AU2014100712A4 - A new intelligent transformer and its application method - Google Patents

Abstract

Abstract The present invention relates to an electric power industry device, especially to a new intelligent transformer and its application method. It comprises a transformer and an information acquisition converter, wherein the transformer is provided with a UHF sensor 5 on the inner wall, an ultrasonic sensor at each inner apex, a vibration sensor at the lower clamp member and a stress sensor respectively on the upper and lower core; the ground lead of the core is provided with an HFCT sensor; and the sensor signal line is connected to the lead terminal at the top of the transformer. The new intelligent transformer of the present invention can realize real-time monitoring of working conditions, correctly judge 10 the operation state of transformer and realize intelligent transformer. Hvmm A0129732393-vl 120457054 Drawings Sensor state ollection unit on-electricity ollection unit Figure 1

Description

AUSTRALIA Patents Act 1990 ORIGINAL COMPLETE SPECIFICATION INNOVATION PATENT Invention title: A new intelligent transformer and its application method The following statement is aq full description of this invention, including the best method of performing it known to us: Hymm A0129731897-vl 120457054 -1- A New Intelligent Transformer and Its Application Method This is a divisional application divided out of international application No PCT/CN2013/085852, the entire contents of which are incorporated herein by reference. Technical Field 5 The present invention relates to an electric power industry device, especially to a new intelligent transformer and its application method. Background of the Art The important strategic direction for future development of China's power grid is to build information-based, automatic, digital, interactive, innovative, global-leading, unified, strong and 10 smart grid by relying on advanced materials, communications, information and control technology so as to achieve a wide range of optimal allocation of energy resources, promote intensive development of renewable energy and safeguard China's energy security. As an important part of the grid, the intelligence level of transformer determines the intelligence level of the entire grid. 15 According to the needs for building strong and smart grid, intelligent transformation is performed on some old grid devices. The new devices are also configured with smart components to realize intelligent transformer. However, most of the existing intelligent technology realizes real-time assessment of the operating status of the devices through installation of sensors in the external part of the transformer and monitoring of device status 20 parameters collected by monitoring device. The existing power transformer on-line monitoring system has different platforms, application systems and data formats, without standardized, normalized or unified architecture so that it is difficult to be promoted and implemented. Meanwhile, many systems are featured in single sensor, poor accuracy and reliability, high system false alarm rate and low status assessment reliability. Transformer intelligent components 25 realize modular design of multiple state parameter monitoring devices on a unified platform to achieve standardized and normalized data. However, the poor accuracy and reliability due to external environment interference and many other factors is still not resolved. With the development of intelligent electrical equipment, the integration of primary and secondary devices is the future development trend of smart high-voltage electrical equipment. 30 The electrical equipment can realize visualization, networking control and automation of the HymmA0129731897-vl 120457054 -2state by state perception and instruction components. Wherein, the sensor embedding technology is the key technology for development of smart electric appliances. Embedded sensor is pre-embedded in the device in the process of manufacturing primary devices and is connected with external devices by reserved interface for intuitive and real reflection of the situation inside 5 the device. Meanwhile, it can avoid the external environment impact and improve the accuracy of the sensor. Currently, some primary equipment manufacturers are trying to implant a sensor into the primary device. For example, embedded fiber bragg gratings, direct measurement of the temperature and stress inside the windings, temperature measurement by optical fiber cable, sensor embedded in circuit breaker and so on. However, there is no in-depth study of embedded 10 sensor technology of transformer or new intelligent transformer based on embedded sensing technology composed of corresponding information acquisition system. Summary of the Invention The present invention is aimed to overcome the disadvantages of the prior arts to provide a new intelligent transformer for real-time monitoring of working conditions, correctly judging the 15 operation state of transformer and realizing intelligent transformer. The present invention also provides a method for the application of the new intelligent transformer. To solve the above technical problems, the technical solution of the present invention is as follows: a new intelligent transformer, comprising a transformer and an information