RU2022312C1 - Nonlinear correcting unit - Google Patents

Abstract

FIELD: automatic control systems. SUBSTANCE: unit has amplifier 1, module determining unit 2, two algebraic adders 3 and 4, scaling unit 5, two-pole and single-pole peak detectors 6 and 10 correspondingly, adder 11, two pulse formers 7 and 12, null detector 8, controlled switch 9, OR gate 13. EFFECT: improved precision. 3 dwg

Description

 The invention relates to automatic control and is intended to improve the dynamic characteristics of automatic control systems.

 Known non-linear corrective device consisting of a storage element, a linear inertialess block, a comparison element, a relay element, a multiplication unit, a module determination unit, a filter and a zero-organ [1].

 The disadvantage of this device is the dependence of the phase detection introduced into the system on the frequency of the input signal.

 A nonlinear correcting device is also known, consisting of an amplifier, a module determination unit, a multiplication unit, a peak detector, a scaling unit, an adder, a signal relay and a zero-organ [2].

 The disadvantage of this device is the high nonlinearity of the equivalent phase characteristic, limiting the scope of the correction device.

 The closest in technical essence to the proposed one is a nonlinear correction device containing an amplifier, a module definition unit, first and second algebraic adders, a scaling unit, a bipolar peak detector, a shaper, a zero-organ, and a controlled key [3].

 The input harmonic signal is amplified to the required level by an amplifier and fed to the summing input of the second adder. The signal from the output of the scaling unit, which changes the value of the output signal of the bipolar peak detector (0 <m <1), representing the amplitude value of the input signal for the current sign-constant interval, is fed to the subtracting input of the second adder via a controlled key. The key is controlled by the driver in accordance with the absolute value of the difference between the amplitude and current values of the input signal of the device. The output of the device is the output of the second adder. The characteristics of the device are determined by the transfer coefficient of the scaling unit.

 The disadvantage of this device is the low accuracy in the case when the magnitude of the transfer coefficient of the scaling unit differs from the nominal.

 The purpose of the invention is improving the accuracy of the correction device.

 This is achieved by introducing into the device containing an adder, the summing input of which is connected to the input of the device through an amplifier, and subtracting through a series-connected bipolar peak detector, a first adder, a module determination unit, a driver and a controlled key, and the second input of the bipolar peak detector is directly connected to subtracting the input of the first adder, the input of the device and the input of the zero-organ, the output of which is connected to the second input of the bipolar peak detector, the output of which is connected n with a summing input of the first adder and an input of a scaling unit connected by an output to the second input of the controlled key, a unipolar peak detector, an adder, a pulse shaper and an OR element connected in series, the subtracting input of an additional adder connected to the output of the module definition unit and the first input of the unipolar peak detector the second input of which is connected to the second input of the bipolar peak detector and the output of the OR element, the first input of which is connected to the zero-op output Ghana, and the second with the release of an additional shaper.

 A new circuit of elements generates an output pulse of the peak detectors at the output of the element OR in the case when the difference between the current and maximum module value of the difference of the input signal and its peak value (output of the module definition unit) is nonzero (signal at the output of the third adder), or when passing signal at the input of the device through zero (zero-organ output).

 In FIG. 1 shows a block diagram of a proposed correction device; in FIG. 2 is a diagram explaining the operation of the device; in FIG. 3 is a block diagram of a bipolar peak detector.

 The nonlinear correction device includes an amplifier 1, a module determination unit 2, first and second algebraic adders 3 and 4, a scaling unit 5, a bipolar peak detector 6, a first driver 7, a zero-organ 8, a controlled key 9, a unipolar peak detector 10 , the third adder 11, the second shaper 12 and the OR element 13. The output of the first adder 3 is the output of the device, its summing input is connected to the input of the device through the amplifier 1, and the subtracting input is connected through the bipolar peak detector in series OR 6, an adder 4, a module determination unit 2, the first generator 7 and the controllable switch 9. subtracting input of the adder 4 is connected to the input of the zero-member 8 and the input devices directly. The second input of the controlled key 9 through the scaling unit 5 is connected to the output of the bipolar peak detector 6, the installation input of which is connected to the installation input of the unipolar peak detector 10 and the output of the OR element 13, the first input of which is connected to the output of the zero-organ 8, and the second to the output the shaper 12, controlled by the adder 11. The inputs of the adder 11 are connected to the output of the module determination unit 2, summing through the peak detector 10, and subtracting directly.

