SU996992A1 - Discrete autoregulator for irrigation systems - Google Patents

Description

The invention relates to an automatic regulation technique and is intended to regulate the water level in irrigation canals of land reclamation systems with the help of multi-position electrically controlled gates of blocking hydraulic structures.

Discrete pulse-width autoregulators for reclamation systems are known, containing a yumming amplifier, an integrating amplifier and a relay unit, in which the output of the summing amplifier is connected to the input of the relay unit, and the output of the integrating amplifier is connected to the second input of the summed amplifier, moreover, for organizing the discrete pulse-width of the law of regulation, they also contain a stabilization unit, which is an RC time switch t 1

However, the known devices are characterized by low accuracy and reliability of operation and considerable adjustment time.

The closest in technical essence to the proposed auto-regulator is a discrete pulse-width auto-regulator for ameliorative systems, containing a summing amplifier, an inverting amplifier, the output of which is connected to the input of the amplifier with a capacitor and a discharge circuit of a relay unit with a dead zone and a relay amplifier, and allocation circuit module and time relay KS | 3 J.

ten

However, this auto regulator also has a low accuracy and reliability of operation and considerable adjustment time.

The low accuracy and reliability of the work of the well-known auto regulator is explained by the fact that the water level in the irrigation canals is subjected to wave oscillations, pulsations and bursts with a period reaching 20 seconds and amplitudes up to tens of centimeters. Under such conditions, in a known autoregulator, one is forced to set the value of the dead zone to be greater than the maximum value of the amplitude of the pulsations, i.e. significantly reduce the accuracy of the device, however, since the first input of the summed-up amplifier is given a pulsary switch signal,

30a at the second input - a linearly increasing voltage from the integrating amplifier, in a summing amplifier this signal is compensated not at the actual value of the error value, but at its minimum value in the period of the level oscillations, i.e. Immediately after turning on neither pulse. Thus, the well-known auto regulator cannot provide the accuracy and reliability of work required for the automation of melioration systems, in conditions of fluctuations and fluctuations of the water level in the irrigation canals. The significant adjustment time of the known device is explained. We can say that the pause time has a fixed value regardless of the mismatch error, however, the set pause time is optimal only with minimal values of the mismatch, and with significant mismatch values, i.e. with significant control actions of the regulator on the object to be controlled, the level changes faster, the set pause time is too long and therefore the object's transient time increases significantly, which can lead to overshoot and emergency situations to prevent which on the objects, it introduces external connections, providing a continuous (relay) control mode when the value of the permissible value specified for a particular object is exceeded Ani, which considerably complicates the system of automatic control in general gives .ne decrease control time. The aim of the invention is to increase the accuracy and reliability of the device and reduce the adjustment time. The goal is achieved by the fact that the discrete autocontroller containing a serially connected unit adjuster of the error meter, an inverter, a switch, an integrator with a discharge circuit, the first relay connected by an output to the integrator with a bit circuit, as well as the second and third relays, the outputs of which are connected respectively to the input of the control object and to the controllable input of the switch connected by the second information input to an output meter mismatch, introduced a shift register and a block specifying coefficients whose inputs are connected to outputs of the shift register, and one of the inputs - with the second and third relays inputs and an output - to a second input of the first switch, whose output is connected to the input of a shift register. The drawing shows a structural diagram of the proposed autoregulator. The circuit contains a lacquer meter 1, a setpoint 2, an inverter 3, an integrator 4 with a discharge circuit, a capacitor 5, a contact b, a relay 7 controlled by a dead zone, a ring shift register 8, a factor setting unit 9 and a polarized relay 10 with a switching group of contacts 11 with a neutral position, a relay 12 with a switching group of contacts 13, a control object 14. The coefficient setting unit 9 contains in the general case at least three settings K1, K2, short, for example switches or variable resistors, whose inputs connected, e.g., to a source of reference voltage, and outputs - through .elementy, switched signals output from the shift register .in ring 8, connected to the set input insensitivity relay zone 7 with a dead zone. The output of the autoregulator is a switching group of contacts 11 with a neutral position, to normally open 1M contacts of which is connected. The respective actuators of the reverse electric drive of the shutter. The device works as follows. At the first input of the error meter 1, a signal is received about the magnitude of the water level in the channel H; and to the second input - the value of the setting A from the setpoint 2. A signal proportional to the amount of matching between the setpoint and the actual value of the water level in the channel YN, a normally closed contact in the switching group of contacts 13 is fed to the input of the integrator 4, the output of which is linearly generated the increasing voltage, the polarity and the rate of increase of which are proportional to the magnitude of the agreement. In the initial state, in the ring shift register 8, the signal arrives at its first output and, therefore, the second input of the relay 7 with the dead zone receives the reference signal K1 from the coefficient setting unit 9, which determines the initial dead zone of the relay 7 with the dead zone . When the voltage at the integrator 4 output of the dead zone of the relay 7 with the dead zone exceeds the value set by the reference signal K1 from the coefficient setting unit 9, the relay 7 turns on and turns on the capacitor 5 discharge circuit. The capacitor 5 is quickly discharged, the relay 7 s dead zone releases, and therefore at its exit

a short pulse is generated which, at the input to the input of the ring shift register 8, causes a shift of the output signal from the output of the first to the output of the SECOND. This signal arrives at relay 12 and polarized relay 10. A moving contact in a switching group of contacts 11 of a polarized relay 10 closes the left or right (according to the diagram) normalization of open contacts, giving a signal to the corresponding actuator of the electric drive, depending on the sex discrepancy signal, to raise or lower the shutter. The movable contact in the switching group of contacts 13 of the relay 12 also switches and connects the input of the integrator 4 to the output of the inverter 3, and the second input of the relay 7 with the dead zone receives the reference signal K2 from the coefficient setting unit 9. At this time, the delay is formed and begins the formation of an impulse in the regulation cycle.

