CN106814234A - A kind of online 6/10KV voltage detectings sensor of non-intrusion type - Google Patents

Abstract

A non-invasive on-line 6/10KV voltage detection sensor relates to a voltage measurement device on a high-voltage transmission line and mainly includes a cylindrical conductor, a wire, and a sampling resistor. The invention proposes a sensor design based on coupling capacitance, which can realize non-invasive measurement of transmission line voltage, has good linearity, high measurement accuracy, low cost, convenient installation, high safety factor, real-time and accurate measurement, and timely detection of transformers And the potential safety hazards on the transmission line, good versatility and other characteristics. The invention can be widely applied to on-line monitoring of transmission lines, especially on-line monitoring of voltage on 6/10KV transmission lines.

Description

A non-invasive online 6/10KV voltage detection sensor

Technical field:

The invention relates to a detection device in the technical field of electric power systems, in particular to a non-invasive AC voltage measurement device used on high-voltage transmission lines.

Background technique:

The safe operation of the power system is closely related to people's lives. Once the power system fails, it will greatly threaten national security and the normal life of the people. Therefore, it is particularly important to safely and effectively detect whether the voltage on the transmission line is normal. At present, an important measure to detect whether the power system can operate normally is to monitor the voltage on the transformer transmission line in real time and effectively. The voltage detection on the 6/10KV power supply line is mostly fixed and contact measurement. This type of voltage sensor has many shortcomings, such as large size, inconvenient installation and movement, low measurement accuracy, and inability to realize online non-contact measurement. .

Existing non-contact voltage sensors, such as the "non-contact voltage measuring device" patent of patent No. CN 106030320A, calculate the actual voltage by the principle of inducing voltage next to the high-voltage wire. But the disadvantages are also obvious: when the measuring device is measuring, once its distance from the high-voltage wire changes, the corresponding induced voltage will also be different, resulting in errors or even wrong measurements, and the uncontrollable factors are too large. If there are too many, it may even cause failures not to be discovered in time due to measurement reasons, which poses a great threat to the safety of the country and people's property.

Invention content:

In order to overcome the deficiencies of the above-mentioned technologies, the present invention provides a non-invasive online 6/10KV voltage detection sensor. This voltage measurement sensor must be made into a standard part, which can be measured near the high-voltage transmission line or on the ground, and has the advantages of convenient measurement. , safe operation, high accuracy, easy to move, low cost, real-time online detection and other advantages.

The working principle of the present invention is: the voltage on the high-voltage transmission line is drawn out through a wire, and the wire and a cylindrical conductor with a fixed inner and outer diameter form an equivalent coupling capacitance, so that the value of the coupling capacitance can be calculated using the formula , and then the magnitude of the current flowing through the cylinder can be obtained. When the current flows through the sampling resistor, by reading the voltage on both sides of the resistor, the curve of the sampling voltage and the actual voltage is calibrated, and then the voltage on the actual transmission line is calculated from the voltage of the sampling resistor.

The present invention is realized through the following technical solutions: the present invention is a non-invasive on-line 6/10KV voltage detection sensor, which mainly includes a cylindrical conductor, a wire, and a sampling resistor. Its characteristics are:

The conductor is cylindrical, consisting of an outer cylinder and an inner cylinder, and an insulating substance is filled between the inner and outer cylinders as a medium, so that the cylinder is equivalent to a coupling capacitor; the length of the wire is arbitrary, but nested The length of the wire in the inner cylinder of the cylindrical conductor must be fixed, and the surface of the wire must have an insulating layer, so that the voltage on the terminal of the high-voltage transmission line can be introduced into the cylindrical conductor without loss; the sampling resistor must be a high-precision resistor. And the rated power must be large enough to represent the voltage on both sides of the sampling resistor as accurately as possible, so as to reflect the voltage on the transmission line and realize non-invasive measurement of the voltage on the transmission line.

After the present invention adopts above-mentioned technical scheme, mainly have following effect:

1. The present invention is a non-intrusive voltage measurement sensor made based on the principle of coupling capacitance. It measures the voltage non-invasively through the method of leading the voltage on the high-voltage transmission line with a wire, which has good linearity, high measurement accuracy, and low cost. Low and easy to install, you can take measurements anywhere.

