DC line fault detection system and methodTechnical Field
The invention belongs to the technical field of relay protection, and particularly relates to a direct-current line fault detection system and a detection method of the direct-current line fault detection system.
Background
With the expansion of the scale of the interconnected power grid and the continuous rise of the voltage grade, the setting coordination of the traditional backup protection based on local information is complex, the action is long, the requirement of safe operation of the power grid is difficult to meet, when the power flow is transferred and the system oscillates, the traditional backup protection can mistakenly cut off a normal line, and the sensitivity of the traditional backup protection can be influenced by a high-resistance grounding fault.
At present, fault detection of a direct current line is mainly realized through the current or voltage change condition of the direct current line. When the current of the direct current line is continuously increased and is larger than the current threshold value, judging that the direct current line has a fault; or when the voltage of the direct current line is reduced and is smaller than the voltage threshold value, the direct current line is judged to be in fault. When a direct current line has a fault, the current of the direct current line comprises a load component and a fault component, when a slight fault such as grounding through high resistance occurs during the heavy load period of the direct current line, the load component is large, the fault component is small, the load component is larger than the fault component, and the fault characteristic is covered.
Disclosure of Invention
The invention aims to provide a direct current line fault detection system, which solves the problems of inaccurate direct current line fault detection and low sensitivity in the prior art.
The invention also aims to provide the detection method of the direct current line fault detection system, which has the characteristics of convenient operation and accurate detection.
The technical scheme adopted by the invention is that the direct current line fault detection system comprises a current acquisition module, a wireless communication module and a line fault analysis platform; the current acquisition module transmits the detection information of the direct current line to the line fault analysis table through the wireless communication module.
The technical scheme of the invention is also characterized in that:
the current acquisition module is used for collecting data of the direct current line.
The current acquisition module comprises a circular iron core current transformer, the circular iron core current transformer comprises a circular iron core, a secondary coil, an integrating circuit, a support and a porcelain insulator, the secondary coil comprises a measurement winding and a power supply winding, the measurement winding and the power supply winding are wound on the circular iron core, two ends of the measurement winding are connected with the integrating circuit, two ends of the power supply winding are connected with the integrating circuit, the circular iron core and the integrating circuit are both arranged in the support, and the support is arranged in the porcelain insulator; the bottom of the porcelain insulator is provided with a through hole.
The round iron core current transformer is connected with a microprocessor through an integrating circuit.
The microprocessor is model NRF 51822-QFAA-R.
According to the other technical scheme, the detection method of the direct-current line fault detection system comprises the steps that firstly, current fault information of a direct-current line is collected through a current collection module and then is transmitted to a line fault analysis table through a wireless communication module; and the line fault analysis station reads the data of the power transmission direct current line.
The invention has the beneficial effects that:
(1) the direct-current line fault detection system can accurately detect the fault of the direct-current line and is convenient for timely corresponding adjustment; the direct-current line fault detection system improves the detection efficiency, shortens the detection time and can effectively prevent and reduce the accidents of the direct-current line.
(2) The detection method of the direct-current line fault detection system effectively improves the detection accuracy, does not need to wait for the startup operation of the electric appliance and the debugging of various functions, reduces the detection time and improves the detection efficiency; the detection method of the direct current line fault detection system has strong operability and low energy consumption, and can realize effective adjustment of line faults.
Detailed Description
The present invention will be described in detail with reference to the following embodiments.
The invention relates to a direct-current line fault detection system which comprises a current acquisition module, a wireless communication module and a line fault analysis table; the current acquisition module transmits the detection information of the direct current line to the line fault analysis table through the wireless communication module.
Preferably, the current collection module is used for collecting data of the direct current line. The current acquisition module comprises a circular iron core current transformer, the circular iron core current transformer comprises a circular iron core, a secondary coil, an integrating circuit, a support and a porcelain insulator, the secondary coil comprises a measurement winding and a power supply winding, the measurement winding and the power supply winding are wound on the circular iron core, two ends of the measurement winding are connected with the integrating circuit, two ends of the power supply winding are connected with the integrating circuit, the circular iron core and the integrating circuit are both arranged in the support, and the support is arranged in the porcelain insulator; the bottom of the porcelain insulator is provided with a through hole.
Preferably, the round iron core current transformer is connected with a microprocessor through an integrating circuit. The microprocessor is model NRF 51822-QFAA-R.
The round iron core current transformer has the function that when the current is measured, the current needs to be converted into a more uniform current (the secondary rating of the current transformer is 5A or 1A) for facilitating secondary instrument measurement. The current transformer has the functions of current transformation and electric isolation. The current transformer is a sensor for acquiring current information of an electric primary loop by secondary equipment such as a measuring instrument and relay protection in an electric power system, converts high current into low current in proportion, is connected to a primary system on the primary side and is connected to the measuring instrument and the relay protection on the secondary side.
The direct current line fault detection system has the advantages that:
the fault of the direct current line can be accurately detected, and the corresponding adjustment can be conveniently made in time; the direct-current line fault detection system improves the detection efficiency, shortens the detection time and can effectively prevent and reduce the accidents of the direct-current line.
The detection method of the direct current line fault detection system comprises the following steps of firstly, collecting current fault information of a direct current line through a current collection module, and transmitting the current fault information to a line fault analysis table through a wireless communication module; and the line fault analysis station reads the data of the power transmission direct current line.
The detection method of the direct current line fault detection system has the advantages that:
the detection method of the direct current line fault detection system effectively improves the accuracy of detection, does not need to wait for the startup operation of an electric appliance and the debugging of various functions, reduces the detection time and improves the detection efficiency; the detection method of the direct current line fault detection system has strong operability and low energy consumption, and can realize effective adjustment of line faults.