acquisition converter, wherein the transformer is provided with a UHF sensor on the inner wall, an ultrasonic 20 sensor at each inner apex, a vibration sensor at the lower clamp member and a stress sensor respectively on the upper and lower core; the ground lead of the core is provided with an HFCT sensor; and the sensor signal line is connected to the lead terminal at the top of the transformer. Further, there are 4 said UHF sensors, which are disposed on the four sides of the transformer; there are 8 said ultrasonic sensors, which are provided in the eight inner apexes of 25 the transformer; there are 8 vibration sensors, which are respectively provided on the four sides of the lower clamp member; there are 6 said stress sensors, 3 of which are installed on the upper portion of the transformer core and the remaining of which are installed on the lower portion of the transformer core. Further, the information acquisition converter includes a sensor state acquisition unit, an 30 electricity acquisition unit and a non-electricity acquisition unit. HymmA0129731897-vl 120457054 -3 - Further, the sensor state acquisition unit includes a high-speed acquisition unit for collecting UHF sensor signal, HFCT sensor signal and ultrasonic sensor signal and a normal acquisition unit for collecting vibration sensor signal and stress sensor signal. Further, the information acquisition converter further comprises a data analysis unit, a 5 warning unit, a data conversion unit and a data transmission unit. An application method of a new intelligent transformer comprises the following steps: (a) Data acquisition: The information acquisition converter collects electricity information and non-electricity information of the transformer and signal of all sensors; (b) Data analysis: The data analysis unit analyzes and processes the data collected by 10 information acquisition converter; in case of fault, it will start warning unit for early warning; (c) Data conversion: The data conversion unit converts the data collected by the information acquisition converter into information in line with IEC61850 standard; (d) Data transmission: The data transmission unit transmits information converted by the data conversion unit to the remote monitoring system. 15 Further, the application method of a new intelligent transformer further comprises the steps of acquisition interval setting and mode determination, which are performed before step (a), wherein: The acquisition interval setting step specifically includes: setting the time interval of sensor state acquisition unit, the electricity acquisition unit and non-electricity acquisition unit, wherein 20 the interval is 5 minutes at least and up to 24 hours at most; The operation mode judging step includes the following specific steps: judging whether the transformer is in normal mode; if so, performing step (a) where information acquisition converter collects electricity information and non-electricity information of the transformer and signal of all sensors according to the time interval set in the step of acquisition interval setting; If 25 the transformer is not in normal mode, immediately proceeding step (a) where the information acquisition converter immediately collects electricity information and non-electricity information of the transformer and signal of all sensors. Further, the time interval of the sensor state acquisition unit, the electricity acquisition unit and non-electricity acquisition unit is set to 15 minutes. Too long time interval is not conducive HymmA0129731897-vl 120457054 -4to the timely reporting of the transformer status and faults but too short interval results in large data processing capacity and high power consumption. Through repeated comparison and practice of the inventor, the interval is properly 15 minutes, which is acceptable to report the fault delay. Therefore, such time interval can keep abreast of the transformer state and find the 5 fault in time to avoid greater damage. It also reduces the amount of data processing to some extent, reduces the power consumption of the sensor and corresponding devices as well as save resource to a certain extent. Comparison with the prior art, the beneficial features of the present invention are as follows: 10 1) The new intelligent transformer is embedded with many types of sensors such as UHF, ultrasound, vibration, stress, HFCT sensor and so on. The signal of all kinds of sensors is led out through the lead terminals at the top of the transformer. Multi-function and multi-channel transformer state information acquisition converter is configured according to the features of all kinds of signal to directly convert various physical signals into digital signal. According to the 15 preset transformer state analysis and fault diagnosis model, the device state is identified. According to identification results, various state parameter information is recorded in case of abnormity or fault of the transformer so as to reflect the internal condition of the device in an intuitive and real manner, avoid the impact of the external environment and improve the accuracy of the sensor; 20 2) The new intelligent transformer is embedded with a sensor to achieve in-depth understanding of the operational status of the transformer, real-time monitoring of the working conditions, properly judgment