SU1681041A1 - Method of setting technological minimum of loading of hydraulic unit and device for its performing - Google Patents

Abstract

The invention relates to hydropower. The purpose of the invention is to increase reliability when starting up a hydraulic unit to isolated consumers. The device contains serially connected measuring converter 1, shaper (F) 2 of. PID law with an iterator (I) in a direct circuit, an electro-hydraulic tracking system 4 with feedback on the position of the servomotor. The first input of the comparator (K) b is connected to the output F 2. The output K 6 is connected via a double switch (B) 7 to the input I 3, the Output of the setting device through B 7 is connected to the second input K 6. The first input of the logic device 9 is connected to the output Repeater Switch Generator

Description

FIELD OF THE INVENTION The invention relates to hydropower and can be used in the control of hydraulic units.

The purpose of the invention is to increase reliability when starting up the hydraulic unit for isolated consumers,

FIG. 1 shows a block diagram of the proposed device; in fig. 2 is a diagram of this device.

The device contains a measuring transducer 1 connected in series, a driver 2 according to the PID law with an integrator 3 in a direct circuit, an electrohydraulic tracking system (EGSS) 4 with reverse connection to the position of the servo motor 5, a comparator 6, the first input of which is connected to the output of the rapper 2 and output through a double switch 7 with the input of the integrator 3, the driver 8. whose output through the switch 7 is connected to the second input of the comparator b, the logic device 9, the first input of which is connected to the repeater output the key switch of the generator, the second input - with the output of the comparator 6, and the output - with the control input of the switch 7, and the voltage divider (10) installed in the circuit between the output of the comparator 6 and the input of the integrator 3. The device is equipped with an additional comparator 11 with an adjustable threshold and the element OR 12, the first input of which is connected to the output of the main comparator 6, and the output to the second input of the device 9, while the output of the converter 1 is connected to the input of the comparator 11, and the output of the latter is connected to the second input of the element OR 12. Device ystvo also comprises an adder 13, sensor 14, power amplifier 15, the electromechanical converter 16, the main valve 17 and a selector 18.

The method is implemented as follows.

The device is preliminarily prepared for operation in the set of technological minimum by applying voltage from the output of the repeater generator switch to the input of the logic device 9.

After that, the rotation frequency of the hydraulic unit is measured, a signal of the actual frequency error is generated, the last signal is sent to form

the control effect on the EGSS into the driver 2. Simultaneously with the measurement of the frequency, a signal is set that corresponds to the permissible frequency deviation from the nominal one;

mismatch of a given deviation, when they are equal, form the first logical signal, which is fed to the extraction channel to automatically load the signal generation to stop

movement of the guiding apparatus to open the OR element 12. Simultaneously with the measurement of the rotational speed, a signal is also generated to open the guiding apparatus by generating a reference setting signal of the guiding apparatus equal to the technological minimum of the load, generating the last signal error signal and controlling the output of the driver 2 according to the PID law), the formation of the last signal of the mismatch signal to open the guide vehicle. The signal for opening the guide vane is applied to the formation of an activating effect on the EGSS in shaper 2 according to the PID law.

Upon reaching a predetermined value of the opening of the guide vane (with the equality of the task signal to open

the guiding apparatus and the signal at the output of the block) generate a second logic signal and also feed it to the take-up channel to automatically load the signal generation to stop the movement to open the guiding apparatus to the OR 12 element.

According to the first higher order of the two logical signals, the third logical signal in the OR element is formed.

12, it stops the signal to the control input of the switch, and thereby stops both the formation and the signal to open the guiding apparatus.

The device works as follows.

Upon reaching the nominal rotational speed in idle mode, when the error signal is zero, the start of the technological minimum of the load begins with the inclusion of the generator repeater. In this case, the signal from the repeater of the generator is fed to the first input of the logic device 9, which generates a switch-on signal for the switch 7.

The last signal closes both groups of contacts of the switch 7 and the signal of the driver 8 is fed to the input of the comparator 6, in which it is compared with the signal from the output of the driver 2. At the signal values from the output of the driver 8, larger than the last signal, the comparator 6 generates a signal the opening of the guide vane, which is supplied through the divider 10, in which the magnitude of the signal is formed, is necessary to ensure the driving speed specified by the condition of reliable operation of the movement generator for opening the guide ramp rata hydraulic unit. The last signal is fed through the second group of contacts of the switch 7 to the second input of the integrator 3 of the driver 2.

In the driver 2, a signal of the total control action is generated depending on the frequency and the signal on the opening of the guiding apparatus, which is fed to the adder 13 of the EGSS 4, which is also fed to the signal from the sensor 14 of the position of the main servo motor 5.

In the adder 13, an error signal is generated, which, through the power amplifier 15, is fed to an electromechanical converter 16, where it is converted into movement of the main spool 17 of the servomotor 5.

When the frequency exceeds its nominal value while the guide apparatus is moving to open, which can occur when the hydraulic unit is switched on to isolated consumers, a frequency error signal is generated, which is fed both to the input of the driver 2 and to the input of the comparator 6. When the last signal is equal and the magnitude of the threshold of operation of the comparator 6 at the output of the latter, a positive polarity signal is generated, which is fed to the first input of the OR 12 element. Upon reaching equal output signals the driver 2 and the signal of the driver 8, which is considered in the proposed device as the moment of reaching the predetermined opening of the guide vehicle, in the comparator 6, a positive polarity signal is generated when the predetermined opening is reached, which through the selector 18 enters the second input of the element OR 12. The element OR 12 is the first signal at its input, the signal is generated by a logical signal, which is fed to the second input of logic device 9, which disconnects the supply voltage to the relay of switch 7. As a result, the contacts

10 of the switch 7 is opened, the signal of the driver 8 to the input of the comparator 6 stops and the signal from the divider 10 to the second input of the integrator 3 of the driver 2 is disconnected and thereby turns off

Claims (2)

15 load set, i.e. the movement of the opening guide stops. Claim 1. Method of recruitment of technological minimum load of hydraulic unit, including 0 measurement of the rotational frequency of the hydraulic unit, generation of active frequency error signals for opening the control unit and their supply for generating a control signal on the electrohydraulic tracking system of the frequency control unit and power of the hydraulic unit, generating a signal for the control signal of the control action and position the main 0 of the servomotor of the guide vane and the termination of the signal to open the guide vane when it reaches the predetermined opening, characterized in that, in order to increase reliability when When the hydrounit is started up on isolated consumers, the admissible frequency deviation from the nominal frequency is additionally set, and the signal to open the guide vanes is also stopped when the permissible frequency deviation from the nominal value is reached. 2. A device for recruiting the technological minimum of the load of the hydraulic unit, containing series-connected 5 measuring transducer, former using a PID law with an integrator in a direct circuit, an electro-hydraulic tracking system with feedback on the servo motor position, a comparator, the first input of which is connected to the output of the imager, and the output through a double switch with the integrator input that sets a device whose output through a double switch is connected to the second input of the comparator, 5 logic device, the first input of which is connected to the output of the generator repeater switch, the second input to the comparator output, and the output to the control input of the double switch, and a voltage divider installed in the circuit between the output of the comparator and the input of the integrator, characterized by that. that, in order to increase the reliability of the hydraulic unit when starting on isolated consumers, it is equipped with an additional comparator with an adjustable response threshold and an OR element, the first input of which is connected to the output of the main comparator, and the output - to the second input of the logic device, while the output of the measuring converter is connected to the input of an additional comparator, and the output of the latter is connected to the second input of the element OR.