SU1444731A1 - System for automatic control of water main temperature - Google Patents

Abstract

The invention relates to systems for the automatic control of the temperature of network water in district heating heaters installed at CHP plants and in boiler houses that carry the heating load. The purpose of the invention is to increase the economy of fuel consumed for heating network water by taking into account the outdoor temperature. For this purpose, in the system of automatic control of the temperature of the supply water, there are sensor 4 and transmitter 5 of the outside air, setting devices 2 and 3, respectively, the minimum temperature of the outside air and the maximum temperature of the supply water, connected through the corresponding blocks 6-8 matching to the corresponding inputs of the adder 9 connected through the switch 10 with one of the inputs of the temperature controller 11, which forms the control signal for regulating the steam supply by the regulator 16. 2 Il. (ABOUT

Description

4 4

WITH

The invention relates to systems for the automatic control of the temperature of network water in district heating heaters installed at CHP plants and in boiler houses that carry the heating load.

The purpose of the invention is to increase the economy of fuel consumed for heating network water by taking into account the outdoor temperature.

FIG. 1 shows a block diagram of the system; and in fig. 2 is a graph of mains water temperature versus outdoor air temperature.

The system contains an outdoor temperature sensor 1, a setpoint 2 of the minimum outdoor temperature, a setpoint 3 of the maximum water temperature, a water temperature sensor 4, a setpoint 5 of water temperature, blocks 6-8 signal matching, an adder 9, a switch 10 used to switch the system to the control mode from setpoint 5 in case of malfunctions in the task correction circuits, temperature controller 11, signal matching unit 12, control unit 13, allowing personnel to switch from automatic control to remote control. Next, the system includes a magnetic starter 14, an actuator 15 and a regulator 16.

As elements of the system, in particular, elements of the MKTA Cascade system can be used, as temperature sensors - resistance thermometers of the type gr. Ml00 with a converter to a current signal, temperature adjusters - resistors of the MCP type, manual control unit of the ZU-05 type.

The system works as follows.

With the established external temperature, the system. I am in the stationary mode and the signal from the sensor 4 of the network water temperature is equal to the signal generated by the adder 9 in accordance with the following equality

J. Khmats. „J-MUH. I „f

tfL-e п-в .e rmLH., where tn.s is the specified value of the temperature of the network water;

 p.v - the maximum temperature of the network water according to the schedule of the heating network; Minimum outside temperature according to the schedule of the heating network;

that is the slope of the temperature graph of the heating network. Together with the signal based on the actual temperature of the mains water from the sensor 4, the signal formed by the adder 9, respectively, of the outdoor air temperature, through the switch 10 enters the input of the controller 11, where both signals are summed algebraically and in the case of imbalance. Mt / M - N.

an action which, through block 12, block 13 and magnetic starter 14, turns on the actuator 15 of the regulator 16. As a result of this effect, the steam flow rate to the network heater is changed, which brings the temperature of the network water to its calculated (optimal) for a given outdoor temperature by value.

For example, in a heat network operating in accordance with the schedule of FIG. 2, at a temperature of t ".6 {-15) ° C (285K), the temperature of the supply water is maintained at (+74) ° C (347K) and the temperature of the outside air changes to. (- 25) ° C (248K) - Tangent angle slope of the temperature plot is

 137.8 - 124.4. ,,, 102.1 - 85.3

This multiplier is set on the dividers of the signal of the inputs of the adder 9, to which the sensor 1, setpoint 2 is connected.

Thus, at the first input of the adder, a current signal is received that is proportional to the resistance at the outside air temperature, which is 1ne. (-25) ° C and the copper resistance thermometer corresponds to the value of 89.5 C) m, the second input of the adder 9 receives a current signal proportional to the minimum resistance value, according to the mode map at the lowest temperature of the coldest day (in this m case it is (-35) ° C, to which the resistance of the copper thermometer is 85.3 Ohms. In correlation with the control algorithm, both signals go to the inputs in antiphase. The third input of the adder is given a signal proportional to the maximum value of the temperature of the network water at the lowest outdoor temperature when changing this

0

A copper thermometer has a resistance of 137.8 ohms. According to the proposed control algorithm, the calculated temperature value at a given outdoor temperature and a given 5 mode map is

VB 137.8-0.8 (89.5-85.3) 134.44 ohms

(355K) ..

With the existing manual input system for setting a task to adjusting the temperature of the network 0 water, the boiler operator on duty must, according to the same regime map, enter the setpoint resistance equal to

tn.B 137.8-3.36 134.44 ohms.

Thus, the proposed system. MMA continuously adjusts the task to the controller when the outside temperature changes with the required accuracy.

At the same time, the system has a higher speed. Both of these factors save fuel on the production of hot water.

Claims (1)

Invention Formula The system for automatically controlling the temperature of the network views, comprising a water temperature sensor and serially connected water temperature sensors, a temperature controller, a signal conditioning unit, a control unit, a magnetic starter, an actuator and a regulator mounted on the steam supply line, that, in order to increase the economy of fuel consumed for heating network water, by taking into account the outdoor temperature an air temperature sensor, an outdoor temperature minimum temperature setter, a maximum water temperature setpoint device, three signal conditioning units, an adder and a switch are entered into the system, with the outputs of the outdoor temperature sensor, the setpoint temperature indicator and the maximum water temperature setting unit signals are connected to the corresponding inputs of the adder, the output of which is connected to the first input of the switch connected a second input to the output water temperature setpoint, and output - to the second input of the temperature controller of the torus. (SCHZom) ZbZk () 238 UQ 258,268 85, The temperature of the outside 2