KR-102963019-B1 - SMART POWER PROTECTION SYSTEM WITH OFFSET TOLERANCE COMPENSATION

Abstract

The smart power protection system having an offset error compensation function according to the present invention comprises a power protection device that sets the ratio of the output voltage to the input voltage of a power converter as a reference ratio according to an initial state or setting, detects the input voltage and output voltage of the power converter to calculate the ratio of the output voltage to the input voltage of the power converter at a monitoring point as a current ratio, calculates the ratio of the current ratio to the reference ratio as an efficiency, and transmits it externally; and a server that generates an alarm signal by determining that an abnormality has occurred in the power converter when the efficiency received from the power protection device deviates from a reference range, wherein the server sets a reference efficiency value and a reference efficiency pattern of the power protection device according to an initial state or setting, compares a current efficiency pattern monitored for a certain period of time with a reference efficiency pattern, and if it is determined that the current efficiency pattern is similar to the reference efficiency pattern, determines whether the efficiency deviates from the reference range based on an efficiency value corrected by shifting it by an efficiency offset value calculated by comparing the current efficiency value and the reference efficiency value. According to the present invention as described above, it is possible to prevent the problem of misjudging a normal power converter as being in an abnormal state due to voltage offset caused by the attachment or detachment of a voltage sensor or temporary fluctuations in input voltage, and to accurately diagnose whether a fault exists.

Inventors

• 이수한

Assignees

• 주식회사 에스와이시스템

Dates

Publication Date

20260511

Application Date

20250611

Claims (5)

1. A power protection device that sets the ratio of the output voltage to the input voltage of a power converter as a reference ratio according to an initial state or setting, detects the input voltage and output voltage of the power converter to calculate the ratio of the output voltage to the input voltage of the power converter at the time of monitoring as a current ratio, calculates the ratio of the reference ratio to the current ratio as an efficiency, and transmits it externally; It includes a server that generates an alarm signal by determining that an abnormality has occurred in the power converter when the efficiency received from the power protection device deviates from a reference range, A smart power protection system having an offset error compensation function, characterized in that the server sets a reference efficiency value and a reference efficiency pattern of the power protection device according to an initial state or setting, and if the current efficiency pattern monitored for a certain period of time is determined to be similar to the reference efficiency pattern, the server determines whether the efficiency deviates from the reference range based on an efficiency value corrected by shifting by an efficiency offset value calculated by comparing the current efficiency value and the reference efficiency value.
2. A power protection device that detects the input and output voltages of a power converter and transmits them externally; A server that sets a reference input voltage pattern, a reference output voltage pattern, a reference ratio which is the ratio of the output voltage to the input voltage, and a reference efficiency pattern of a power converter according to an initial state or setting, calculates the ratio of the output voltage to the input voltage of the power converter as a current ratio, calculates the reference ratio relative to the current ratio as an efficiency, and generates an alarm signal by determining that an abnormality has occurred in the power converter if the efficiency deviates from a reference range. A smart power protection system having an offset error compensation function, characterized in that the server calculates an offset value for an input voltage or output voltage when it determines that an input voltage pattern or an output voltage pattern monitored for a certain period of time is similar to a reference input voltage pattern or a reference output voltage pattern, respectively, and calculates a corrected efficiency for a corrected input voltage or output voltage by reflecting the offset value.
3. In paragraph 1 or 2, A first power converter used as a main power supply and a second power converter used as an auxiliary power supply; Main switch supplying external power; First and second relay switches for interrupting the connection between the main switch and the first and second power converters; and It includes a controller that controls the operation of the first and second relays, and A smart power protection system having an offset error compensation function, characterized in that the above server generates a control signal to connect the main switch to the second power converter and transmits it to the controller when it is determined that the above efficiency is due to an abnormality in the power converter or that the lifespan of the power converter has ended.
4. In paragraph 1 or 2, A smart power protection system having an offset error compensation function characterized by generating an alarm signal when the above efficiency change pattern corresponds to a predetermined abnormal pattern.
5. In paragraph 1 or 2, Whether an abnormality has occurred in the above power converter is A smart power protection system having an offset error compensation function, characterized by being determined by applying at least one of the following rules: a first rule for determining whether the number of points where the efficiency approaches a first reference range according to a preset standard is greater than a certain number; a second rule for determining whether the number of points located between the first reference range and a second reference range lower than the first reference range is greater than a certain number within a certain time period; and a third rule for determining whether the change in the efficiency has periodicity greater than a certain amplitude.