2. High safety factor, real-time and accurate measurement can be realized, potential safety hazards on transformers and transmission lines can be found in time, good versatility, and provide ideas for safe measurement of high-voltage transmission lines in the future.

Description of drawings:

Fig. 1 is a structural representation of the present invention;

Fig. 2 is the equivalent circuit diagram of Fig. 1;

Figure 3 is a graph showing the relationship between the sampled voltage and the actual voltage.

detailed description:

In order to make the characteristics of the present invention clearer and easier to understand, the preferred embodiments are listed below. This embodiment is carried out on the premise of the technical solution of the present invention. The embodiments of the present invention will be described in detail below.

As shown in FIG. 1 , the embodiment of the present invention includes: a cylindrical conductor, a wire, and a sampling resistor. Among them, one end of the wire is connected to the high-voltage transmission line to lead out the high-voltage signal on the high-voltage transmission line, and the other end is introduced into the cylinder, and the length of the wire in the cylinder is fixed to eliminate the error caused by the uncertain position of the wire. In this way, the wire and the cylinder are equivalent to a coupling capacitor, as shown in the equivalent circuit in Figure 2, the sampling resistor must be a high-precision resistor, and the rated power must be large enough. In this embodiment, a high-precision resistor with a resistance value of 1KΩ is selected to accurately measure the voltage across it.

The following describes the implementation process of this embodiment by adding different voltages to the wires and simulating the change of the voltage at both ends of the sampling resistor under different voltage conditions. First, add a 10KV sinusoidal voltage to the wire, which will generate an induced current with the coupling capacitor equivalent to the cylinder, and read the voltage flowing through the sampling resistor. Keep all the conditions unchanged, only change the magnitude of the input voltage, record the sampling resistor voltage, measure multiple times, record the curve graph of the sampling voltage and the actual voltage, and calibrate the relationship expression between the sampling voltage and the actual voltage, as shown in Figure 3. In this way, when actually put into application, by reading the voltage at both ends of the sampling resistor, the actual voltage on the high-voltage transmission line can be obtained, thereby achieving the purpose of non-invasive voltage measurement.

Through the above embodiment and obtained results, it can be found that this embodiment can well summarize the specific content and advantages of the present invention, and is convenient for measurement and safe in operation, and can be widely used in the measurement of high-voltage transmission lines.

Claims (4)

1. a kind of online 6/10KV voltage detectings sensor of non-intrusion type, this voltage detecting sensor includes a cylinder Electric conductor, wire, sample resistance.It is characterized in that：Cylindrical conductive body and the wire drawn from ultra-high-tension power transmission line terminal A standard component is constituted, and position is relatively fixed, and eliminates due to the error that position reason is produced.Using electric conductor and electrified wire Coupled capacitor is internally formed in cylindrical conductive body, the voltage at sample resistance two ends is read by the electric current that induces, using taking The relation demarcated between sample voltage and virtual voltage represents transmission line of electricity virtual voltage size, realizes that non-intrusive measurement transformer is defeated Voltage purpose in electric line.

2. the online 6/10KV voltage detectings sensor of a kind of non-intrusion type according to claim 1, it is characterised in that：From The wire drawn on ultra-high-tension power transmission line, its length is any, but the conductor length for being nested in cylinder in cylindrical conductive body is necessary Fixed, conductive line surfaces must have insulating barrier, can be incorporated into the voltage on ultra-high-tension power transmission line terminal is loss-free cylinder and lead In electric body.

3. the online 6/10KV voltage detectings sensor of a kind of non-intrusion type according to claim 1, it is characterised in that：Lead Electric body is cylinder, is made up of outer barrel and inner cylinder, megohmite insulant is filled between inner/outer tube and serves as medium, is equivalent to the cylinder One coupled capacitor.

4. the online 6/10KV voltage detectings sensor of a kind of non-intrusion type according to claim 1, it is characterised in that：Take Sample resistance must be precision resister, and rated power must be sufficiently large, and sample resistance both sides are accurately represented as far as possible Voltage, so as to reflect virtual voltage size on transmission line of electricity, realizes voltage on non-intrusive measurement transmission line of electricity.