of the operation state of the transformer and achievement of intelligent transformer. Brief Description of Drawings 25 Figure 1 is the schematic diagram of the overall structure of the present invention; Figure 2 is the schematic diagram of the structure of the sensor of the present invention; Figure 3 is the schematic diagram of the information acquisition converter of the present invention; Wherein: 1-Transformer; 2-information acquisition converter; 3-Tank; 4-lead terminal; 30 5-low-pressure casing; 6-high-pressure casing; 7-high-voltage winding; 8-core; 9-core grounding HymmA0129731897-vl 120457054 -5lead; 10-upper clamp member; 11-low-voltage winding; 12-pad; 13-lower clamp member; 14-UHF sensor; 15-ultrasonic sensor; 16-vibration sensor; 17-stress sensor; 18-HFCT sensor; 19-lead. Embodiments 5 The following drawings and specific embodiments are for further details of the present invention. Please refer to Figure 1 and 2. The present invention relates to a new intelligent transformer. It comprises a transformer 1 and an information acquisition converter 2, wherein the transformer 1 is provided with a UHF sensor 14 on the inner wall, an ultrasonic sensor 15 at each inner apex, 10 a vibration sensor 16 at the lower clamp member 13 and a stress sensor 17 respectively on the upper and lower core 8; the ground lead 9 of the core is provided with an HFCT sensor 18; and the sensor signal line is connected to the information acquisition converter 2 by the lead terminal 4 at the top of the transformer 1. The information acquisition converter 2 includes a sensor state acquisition unit, an electricity acquisition unit and a non-electricity acquisition unit. The sensor 15 state acquisition unit includes a high-speed acquisition unit for collecting UHF sensor signal, HFCT sensor signal and ultrasonic sensor signal and a normal acquisition unit for collecting vibration sensor signal and stress sensor signal. The information acquisition converter 2 converts the information collected into information in line with IEC61850 standard; Please refer to Figure 1, 2 and 3; the embodiment of the present invention is composed of 20 two parts: the transformer embedded with UHF sensor 14, ultrasonic sensor 15, vibration sensor 16, stress sensor 17 and HFCT sensor 18 and the information acquisition converter 2. Various types of sensors embedded inside the transformer 1 are used for monitoring and collecting various types of state information inside the transformer in a real-time manner and leading out various types of sensor signal through the leading casing set aside at the top of the transformer 1. 25 Various types of sensor signal led from the top is collected on the information acquisition converter 2 near the transformer 1. The information acquisition converter 2 is divided into high-speed acquisition card (i.e., high-speed acquisition unit) and normal acquisition card (i.e. normal acquisition unit) according to different signal bandwidth. Different acquisition cards of the information acquisition convert 2 complete acquisition of physical signal and convert them 30 into digital signal and then converted into data in line with IEC61850 standard through various data conversion models embedded in the information acquisition converter 2 to be directly output to the substation state monitoring system for real-time sensing of transformer state. HymmA0129731897-vl 120457054 -6- In the embodiment of the present invention, the inner wall of the transformer is provided with four UHF sensors for monitoring high-frequency signal generated from internal discharge of the transformer, thus monitoring the generation of partial discharge site inside the transformer. In the embodiment of the present invention, the upper and lower 8 vertex corners in the 5 transformer are provided with ultrasonic sensors. In case of partial discharge of the transformer, such 8 sensors can perform precise positioning of the discharge portions, thereby determining the position of partial discharge in the transformer. In the embodiment of the present invention, the lower clamp member of inner core of the transformer is provided with four vibration sensors for collecting vibration signal from 10 transformer core. Through the monitored abnormal vibration signal from the transformer, the transformer faults can be determined, such as over-excitation, over-voltage, core resonance and so on. In the embodiment of the present invention, the upper and lower portions of the transformer core are provided with six stress sensors for monitoring stress change of the transformer core so 15 as to determine the short-circuit current withstand capability of the transformer. In the embodiment of the present invention, the internal transformer core ground lead is provided with an HFCT sensor for monitoring the grounding current of the transformer core so as to determine the transformer core multi-point grounding fault and so on. In the embodiment of the present invention, the lead casing is reserved at the top of the 20 transformer for leading various types of signal lines of all internal sensors. In the embodiment of the present invention, the information acquisition converter deployed in the vicinity of the transformer collects various types of internal sensor signal and converts it to data in line with IEC61850 standard. In the embodiment