SU1068908A1 - Process for control of calorific power of hot-water boiler group - Google Patents

Abstract

1. METHOD OF MANAGING THE HEAT PERFORMANCE OF THE WATER BOILER GROUP by adjusting the temperature of the direct water flow and changing the fuel consumption and the rate of hot water recirculation in the boilers by reverse-flow water flow, T. lichat Due to the fact that, in order to increase the reliability of regulation, the rate of recirculation of hot water is changed according to the temperature of the water in front of the boilers, and the constant ratio of the flow rate of the back and forth flow of water is maintained by changing the pressure of the latter. 2. Method .OPP.1, which is also distinguished by the fact that, in order to improve the quality of regulation, the rate of recirculation of hot water is corrected by a dynamically converted forward flow temperature signal.

Description

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The invention relates to heat engineering, namely to the automation of heat sources of urban and industrial heat networks. There is a known method for controlling the heat output of a group of boilers by adjusting the temperature of the forward flow of water by varying the fuel consumption and the rate of recirculation of hot water in the boilers by reverse running the return flow of water. At the same time, the rate of recirculation of hot water is regulated by the water flow rate and each boiler til. The disadvantage of this method is that "the hydraulic mode of the boiler room is violated, which is defined. causes undesired fluctuations in interlocking recirculation and reverse flow bypass circuits. In addition, the temperature of the water in front of the boilers is not maintained at the required (according to the instructions, etc.) level, which reduces the reliability of the boilers in operation. The purpose of the invention is to increase the reliability and quality of regulation. This goal is achieved in that according to the method of controlling the heat output of a group of boilers by adjusting the temperature of the forward water flow by changing the fuel consumption and the rate of recirculation of hot water in the boilers by reverse-flowing water, the rate of recirculation of the hot water 4 varies with temperature water in front of the boilers, maintain a constant ratio of flow rates of the direct and reverse flow of water by changing the pressure of the latter. In addition, the multiplicity of hot water circulation is adjusted by the dynamically converted forward flow temperature. The drawing presents a system that implements the proposed method. The system contains 1 return and 2 direct pipelines of the network water, group of boilers 3, control valve 4, pump 5, control valve 6, network pump 7, control valve 8, sensor 9 of the temperature of the direct network water, program controller 10, outdoor temperature sensor 11, temperature controller 12, correction controller 13, recirculation controller 14, differentiator 15, water temperature sensors to boilers, water flow sensors 17 and 18, pressure regulator 19, integrator 20, block 21 Comparison with the dead band. Switch 22 and reverse link 23. The system is as follows. With the established ratio of water flow in the reverse 1 and forward .2 pipelines, the pressure regulator 19 is balanced. Deviations of the water temperature in front of the boilers are processed by the regulator 14. Recirculation results in a change in the recirculation ratio of valve 6, and the violation of the ratio of flow rates in the reverse 1 and forward 2 pipelines is quickly restored by the regulator 19 pressure .-. Water temperature fluctuations in the straight pipe 2 are suppressed by the temperature controller 12 by changing the position of the valve 4; whereby cold water is mixed in from the return line to a greater or lesser extent. The output effect of the temperature controller 12 is stored on the integrator 20 of the correction regulator 13 and, taking into account the channel gain, additional burner devices of the boilers 3 are turned on or off. Since each position of the switch 22 corresponds to a specific composition of the burners, it is possible. Experimental dependence of the change in the amplification ratio of feedback 23, corresponding to the degree of influence of the included burner on the water temperature at the outlet of the group of boilers 3. Thus, the redistribution of the flow of water through the boilers 3 and besides them is not affected by the temperature of the hot forward water. The temperature controller 12 works similarly when the setting of the program from the program controller 10 changes. The graph is set by the temperature of the forward flow depends on weather conditions and the time of day, as possible modes with a decrease in the temperature of the direct flow at night. In this case, the change in the hydraulic resistance of the section between the return port 1 and the forward 2 pipelines will be compensated for by the high-speed pressure regulator 19. Taking into account the dynamics of the system circuits, notej that the connection from the temperature controller 12 through the differentiator .15 to the recirculation controller 14 makes the latter invariant to the operation of the controller 12, since possible deviations of the water temperature in front of the boilers are prevented by the impact of the recirculation valve b. The introduction of heat output control of a boiler house by parallel impact on fuel consumption in boilers and measuring the degree of cold water bypass and return flow to the forward match the inertial disturbance suppression circuit of hot water by boilers and speeds, the reverse water bypass contour in addition to boilers, prevents their swinging. Introduction to the operation of the water pressure regulator 19 contributes to the achievement of the autonomy of the operation of the circuits in various modes.

Thus, the method is implemented in the proposed system, since this eliminates the effect of undesirable cross-links between

control loops, the invariance of the hydraulic and temperature regimes of the boiler room is achieved, and the reliability and quality of the control is increased.

Claims (2)

1. WAY OF CONTROL OF HEAT PRODUCTIVITY OF A GROUP OF WATER BOILERS by adjusting the temperature of the direct flow of water by reducing the fuel consumption and the rate of recirculation of hot water in boilers bypassing the return flow of water, about -. lich. Keep in mind that, in order to increase the reliability of regulation, the rate of recirculation of hot water is changed according to the temperature of the water in front of the boilers, a constant ratio of the flow rates of the direct and reverse water flow is maintained by changing the pressure of the latter. 2. The method according to claim 1, characterized in that, in order to improve the quality of regulation, the frequency of recirculation of hot water is adjusted according to the dynamically converted $ signal of the direct flow temperature, ι £ 1C68908