Transient overvoltage detection system and method

Abstract

A detection system for detecting a transient overvoltage event in an electrical system operating at a system frequency includes an analog circuit connected to the electrical system and having a high pass filter operable to allow passage of a transient voltage signal having a signal frequency higher than the system frequency. The digital circuit includes: an analog-to-digital converter operative to convert a transient voltage signal to a digital transient voltage signal; and a microprocessor operable to receive the digital transient voltage signal, direct the digital transient voltage signal to a data storage device for storage in an overvoltage database, and reset the analog circuit. The computer system is operable to output data stored in the overvoltage database.

Description

Background Art

[0001] Current overvoltage detection systems are expensive and too slow to capture all the various transients that may occur. Some equipment cannot be monitored due to the cost of existing systems. Summary of the invention

[0002] In one aspect, a detection system for detecting transient overvoltage events in an electrical system operating at a system frequency includes an analog circuit connected to the electrical system and having a high pass filter operable to allow transient voltage signals having a signal frequency higher than the system frequency to pass through. A digital circuit includes an analog-to-digital converter and a microprocessor operable to convert the transient voltage signal into a digital transient voltage signal, the microprocessor operable to receive the digital transient voltage signal, direct the digital transient voltage signal to a data storage device for storage in an overvoltage database, and reset the analog circuit. A computer system operable to output the data stored in the overvoltage database.

[0003] On the other hand, a detection system for detecting transient overvoltage events in an electrical system operating at a system frequency includes an analog circuit connected to the electrical system and having a high-pass filter and a low-pass filter, the high-pass filter being operable to allow a transient voltage signal having a signal frequency higher than the system frequency to pass through, and the low-pass filter being operable to allow a system voltage signal at the system frequency to pass through. The detection system also includes a digital circuit having an analog-to-digital converter that operates to convert a transient voltage signal into a digital transient voltage signal and to convert a system voltage signal into a digital system voltage signal. A microprocessor is operable to receive a digital transient voltage signal and a digital system voltage signal, and compare the digital transient voltage signal and the digital system voltage signal to determine a phase angle of the system voltage signal when the transient voltage signal is generated. The microprocessor is also operable to determine an overvoltage value, direct the overvoltage value and the associated phase angle to a data storage device for storage in an overvoltage database, and reset the analog circuit. The detection system also includes a computer system that is operable to output data stored in the overvoltage database.

[0004] On the other hand, a method for detecting a transient overvoltage event in an electrical system operating at a system frequency includes: transmitting a signal from the electrical system to an analog circuit; filtering the signal to pass a first transient voltage signal having a signal frequency higher than the system frequency; and amplifying the first transient voltage signal. The method also includes: converting the first transient voltage signal to a digital transient voltage signal in a digital circuit; determining an overvoltage value of the digital transient voltage signal; storing the overvoltage value of the digital transient voltage signal; and resetting the analog circuit to allow the analog circuit to detect a second transient voltage signal.

[0005] The foregoing generally summarizes some technical features of the present disclosure so that those skilled in the art can better understand the following detailed description. Additional features and advantages of the present disclosure will be described below, and these features and advantages form the subject matter of the claims. Those skilled in the art will understand that they can easily use the disclosed concepts and specific embodiments as a basis for modifying or designing other structures for achieving the same purpose of the present disclosure. Those skilled in the art will also recognize that such equivalent constructions do not deviate from the spirit and scope of the broadest form of the present disclosure.

[0006] Additionally, before proceeding with the detailed description below, it should be understood that various definitions of certain words and phrases are provided throughout this patent document, which definitions, if not most, will apply to prior and future uses of such defined words and phrases in many, if not most, instances. Although certain terms may include a wide variety of embodiments, the appended claims may expressly limit such terms to specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] To easily identify the discussion of any particular element or activity, the most significant digit or digits in a reference number refer to the figure number in which the element is first introduced.

