Intelligent power network controller and working method thereof

Abstract

The invention relates to an intelligent power network controller comprising a program-controlled amplifier, a current sensor, and a central controlling unit. A current amplification signal output terminal of the program-controlled amplifier is connected to the central controlling unit. An inverse-time over-current protection curve is stored as a baseline in the central controlling unit. A time setting coefficient corresponding to the baseline is Tp0. A time setting coefficient corresponding to a circuit requiring testing is Tp1, wherein the current sensor is in the circuit. An amplification multiple of the program-controlled amplifier is controlled at the value of Tp0 / Tp1 by the central controlling unit. According to the volume of the current amplification signal outputted by the program-controlled amplifier, a corresponding protective action time limit T0 is retrieved on the baseline. An actual protective action time limit T1 is calculated according to a formula that Ti=(Tp1 / Tp0)T0. Finally, according to the actual protective action time limit T1, the central controlling unit executes a protection action through a driving circuit connected to the central controlling unit, such that the tested circuit with the current sensor is cut off.

Description

technical field [0001] The invention relates to a smart grid controller and a working method thereof. Background technique [0002] Various faults and abnormal operating states may occur in the power system during operation. The most common and dangerous faults are short circuits in various forms. Short-circuit faults can destroy the stability of the power system and cause the entire system to collapse, causing large-scale power outages and often causing greater losses to the national economy. Therefore, it is a technical requirement in this field to automatically, rapidly and selectively cut off the faulty line from the power system to ensure the normal operation of other non-faulty parts. [0003] In the prior art, by sampling the load overcurrent and figure 1 The curve family of the current-time characteristic curve shown, obtains the protection action time limit of the grid controller. When the load overcurrent current is large, the time limit of the protection action...

AI Technical Summary

Problems solved by technology

[0005] In the existing smart grid controller, if the calculation is performed in the single-chip microcomputer according to the above mathematical model, since the calculation of the three-phase current needs to be performed, and there are root sign operations and division operations, the calculation amount is very large; if it is made into a table, the If the above-mentioned curves are discretized and stored in the ROM of the single-chip microcomputer, the amount of information will be very large, and the corresponding cost will be relatively high; therefore, how to solve the above-mentioned problems is a technical problem in the art

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