RU206074U1 - 90 DEGREES PHASE SHIFT DEVICE - Google Patents

Abstract

The utility model relates to electrical measuring equipment and can be used in various radio engineering devices using quadrature splitting of a sinusoidal signal, as well as in reactive electrical energy meters. The device contains an integrator, first and second amplitude detectors, a division unit, an analog multiplier and an inverter, and the input of the device is connected to the inputs of the integrator and the first amplitude detector, the integrator output is connected to the first input of the division unit and the input of the second amplitude detector, the output of which is connected to the second input division unit, the output of which is connected to the first input of the analog multiplier, the second input of which is connected to the output of the first amplitude detector, and the output of the analog multiplier through the inverter is connected to the output of the device. The technical result of the claimed utility model is to improve the accuracy of the device. 2 ill.

Description

The utility model relates to electrical measuring equipment and can be used in various radio engineering devices using quadrature splitting of a sinusoidal signal, as well as in reactive electrical energy meters.

Known device for phase shift by 90 ° [USSR author's certificate No. 1511705 IPC G01R 25/04, G01R 25/00, publ. 09/30/1989], containing a phase-shifting element, a phase detector, an integrator, a controlled voltage divider and an adder, and the input of the integrator is connected to the output of the phase detector, one of the inputs of which is connected to the input of the phase-shifting element, which is the input of the device, the output of the adder is the output of the device and is connected to the second input of the phase detector, and the inputs of the adder - respectively with the outputs of the phase-shifting element and the controlled voltage divider, and the control input - with the output of the integrator.

The disadvantage of this device is its low accuracy, due to the fact that it does not provide equality of the amplitudes of the input and output voltages in a wide frequency range.

The closest analogue to the proposed utility model is a 90 ° phase shift device [Patent for PM No. 168700 RF, IPC G01R 25/04, publ. 02/15/2017], containing an integrator, an adder, an amplifier with a controlled gain, the first and second amplitude detectors and a PI controller, and the adder is made differential, and the input of the device is connected to the input of the first amplitude detector and the input of the integrator, the output of which is connected to the input of the amplifier with a controlled gain, the output of which is connected to the input of the second amplitude detector and is the output of the device, and the outputs of the first and second amplitude detectors are connected, respectively, to the non-inverting and inverting inputs of the adder, the output of which is connected through a PI controller to the control input of the amplifier with a controlled gain gain.

This technical solution was chosen as a prototype.

This device in the steady state provides equality of the amplitudes of the input and output voltages in a wide frequency range. However, the presence of a PI controller in the device leads to a decrease in its response rate in transient modes, and hence to a loss of accuracy. This is due to the presence of a certain time of the transient process when the PI controller processes the error signal in transient modes, due to the presence of the integral component of the transmission coefficient in the controller.

The technical result of the claimed utility model is to improve the accuracy of the device.

The specified technical result is achieved by the fact that a division unit, an analog multiplier and an inverter are additionally introduced into the known 90 ° phase shift device containing an integrator, first and second amplitude detectors, the input of the device being connected to the inputs of the integrator and the first amplitude detector, and the integrator output connected to the first input of the division unit and the input of the second amplitude detector, the output of which is connected to the second input of the division unit, the output of which is connected to the first input of the analog multiplier, the second input of which is connected to the output of the first amplitude detector, and the output of the analog multiplier through the inverter is connected to the output of the device ...

Significant differences of the proposed device are the introduction of a division unit, an analog multiplier and an inverter and the organization of new connections between the elements of the device. The combination of elements and connections between them provide a positive effect - increasing the accuracy of the device.

The essence of the utility model is illustrated by drawings. FIG. 1 shows a functional diagram of the device, FIG. 2 - timing diagrams of voltages u _in , u ₁ -u ₃ , u _out .

The converter (Fig. 1) contains an integrator 1, a division unit 2, an analog multiplier 3, two amplitude detectors 4,5 and an inverter 6.

The converter works as follows. The input sinusoidal AC voltage u _in = U _{m in} sinωt is fed to the inputs of the integrator 1 and the amplitude detector 5. At the output of the integrator 1, a voltage u _{1 is formed} , shifted in phase relative to u _in by an angle of 90 ° towards the lagging side (Fig. 2):

where U _{m in} - the amplitude of the input voltage;

U _1m - the amplitude of the output voltage of the integrator;

ω is the circular frequency of the input voltage;

R is the resistance of the integrator resistor;

C is the capacitance of the integrator capacitor.

After dividing the output voltage of the integrator by its amplitude U _1m , formed by the amplitude detector 4, in the dividing unit 2, a voltage u ₂ = -cosωt with a unit amplitude is formed at its output, which is fed to the first input of the analog multiplier 3.

In the analog multiplier 3, the voltage u _{2 is} multiplied with the amplitude value of the input voltage U _{m in} , coming from the amplitude detector 5, as a result, a voltage u ₃ = -U _{m in} cosωt is formed at its output, thereby restoring the amplitude of the input voltage U _{m in} ...

After inversion by the inverter 6, at its output and at the output of the device, a voltage u _out = U _{m in} cosωt is generated, phase-shifted relative to u _in by an angle of 90 °.

Thus, in the proposed utility model, the elimination of the PI controller leads to an increase in the speed of the device in transient modes, thereby achieving the technical result - an increase in the accuracy of the converter.

In the practical implementation of the proposed device, the integrator 1 can be performed according to the well-known scheme on an operational amplifier (OA) with a timing RC circuit. Analog multiplier 3 can be performed on the KR525PS3 microcircuit. Division 2 can be performed on an op-amp by including a multiplier on the K525PS3 microcircuit in its negative feedback circuit. Amplitude detectors 4 and 5 can be made according to one of the well-known schemes (A. J. Peyton, V. Wolsh. Analog electronics on operational amplifiers. - M .: BINOM, 1994, p. 292, Fig. 11.17; p. 304, Fig. . 11.29). Inverter 6 is a conventional unity-gain op-amp inverting amplifier.

Claims (1)

A 90-degree phase shift device containing an integrator, first and second amplitude detectors, and the input of the device is connected to the inputs of the integrator and the first amplitude detector, characterized in that it additionally contains a division unit, an analog multiplier and an inverter, and the integrator output is connected to the first the input of the division unit and the input of the second amplitude detector, the output of which is connected to the second input of the division unit, the output of which is connected to the first input of the analog multiplier, the second input of which is connected to the output of the first amplitude detector, and the output of the analog multiplier through the inverter is connected to the output of the device.

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