SU613266A1 - Phase meter - Google Patents

Description

The invention relates to the field of phase-measuring technology and is intended to measure the phase difference of sinusoidal voltages. Known phase meters for measuring the phase difference of sinusoidal voltages contain a phase-shifting circuit –y, correlators, a reference voltage generator, and a tg determination unit at 1. For such a meter, in a wide frequency range, it is necessary to create a wideband splitting of the input signals into –– but practically such phase lines The detectors are operational only at a fixed frequency and a slight deviation of the lacTOTbi signal from the specified value of npHiBO gives a large measurement error. This factor limits the frequency range of known meters and reduces their applicability. The closest to the technical essence of the present invention is a phase meter containing two phase detectors, a 90 ° phase shifter, two amplifiers and an electron-beam indicator 2. The disadvantages of this phase meter are the small frequency range limited by almost one fixed frequency, which is caused by the difficulties of obtaining phase in a wide range of frequencies. The purpose of the invention is to expand the frequency range of measurements of the phase difference of sinusoidal voltages. To do this, a phase detector containing two phase detectors, the first inputs of which are connected to the first input bus of the phase meter, and the second input of the first phase detector is connected to the second input bus of the phase meter, two amplifiers, the outputs of which are connected to an electron-beam indicator, have two peak detectors, a frequency multiplier of four, a short pulse shaper and a pulse selector, the second input of the second phase detector connected to the second input bus of the phase meter and to the input of the frequency multiplier four, the output of which through the shaper of short pulses connected to the input of the pulse selector, the outputs of which are connected to the control inputs of the phase and output of the detectors, and the outputs of the detectors through the peak detectors connected to the inputs of the amplifiers. This eliminates the need to create a wideband input signal split. The drawing shows a structural diagram of the phase meter. The phase meter contains a multiplier / frequency of four connected to the input of the phase meter and connected in series with the shaper 2 short IM pulses and a selector of 3 pulses, which is one of the output switches to the control input of the phase detector 4, and the second to the control input of the phase detector 5 , the measuring inputs of the phase detectors are connected to the phase meter outputs, the output voltage of the phase detectors is processed by the peak detectors 6 c 7 and is fed respectively to the amplifiers 8, 9, the output voltage of which is received t on the deflector plates of the indicator 10.

The device works as follows.

For a narrowband signal, the phase shift of the harmonic components is

practically corresponds to the half-wave offset of the signal by a quarter of the high-frequency oscillation period. Therefore, instead of the broadband raster: clinging the input signal to -.j-, you can

take paired readings of the instantaneous values of the phase oases, shifted by a quarter of the period: zyso-frequency oscillations.

When serving on Bx. 2 reference voltages This voltage is processed by a frequency multiplier / and fed to a short pulse shaper 2, at the output of which short impulses are formed, corresponding to a zero transition of the output multiplier. The period of the output impulses of a formator with a duration of / a. Corresponds to a period of frequency 4 / (/;.- cha: output signal current). P pulses from the output of the driver short pulses are fed to the input of the selector 3, on one of the outputs of which are received even pulses; on the other - odd. Thus, at the output of the pulse selector, pc-counted pulses are formed, which correspond to Dee;} iodine of the input oscillation.

The output even pulses of the selector are fed to the phase detector 4, and the odd ones - to the phase detector 5. Phase detectors 4 and 5 measure the measured phase difference of the voltages acting on Bx. 1 and IN. 2 only at the moment of impacting the detectors:; selectable pulses of the selector, the duration of the count, and shifted relative to each other by / 4 periods. The pulses from the output of the phase detectors, which sand the information about the phase difference of the measured signals, are stretched in time with the help of peak detectors 5 and 7.

1 thus, the output voltage of peak detectors b and 7, respectively, is

,., .. 0 5 L181Psr (/ „)

n 1 yBb, A, COS- (t,),

"| |

where: ф - measured phase shift;

k and / «2 - coefficients: transformations;

n is the number of counts;

L 1 1 t / 2; LE Y2 i (2; and Hz - amplitudes of input voltages.

The voltages from the outputs of the peak detectors, after amplification in amplifiers 5 and 5, receive deflection fields: an indicator 10, for which there is a very low indication of the measured phase difference in the polar coordinate system.

Tests of this phase meter showed the possibility of obtaining (the overlap coefficient of the frequency range up to 1000 without retooling and adjusting the circuit.

Claims (2)

1. Pestrikov V.Ye. Phase radio engineering systems. M., “Owls. radio, 1968. 2. Belavin O.V., Weizel V.A., Ulnov V.S. Shortwave radio direction finders. M., “Oborongiz, 1959.