SE464985B - CONTROL DEVICE CONCERNING ONE OR MULTIPLE CONTROL ORGANIZATION IN A FLUID DUCTING PIPE OF A FLOWING MACHINE - Google Patents

Description

464 985 feefef ~~ - Fig. 2 shows the operating plan for a control with two controls subsequent integrators. i 1 denotes a control device, one input of which is supplied the signal x d, which corresponds to the difference of the quantity to be regulated, e.g. the steam flow. The output signal from the control device 1 is applied partly as setting variable signal Y over line 2 the drive device (not shown) for a control body such as a control valve, control valve or similar and partly over the line 3 without delay one input on one controlled subsequent integrator 4. The output signal from the integrator 4 is applied the upper line 5 without delay the first input of a summing means 6, the second input of which is supplied with the value + A output from a block 12A line 7 without delay. The output of the summing means 6 is over line 14 connected to the EC input for setting the setting size heat up. The output signal from the integrator 4 is further applied to the upper line 9 the positive input to a summing means 11, the negative of which input upper line l1 is connected to the output of a block l2B, which delivers the value -A. The output of the summing means 10 is over the line 13 provided with the EU entrance for limiting the setting variable downwards.

By the aforementioned controlled subsequent integrator 4 is meant one apparatus or a coupling device, the output quantities of which follow its input quantity at an externally given speed. the integrator 4 is provided with two additional inputs for the control variable (allowed transient upwards) xwl and for the control variable (permissible transient downwards) xwz, where they are from the outside the supplied quantities xwl and xwz determine the permissible integration the speed (initial quantity of the change rate) upwards and down. The design of a controlled subsequent integrator 4 is known per se in connection with an externally supplied control variable xw from DE-OS 3,500,482.

You can also use several controlled sequential integrators.

For example, as shown in Fig. 2, the summing means 10 may also be connected with the output of a separate, ie. of the integrator 4 independently, integrator 4 '. In this case, each integrator with the two control quantities is supplied xwl and xwz.

The quantity A, which is to be added to the signal from the integrator 4, and the quantity A to be subtracted from the integrator signal is determined in depending on the control task so that spontaneous changes in the setting of the control device with the value 4 can be tolerated by the the distance or by the parameters directly affected by the control variable. 4-64 985 3 In the case of steam turbine controls, the quantity A is determined e.g. so that end- settings of setting variable 5 Å from an equilibrium state can not yet cause an excessive thermal stress on the housing of the steam turbine. About due changes in setpoint or control variable changes in setting size is implemented, the setting variable can spontaneously change with the value A, while the following additional changes can only be implemented so quickly, that changes occur along the voltage limit.

The values + A and -A can also be used for corresponding applications. traps be variable given parameters. They may also be associated with a mathematical function with the permissible speeds of changing the setting size.

The proposal according to the invention can also be used in the regulation of the load of a flow machine, if a limitation of the working media current change is desired. _ Another use case would be the pump limit control of the compression where difficulties arise, if border regulation intervenes. With it the proposed coupling can be switched to even before the boundary curve is reached limited setting speed, so that the intervention of the boundary relay device can be softer.

The control device according to the invention works in the following way: In the leveled state, the setting quantity of the control device is 1 and the output quantities of the integrator 4 and the output quantities of, respectively integrators 4 and 4 'of equal size, so that the setting variable at fast fluctuations (changes) of the control variable or the control variable can follow in corresponding to the desired dynamics of the control device, until they - to the output from the integrators 4 and 4 '- the limit values + A or -A are achieved. The output of the integrator or integrators follows the control setting the quantity at the permitted speed and thereby assumes an average value of setting variable and limits on setting variable changes, such as would exceed the quantities in the A setting speed to that in the integrator prepared the permissible rate of change or to the the permitted rates of change.

Claims (2)

464 985 PATENT REQUIREMENTS Control device for actuating one or more control means in a fluid-carrying line of a flow machine, in particular ang turbine, each having an input for limiting the setting variable upwards and downwards, respectively, characterized in that the control means for limiting the setting variable upwards ) increased the initial value from a controlled subsequent integrator, and to the control input for limiting the setting variable downwards is connected the output value reduced by the quantity (A) from the aforementioned integrator (4) or another controlled subsequent integrator (4 '). Control device according to Claim 1, characterized in that the quantity (A) amounts to 10% of the initial value of the controlled subsequent integrator or the controlled subsequent integrators.