 The bipolar peak detector 6 is implemented based on peak detectors of positive values 14, negative values 15 having a common reset circuit, and an adder 16 connected in accordance with the circuit of FIG. 3. The inputs of the peak detectors of positive 14 and negative 15 values are connected and are the input of the bipolar peak detector 6, the output of the adder 16, to the inputs of which the outputs of the peak detectors 14 and 15 are connected, is the output of the bipolar peak detector 6.

The output signal of the bipolar peak detector 6 is the maximum value of the input signal for the current sign-constant interval. The signal converted by the scaling unit 5 (0 <m <1, if k is the transfer coefficient of unit 1 is equal to unity), the signal is supplied to the second input of the managed key 9, the operating mode of which is set by the driver 7 in accordance with the output of the module definition unit 2, which in turn is determined the difference between the maximum and current values of the input signal of the device. When the input signal of the device increases, its maximum and current values coincide, at the output of the adder 4, zero is maintained, the controlled key 9 is open. After the input signal of the device reaches its maximum value and begins to decline, the difference at the output of the adder 4 increases, which entails the closure of the key 9, and the output value of the device decreases by ε _m ˙ m. The absolute value of the difference between the current and amplitude values of the input signal of the device is compared using the adder 11 with the maximum value of the same difference — the output of the peak detector 10 so that with a monotonous input signal of the device at the output of the shaper 12 is maintained zero. The process continues until the direction of change of the input value of the device changes - the absolute value of the difference at the output of the module definition block 2 decreases, this provides a non-zero signal at the output of the adder 11 and entails the reset of the peak detectors 6 and 10 from the shaper 12 through the OR element 13. When the input signal of the device passes through zero, peak detectors from the OR 13 element are also reset, but due to the signal from the zero-organ 8, this ensures the operability of the device for any changes in the input Ignala. Next, the processes are repeated.

.Consider the operation of the corrective device on the phase plane (Fig. 2) on the example of a second-order system with a transfer function
W (p) =

.

Let the ratio 4KT> 1 be true for the initial system, in this case the phase trajectory has the form of a twisting spiral. The initial conditions are specified on the plane by point N. If the magnitude of the transfer coefficient of the scaling unit 5 m is less than the nominal, the movement occurs along curve 17 (Fig. 2), the signal at the output of adder 4 is zero, at point A, when changing the sign of speed, the current and maximum values of the input the signal (the output of adder 4) is different, and according to the signal of the driver 7, the controlled key 9 closes - the vertical axis in the phase portrait of the system jumps abruptly by the value of m ε _m1 to position I, the movement proceeds along curve 18. Until the trajectory hits point B, the value The difference between the current and maximum values of the input signal (adder 4) increases and zero is maintained at the output of adder 10. When hit point B, the absolute maximum and current values of the difference become different and the peak detectors 6 and 11 are reset according to the signal of the shaper 8. The peak detector 6 stores the new amplitude value of the input signal, and the vertical axis jumps to position II, and the movement continues along the path 19. This allows you to eliminate the constant component of the error in the system.

 Thus, the introduction of an additional control circuit can significantly increase the accuracy while providing an aperiodic transient in the original system.

Claims (1)

 A NONLINEAR CORRECTIVE DEVICE containing an amplifier, the input of which is the input of the device and connected to the input of the zero organ, subtracting the input of the first algebraic adder and the information input of the bipolar peak detector, the output of which is connected to the input of the scaling unit and the summing input of the first algebraic adder, the output of which connected in series by the module definition unit and the first driver, the output of which is connected to the control input of the managed key, inf the irrational input of which is connected to the output of the masturbation unit, the output - with the subtracting input of the second algebraic adder, the summing input of which is connected to the output of the amplifier, and the output is the output of the device, characterized in that, in order to improve the accuracy of the device, unipolar peak connected in series a detector, a third algebraic adder, a second driver and an OR element, the second input of which is connected to the output of the zero-organ, the output to the discharge inputs of the peak detectors, and the output is block determining module connected to the input of the unipolar peak detector and a subtraction input of the third algebraic adder.

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