skill in the art can understand and implement it without inventive effort.

Those of skill would further appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the various illustrative components and steps have been described above generally in terms of their functionality in order to clearly illustrate this interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A dc field device control system, the system comprising:

the direct current station control device is used for acquiring the position state of the primary equipment and the running state of the direct current protection device, and sending a control instruction to the primary equipment so as to control the position state of the primary equipment;

the direct-current protection device is connected with the direct-current station control device and used for regulating and controlling each polar line breaker on the direct-current bus under the condition that a line has a fault;

a line merging device;

2. The system according to claim 1, wherein the workstation is connected to the dc station control device through a first switch, and the workstation is configured to receive, through the first switch, the position state of the primary device and the operating state of the dc protection device uploaded by the dc station control device in real time, and monitor the position state of the primary device and the operating state of the dc protection device.

3. The system according to claim 1, wherein the dc station control device is connected to the primary device through an interface device, and the dc station control device is configured to obtain a position state of the primary device in real time based on the interface device and send a control instruction to the corresponding primary device.

4. The system of claim 3, wherein the interface device comprises:

and/or the presence of a gas in the gas,

5. The system according to claim 1, wherein the dc protection device is connected to the dc station control device through a third switch, and the dc protection device is configured to send the switching state of each of the pole-line breakers on the line to the dc station control device through the third switch.

6. The system of claim 1, wherein the dc protection device comprises:

a DC bus protection sub-device and a DC line protection sub-device;

7. System according to claim 6, characterized in that the direct current line protection sub-arrangement is in particular used for the regulation of pole line breakers through a built-in high frequency communication link.

8. The system according to claim 6, wherein the dc line protection sub-device is connected to an polar circuit breaker control device, and when a dc line fails, the polar circuit breaker control device trips each polar circuit breaker belonging to the dc line according to a trip signal transmitted from the dc line protection sub-device, and when it is determined that the dc line is normal, the polar circuit breaker control device closes each polar circuit breaker according to a close signal transmitted from the dc station control device.

9. A control method of direct current field equipment is characterized by being applied to a control system of the direct current field equipment, wherein the control system of the direct current field equipment comprises a workstation, a direct current station control device, primary equipment, a line merging device and a direct current protection device, and the method comprises the following steps:

the direct current station control device acquires the position state of the primary equipment and the running state of the direct current protection device, and sends a control instruction to the primary equipment so as to control the position state of the primary equipment;

under the condition that a circuit fails, the direct-current protection device regulates and controls each polar line breaker on a direct-current bus;

the line merging device acquires electrical quantities on the direct-current bus and the direct-current line and sends the electrical quantities to the direct-current station control device and the direct-current protection device, wherein the electrical quantities comprise voltage information and current information;