阅读说明：本技术 包括温度分布确定装置的高压系统 (High-pressure system comprising a temperature distribution determining device ) 是由 T·兰里德 J·施斯琳 于 2020-02-28 设计创作，主要内容包括：包括温度分布确定装置的高压系统。一种高压系统(9),包括：高压套管(5),其具有配置为与填充有介电液体(3b)的箱(3a)组装在一起的套管本体(5a),其中,套管本体(5a)具有腔体(5b),并且套管(5)包括介电液位传感器(5f),该介电液位传感器被配置为测量腔体(5b)中的介电液位(11)；以及温度分布确定装置(7),其被配置为基于由介电液位传感器(5f)测量到的介电液位(11)确定套管(5)中的热分布。(High-pressure system comprising a temperature distribution determining device. A high-pressure system (9) comprising: a high voltage bushing (5) having a bushing body (5a) configured to be assembled with a tank (3a) filled with a dielectric liquid (3b), wherein the bushing body (5a) has a cavity (5b) and the bushing (5) comprises a dielectric liquid level sensor (5f) configured to measure a dielectric liquid level (11) in the cavity (5 b); and a temperature distribution determination device (7) configured to determine a thermal distribution in the casing (5) based on the dielectric level (11) measured by the dielectric level sensor (5 f).)

1. A high-pressure system (9) comprising:

a high voltage bushing (5) having a bushing body (5a) configured to be assembled with a tank (3a) filled with a dielectric liquid (3b), wherein the bushing body (5a) has a cavity (5b) and the bushing (5) comprises a dielectric liquid level sensor (5f) configured to measure a dielectric liquid level (11) in the cavity (5 b); and

a temperature distribution determination device (7) configured to determine a thermal distribution in the casing (5) based on the dielectric level (11) measured by the dielectric level sensor (5 f).

2. The high-voltage system (9) as claimed in claim 1, wherein the bushing body (5a) has a box end (5d) provided with an opening (5e) into the cavity (5 b).

3. The high voltage system (9) as claimed in claim 1 or 2, wherein the temperature distribution determining means (7) is configured to receive a current value of the current through the bushing (5), wherein the temperature distribution determining means (7) is configured to determine the temperature distribution also based on the current value.

4. The high voltage system (9) as claimed in any of the preceding claims, wherein the temperature distribution determining device (7) is configured to obtain an ambient air temperature (T1) of the ambient air surrounding the bushing (5), wherein the temperature distribution determining device (7) is configured to determine the temperature distribution also based on the ambient air temperature (T1).

5. The high pressure system (9) as claimed in any of the preceding claims, wherein the temperature distribution determining device (7) is configured to obtain a dielectric liquid temperature (T2) of the dielectric liquid in the tank (3a), wherein the temperature distribution determining device (7) is configured to determine the temperature distribution also based on the dielectric liquid temperature (T2).

6. The high voltage system (9) as claimed in any of the preceding claims, wherein the temperature distribution determining means (7) comprises a mathematical model of the bushing (5), wherein the temperature distribution determining means (7) is configured to determine the temperature distribution in the bushing (5) using the mathematical model.

7. The high voltage system (9) as claimed in claim 6, wherein the mathematical model is based on the geometry of the bushing (5) and takes into account weather conditions.

8. The high voltage system (9) as claimed in claim 7, wherein the mathematical model is further based on the bushing (5) comprising a resin impregnated material.

9. The high voltage system (9) as claimed in any of the preceding claims, wherein the bushing (5) is a dry bushing.

10. The high voltage system (9) according to any of the preceding claims, wherein the bushing (5) is a resin impregnated bushing.

11. A high-voltage electromagnetic induction system (1) comprising:

the high-pressure system (9) as claimed in any of claims 1 to 10, and

-an electromagnetic induction device (3) comprising a tank (3a) filled with a dielectric liquid (3b), wherein the bushing (5) is assembled with the tank (3 a).

