CS204831B1 - Digital adaptive control unit for mixing valves of central heating - Google Patents

Description

COPYRIGHT CERTIFICATE DESCRIPTION OF THE INVENTION CZECHOSLOVAKCASOCIALISTREPUBLIC (1S)

/ 22 / Logged in 19 10 79/21 / / PV 7106-79 / 204831 dl) (81) (51) Int Clr 24 H 9/20

OFFICE OFFICE

AND DISCOVERIES (40) Posted 3 1 07 80 (45) Published 15 06 82 (75)

Author of the invention CHALUPA VÁCLAV doc. CSc. and hSeBACka IVAN ing., PRAGUE (54) digital adaptive regulator of central heating mixing valve 1

BACKGROUND OF THE INVENTION The present invention relates to a digital adaptive controller for automatically adjusting the rate of return and return water by means of a four-way mixing valve connected to a central heating hot water boiler equipped with a circulation pump.

The mixing ratio regulators used so far are based on the classical principle of feedback controllers linear with different correction elements, nonlinear and most often trailing regulators. Optimal regulators exist, but they are complex because they must include circuits for solving mathematical or logical operations, they may include a microprocessor. These regulators must necessarily be equipped with temperature sensors located at different points in the heating system and in the outside.

These disadvantages are eliminated by the digital adaptive regulator of the central heating mixing valve according to the invention. It consists in the fact that it consists of a space thermostat with an electric motor switch of a circulating pump connected simultaneously to a forming circuit, the output of which is connected by a first return counter. Further, the output of the shaping circuit is connected to the input of the second control block, which is connected to the second bore counter. The output of the first counter is connected to the input of the second counter and the outputs of the first block and the second block are connected to the inputs of the evaluation circuit, the output of which is connected to the actuator of the mixing valve. Further, a first pulse source 2 is connected to the first control block and a second pulse source is connected to the second control block. An advantage of the digital adaptive controller of the four-way mixing valve is the relatively simple implementation of the readily available components at reasonable cost. Furthermore, the digital adaptive controller of the invention makes it easy to implement the accelerated process of finding the optimum starting position of the four-way mixing valve. a cold object, or a large change in the reference temperature.

BRIEF DESCRIPTION OF THE DRAWINGS The invention and its advantages will be explained in more detail with reference to the accompanying drawing, in which an overall block diagram is shown. the digital adaptive controller according to the invention comprises a spatial thermostat 11 by means of a switch of the electric motor A of the circulation pump connected simultaneously to the shaping circuit 26. Further, the input of the second control block 6 is connected to the output of the shaping circuit 2 and is coupled to the second return counter 8. The output of the first return counter 5 is connected to the input of the second return counter 8 and the outputs of the first control block 3 and the second control block 6 are connected to the input of the evaluation circuit whose output is connected to the actuator 10 of the mixing valve B. the first pulse source is connected and the second pulse is 204831

Claims (1)

204831 of the control block, a second pulse source 7 is connected. The forming circuit generates logic signals representing the pump pump function information. These logic signals are routed to the first block 3 of the control of the first counter 5. When the electric motor A of the circulation pump is triggered, the corresponding logic signal is influenced by the first control block 3 of the first return reader to pass the output pulses from the first pulse source 4 to the first return counter 5. The first control block 3 receives feedback information from the first counter 5 ' The content of the first counter 5 ' is proportional to the running time T1 of the circulation pump. During the period Tj, the heating medium of the heating system is supplied and its value is bounded by the moment of switching the room thermostat when the set temperature in the reference room is reached. At this point, the circulation pump is stopped and at the same time the logic signal at the output of the shaping circuit 2 is changed. As a result, the first control block 3 stops counting the first return counter 5_ in front, opening the counting direction backward. The backward counting time T2 is limited to the point when the temperature in the reference room decreases the value given by the room thermostat insensitivity band, for example 0.4 ° C. At the end of the time interval T2, one natural cycle is terminated. The content of the first counter 5 is proportional to the difference t 1 - T 1. In order to register the second and further natural cycles of the function of the digital adaptive central heating controller, the contents of the first counter 5 are overwritten to the second counter 8, whereby the first counter is ready to register and evaluate the next natural cycle. The operation of the digital adaptive central heating controller automatically realizes the optimum positioning of the four-way mixing valve such that at a steady state of the system, Tj = »2., Ie, for the time of the heating of the object in each natural cycle is equal to its cooling time o constant temperature value given by the space thermostat insensitivity band The correction of the position of the four-way mixing valve after the end of each natural cycle is proportional to the difference Tj-T2, ie the content of the first counter 5 and after handover PÉE EDM M TV that it consists of a room thermostat (1) with a switch of an electric motor (A) of a circulating pump connected simultaneously to a shaping circuit (2), the output of which is connected to a first block (3) control, which is connected to the first return counter (5), and le is the forming output circuit (2) is connected to the input of the second block (6) of the control which is connected to the second counter (8), and the content of the second counter (7). a second control block to a second return counter £. These pulses are simultaneously fed to the evaluation circuit 2 which generates an electrical signal for the actuator 10, the duration of which is proportional to the difference in time T 1 - T 2. The direction of rotation of the actuator 10 is also determined by the evaluation circuit 9, based on information from the first control block 3 ' of the first counter 5 ' T2> Ie. The arrangement of the digital adaptive regulator according to the invention makes it possible to easily realize the accelerated process of finding the optimum starting position of the four-way mixing valve either during the first heating of the cooled-down object or with the high temperature reference value in the reference room. In these cases, the evaluation circuit executes a so-called accelerated intervention after a pre-selected period Tj or T2 has elapsed. The accelerated intervention process is that after the preselected time T 1 or T 2, the first return counter 2 »is reset, which starts to measure Tinebo T2 again. return counter «5 and new measurement. This situation is repeated for a long time, up to the respective times T 1 and T 2, for values lying within a pre-selected interval. In the accelerated intervention process, the evaluation circuit 6 generates electrical signals for the actuator 10 several times, which is proportional to the maximum difference of the times T1-T2, which allows a faster targeting of the mixing valve position T1 and T2 are smaller than a pre-selected value. the digital adaptive controller of the central heating mixing valve according to the invention is relatively simple to implement by digital integrated circuits. Compared to the analogue version of the adaptive controller, however, it is advantageous to substantially reduce the transients in the process of finding a new starting position of the mixing valve at large variations in ambient temperatures, possibly large variations in the reference temperature in the reference room. YNALEZ, wherein the output of the first counter (5) is connected to the input of the second counter (8) and the outputs of the first block (3) and the second block (6) are connected to the inputs of the evaluation circuit (9), the output of which is connected to the actuator (10) of the mixing valve 3f, and a first pulse source (4) is connected to the first control block (3) and a second pulse source (7) is connected to the second control (6). 1 sheet drawings Sťveroprafi ·. n. div 7, Mott