DE3213222A1 - Heating regulator - Google Patents

Abstract

The patent application describes a heating regulator for hot-water heating systems operated by a circulating pump, in which the circulating pump runs in constant operation. The regulator not only keeps the room temperature constant at a preselected value but also detects all heat-loss changes of the heating installation in the same way as additional heat supplies, for example by solar radiation, without responding to short-term excessive fluctuations. The regulator is suitable for all heating systems, in particular also for floor-heating and ceiling-heating systems, and for oil-firing, heat-pump and solar-collector heating systems and combined and hybrid systems.

Description

Patent application

Heating controller The invention relates to a heating controller for warm water space heaters.

The conventional control devices regulate the heating system not in the actual sense, but they only limit the room temperature, '' by reducing the heat transfer from the heat generator to the radiators when the temperature falls below the limit switch on the target room temperature and when the target temperature is reached or exceeded switch off. Because the boiler is operated with a minimum temperature when oil heating is in operation must be, a mixing valve is installed in the boiler flow, with which each flow temperature is adjustable, and a circulation pump is provided, which is activated by the room thermostat and is switched off.

The setting of the flow temperature on the mixer valve to a value which ensures that the 'desired' room temperature is reached is an empirical one Matter = matter. If the setting is too low, the circulation pump runs continuously; this does not mean, however, that the heat demand is covered. is; the room thermometer would have to do this to be checked. Switches the circulation pump in more or less long intervals off and on again, then this is an indication that the specified room temperature is achieved.

The control of the mixing valve setting by an outside temperature sensor is only effective to a limited extent because the changes in heat demand correspond to changes in the outside temperature follow only with a considerable delay, and fast Changes, such as strong wind or sunlight from the outside temperature measurement cannot be detected.

With particularly sluggish systems, such as underfloor or ceiling heating the room thermostat-controlled circulation pump is also not applicable; 'here the circulation pump must run continuously.

The invention is based on the object of providing a universally applicable To create a heating controller that constantly supplies heat to the radiators and automatically the actual instantaneous heat demand to achieve and maintain adapts to a given room temperature, and for this purpose continuously the entire Instantaneous heat loss is recorded regardless of the outside temperature.

This is to ensure that the heating system is as efficient as possible and can be operated continuously without any manual operation Adjustment or readjustment measures are required.

According to the invention is one of the temperature difference between one Room temperature sensor and a temperature setpoint = controller-controlled integration controller with variable integration time for a set return temperature, a return temperature sensor, and a heating controller controlled by the difference between the two return temperatures intended.

So only two temperatures are continuously monitored and in one permanently earthed 'control loop processed.

As a result of the feedback of the return temperature with the living space temperature real changes in heat demand are recognized and corrected immediately, at the same time the optimal return temperature is adjusted. The circulation pump is operated continuously; caused by switching the circulation pump on and off Temperature fluctuations therefore do not apply and do not need additional adjustment to become.

In a further embodiment of the invention, comparators are used for comparison the output from an A / D converter digital values of the room temperature sensor with the digital values of the room setpoint temperature coding switch provided for each decimal place a "+" =, "=" - or "#" - and a "-" - signal. An oscilator with different clock frequencies is connected to the logic by a '= "," # "Outputs of the comparators are connected in such a way that the clock signals with the different clock = frequency assigned to the individual comparators output while another logic, with the "+" and "-" outputs of the comparators is connected, the sign of the counting pulses to a B-bit and down counter forwarded clock signals. The reading of the counter. Is the digital return target temperature, which is converted into analog values by a D / 8 converter of the return temperature sensor can be converted, whereupon the difference of both temperatures the rule impulse for the actual heating controller, for example the mixing valve, is derived.

This can be done in such a way that a subtracter, which the Temperature difference is determined and a positive or negative pulse is generated, triggers a monostable multivibrator whose positive or negative output signal duration is set so that the motorized three-way mixer drive for a specific Fraction.

its entire adjustment range is switched on.

In the drawings, several embodiments are in simplified form Block diagrams shown. 1 shows a heating control system in detail conventional type, Fig. 2 the modification of this scheme according to the invention, Fig. 3 the complete room temperature sensor with the 'counting pulse generation, and Fig. 4 the complete return temperature sensor with counter and control of the mixer.

With the usual simple heating control according to Fig. 1 is a circulation pump in the boiler 1, flow 2, heater 3, return 4 circuit 5 is used, which is switched on and off via a room thermostat 6. the The boiler temperature is determined by a thermostat B, depending on the fire kept constant at a minimum value. When the boiler output is not required to the full is, the circulation pump 5 switches off and in larger or smaller intervals a. In order to avoid the constant temperature fluctuations caused by this, continuous operation of the circulating pump was strived for by the fact that the flow temperature has been adapted to the heat demand; for this purpose, a mixing valve was installed in heating line 2 til 9 installed and connected to the return 4 by a short-circuit line 10. Both the manual Verstel development of the mixing valve 9, as well as that of an external device = temperature sensor 11 and a controller 12 controlled motor =.

adjustment 13 was purely empirical.

Such empirical evidence is avoided in the controller according to the invention. According to Fig. 2, the room thermostat 6 is replaced by a temperature sensor -14, and another Tem = temperature sensor 15 is inserted in the return 4. The room temperature setpoint is entered by means of a.CQdierschal = age 16; this can itself in the heated room be attached or, for example, be integrated in 'the controller near the boiler The electronic temperature sensors with integrated sensors provide output voltage genes of 10 mV / k. The voltages of the room temperature sensor 14 are through the A / D converter 17 converted into binary numbers.