12. A method of determining a temperature distribution in a high voltage bushing (5) assembled with a tank (3a) filled with a dielectric liquid (3b), wherein the bushing (5) has a bushing body (5a) with a cavity (5b) and the bushing (5) comprises a dielectric liquid level sensor (5f) configured to measure a dielectric liquid level (11) in the cavity (5b), wherein the method comprises:

a) acquiring a dielectric liquid level (11) in the cavity (5b) as measured by the dielectric liquid level sensor (5f), an

b) Determining a temperature distribution in the casing (5) based on the dielectric liquid level (11).

13. The method according to claim 12, comprising obtaining a current value of the current through the casing (5), wherein step b) is further based on the current value.

14. The method according to claim 12 or 13, comprising obtaining an ambient air temperature (T1) of ambient air surrounding the casing (5), wherein step b) is further based on the ambient air temperature.

15. The method according to any one of claims 12 to 14, comprising obtaining a dielectric liquid temperature (T2) of the dielectric liquid (3b) in the tank (3a), wherein step b) is further based on the dielectric liquid temperature (T2).

Technical Field

The present disclosure generally relates to a high-pressure system. In particular, the present disclosure relates to a high voltage system comprising a high voltage bushing.

Background

High voltage bushings are sensitive to operating temperatures. The temperature sensor may provide only partial knowledge in close proximity to the sensor, which may not represent the entire casing. There are also practical problems related to mounting temperature sensors near the most critical areas where temperature level information is of most concern. The sensor itself may cause additional points of failure of the casing, thereby defeating the purpose of the sensor. Even more serious difficulties arise if a plurality of temperature sensors are to be installed.

Various publications such as JP2008039683A and JPs6363923A disclose oil filled casings provided with a device for detecting the oil level in the casing.

Casing oil level is considered critical for the continuous short-term operation of oil filled casings in which oil circulates within the casing. The lowered oil level may then prevent oil circulation and quickly cause overheating. Oil may also be required for electrical resistance.

For dry bushings, the oil level is not important for the continued short-term operation of the bushing. The oil is not considered part of the bushing, but since the bushing is connected to the transformer tank and is in fluid communication with the oil in the tank, the bushing will be at least partially filled with oil.

Disclosure of Invention

A clear understanding of the condition of the casing requires a detailed knowledge of the temperature distribution within the casing. For example, the voltage at the measurement tap of the resin impregnated bushing can be used to detect partial breakdown between the foils and predict the impending breakdown, but the accuracy is based on knowledge of the temperature distribution.

In view of the above, it is an object of the present disclosure to provide a high voltage system that solves or at least mitigates the problems of the prior art.

Thus, according to a first aspect of the present disclosure, there is provided a high voltage system comprising: a high voltage bushing having a bushing body configured to be assembled with a tank filled with a dielectric liquid, wherein the bushing body has a cavity and the bushing comprises a dielectric liquid level sensor configured to measure a dielectric liquid level in the cavity; and a temperature distribution determination device configured to determine a thermal distribution in the casing based on the dielectric level measured by the dielectric level sensor.

Due to the estimated temperature distribution in the casing, an improved condition monitoring of the casing may be obtained.

Furthermore, since an estimate of the temperature distribution in the casing can be obtained at a given time (e.g., in real time), the rating of the casing can be viewed as a dynamic rather than a traditional static view. This is because the amount of current allowed through the bushing is dependent on the temperature in the bushing. For example, if the estimated temperature distribution at a time reflects a relatively low temperature in the casing, more current may be passed through the casing at that time than allowed by the conventional rating of the casing. The grid operator may thus be able to use the estimated temperature distribution in the bushing that is favorable for him when operating the grid.

The dielectric level sensor may for example be one of an ultrasonic sensor, a capacitive sensor, a float device, a fiber optic sensor or an isostatic pressure sensor, the position of which float device may be determined with respect to a receiver mounted at e.g. the top or bottom of the casing.

According to one embodiment, the sleeve body has a box end provided with an opening into the cavity. The sleeve is thus in fluid communication with the interior of the tank. Thus, dielectric liquid from the tank can flow into the bushing.

According to an embodiment, the temperature distribution determining means is configured to receive a current value of the current through the bushing, wherein the temperature distribution determining means is configured to determine the temperature distribution further based on the current value.

According to an embodiment, the temperature distribution determining means is configured to obtain an ambient air temperature of the ambient air surrounding the casing, wherein the temperature distribution determining means is configured to determine the temperature distribution also based on the ambient air temperature.

