SU676739A1 - Turbine heat load regulating device - Google Patents

Description

yes network water. The controller 8 also includes a control unit 13 and the controller 14 of the available heat load with sensors 15 and 16 of steam consumption at the entrance to the selection chamber 2 (flow rate: steam through the turbine's pre-selection stage).

The device operates as a heat exchanger heat load stabilizer under the condition of nominal steam flow through a turbine or with the input of limiting heat load under conditions of reduced steam flow per turbine. From turbine 1 from chamber 2 by steam line 3 into the heat exchanger 4 enters the bar "a - heating network water 5. The amount of incoming steam can be changed by the regulating valve 6 from the actuator 7. The actuator 7 operates from the regulator 8 consumed heat, signal which is formed through the multiplier 9 from the temperature sensors 10 and 11 and the flow sensor 12. It is compared with the signal from the setting unit 13. The multiplier 9 receives signals from the temperature sensors 10 and 11 with different signs, which allows to allocate a signal equal to temperature differences at the outlet and at the entrance to the heat exchanger 4. The signal from the sensor 12 for mains water flow, multiplied by the temperature difference signal, produces a signal equivalent to the amount of heat consumed. This equivalent signal from multiplier 9 is compared with the reference on controller 8, and if these signals are unbalanced, a command is generated to the actuator 7.

The action of the regulator 8 of heat load with increasing amount of network water proceeds as follows.

The signal from the flow sensor of the supply water increases with increasing flow, the temperature difference between the outlet and the heat exchanger at the initial moment is unchanged. The signal from multiplier 9 increases, and regulator 8 generates a command for partial closure of control valve 6 by the actuator 7. As a result of partial closure of the clanan, the temperature of the outlet water from the heat exchanger decreases. At the same time, the amount of heat consumed should be kept unchanged. Thus, the controller 8 will retain the heat load on the heat exchanger 4, i.e., it acts as a stabilizer of the heat load of the heat exchanger.

Under the conditions of a partial steam turbine load, in order to protect the pre-selection stage against overload, it is necessary to reduce the steam consumption to the heat exchanger. This task is performed by the controller 14 of the available thermal

load, the signal from which the nominal flow of steam through the turbine is zero, and when the load of the turbine decreases. This signal is summed with the setpoint 13 signal. The regulator command is activated by pressure sensors 15 and 16, which characterize the steam flow in the turbine through the pre-selection stage. For a condensation turbine, such a signal may be a signal for the electrical power of the generator or a signal for the pressure in one of the high-pressure chambers. Under the action of the controller 14 of the available heat load in the case of a decrease in POWER of the turbine, a command is formed to limit the amount of heat consumed in the heat exchanger 4.

This device for controlling the heat consumption in multi-stage circuits

heating water increases accuracy and allows for the normal operation of the equipment without interfering with the operation of turbines and their arbitrary power changes, i.e. autonomy is achieved

operation of turbines in the presence of technological connection by heat load through network water. Regulator of available heat load provides protection of pre-selection stages.

As a result, the reliability and cost-effectiveness of step-heating circuits increases.

Claims (2)

1. USSR Author's Certificate No. 376587, F 01 K 17/02, 1972. 2. Rabinovich A.V., et al. Electro-hydraulic control system for a cogeneration turbine. “Electric stations, 1975, No. 11, p. 33-35.