[0008] Figure 1 is a schematic diagram of an overvoltage detection system with a high-pass filter.

[0009] Figure 2 is a schematic diagram of another overvoltage detection system with a high-pass filter and a low-pass filter.

[0010] Figure 3 Yes Description Figure 1 and Figure 2 A flow chart of the operation of the overvoltage detection system.

[0011] Figure 4 It is presented Figure 1 and Figure 2 Image of the graphical user interface of the data collected by the overvoltage detection system.

[0012] Figure 5 is used with Figure 4 Image of the overvoltage detection system icon used together with the graphical user interface.

[0013] Figure 6 Yes Display Figure 2 Another graphical user interface image of the data collected by the overvoltage detection system. DETAILED DESCRIPTION

[0014] Before describing in detail any embodiment of the present invention, it should be understood that the application of the present invention is not limited to the construction details and component arrangements set forth in this specification or shown in the following drawings. The present invention can have other embodiments and can be implemented or executed in various ways. In addition, it should be understood that the words and terms used herein are for descriptive purposes only and should not be regarded as limiting.

[0015] Now, various techniques related to systems and methods are described with reference to the accompanying drawings, wherein the same reference numerals represent the same elements throughout the text. The drawings discussed below and the various embodiments used to describe the principles of the present disclosure in this patent document are for illustration only and should not be construed as limiting the scope of the present disclosure in any way. Those skilled in the art will appreciate that the principles of the present disclosure can be implemented in any appropriately arranged device. It should be understood that the functions described as being performed by certain system elements can be performed by multiple elements. Similarly, for example, an element can be configured to perform the functions described as being performed by multiple elements. The numerous innovative teachings of the present application will be described with reference to exemplary, non-restrictive embodiments.

[0016] It should be understood that the words or phrases used herein should be interpreted broadly unless explicitly limited in certain examples. For example, the terms "include", "have" and "include" and their derivatives are meant to include but are not limited to. Unless the context clearly indicates otherwise, the singular forms "one", "an" and "the" are intended to also include plural forms. In addition, the term "and / or" used herein refers to and covers any and all possible combinations of one or more of the listed associated items. Unless the context clearly indicates otherwise, the term "or" is inclusive and means and / or. The phrases "associated with..." and "associated with it" and their derivatives may mean including, included in, interconnected with, including, contained in, connected to, or connected with, coupled to, or coupled with, able to communicate, collaborate with, interlace, juxtapose, approach, bind to, or bind with, have, have the characteristics of, etc. In addition, although multiple embodiments or structures may be described here, any features, methods, steps, components, etc. described for one embodiment are also applicable to other embodiments if there is no specific description to the contrary.

[0017] In addition, although the terms "first", "second", "third", etc. may be used here to refer to various elements, information, functions or behaviors, these elements, information, functions or behaviors should not be limited by these terms. On the contrary, these numerical adjectives are used to distinguish different elements, information, functions or behaviors from each other. For example, the first element, information, function or behavior can be referred to as the second element, information, function or behavior, and similarly, the second element, information, function or behavior can also be referred to as the first element, information, function or behavior, without departing from the scope of this disclosure.

[0018] In addition, unless the context clearly indicates otherwise, the term "adjacent" may mean that one element is relatively close to another element, but not in contact with the other element, or that the element is in contact with other parts. In addition, unless otherwise clearly stated, the phrase "based on" is intended to mean "based at least in part on". The terms "approximately" or "substantially" or similar terms are intended to cover variations in the values ​​of the dimensions within normal industry manufacturing tolerances. If no industry standard is available, a twenty percent variation will fall within the meaning of these terms unless otherwise stated.

