SU557191A1 - Turbine automatic start device - Google Patents

Description

(54) DEVICE FOR AUTOMATIC STARTING TURBINE

one

This invention relates to the steam jet automachining.

Known devices dp automatic start of the turbine, containing an external controller, to which the sensors are connected

turbine metal temperature and load, as well as the warm-up speed controller they use the static dependence between the temperature of the metal of the turbine and the load, which only approximately characterizes the thermal state of the turbine at any given time at pu sk. Determining the inflection points of a static characteristic using a switch offset in a controller circuit to change the tuning slope causes additional difficulties. As a result, the turbine start-up is delayed

The start-up process has exceeded the specified limits of indicators of the state of the pipe, which reduces the reliability of its operation.

It is also known a device for automatic start-up of a turbine, containing a loading regulator connected to a control valve, and an analog computing unit with its piping metal temperature sensor connected to the input. 2

This device is closest to the proposed technical essence and the achieved result.

The disadvantage of the device is the somewhat reduced supersensibility of the turbine during start-up due to the COMPLEXITY of the analog computing unit, caused by the difficulties of modeling differential equations with large time constants.

The purpose of the invention is to increase the reliability of the turbine.

To achieve this goal to the input of the analog computing unit

The first output of the clock pulse generator is additionally connected, the second output of which is connected through a series of real and machine time interval counters and the decoder is connected to a 5-m unit connected to the computing unit with a load controller. The drawing shows the block diagram of the device. The device for automatic start-up of the turbine 1 contains a control valve 2 connected to the loading controller 3, a sensor 4 for the temperature of the metal of the turbine 1 connected to an analog computing unit 5 connected to the memory block 6 and to the clock generator 7, the second output which is connected to the after- wisely connected counter of 8 intervals of machine and real time, the decoder 9 and the memory block b. The device works as follows. When the turbine is heated, the voltage in the metal varies according to a complex exponential law depending on the metal temperature measured by the sensor 4. The turbine is lowered by the regulator 3 by means of the control valve 2 depending on the difference between the measured and actual (given) voltage values in the metal. The calculation of the voltage in the metal of the turbine is performed by an analog computing unit 5- operating on a machine scale.

of time.

The computer time intervals are defined by a clock pulse generator 7.

In real time from the beginning of the 40 start-up to the end of the warm-up (the whole process of starting the turbine) a certain time interval flows, which is divided into equal segments.

The interval for solving the di (|) of a potential equation describing the relationship between the temperature of a metal of a turbine and the voltage in a metal is divided into the same number of segments on a machine time scale.50

The generator 7 generates a signal that triggers the solution process in the analog computing unit 5, under the initial conditions corresponding to the temperature value measured by the sensor 4 at the given time 55. At the same time, the counting of segments in counter 8 begins from the beginning of the moment of the decision, moreover, one of the registers of the counter 8 pushes the segments of real time and the other of computer time. 60

The same values that appear in different registers of the counter 8 are determined with the decoder & com &. At the moment these values coincide, input 10 is connected.

Claims (2)

1. USSR author's certificate №418619, cl. F 01 D 19/02, 1972. 2. Leiserovich A. Sh. Energokhoz yast abroad, 1973, No. 6, p. 16. The memory block 6 to the output of the analog computing unit 5, at the same time in the latter the decision process is terminated. There is a fixup of the calculated value of the output parameter and its memorization until the next cycle. The fixed value of the parameter is compared in controller 3 with the specified value of the maximum permissible voltage in the metal of the turbine and the control signal of the control valve 2 is generated. Since the interval between cycles is small, the accuracy of the measured value is high. The greater the number of points and the smaller the time interval, the more accurate the resolution and adjustment process will be. The use of the device allows setting the turbine start-up tempo in accordance with the actual mode of its warming up, significantly increases the accuracy of solving differential equations with large time constants (up to 20-30 min) connecting the temperature of the turbine metal and the voltage in the metal, reduces the time start-up of the turbine and bring the start-up mode to the optimal one that does not allow exceeding the specified limit values of voltages in the metal of the turbine, which increases the reliability of the latter.