of the present invention, the information acquisition model of the 25 information acquisition converter is divided into high-speed acquisition card and normal acquisition card according to different signal bandwidth. High-speed acquisition card is used for collecting UHF, HFCT and ultrasonic signal while normal acquisition card is used for collecting vibration and stress information. In the embodiment of the present invention, the information acquisition converter can 30 collect electricity and non-electricity information of the transformer and convert it into HymmA0129731897-vl 120457054 -7information in line with IEC61850 standard to achieve uniform acquisition of all the state information related to the transformer and the concentrated conversion. Refer to Figure 1. In the embodiment of the present invention, the signal line of the embedded sensor is connected to the information acquisition converter 2 through the lead 5 terminal 4 at the top of the transformer 1 and the information acquisition converter 2 is left with interface to access electricity and non-electricity information of the transformer 1. In the embodiments of the present invention, when the transformer with embedded sensor is connected to the grid, the information acquisition converter is deployed in the vicinity of the transformer to facilitate the acquisition of the outgoing signal from the internal sensor of the 10 transformer. After the transformer is energized, in the working process with load, a variety of sensors embedded in the transformer, based on different principles, collect their signal from the inside of the transformer to be transmitted to the external part of the transformer through the lead terminals at the top of the transformer. Wherein, four UHF sensors are distributed on the four sides inside the transformer for collecting the high-frequency signal generated by partial 15 discharge so as to determine the extent and type of internal discharge failure of the transformer and further determine the operation state of the transformer through subsequent analysis of the information acquisition converter. The ultrasonic sensors are located in the eight upper and lower vertices of the transformer for collecting the ultrasonic signal generated by the partial discharge so that the information acquisition converter can analyze the transformer partial discharge 20 location and determine the precise location of faults based on the arrival time difference for all ultrasonic signal to be sent to the sensors. Four vibration sensors are placed on the four sides of the lower clamp member of the core inside the transformer for collecting vibration signal of the transformer core so that the information acquisition converter can determine over-excitation, over voltage and core resonant failure and further determine the transformer fault type and 25 operating status based on analysis of the features of different vibration signal. Six stress sensors are located on the upper and lower portions of three pillars of the transformer core for monitoring stress change in the transformer core. Core stress change is caused by too high short circuit current due to sudden short-circuit fault of the transformer so that the force of the transformer coil on the core increases suddenly. The information acquisition converter can judge 30 the capability of withstanding short circuit current of the transformer by analyzing the stress change in the transformer core and judging the size and time for the transformer to withstand short-circuit current. One HFCT sensor is installed in the core grounding lead wire inside the transformer for monitoring the grounding current of the transformer core so that the information HymmA0129731897-vl 120457054 - 8 acquisition converter can determine transformer core multi-point grounding failure and so on based on change of HFCT current signal. In the embodiment of the present invention, the sensor wiring led from the top of the transformer is collected in the information acquisition converter near the transformer to collect 5 and process all internal sensor information on the same hardware platform. Information acquisition converter is divided into high-speed acquisition card and normal acquisition card, wherein high-speed acquisition card adopts the high-performance chip to acquisition high-bandwidth signal. The high-speed acquisition card of this set of device is used for collecting four loops of UHF sensor signal, 8 loops of ultrasonic sensor signal and one loop of HFCT 10 sensor signal; and the normal acquisition card is used for collecting four loops of vibration sensor signal and 6 loops of stress sensor signal. Meanwhile, information acquisition converter can also collect related electricity and non-electricity information so as to collect all the information related to the state of the transformer. Information acquisition converter further includes a data analysis unit, a warning unit, a data conversion unit and a data transmission unit. 15 The preset state analysis and diagnosis model inside the device can analyze and process the data to extract the effective state parameters. The analysis and diagnosis model performs warning of device faults according to single-parameter of each sensor and performs assessment and diagnosis of the state of the transformer according to multiple state