SU978064A1 - Periodic voltage harmonic phase and ampilutide analyzer - Google Patents

Description

(54)

ANALYZER OF THE AMPLITUDE AND PHASE OF HARMONIC PERIODIC STRESS

The invention relates to a radio measuring technique and can be used to measure the amplitude and phase of the harmonics of a periodic voltage in the study of nonlinear elements and devices.

A known analyzer of the amplitude and phase of periodic voltage harmonics, comprising a measuring channel and a switching voltage forming channel of this voltage 1.

However, such an analyzer with a high measurement accuracy works in a narrow range of analyzed frequencies due to the difficulty of obtaining harmonic quadrature voltages with the frequency of the measured harmonic in the frequency diagram.

There is a well-known amplitude-phase periodic voltage analyzer, which contains an input device, a linear amplifier, and electronic transducers. multipliers, indicators, quadrature signal generator, low-pass filters, C2 amplifiers,

The disadvantage of this analyzer is the narrow range of frequencies being analyzed due to the presence of frequency dependent circuits after the quadrature signal generator, which requires rebuilding when measuring different harmonics and frequencies, and their performance is also required, which causes technical difficulties in the manufacture of the analyzer.

The purpose of the invention is to expand the range of analyzed analyzer frequencies.

The goal is achieved

10 in that a known analyzer containing a serially connected input device and a linear amplifier, the first and second electron multipliers connected

15 with their first inputs to the output of the linear amplifier, indicators connected respectively to the outputs of the electronic multipliers, 20 serially connected clock pulses, a cross-feedback counter, a pulse driver and a large adder, the first output of which is connected to the second input of the first electron multiplier , and the second with BTOpfciM input of the second electron multiplier.

The drawing shows the structural electrical scheme of the proposed

thirty

analyzer.

The analyzer contains an input device 1, a linear amplifier 2, electron multipliers 3 and 4, indicators 5 and 6, a clock generator 7, a cross-feedback counter 8, a pulse driver 9, a scale adder 10

The analyzer works as follows.

The investigated input signal U / t / through the input device 1, the linear amplifier 2 is fed to the first inputs of the electronic multipliers 3 and 4. The second inputs of the electronic multipliers receive quadrature voltages with the frequency of the measured harmonic. The quadrature voltages are a stepwise approximation of the sinusoidal and cosine-like voltages obtained by summing 10 rectangular pulses with certain weights in a scale adder. Rectangular pulses have the same repetition period, but different duty cycle. These pulses are formed in the driver 9 from the output voltages of the counter 8 with cross-feedback. | In order to form quadrature voltages with the frequency of measured gammonics, it is necessary that the frequency w of clock pulses, fed to the counter 8 from the generator 7, is four times higher than the frequency of the generated voltage n, and taking into account the number of stages of approximation by a quarter of the period t, uJ - k TPN, where n is the number of the measured harmonic, and I is the frequency of the first harmonic. The number of approximation stages is selected from the condition of the permissible content of the harmonics in the generated voltage. The recalculation coefficient of the counter is 4 tons. Due to the input of the 7 clock pulse generator to the counter 8, the driver of the 9 pulses, the scale adder 10 in the analyzer provides wide-range quadrature voltages with the frequency of the measured harmonic with a given constant

in the whole working range of higher harmonic content.

The pulse clock sequence is automatically synchronized and synced to

reference voltage For this, the reference voltage with the frequency of the first harmonic is supplied to the synchronous input of the generator 7 clock pulses. Indicators 5 and b show the quadrature components of the measured harmonics.

Thus, the introduction of a clock generator, a cross-feedback meter, a pulse shaper, and a scale adder allows the analyzer to expand the range of analyzed frequencies.

Claims (2)

1. Authors certificate of the USSR 365658, -kl. G 01 R 23/16, 1972. 2. Authors certificate of the USSR 512434, cl. G 01 R 23/16, 1976. TO D -H P / | / | S I 1 J i t. eight