According to an embodiment, the temperature distribution determining means is configured to obtain a dielectric liquid temperature of the dielectric liquid in the tank, wherein the temperature distribution determining means is configured to determine the temperature distribution also based on the dielectric liquid temperature.

According to an embodiment, the temperature distribution determining means comprises a mathematical model of the casing, wherein the temperature distribution determining means is configured to determine the temperature distribution in the casing using the mathematical model.

According to one embodiment, the mathematical model is based on the geometry of the casing and takes into account weather conditions.

The geometry of the casing may for example comprise the casing length, the casing diameter and/or the installation angle, e.g. the angle of the central axis of the casing with respect to a horizontal or vertical plane.

The weather conditions may, for example, include one or more of ambient air temperature, wind speed, and precipitation.

The mathematical model may take into account the conductor type of the bushing.

According to an example, the mathematical model may be configured to receive input data in the form of a temperature of a dielectric liquid in the tank and/or a current flowing through the casing, in particular through a conductor of the casing.

According to one embodiment, the mathematical model is further based on the sleeve comprising a resin impregnated material.

According to one embodiment, the bushing is a dry bushing.

According to one embodiment, the sleeve is a resin impregnated sleeve. The sleeve may be, for example, a resin impregnated paper sleeve or a resin impregnated synthetic sleeve.

According to a second aspect of the present disclosure, there is provided a high voltage electromagnetic induction system comprising: a high voltage system according to the first aspect, and an electromagnetic induction device comprising a tank filled with a dielectric liquid, wherein the bushing is assembled with the tank.

The electromagnetic induction device may be, for example, a transformer or a reactor.

The dielectric liquid in the tank may be, for example, a mineral oil, a synthetic ester, a natural ester, or an isoparaffinic liquid.

According to a third aspect of the present disclosure, there is provided a method of determining a temperature distribution in a high voltage bushing assembled with a tank filled with a dielectric liquid, wherein the bushing has a bushing body having a cavity and the bushing comprises a dielectric liquid level sensor configured to measure a dielectric liquid level in the cavity, wherein the method comprises: a) acquiring a dielectric level in the cavity measured by the dielectric level sensor, and b) determining a temperature distribution in the bushing based on the dielectric level.

One embodiment comprises obtaining a current value of the current through the casing, wherein step b) is further based on the current value.

One embodiment comprises obtaining an ambient air temperature of ambient air surrounding the casing, wherein step b) is further based on the ambient air temperature.

One embodiment comprises obtaining a dielectric liquid temperature of the dielectric liquid in the tank, wherein step b) is further based on the dielectric liquid temperature.

In general, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to "a/an/the element, device, component, means" and the like are to be interpreted openly as referring to at least one instance of the element, device, component, means and the like, unless explicitly stated otherwise.

Drawings

Specific embodiments of the inventive concept will now be described, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 schematically illustrates a cross-sectional view of an example of a high-voltage electromagnetic induction system;

fig. 2 is a schematic block diagram of a temperature distribution determining apparatus; and

fig. 3 is a flow chart of a method of determining a temperature distribution in a high voltage bushing.

Detailed Description

The present inventive concepts will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments are shown. The inventive concept may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided by way of example so that this disclosure will be thorough and complete, and will fully convey the scope of the inventive concept to those skilled in the art. Like numbers refer to like elements throughout.

Fig. 1 depicts an example of a high voltage electromagnetic induction system 1. The exemplary high voltage electromagnetic induction system 1 comprises an electromagnetic induction device 3, a high voltage bushing 5 and a temperature distribution determining device 7. The high voltage bushing 5 and the temperature distribution determining means 7 form a high voltage system 9.

The electromagnetic induction device 3 is a high-voltage electromagnetic induction device 3. The electromagnetic induction device 3 may be, for example, a transformer or a reactor. The electromagnetic induction device 3 has a case 3 a. The electromagnetic induction device 3 may also include electromagnetic components such as a magnetic core, a yoke holding the magnetic core, one or more windings wound around one or more branches of the magnetic core, and a solid electrical insulator (not shown). The electromagnetic induction device 3 includes a dielectric liquid 3 b. The tank 3a is typically filled with a dielectric liquid 3 b.