Inverter 3 reverses the phase of the input signal in such a way that a larger value of the DN error value corresponds to a smaller value of the signal at the output of the inverter 3. This signal, fed to the input of the integrator 4, causes a linearly increasing voltage to form at its output, thus is inversely proportional to the magnitude of the NA mismatch. When the dead voltage at the output of the integrator 4 of the dead zone of the relay 7 exceeds the value set by the reference signal K2 from the factor setting unit 9, the relay 7 with the dead zone turns on and turns on the discharge circuit with key 6, the capacitor 5 discharges quickly, the relay 7 with the dead zone releases and at its output a second short pulse is generated, which, arriving at the input of the ring shift register 8, causes a shift of the output signal from the output of the second to the output of the third. The polarized relay 10 and relay 12 return their contacts to the switch of the contact groups 11 and 13 to the initial state, the shutter movement stops, and a short-circuit reference signal is received from the coefficient setting unit 9 to the input of the relay 7 with the dead zone. This completes the formation of a pulse and the formation of a pause in the regulation cycle begins.

The input of the integrator 4 again receives a signal directly from the output of the error meter 1 and a linearly increasing voltage is formed at the output of the integrator 4, the rate of increase of which is directly proportional to the value of the error N. When the voltage of the integrator 4 of the dead zone of the relay 7 exceeds the dead zone of magnitude set by the reference signal of the short circuit from the Dani coefficient of coefficients 9, the relay 7 with the dead band is switched on again and turns on the discharge circuit with the key b, the capacitor 5 would SRW is discharged, the relay 7 releases the dead zone and is formed at its output

0 third short pulse, which, entering the input of the ring shift register. 8, causes a shift in the output signal from the output of the third again to the output of the first one and determines

5 return the entire circuit to its original state.

This completes the formation of a pause and the entire cycle of regulation. If there is an error signal AH at the output of the error meter 1, the adjustment cycle is repeated in the same order, and if there is no error signal, the auto-regulator circuit is in the deduction mode.

If there are fluctuations and pulsations of the water level in the channel, but with no actual mismatch, the amplitudes of the positive and negative half-waves are equal to each other, the voltage at the output of integrator 4 during the half-period of oscillations does not have time to reach the dead zone of the relay 7 with the dead zone set the reference signal K1 in the block of assignment of coefficients 9, and therefore oscillations and. water level ripple in the channel is not. cause false alarms of the controller and do not affect the operation of the controller. During the pulse and pause in the control cycle, the rate of rise of the output voltage of the integrator 4 varies in tune with the fluctuations and pulsations of the water level in the channel, but this also does not affect the accuracy and reliability of the autoregulator; the rate of increase of the output voltage 0 of neither the integrator 4 for the period is strictly proportional to the actual value of the error value. Thus, even in the presence of fluctuations and pulsations of the water level in the canal,

5 considerably exceeding the insensitivity zone of the autoregulator, the device operation is almost unlimited, with occasional bursts of water level

The channel 0 also does not affect the reliability of the formation of the control cycle.

The adjustment cycle, formed by the autoregulator, is formed from three. time intervals delay.

Claims (1)

5 impulse and pause in such a way that the impulse duration is directly proportional, and the delay and pause durations are inversely proportional to the magnitude of the mismatch H and at the maximum mismatch in the control zone the pulse duration has a maximum, .a delay and pause minimal values determined by the established values of the coefficients К1-КЗ. in the coefficient setting unit 9. This mode of operation of the autoregulator is the most optimal for regulating the water level in the canals of reclamation systems, provides a significant reduction in the adjustment time while improving the quality of the adjustment process and allows significantly improving the reliability of the entire automaton system. adjustment in the whole If there is a mismatch between the settings of the autoregulator in the cycle, the delay, impulse and pause at positive and negative values of these s misalignment that may occur onto some ryh hydro facilities, if they honor the variable coefficients in the coefficient setting unit 9 can be increased to six, that is, set different values of the parameters of the auto regulator depending on the polarity of the mismatch value; The economic efficiency of the proposed LAG discrete pulse width auto regulator for the melioration system is made up of the irrigation water saving achieved by increasing the accuracy and reliability of the device operation and by reducing the adjustment time transient processes in irrigation canals, as well as cost savings on the preparation, installation and maintenance of the auto regulator, the benefit the gift of eliminating elements and connections, increasing reliability and simplifying adjustment and adjustment of the device during its manufacture and operation. DETAILED DESCRIPTION OF THE INVENTION A discrete autoregulator for reclamation systems containing sequentially connected master, an error meter, an inverter, a switch, an integrator with a bit circuit, a first relay connected by an output to an integrator with a bit circuit, and a second and third relay whose outputs are connected correspondingly to the input of the control object and to the controllable input of the switch connected by the second information input to the output of the error meter, characterized in that, in order to improve the accuracy and the reliability of the device, a shift register and a block for setting coefficients are entered, the inputs of which are connected to the outputs of the shift register, and one of the inputs is input from the second and third relays, and the output is from the second input of the first relay, the output of which is connected to the input of the shift register . Sources of information taken into account in the examination of 1, USSR Author's Certificate No. 346711, class G 05 O 7/06, 1972., 2, USSR Author's Certificate No. 368586, cell. G 05 B 11/01, 1972. 3, USSR Copyright Certificate No. 4343/6, cl. G 05 B 11/28, 1974 (prototype).