[0019] Electrical systems, such as power generation systems, grids, microgrids, etc., generate or use electrical power provided at system voltage and system frequency. These systems are often located and arranged to be susceptible to disturbances that may generate high frequency (i.e., above system frequency) overvoltage transients. These overvoltage signals may be quite large (i.e., ten times or more of the system voltage) and superimposed on the system voltage signal (voltage), so that they may appear or be concentrated at different phase angles of the system voltage signal. Some causes of these disturbances may include lightning, solar activity, switching within the electrical system, sudden load changes, etc.

[0020] Before continuing, it is important to note that terms such as "overvoltage," "overvoltage transient," "transient overvoltage," etc. refer to an event or signal where the voltage is greater than the expected voltage of the system voltage signal 104 at that particular instant. An overvoltage event may include a voltage transient that does not exceed the maximum voltage of the system voltage signal 104 if the transient event occurs during a low voltage portion of the system voltage signal 104. It is also important to note that the frequency of transient events is generally higher than the system frequency.

[0021] Figure 1A detection system 102 is shown, which is connected to a system or device to receive a system voltage signal 104 (i.e., a system transient voltage signal), and then monitors the system voltage signal 104 for transient overvoltage events. Generally, the system voltage signal 104 has a system voltage and a system frequency (e.g., 60 Hz), and any transient overvoltage event has a higher voltage and a higher frequency than the system voltage and the system frequency. The system may include a transformer, a generator, a high-voltage transmission line, a low-voltage transmission line, or an input or output of any other electrical device or system susceptible to transient voltages.

[0022] The detection system 102 includes an analog circuit 106 and a digital circuit 108, which cooperate with each other to detect and analyze transient overvoltage events. The analog circuit 106 includes a high-pass filter 110, an analog amplifier 112 for increasing input impedance, and a switch 114, which operate to hold transient analog signals generated during transient overvoltage events and then pass these transient analog signals to the digital circuit 108 for analysis and storage. The high-pass filter 110 receives an analog system voltage signal 104 (e.g., system voltage) and filters out any portion of the system voltage signal 104 that is below a predetermined frequency. In most configurations, the high-pass filter 110 is arranged to filter out any portion of the system voltage signal 104 that is at or below the system frequency (e.g., 60 Hz). Therefore, the high-pass filter 110 only passes high-frequency signals as a filtered signal 124 to the rest of the analog circuit 106. It should be noted that the term "high frequency" used herein refers to any frequency higher than the system frequency. Therefore, in an example system operating at a system frequency of 60 Hz, any signal greater than 60 Hz will be considered a high-frequency signal.

[0023] The filtered signal 124 is a transient voltage signal, which is transmitted to the analog amplifier 112 with a high input impedance for a sample-and-hold operation. Therefore, the operation of the analog amplifier 112 generates and outputs a held analog signal 126, which is transmitted to the digital circuit 108.

[0024] Switch 114 is a normally open switch that shorts out the simulated hold signal 124 when closed and operates to “reset” the analog circuit 106 to enable the analog circuit 106 to detect another transient overvoltage event.

[0025] The digital circuit 108 includes an analog-to-digital converter 116 and a microprocessor 118 or other computer system that receives and analyzes the retained analog signal 126 provided by the analog circuit 106. The analog-to-digital converter 116 receives the retained analog signal 126 and digitizes the signal to produce an output including a digital transient voltage signal 128. The microprocessor 118 analyzes the digital transient voltage signal 128 to determine the overvoltage level and the number of times similar overvoltage events have occurred. The data can be stored in a data storage device 122, and / or the data can be output to a monitor or other output device for display to a user. The microprocessor 118 also includes a controller 120 or performs the functions of a controller 120 to send a signal to the switch 114 to close it, thereby resetting the analog circuit 106 to detect another event. Therefore, each time the microprocessor 118 records, records, displays, or otherwise determines that an event has occurred and is measured, the controller 120 resets the analog circuit 106 to detect the next event. The reset process should be very fast (eg, 10 milliseconds or less) to reduce the possibility of missing events in rapid succession.