The measuring range is between 100C and 25 ° C, so it includes 150/100 and can be represented by a B-digit binary number. The room temperature is through the coding switch 16 is also expressed by an 8-digit binary number. Both Binary numbers are compared by the comparator 15; only the Direction of a deviation. The logic 19 in connection with the oscillator 20 generated Counting pulses for the up / down counter 21 .with a certain frequency and with the sign determined by the comparator 18. At temperature = equality between the setpoint switch 16 and the temperature sensor 14 is the pulse train under = break.

The digital status of the counter 21 represents the return setpoint temperature. It is converted by the D / A converter 22 into analog voltage values that are directly linked to the output voltages of the electronic temperature sensor 15 thereby the comparator 23 can be compared.

If the comparator detects 23 deviations, the counting pulses of the oscillator 20 at the same time also in 'switching step pulses for the servomotor.13 of the mixer 9 implemented and thereby the flow temperature changed step by step, This control process comes to a standstill when the room temperature reaches its setpoint has reached. It only starts again when the heat demand changes. that is, room and return temperatures deviate from their setpoints.

The integration time of the controller must take into account the inertia of the heating system be adapted so that the return temperature can be adjusted to its setpoint without constant oscillation of the mixer adjustment is achieved. Is the pulse frequency at 12 seconds, the integration time for the full range is 150. Tenth of a degree 30 minutes.

The three-way mixer 9 enables the Setting of each flow temperature between the return temperature and the boiler temperature, so between about 300C and BOOT. The invention can of course with any other Flow temperature adjustment are brought into connection, but mostly only have a smaller adjustment range.

In the arrangement according to FIG. 3, the room temperature = temperature sensor 24 measured temperature by the A / D converter 25 in the Aiken code into three digital Decades (tens, ones and tenths of a ° C) broken down and three comparators 26, 27, 28 which in turn are connected to three coding decades 29, 30, 31 in the same code are. The ', actual and target values of each decade are slao compared with each other, both on agreement and importance agreement, as well as on deviation down or up. The equal = / unequal signal at each of the outputs a, b, c is fed to the logic 32 and resolves the exhaust gases of a pulse train in the event of an inequality by the oscillator 33 from The pulse = frequency is different for each output a, b, c. The comparator 26 is, for example, the sequence 12 s, the comparator 27 the sequence 24 s and the comparator 28 is assigned the sequence 48 s. The advance of the unequal = signals are on lines d, e, f or g, h, i; they are inverted by the Logic 34 and open one of the two power gates 35, 36 (and gates) for the om Oszilla = gate 33 impulses to come. These pulses come in as up or down counting pulses the 8-bit counter 37 (Fig. 4).

The counter reading is converted into an analog voltage by the D / A converter 3B converted in the subtracter 39 with the analog voltage of the temperature sensor 40 of the return run is compared; the purpose of this is to prevent positive impulses let through, if the return temperature is above the target temperature, and vice versa.

The impulses reach a monostable multivibrator as trigger impulses 41, which activates the drive with each triggering by a pulse of a defined duration of the mixer 42 by one 'step forwards or backwards', depending on the Sign of the trigger pulse.

This version results in faster integration; further overflowing and commuting is avoided and there is the possibility of using digitally display the room temperature in the boiler room with little effort.

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Claims (7)

Claims 1. Heating controller for circulation pump-operated hot water = water heaters characterized by one according to the temperature difference between a room temperature sensor (14, 24) and a room temperature setpoint adjuster (16; 29, 30, 31) step and direction = switchable actuator (21, 22; 37,. 38 .) for the return set temperature, a return temperature sensor (15, 40), and a self-adjusting comparator (Z3, 39) for) -for stepwise and directional Tracking of the heating or flow temperature controller (9, 13; 41, 42). 2. Heating controller according to claim 1, characterized by an AD converter (17, 25) to convert the analog display of the room temperature sensor (14, 24 ) into a binary number, the formation of the room temperature setpoint = adjuster (16; 29, 30 31) as a coding switch, a comparator (15; 26, 27, 25) for forming the difference of the two binary numbers, and a logic (19, 34) in connection with an oscillator (20, 33), which corresponds to the difference positive or negative counting pulse = se'an.a memory counter (21, 37), the status of which is the set return temperature reproduces. 3. Heating controller according to claim 2, characterized by a D / A converter (22'-) for conversion. of the digital counter reading into one with that of the return tempe = temperature sensor (15) comparable signal, and a Com = parator '(23, 39), the if the signals are not identical, the signal originating from the room temperature variable as a signal for the forward or backward adjustment of the tempera = turntable (9, 13; 41, 42) releases. 4 heating controller according to claim 1 to 3, characterized by a A / D-ian, dler (25) in connection with several decimally graduated comparators (26, 27, Z8) and coding switches (29, 30, 31) 5. Heating controller according to claim 4, characterized in that the outputs of the comparators (26, 27, 25) with a logic (39) are connected, which the positive outputs to an AND gate (35 ') undidis negative outputs to an AND gate. (36) and that the "=" and "g 'outputs of the comparators are fed to a Logi'k (32), which at "g", the counting pulses of the oscillator (33) are fed to the gates (35, 36) and 'enable the pending counting signal. 6. Heating controller according to claim 5, characterized in that ennzeich = net that each comparator (26, 27, 28) is assigned a different pulse frequency is, in such a way that the comparator (26) the frequency f, the comparator (27 ) the frequency 2.f and the comparator (.28) the frequency 4.f. 7. Heating controller according to one of claims 2 to 6; da = marked by, that an 8th bit up and down counter is provided as a memory counter (21, 37). -8. Heating controller according to one of claims 1 to 7, marked = characterized by one of the Switching pulse generator (37, 39) downstream pulse-triggered monostable 'Multi vibrator (41.), the output signal length of which is chosen so that the downstream Three-way mixer drive or temperature control drive (13, 42) for a fixed = standing fraction of its total gain range is switched.