The high voltage bushing 5 is advantageously a dry bushing, such as a resin impregnated paper or a synthetic bushing. The high voltage bushing 5 is configured to be mounted in the case 3 a. The high voltage bushing 5 may, for example, have a flange by means of which it may be mounted to the tank 3 a. The tank 3a has a tank opening configured to receive a portion of the high voltage bushing 5.

The high voltage bushing 5 has a bushing body 5 a. The sleeve body 5a may for example be provided with the aforementioned flange. The sleeve body 5a has a cavity or inner space 5 b. The sleeve body 5a is generally elongate, such as generally cylindrical. The high voltage bushing 5 further has a conductor 5c extending through the bushing body 5 a. The cavity 5b may be formed to surround the conductor 5 c. In some examples, the conductor 5c may be hollow, and the cavity 5b may extend inside the hollow conductor 5 c.

The sleeve body 5a has a box end 5d configured to be received by the box 3 a. According to an exemplary high voltage bushing 5, the box end 5d is provided with an opening 5 e. The conductor 5c may extend through the opening 5e into the tank 3 a. The opening 5e opens into the cavity 5 b. To this end, when the high voltage bushing 5 is mounted in the tank 3a, the cavity 5b is in fluid communication with the interior of the tank 3 a. When the high voltage bushing 5 is mounted in the tank 3a, the dielectric liquid 3b in the tank 3a flows into the cavity 5b of the bushing body 5 a. Thus, since the dielectric liquid 3b has flowed from the tank 3 into the bushing body 5a via the opening 5e, the dielectric liquid level 11 will normally be present at any time in the cavity 5 b.

The high voltage bushing 5 comprises a dielectric level sensor 5 f. The dielectric level sensor 5f is configured to measure the dielectric level 11 in the cavity 5 b. Any suitable dielectric level sensor may be used for this purpose.

The temperature distribution determining device 7 is configured to receive the dielectric level measurement from the dielectric level sensor 5 f. The temperature distribution determining means 7 is configured to determine the temperature distribution in the high voltage bushing 5 based on the dielectric level measurement. This determination is an estimate of the temperature distribution in the high voltage bushing 5. The temperature distribution may for example be along the axial direction of the high voltage bushing 5 and/or along the radial direction of the high voltage bushing 5.

In the example shown in fig. 1, the temperature distribution determining means 7 is arranged remote from the high voltage bushing 5 and the electromagnetic induction means 3, but may alternatively be mounted on the high voltage bushing 5 or on the electromagnetic induction means 3. In the present example, the temperature distribution determining device 7 is configured for wireless communication with the high voltage bushing 5 (e.g. the dielectric level sensor 5f), but may alternatively or additionally be arranged in a wired connection with the high voltage bushing 5.

Fig. 2 schematically shows a block diagram of an example of the temperature distribution determining apparatus 7. The temperature distribution determining means 7 may comprise a processing circuit 13 and a storage medium 15.

The processing circuitry 13 may, for example, use any combination of one or more of a suitable Central Processing Unit (CPU), multiprocessor, microcontroller, Digital Signal Processor (DSP), Application Specific Integrated Circuit (ASIC), Field Programmable Gate Array (FPGA), etc., and may be capable of performing any of the operations disclosed herein with respect to determining a temperature profile in the high voltage bushing 5.

The storage medium 15 may be embodied, for example, as a memory such as a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM) or an electrically erasable programmable read-only memory (EEPROM), and more particularly as a non-volatile storage medium in an external memory of the apparatus such as a USB (universal serial bus) memory or a flash memory such as a compact flash memory.

According to an example, the temperature distribution determining means 7 may be implemented as a cloud solution. Up to this point, according to a variant, the operations disclosed herein with respect to determining the temperature distribution in the high voltage bushing 5 may be performed partly or entirely in the cloud.

The temperature distribution determining device 7 may be configured to receive a current value of a current flowing through the conductor 5c of the high voltage bushing 5. In this case, the temperature distribution determining device 7 may be configured to determine the temperature distribution in the high-voltage bushing 5 also based on the current value. The current value may be obtained, for example, from a sensor such as a current transformer, or it may be estimated.