[0026] Continue to refer Figure 1 It should be noted that the microprocessor 118 or other computer device may use other output mechanisms to output data, including MODBUS, USB, wireless or cellular transmission, wired output, etc.

[0027] Figure 2 An alternative detection system 202 is shown, which includes an analog circuit 204 that receives the system voltage signal 104, as described with respect to FIG. Figure 1 The signal is processed as described above, and then the retained analog signal 126 is output. The detection system 202 also includes a digital circuit 206, which receives the retained analog signal 126 and performs the Figure 1 The analysis and storage process described.

[0028] Figure 2 The analog circuit 204 of the detection system 202 also includes a low pass filter 208, which receives the system voltage signal 104 from the system. The low pass filter 208 is arranged to pass only signals with frequencies below a predetermined threshold. In this arrangement, the threshold frequency is selected to allow the system frequency to pass. For example, if the system operates at a frequency of 60 Hz, the low pass filter 208 will be selected to filter any frequency above 60 Hz, thereby allowing the filtered system voltage signal 212 to pass through the low pass filter 208.

[0029] Figure 2The digital circuit 206 of the detection system 202 also includes a second analog-to-digital converter 210 that receives the filtered system voltage signal 212 and converts it into a digital system voltage signal 214. The digital system voltage signal 214 is then transmitted to the microprocessor 118 or other computer device for use. Specifically, the microprocessor 118 can use the digital system voltage signal 214 to determine the time or location of the detected transient event on the system voltage signal 104. Therefore, the level of overvoltage, the number of similar events, and the time (or phase angle) when these events occurred during the system voltage signal 104 can be detected.

[0030] It should be noted that other configurations may eliminate the high pass filter 110 or may include a switch (not shown) that disables the high pass filter 110. In configurations that include a switch, the switch is in one of two positions. In the first position, the high pass filter 110 is in the Figure 1 and Figure 2 10 is connected as shown. In the second position, the switch connects a bypass path that allows the system voltage signal 104 to completely bypass the high pass filter 110. In the absence of the high pass filter 110, the system is arranged to detect voltages greater than a predetermined value. Although any value can be selected, the predetermined value should be greater than the maximum system voltage. A system that bypasses the high pass filter 110 or does not include the high pass filter 110 will still detect many overvoltage events, but will not detect overvoltage events that occur at points in the cycle where the system voltage is low and the overvoltage is less than the maximum system voltage.

[0031] Figure 3 A flowchart showing the overall operation of the overvoltage monitoring system 302 is included. Figure 1 The detection system 102, IoT (Internet of Things) system 304 and cloud 306 or other data storage system accessible to users, customers 338, etc.

[0032] The process is initiated after an event is detected 308. The data associated with the detected event is analyzed to determine the number of peaks for each phase 310 and a step 312 of setting a MODBUS flag is performed, which indicates that an event was detected. Next, the peak data passes through a classification step 314 in which the data is classified according to its magnitude. In some configurations, the peaks are classified according to their actual voltage, while other configurations may classify the voltage relative to the system voltage (e.g., 200% of the system voltage). In most systems, the peaks are classified into groups or ranges. For example, one configuration (such as Figure 4 The peak value is classified into a percentage of the system voltage as shown in Figure 4In the embodiment, the range extends from 100% to 650% in increments of 20%, 30% and 50%. Of course, other ranges and increments may be used as needed or desired.

[0033] Continue to refer Figure 3 After the classification step 314, some systems may perform a phase angle determination step 318 in which the actual phase angle of the system voltage signal 104 when the voltage peak is detected is determined. This additional data may be used to detect patterns between the phase angle of the system voltage signal 104 and overvoltage events, such as Figure 6 shown.

[0034] After the classification step 314 or the phase angle determination step 318 (in systems that include this step), the data passes to a counting step 320 where the number of peaks in each classification of events is counted. As part of a store count step 316, the count data is passed to a MODBUS register to ensure that the data is stored. Upon receiving confirmation that the data has been correctly stored, a data retrieval flag 322 is set to allow a reset step 324 to reset the peak detection flag set in step 312.