parameters. Meanwhile, it can convert all the relevant state information (electricity, non-electricity and sensor) to 20 information in line with IEC61850 standard to be uploaded to station monitoring system or grid evaluation center for advanced analysis and application by other systems. In the embodiment of the present invention, the data acquisition mode of the information acquisition converter is divided into two types: normal mode and fault mode. Under normal circumstances, the information acquisition converter collects information of sensors, electricity 25 and non-electricity at a fixed interval, which can be set from 5 minutes to 24 hours. Fault mode refers to that the information acquisition converter immediately operates when the fault diagnosis system inside the device identifies a transformer failure or impending failure, so as to record the change of all sensor parameters, electricity and non-electricity information in the whole fault process in order to fully record all state parameters in the whole fault process and 30 provide detailed data support for the subsequent data analysis and fault diagnosis. In the embodiment of the present invention, the data can be converted through the appropriate conversion modules into data in line with IEC61850 standard. Those output from HymmA0129731897-vl 120457054 -9transformer state information acquisition converter are standard state parameters and can be used directly by substation automation system and equipment state monitoring system. The present invention conforms to the development of the smart grid and meets the requirements of the smart grid construction for smart appliances. 5 In the embodiment of the present invention, an application method of a new intelligent transformer comprises the following steps: (1) The step of setting acquisition interval, specifically including: setting the time interval of sensor state acquisition unit, the electricity acquisition unit and non-electricity acquisition unit, wherein the interval is 5 minutes at least and up to 24 hours at most; and the acquisition interval 10 of this embodiment is set to 15 minutes; (2) The step of judging the operation mode: judging whether the transformer is in normal mode; if so, the information acquisition converter collects electricity information and non-electricity information of the transformer and signal of all sensors according to the time interval set in the step of acquisition interval setting, namely that the high-speed acquisition card 15 is used for collecting four loops of UHF sensor signal, 8 loops of ultrasonic sensor signal and one loop of HFCT sensor signal; and the normal acquisition card is used for collecting four loops of vibration sensor signal and 6 loops of stress sensor signal. The electricity acquisition unit and non-electricity acquisition unit respectively collect transformer-related electricity and non-electricity information once every 15 minutes and collect all the information related to the 20 state of the transformer in a unified manner. If the transformer is not in normal mode, the information acquisition converter immediately collects electricity information and non-electricity information of the transformer and signal of all sensors so as to record the change of all sensor parameters, electricity and non-electricity information in the whole fault process in order to fully record all state parameters in the whole fault process and provide detailed data support for the 25 subsequent data analysis and fault diagnosis. (3) Data analysis: The data analysis unit analyzes and processes the data collected by information acquisition converter; in case of fault, it will start warning unit for early warning; the preset state analysis and diagnosis model inside the data analysis unit can analyze and process the data to extract the effective state parameters. The analysis and diagnosis model performs 30 warning of device faults according to single-parameter of each sensor and performs assessment and diagnosis of the state of the transformer according to multiple state parameters; wherein the warning is completed by the warning unit. HymmA0129731897-vl 120457054 - 10 - (4) Data conversion: The data conversion unit converts the data (electricity, non-electricity and sensor) collected by the information acquisition converter into information in line with IEC61850 standard. The data conversion unit can be an Ethernet to IEC61850 protocol conversion gateway and can also be realized by other common IEC61850 protocol converters; 5 (5) Data transmission: The data transmission unit uploads the information in line with IEC61850 standard after converted by data conversion unit to station monitoring system or grid evaluation center and other remote monitoring systems for advanced analysis and application by other systems. Above is further details of the present invention with reference to specific embodiments but 10 it can not be considered that the specific embodiments of the present invention are only limited to such instructions. The ordinary technicians in the art to which the present invention pertains can also make a few simple deduction or replacement without departing from the concept of the present invention but all shall be considered as the protection scope of the present invention. 15 HymmA0129731897-vl 120457054 - 11 -

