SU1250663A1 - System for controlling a steam turbine plant - Google Patents

Description

The invention relates to a power system and can be used in the regulation of steam turbines.

The purpose of the invention is to improve the maneuverability of the installation by improving the processes of controlling the steam temperature downstream of the separator-superheater.

FIG. 1 shows a functional diagram of a steam turbine control system; in fig. 2 - Characteristics of the functional converter; in fig. 3 characteristic of an additional functional converter.

A high-pressure cylinder 1, a separator-superheater 2, a low-pressure cylinder 3, a condenser 4 and a generator, t operating on the network 6. The power sensor 7, connected to the control system, is connected to the functional input of the converter. 8, 151) the stroke of which is connected to the input of the setpoint 9 of the maximum temperature difference of the metal along the flange width. The output of the setpoint knob 9 of the maximum temperature difference of the metal over (norin f; 1a 1a and the output of the sensor K) of the metal temperature of the flange is connected to the input of the adder 11. The output of the adder 11 is connected to the input of the additional functional converter 12, the output of which is connected together with the pressure sensor 13 is heating ) riapa separator-steam supply; 1 to the input of the first room 14. The outputs of the first 14 and second 15 comparators are connected to the input of logic unit 1 (1, the output of which through the actuator 17 is connected to valves 18 1 . Separator-superheater Vgchody sensors 19 and 20 metal temperature; 1a respectively the outer and inner surface of the flange and an outlet; 1adatchika 9 marginal difference tem-) Atur meta 1la Connectivity: 1yucheny to the inputs of the second comparator 15..

The input of power sensor 7 is connected to generator 5. Metal temperature sensors 10 and 19 are mounted on the outer surface, and sensor 20 on the inner surface of the flange of the cylinder 3 is of low pressure. The sensor 13 of the pressure of the i-cutting steam sen- sor RAO) a-superheater is installed behind the heating steam valves, connected between the input qi, 1 high pressure 1 and the heating steam inlet of the separator-steam-valve 2.

The input signals of the logic unit 16 are) allowing the passage of the control signal (the output of the comparator 14) and blocking the signal (the output of the separator 15).

The output of logic unit 16 is a signal for actuator 17.

The control system of the steam turbine works as follows.

In the process of loading the turbine, the steam flow to the high-pressure cylinder 1 increases, which leads to an increase in the power delivered by the generator 5 to the network 6.

The power sensor 7 acts through the functional converter 8 and the sensor 9 of the maximum temperature difference of the metal across the flange width to the input of the adder 11. The signal of the metal temperature sensor 10 to the outer surface of the flange arrives at the other input of the adder. At the output of the adder 1 I, a control signal of the permissible value 1ppdop of the steam temperature behind the separator-superheater, which is defined as

tiifi doi - l. I (n) almer before,

where (chgg metal temperature;

f () is the functional dependence of the converter 8 (two examples of such dependences are shown in Fig. 2 — curves A and B); .l limiting temperature difference

metal.

(The adder 11 acts on an additional functional converter 12. At the output of the functional converter 12, a control signal is formed for the allowable value Rppdop of the heating steam pressure behind the control valve, defined as the function fi (tnri dop.) Allowed.) Tun values and the vapor temperature behind the separator - reheater (fig. 3).

NPD D (|| T I I (tlHI DON).

The control signal Ppp .wn and the signal Ppp of the current pressure, taken from the pressure sensor 13 of the heating steam of the separator-superheater, act on the comparator 14. If the signal values satisfy the condition (Rmp Rome house), the first comparator 14 acts on logic unit 16 such Thus, the difference between the signals (Rppd.l - Rip) goes to the executive

a mechanism 17 in the form of a control signal for opening the valves. Otherwise, the comparator 14 issues a command to move the valves of the heating steam in opposite. south side (closing valves). The sensors 20 and 19 of the metal temperature tvit T hr and 1 mhtnar, respectively, the inner and outer flange surfaces and the setting device 9 of the average temperature difference of the metal act on the second comparator 15. If the signal values satisfy the condition (1 m, rh 1 ".nm. Mm1-ttfed) . The comparator does not interfere with the passage of control action 1 (Rpp dop - Rpp) to the heating steam valves. Otherwise, it uses logic block 16 to prohibit the passage of control action (Pnn.iori - Rpp) on the heating steam valves. .

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Claims (1)

SYSTEM OF REGULATING A STEAM TURBINE INSTALLATION, comprising a power sensor connected through a functional converter to the input of the limiter of the temperature difference across the width of the flange, the output of which, together with the output of the temperature sensor of the metal of the flange, is connected to the input of the adder, connected by its output to the input of the first comparator, the output of which is shared with the output the second comparator is connected to the input of the logic unit associated with the actuating mechanism of the valves (floating pair of the superheater separator. which, in order to increase the maneuverability of the installation by improving the process of controlling the temperature of the steam behind the superheater, the system is equipped with an additional functional converter, a pressure sensor for the heating steam of the separator superheater.1 and temperature sensors of the metal of the inner and outer surfaces of the flange, the pressure sensor heating steam is connected to the input of the first comparator, meta temperature sensors, the evil of the inner and outer surfaces of the flange together with the limiter nd temperature difference - to the inputs of the second comparator, and the supplement '.! A new functional converter is connected between the output of the adder and the input of the first comparator. FIG I 1250663 A1