solialpine.blogg.se - Lightning score calculator

On July 17, 2022, at Heinz Nixdorf MuseumsForum in Paderborn city of Germany, 12-year-old Indian mental calculator Aaryan Nitin Shukla clinched the title to become the new World Champion. The world's best mental calculators are invited every two years to compete for the Mental Calculation World Cup. Leonhard Euler was a prominent mental calculator.Ī mental calculator or human calculator is a person with a prodigious ability in some area of mental calculation (such as adding, subtracting, multiplying or dividing large numbers). ( August 2011) ( Learn how and when to remove this template message) Please help to improve this article by introducing more precise citations. The digital recorder is used to calculate and obtain low measuring uncertainty.This article includes a list of general references, but it lacks sufficient corresponding inline citations. The new definition is more accurate and is based on digital record. The mutation of test voltage factor in 97 version and the randomness of average curve cause high uncertainty. Determine time parameter of basic curve taking U as peak voltage.Calculation of relative overshoot amplitude.Determine the peak U of datum curve U (t)Ĭalculate overshoot duration t, that is, the time interval of two inter-points of U(t) curve and U (t) curve at both sides of U(t) maximum and calculate overshoot frequency f=1/2t.Determine the datum curve based on the record curve.So the mutation occurs (which is shown in Fig 1).Īccording to actual test data shown in Fig 4, calculate via new procedures and method: Maximum amplitude of the curve, also known as the peak, is defined as test voltage value". "If the oscillation frequency is no less than 0.5MHz or overshoot time is no higher than 1μs, a average curve should be drawn to facilitate the measurement. (3) When the overshoot frequency is close to 500kHz, the mutation from the maximum value to the maximum value of average curve will cause great error. So, test personnel have to subjectively determine whether the drawn smooth curve is correct. The actual measure is to draw a "average curve" at the oscillation for lightning impulse full-wave voltage with damped oscillation to solve the parameters. Hence, test personnel had no choice but to read the waveform and decide the time when this impulse can be handled as the lightning impulse full-wave voltage with damped oscillation based on their own experience. In addition, It was hard to set the limit standard of oscilloscope resolution due to actual condition restriction. It took much time to read the oscillogram. In addition, the comparison to smooth impulse will lead to great uncertainties during the parameter estimation.Īt that point, most labs utilized the oscilloscopes to record impulse waveform. The average curve can be selected at will, which brings about great uncertainties for calculating lightning impulse full-wave parameters with damped oscillation.

In fact, all the impulse bears the oscillation.

The lightning impulse full-wave waveform is divided into two categories: smooth lightning impulse full-wave voltage and lightning impulse full-wave voltage with damped oscillation.

The overshoot is defined as per oscillation peak exceeding test voltage peak extent. Maximum amplitude of the curve, also known as the peak, is defined as test voltage value Īs for smooth lightning impulse wave, it is believed that the overshoot does not exist while if the oscillation frequency is higher than 0.5MHz, the overshoot exists. If the oscillation frequency is no less than 0.5MHz or overshoot time is no higher than 1μs, a average curve should be drawn to facilitate the measurement. As for some test circuit, oscillation overshoot may occur at the impulse peak. As for smooth lightning impulse wave, the test voltage is peak Combing with actual examples, the difference between both is compared and analyzed in this paper.Īccording to GB/T 16927.1-1997, relevant information about lightning impulse test of high voltage product and voltage waveform of standard lightning impulse is as follows: IEC 60060-1 latest revised version redefines the overshoot of lightning impulse and its calculation method. Regulations in the original version are not been suitable for such high voltage, especially lightning impulse. With years of development and application of 800kV and 1100kV equipment, test voltage has reached power frequency 1200kV, switching impulse 1950kV and lightning impulse 2700kV. During that period, the electric power equipments have rapidly developed, especially in China. It has been more than 10 years since the current version GB/T16927.1 was issued and enforced in 1997.