Claims (8)

1. A new intelligent transformer, comprising a transformer and an information acquisition converter, wherein the transformer is provided with a UHF sensor on the inner wall, an ultrasonic sensor at each inner apex, a vibration sensor at the lower clamp member and a stress sensor respectively on the upper and lower core; the ground lead of the core is provided with an HFCT sensor; and the sensor signal line is connected to the lead terminal at the top of the transformer.

2. The new intelligent transformer according to claim 1, wherein there are 4 said UHF sensors, which are disposed on the four sides of the transformer; there are 8 said ultrasonic sensors, which are provided in the eight inner apexes of the transformer; there are 8 vibration sensors, which are respectively provided on the four sides of the lower clamp member; there are 6 said stress sensors, 3 of which are installed on the upper portion of the transformer core and the remaining of which are installed on the lower portion of the transformer core.

3. The new intelligent transformer according to claim 1 or 2, wherein the information acquisition converter includes a sensor state acquisition unit, an electricity acquisition unit and a non-electricity acquisition unit.

4. The new intelligent transformer according to claim 3, wherein the sensor state acquisition unit includes a high-speed acquisition unit for collecting UHF sensor signal, HFCT sensor signal and ultrasonic sensor signal and a normal acquisition unit for collecting vibration sensor signal and stress sensor signal.

5. The new intelligent transformer according to claim 4, wherein the information acquisition converter further comprises a data analysis unit, a warning unit, a data conversion unit and a data transmission unit.

6. The application method of a new intelligent transformer according to claim 5, comprising the following steps: (a) Data acquisition: information acquisition converter collects electricity information and non-electricity information of the transformer and signal of all sensors; (b) Data analysis: The data analysis unit analyzes and processes the data collected by information acquisition converter; in case of fault, it will start warning unit for early warning; Hymm A0129732099-vl 120457054 - 12 - (c) Data conversion: The data conversion unit converts the data collected by the information acquisition converter into information in line with IEC61850 standard; (d) Data transmission: The data transmission unit transmits information converted by the data conversion unit to the remote monitoring system.

7. The application method of a new intelligent transformer according to claim 6, further comprising the steps of acquisition interval setting and mode determination, which are performed before step (a), wherein: The acquisition interval setting step specifically includes: setting the time interval of sensor state acquisition unit, the electricity acquisition unit and non-electricity acquisition unit, wherein the interval is 5 minutes at least and up to 24 hours at most; The operation mode judging step includes the following specific steps: judging whether the transformer is in normal mode; if so, performing step (a) where information acquisition converter collects electricity information and non-electricity information of the transformer and signal of all sensors according to the time interval set in the step of acquisition interval setting; If the transformer is not in normal mode, immediately proceeding step (a) where the information acquisition converter immediately collects electricity information and non-electricity information of the transformer and signal of all sensors.

8. The application method of a new intelligent transformer according to claim 7, wherein the time interval of the sensor state acquisition unit, the electricity acquisition unit and non-electricity acquisition unit is set to 15 minutes . Hymm A0129732099-v1 120457054 - 13-