The temperature distribution determining means 7 may be configured to obtain an ambient air temperature T1 of the ambient air surrounding the high voltage bushing 5. In this case, the temperature distribution determining device 7 may be configured to determine the temperature distribution in the high voltage bushing 5 also based on the ambient air temperature T1. The ambient air temperature T1 may be obtained, for example, from a local temperature sensor, from a weather station, or from a weather forecast.

The temperature distribution determining means 7 may also be configured to obtain other weather condition data, such as current precipitation and wind speed. The precipitation and wind speed may be obtained, for example, from local sensors, from weather stations, or from weather forecasts. The temperature distribution determining means 7 may be configured to determine the temperature distribution in the high voltage bushing 5 also based on weather condition data, such as wind speed and/or precipitation.

The temperature distribution determining device 7 may be configured to acquire the dielectric liquid temperature T2 of the dielectric liquid 3b in the tank 3 a. In this case, the temperature distribution determining device 7 may be configured to determine the temperature distribution in the high voltage bushing 5 also based on the dielectric liquid temperature T2.

The measurement of the dielectric liquid temperature T2 may preferably be performed at a vertical position (e.g. at least 10mm from any loss generating component) corresponding to the point at which fluid communication between the high voltage bushing 5 and the tank 3a takes place.

The temperature distribution determining means 7 may comprise a mathematical model of the high voltage bushing 5. In particular, the storage medium 15 may contain a mathematical model, which is included in a computer program executable by the processing circuit 13. The mathematical model of the high voltage bushing may for example be based on the geometry of the bushing and/or the type of bushing, e.g. a dry resin impregnated bushing, in particular a resin impregnated paper/synthetic bushing. The mathematical model may be designed to use any of the above data (e.g. current value, ambient air temperature T1, weather conditions, and dielectric liquid temperature T2) as input data for determining the temperature distribution in the high voltage bushing 5.

Finite Element Methods (FEM) or similar methods may be used to determine the temperature distribution in the high voltage bushing 5 by finding one or more solutions to a mathematical model using inputs such as current values/currents through the conductor 5c, ambient air temperature T1 and/or air temperature inside the cavity in the high voltage bushing, measured dielectric liquid level, and dielectric liquid temperature T2, and boundary conditions.

Fig. 3 is a flow chart of a method for determining the temperature distribution in the high voltage bushing 5 by means of the temperature distribution determining means 7.

In step a), the dielectric level 11 measured by the dielectric level sensor 5f is acquired from the dielectric level sensor 5 f.

Additional data (such as any of weather condition data, current value of current through conductor 5c, ambient air temperature T1, and dielectric liquid temperature T2) may also be acquired in step a), although not necessarily simultaneously.

In step b), the temperature distribution in the high voltage bushing 5 is determined based on the dielectric level 11 measured by the dielectric level sensor 5 f.

In case any of the above additional data is acquired in step a), such data may also be used for determining the temperature distribution. The specific additional parameters used in the different embodiments (i.e. all or some of the additional data) are typically based on the implementation of the mathematical model and the desired accuracy of the estimated temperature distribution in the high voltage bushing 5. Using the dielectric liquid level, the ambient air temperature T1, the dielectric liquid temperature T2 in the tank 3a, the current value of the current flowing through the casing, and the wind speed and precipitation provides the most accurate estimate.

According to an example, the high voltage bushing 5 may comprise one or more temperature sensors. These temperature measurements may be used by the temperature distribution determining means 7 to adjust parameters of the mathematical model, such as the heat transfer coefficient to air. Such adjustment may be performed, for example, within a limited period of time. After the conditioning period, the temperature measurements may be used to identify an early warning of casing failure, e.g., if the measured temperature is higher than the corresponding mathematical model temperature, indicating an increase in loss that breakdown may occur. One or more temperature sensors may be designed to have a shorter life expectancy than the casing itself so that the casing may continue to operate reliably even if the sensors cease to operate after an adjustment period.

The inventive concept has mainly been described above with reference to a few examples. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the inventive concept, as defined by the appended claims.