Description

Smart Power Protection System with Offset Tolence Compensation The present invention relates to a smart power protection system having an offset error compensation function, and more specifically, to a technology that enables accurate diagnosis of abnormalities in a power converter by compensating for the offset error of a voltage sensing sensor that occurs intermittently when a voltage sensor is attached or detached for replacement or repair of a power converter or voltage sensor. As large buildings accommodate a large number of people, numerous energy-consuming devices are installed, and numerous power converters are installed to supply power to these energy-consuming devices. To reliably operate numerous energy-consuming devices, it is crucial to monitor the normal operation of power converters to detect failures and predict the likelihood of failure. Monitoring of power converters is typically performed by detecting the voltage at the output terminal of the power converter. For example, Korean Registered Patent No. 2074134 discloses a technology that monitors the voltage and current of the input or output terminal of a power converter and, if at least one of the voltage and current is in an abnormal state, transmits a command to stop operation to the power converter or transmits notification information to an administrator terminal. In addition, Korean Registered Patent No. 1634638 discloses a technology configured to install voltage sensors at an external power input terminal, an output terminal of a power supply unit, and an output terminal of a power distribution unit, respectively, to determine whether the amount of voltage change at each terminal exceeds a preset threshold value for a preset period of time. However, conventional monitoring technologies for power converters determine whether there is an abnormality by measuring only the voltage at the input or output terminals of the power converter. Consequently, if fluctuations in the input voltage occur or the voltage drops due to external shocks, the output voltage may deviate from the normal range. In such cases, a problem may arise where the power converter is misdiagnosed as having failed even though there is no actual abnormality. Meanwhile, when a voltage sensor is detached or reattached in a power converter for replacement or repair, an offset of a certain amount occurs in the voltage value detected by the sensor before and after the detachment, which may lead to a problem where the abnormality of the power converter cannot be accurately diagnosed. The occurrence of an offset here means that while the output pattern of the voltage sensor is substantially the same before and after the voltage sensor is attached, the output values before and after the voltage sensor are output in a form shifted by a certain amount along the y-axis. Therefore, it is necessary to develop technology capable of monitoring and diagnosing the operating status of the power converter by considering the offset occurring before and after the attachment and detachment of the voltage sensor. FIG. 1 is a configuration diagram of a smart power protection system having an offset error compensation function according to a first embodiment of the present invention. Figure 2 illustrates the screen configuration of the display unit of a power protection device. FIG. 3 is a graph illustrating an offset error compensation method according to a first embodiment of the present invention. FIG. 4 is a graph illustrating an input voltage offset correction method according to a second embodiment of the present invention. Figure 5 illustrates an example of a judgment rule for determining whether there is an abnormality in the efficiency change pattern. Figure 6 illustrates a power protection circuit using a backup power converter. The embodiments described in the present invention and the configurations illustrated in the drawings are merely preferred embodiments of the present invention and do not represent all of the technical concept of the present invention; therefore, the scope of the rights of the present invention should not be interpreted as being limited by the embodiments and drawings described in the text. That is, since the embodiments are subject to various modifications and may take various forms, the scope of the rights of the present invention should be understood to include equivalents capable of realizing the technical concept. Furthermore, the objectives or effects presented in the present invention do not imply that a specific embodiment must include all of them or only such effects; therefore, the scope of the rights of the present invention should not be understood as being limited by them. Unless otherwise defined, all terms used herein have the same meaning as generally understood by those skilled in the art to which this invention pertains. Terms defined in commonly used dictionaries should be interpreted as having meanings consistent with the context of the re