[0035] The IoT system 304 acts as an interface between the detection system 102 and the cloud 306 or other data storage system associated with the overvoltage monitoring system 302. The IoT system 304 reads the peak detection flag from the MODBUS in step 326 and checks whether a timestamp is included in step 328. If there is no timestamp, the event is ignored as indicated in step 330. If there is a timestamp, the IoT system 304 reads the MODBUS register to retrieve the data from the storage count step 316 and switches the data retrieval flag 322 to "yes" to allow the detection system 102 to be reset. The data is then stored in a storage step 334. The data can be stored in a long-term storage system, or it can be stored in a short-term storage that is retrieved and moved regularly. For example, the data can be stored in a 24-hour cycle and moved every day. Finally, the data is transmitted to the cloud 306 or other storage system in a transmission step 336.

[0036] Figure 44 is an example of a possible display scheme for data collected by the detection system 102 and the overvoltage monitoring system 302. The display includes a histogram 406, which is divided into a plurality of categories 410, each of which represents an overvoltage range. In the example shown, the first category 410 includes a count of overvoltage events between 100% and 120% of the system voltage. The second category 410 includes a count of overvoltage events between 120% and 150% of the system voltage. The remaining categories 410 include a count of overvoltage events across 50% of the system voltage and within a range extending between 150% and 650% of the system voltage. The category range 408 is set on the right to give the user an indication of the actual voltage value of each category 410.

[0037] To enhance the histogram 406, a time filter 402 and a phase filter 404 are provided. The time filter 402 allows the user to select one of several predefined time windows to present the data, and includes a custom selection that allows the user to select a custom date or time range. The phase filter 404 allows the user to view data for any one of the available phases of the system voltage signal 104 (if it is a multi-phase signal) or view all phases together.

[0038] Figure 4 The display scheme includes multiple displays with various icons that can be used to select Figure 4 Histogram 406 is shown. Figure 5 An overvoltage icon 502 is shown that may be used in this listing of icons to direct the user to the desired histogram 406 .

[0039] Figure 6 Shown in use Figure 2 Another possible display that may be produced when the detection system 202 detects events including voltage spikes and also detects when the voltage spikes occur relative to the system voltage signal 104 . Figure 6 The display includes a Y-axis that is divided into different category ranges 408. The X-axis represents the phase angle of the system voltage signal 104 plotted relative to the second Y-axis. Each circular element represents a category 410 of an overvoltage peak, and the size of the circle represents the number of events within the range at a specific phase angle of the system voltage signal 104. Thus, the first of the circles 602 represents the number of peaks that occurred between Pi / 2 and Pi relative to the system voltage signal 104 in range 7.

[0040] Although the exemplary embodiments of the present disclosure have been described in detail, those skilled in the art will understand that they may make various changes, substitutions, variations, and improvements as disclosed herein without departing from the spirit and scope of the present disclosure in its broadest form.

[0041] Nothing in this application should be construed as implying that any particular element, step, act, or function is essential to be included in the claims: the scope of the claimed subject matter is limited only by the allowed claims. Furthermore, unless the exact phrase "means for" is followed by a participle, the claims are not intended to invoke a means plus function claim construction.

Claims

1. A detection system for detecting transient overvoltage events in an electrical system operating at a system frequency, the detection system comprising: an analog circuit connected to the electrical system and comprising a high pass filter operable to allow passage of transient voltage signals having a signal frequency higher than the system frequency; a digital circuit comprising an analog-to-digital converter and a microprocessor, the analog-to-digital converter operative to convert the transient voltage signal into a digital transient voltage signal, the microprocessor operative to receive the digital transient voltage signal, direct the digital transient voltage signal to a data storage device for storage in an overvoltage database, and reset the analog circuit; as well as A computer system is operable to output data stored in the overvoltage database.

2. The detection system according to claim 1, wherein: The analog circuit also includes an analog amplifier that receives the transient voltage signal and holds the transient voltage signal for a period of time that exceeds a duration of the transient overvoltage event.

3. The detection system according to claim 1 further comprises a switch arranged to generate a short circuit in the analog circuit to reset the analog circuit, the switch being movable between an open position and a closed position by the microprocessor. 4 . The detection system of claim 1 , further comprising a low pass filter operable to allow a system voltage signal at the system frequency to pass therethrough. 5 . The detection system of claim 4 , further comprising a second analog-to-digital converter operable to convert the system voltage signal into a digital system voltage signal.

6. The detection system according to claim 5, wherein: The microprocessor receives the digital system voltage signal to determine a phase angle of the system voltage signal when the transient voltage signal is generated.

7. The detection system according to claim 1, wherein: The electrical system is a three-phase electrical system, and wherein the analog circuit and the digital circuit are connected to a first phase of the electrical system, and wherein the detection system further comprises a second analog circuit and a second digital circuit connected to the second phase and a third analog circuit and a third digital circuit connected to the third phase.

8. A detection system for detecting transient overvoltage events in an electrical system operating at a system frequency, the detection system comprising: a simulation circuit connected to the electrical system and comprising: a high pass filter operable to allow a transient voltage signal having a signal frequency higher than the system frequency to pass; and a low pass filter operable to allow a system voltage signal at the system frequency to pass therethrough; A digital circuit, the digital circuit comprising: an analog-to-digital converter operative to convert the transient voltage signal into a digital transient voltage signal and to convert the system voltage signal into a digital system voltage signal; and a microprocessor operable to receive the digital transient voltage signal and the digital system voltage signal and to compare the digital transient voltage signal and the digital system voltage signal to determine a phase angle of the system voltage signal when the transient voltage signal was generated, the microprocessor further operable to determine an overvoltage value, direct the overvoltage value and associated phase angle to a data storage device for storage in an overvoltage database, and reset the analog circuit; and A computer system is operable to output data stored in the overvoltage database.

9. The detection system according to claim 8, wherein: The analog circuit also includes an analog amplifier that receives the transient voltage signal and holds the transient voltage signal for a period of time that exceeds a duration of the transient overvoltage event.

10. The detection system of claim 8, further comprising a switch arranged to generate a short circuit in the analog circuit to reset the analog circuit, the switch being movable between an open position and a closed position by the microprocessor. 11 . The detection system of claim 8 , further comprising a second analog-to-digital converter operable to convert the system voltage signal into the digital system voltage signal.

12. The detection system according to claim 8, wherein: The electrical system is a three-phase electrical system, and wherein the analog circuit and the digital circuit are connected to a first phase of the electrical system, and wherein the detection system further comprises a second analog circuit and a second digital circuit connected to the second phase and a third analog circuit and a third digital circuit connected to the third phase.

13. A method of detecting a transient overvoltage event in an electrical system operating at a system frequency, the method comprising: passing a signal from the electrical system to an analog circuit; Filtering the signal to allow a first transient voltage signal having a signal frequency higher than the system frequency to pass; amplifying the first transient voltage signal; converting the first transient voltage signal into a digital transient voltage signal in a digital circuit; determining an overvoltage value of the digital transient voltage signal; storing an overvoltage value of the digital transient voltage signal; as well as The analog circuit is reset to allow the analog circuit to detect a second transient voltage signal.

14. The method according to claim 13, further comprising: The signal is filtered to generate a system voltage signal having the system frequency, and the system voltage signal is converted into a digital system voltage signal.

15. The method according to claim 14, further comprising: A phase angle of the system voltage signal when the transient voltage signal is generated is determined.

16. The method according to claim 13, wherein: The resetting step includes moving the switch between an open position and a closed position.

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