1. Field of the Invention
The present invention relates to safety devices for high-voltage equipment, and particularly to a monitoring and early warning alarm system for high voltage insulator failure that provides for transmission of an alarm signal when environmental conditions exceed pre-selected threshold values, indicating the likelihood of high voltage insulator failure.
2. Description of the Related Art
If one of the insulator units D in the string breaks, it can be replaced without discarding the entire string. Such insulating discs are typically constructed of a ceramic or glass disc with a metal cap and pin cemented on either side. In order to make defective units obvious, glass units are designed with “Class B” construction; i.e., an overvoltage causes a puncture arc through the glass. The glass is heat-treated so that it will shatter, making the damaged unit visible. However, since the mechanical strength of the unit is unchanged, the insulator string stays together. Standard disc insulator units are ten inches in diameter and approximately 5¾ inches long, and can support a load of approximately 80-120 kN, with a dry flashover voltage of about 72 kV, and are rated at an operating voltage of 10-12 kV. However, the flashover voltage of a string is less than the sum of its component discs, since the electric field is not distributed evenly across the string but, rather, is strongest at the disc nearest to the conductor, which will flashover first. Metal grading rings are sometimes added around the lowest disc in order to reduce the electric field across that disk and improve flashover voltage.
Detection of a failed insulator requires either visual inspection or disruption of the normal electrical power supply. In other words, failure must first occur before repairs can be made. It would be desirable to provide an early predictor for high voltage insulator failure, allowing repairmen to either already be on site when the insulator fails, in order to expedite repair time, or to allow repair and/or replacement of a faulty insulator before the failure actually occurs. Thus, a monitoring and early warning alarm system for high voltage insulator failure solving the aforementioned problems is desired.
The monitoring and early warning alarm system for high voltage insulator failure provides an early predictor for high voltage insulator failure, allowing repairmen to either already be on site when a high voltage insulator fails in order to expedite repair time, or allowing repair and/or replacement of a faulty insulator before the failure actually occurs. The monitoring and early warning alarm system for high voltage insulator failure transmits an alarm signal when environmental conditions exceed pre-selected threshold values, indicating the likelihood of high voltage insulator failure. The early warning alarm system includes a housing adapted for mounting on a high-voltage power line in proximity to a high voltage insulator associated with the high-voltage power line. Preferably, the housing is configured to simulate a conventional high voltage insulator string.
At least one sensor is mounted on the housing. The at least one sensor may be a temperature sensor for measuring ambient temperature, a contamination sensor for measuring ambient pollutant contamination, a humidity sensor for measuring ambient humidity, or combinations thereof. The contamination sensor preferably includes at least one dust sensor. The measured ambient temperature, pollutant contamination and humidity are processed into respective data signals by a conditioning circuit, and then fed to a controller. The controller compares the measured ambient temperature, the measured humidity and the measured ambient pollutant contamination with pre-selected threshold values of temperature, humidity and pollutant contamination.
A transceiver mounted on the housing transmits an alarm signal when the measured ambient temperature, the measured humidity and/or the measured ambient pollutant contamination are greater than the pre-selected threshold values of temperature, humidity and pollutant contamination, respectively. The transceiver, controller, and sensors may be powered by one or more batteries contained within the housing, or, alternatively, by at least one solar cell or solar panel mounted on the exterior of the housing. It should be understood that in addition to providing an early warning alarm, the system is also a continuous monitoring system for potential high voltage insulator failure.
These and other features of the present invention will become readily apparent upon further review of the following specification.
Similar reference characters denote corresponding features consistently throughout the attached drawings.
The monitoring and early warning alarm system for high voltage insulator failure 10 provides an early predictor for failure of a high voltage insulator, such as the typical high voltage insulator I of
In addition to allowing repairmen to either already be on site when the high voltage insulator I fails in order to expedite repair time, or allowing repair and/or replacement of the faulty insulator I before the failure actually occurs, the early warning alarm system 10 is highly portable, allowing the system to be easily placed at differing areas of interest, as well as being easily transported, stored and replaced. As best shown in
At least one sensor is mounted on the housing 21. The at least one sensor may be a temperature sensor 22 for measuring ambient temperature, a contamination sensor 26 for measuring ambient pollutant contamination, a humidity sensor 24 for measuring ambient humidity, or combinations thereof. It should be understood that any suitable type of temperature sensor, humidity sensor or contamination/ambient pollution sensor may be utilized. The contamination sensor 26 preferably includes at least one dust sensor.
As illustrated in
A transceiver 30 mounted on the housing 21 transmits an alarm signal S when the measured ambient temperature, the measured humidity, and/or the measured ambient pollutant contamination are greater than the pre-selected threshold values of temperature, humidity and pollutant contamination, respectively. In
The transceiver 30, controller 18, and sensors 22, 24, 26 may be powered by one or more batteries contained within the housing 21, or, alternatively, by at least one solar cell 20 or solar panel mounted on the exterior of the housing 21. Alternatively, system 10 may be interconnected with the power line associated with the string of high voltage insulators.
It should be understood that the conditioning circuit 28, the controller 18, and the memory 19 may be associated with, or incorporated into, any suitable type of computing device, for example, a personal computer or a programmable logic controller. The conditioning circuit 28, the controller 18, the memory 19 and any associated computer readable recording media are in communication with one another by any suitable type of data bus, as is well known in the art.
Examples of computer-readable recording media include a magnetic recording apparatus, an optical disk, a magneto-optical disk, and/or a semiconductor memory (for example, RAM, ROM, etc.). Examples of magnetic recording apparatus that may be used in addition to memory 112, or in place of memory 112, include a hard disk device (HDD), a flexible disk (ED), and a magnetic tape (MD. Examples of the optical disk include a DVD (Digital Versatile Disc), a DVD-RAM, a CD-ROM (Compact Disc-Read Only Memory), and a CD-R (Recordable)/RW.
It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims.