WO2009072759A2

WO2009072759A2 - Method for controlling heating system

Info

Publication number: WO2009072759A2
Application number: PCT/KR2008/006791
Authority: WO
Inventors: Si-Hwan Kim
Original assignee: Kyungdong Network Co., Ltd.
Priority date: 2007-12-04
Filing date: 2008-11-18
Publication date: 2009-06-11
Also published as: CN101889174A; US20100270385A1; WO2009072759A3; EP2225496A2; KR100924147B1; CN101889174B; EP2225496A4; KR20090058051A

Abstract

Provided is a method for controlling a heating system capable of organically controlling heating of respective rooms to uniformly heat the respective rooms by proportionally calculating heat supplies required by the respective rooms from a temperature of returned water, even when the heat supplies required by the respective rooms are different from each other depending on external conditions of the respective rooms. The method for controlling a heating system adjusts flow rates of heating water supplied into the respective rooms by adjusting opening rates of a plurality of room valves installed on heating water pipes, characterized in that a temperature of the returned heating water is measured, a ratio of opening rates of the respective room valves is calculated from the measured temperature of the returned water to proportionally supply heat into the respective rooms, and the opening rates of the respective room valves are adjusted depending on the calculated ratio of the opening rates.

Description

METHOD FOR CONTROLLING HEATING SYSTEM

Technical Field

[1] The present invention relates to a method for controlling a heating system, and more particularly, to a method for controlling a heating system capable of adjusting a flow rate of heating water depending on heating requirements of the respective rooms to evenly heat the respective rooms. Background Art

[2] Generally, a boiler system includes a warm water distributor for distributing heating water to the respective rooms to be heated. The warm water distributor receives water heated by a heat exchanger of a boiler through a heating water supply pipe to supply the heated water to the respective rooms. The supplied water transmits heat energy to the respective rooms and then is cooled, and conveyed to a heating water return pipe. The warm water distributor includes room valves for adjusting a flow rate of heating water supplied into the respective rooms.

[3] The room valves are classified into an ON/OFF type, a constant flow rate type, and a proportional control type depending on control methods.

[4] FIG. 1 is a schematic view of a heating system including ON/OFF valves and constant flow rate valves.

[5] The ON/OFF valves 41 are installed at a distributor 40 where heating water supplied from a heat source 10 is returned after passing through the respective rooms 30, to block the valves 41 to stop supply of the heating water when a room temperature arrives at a temperature set by a user, and to open the valves 41 to supply the heating water when the room temperature is lower than the temperature set by a user.

[6] The constant flow rate valves 21 are installed at a distributor 20 where heating water is generally supplied, to prevent the heating water from flowing therethrough at more than a set flow rate. When heating water from a single heat source 10 is supplied into a plurality of rooms 30, different piping lengths of the respective rooms 30 cause arrival times at the set temperatures of the respective rooms 30 to vary. Therefore, in order to solve problems of irregular heating conditions, the constant flow/rate valves 21 are installed at the respective pipes connected to the respective rooms 30 to uniformize the arrival times at the set temperatures of the respective rooms 30.

[7] The constant flow rate valves 21 have advantages of reducing the entire length of the heating pipes, reducing the number of distributors, and solving problems related to irregular heating, and thus, have been used for various heating systems.

[8] However, since the flow rate of the constant flow rate valves 21 are set by a con- struction company depending on the length and diameter of the constant flow rate valves 21, it is impossible for a user to arbitrarily vary a flow rate of the valves 21 once set by the company. Therefore, when the length of the heating pipes is varied by remodeling, extension of balcony, or the like, heating irregularity may occur again.

[9] In addition, heat supplies required by the respective rooms 30 are determined by positions of the respective rooms 30 (whether the rooms 30 have a good supply of sunlight), insulation of the respective rooms 30, external conditions such as an external temperature, and so on, in addition to the length of the pipes. As a result, heat supplies required for the respective rooms 30 to uniformly heat the rooms 30 may be different from each other. However, since the constant flow rate valves 21 are manually adjusted, it is impossible to adjust the flow rate of the valves 21 depending on actual states of the rooms 30.

[10] Therefore, in order to solve the problems of the constant flow rate valve 41, a proportional control valve has been developed.

[11] FIG. 2 is a schematic view of a heating system having proportional control valves.

[12] The proportional control valves 42 are installed at a distributor 40a where heating water supplied from a heat source 10 is returned after passing through the respective rooms 30, to adjust a flow rate of heating water to provide a comfortable indoor environment according to the set temperature of each respective room. Reference numeral 20a is a distributor in which heating water is supplied.

[13] The conventional proportional control valve receives flow rate data fed back from a flow sensor to adjust an opening rate of the valve to adjust a supply amount of the heating water. However, since there are many foreign substances in the heating water, the flow sensor may be contaminated.

[14] In addition, when the flow sensor is not used, as shown in FIG. 2, a proportional-in- tegrated-derivative (PID) control method is used. Temperature sensors 43 measure a temperature of returned heating water, and the measured temperature of the returned water is fed back to the temperature sensors 43. The temperature sensors 43 calculate deviation between a target temperature and the current temperature to provide a control amount in proportion to the deviation until the temperature arrives at the target temperature. That is, the PID control method includes calculating the deviation between the target temperature and the current temperature, adjusting an opening rate of the valves 42 in proportion to the deviation, and measuring variation in the temperature of the returned water to re-adjust the opening rate of the valve, wherein a flow rate of the valves 42 is adjusted through repeated adjustments of the opening rate of the valves 42 until the temperature arrives at the target temperature.

[15] Since the temperature of the returned heating water is a temperature after passing through the pipes installed in the respective rooms, the temperature becomes the best information for determining heat supplies required by the respective rooms 30. However, response characteristics are too slow to uniformly control heating of the respective rooms 30.

[16] That is, when the flow rate is adjusted by adjusting an opening rate of the proportional control valve 42, the adjusted flow rate affects the temperature of the returned heating water, which is time consuming, and thus, it is impossible to instantly determine whether the adjusted flow rate is appropriate. In addition, since the rooms 30 are independently controlled by the valves 42, respectively, variation in flow rate of one room affects another room, and thus, it is substantially impossible to organically control the flow rate of the respective rooms 30 due to the slow response characteristics.

[17] Therefore, the conventional proportional control method cannot uniformly control heating of the respective rooms 30, and the conventional PID control method increases the number of operations of the proportional control valves, reducing durability of the valves.

Disclosure of Invention

Technical Problem

[18] In order to solve the foregoing and/or other problems, it is an aspect of the present invention to provide a method for controlling a heating system capable of organically controlling heating of respective rooms to uniformly heat the respective rooms and reducing the number of operations of proportional control valves by proportionally calculating heat supplies required by the respective rooms from a temperature of returned water, even when the heat supplies required by the respective rooms are different from each other due to external conditions of the respective rooms. Technical Solution

[19] One aspect of the present invention provides a method for controlling a heating system that adjusts flow rates of heating water supplied into the respective rooms by adjusting opening rates of a plurality of room valves installed on heating water pipes, characterized in that a temperature of the returned heating water is measured, a ratio of opening rates of the respective room valves is calculated from the measured temperature of the returned water to proportionally supply heat into the respective rooms, and the opening rates of the respective room valves are adjusted depending on the calculated ratio of the opening rates.

[20] In this case, the temperature information of the returned water may be an arrival time needed to arrive at a predetermined temperature, and the ratio of the opening rates of the respective room valves may be determined by a ratio of the arrival times.

[21] In addition, the ratio of the opening rates of the respective room valves may be set such that an opening rate of the room valve having the longest arrival time is set as a maximum rate, and opening rates of the other room valves are proportionally set with respect to the maximum rate to be reduced as the arrival times are reduced. [22] Further, when the ratio of the opening rates of the respective room valves is set, target voltages of positions of linear magnets of the respective rooms may be set depending on the ratio of the opening rates, and the positions of the linear magnets may be varied to adjust the opening rates until arrival at the target voltages.

Advantageous Effects

[23] In accordance with a method of controlling a heating system in accordance with the present invention, heat supplies required by respective rooms may be determined on the basis of a temperature of returned water reflecting actual environmental conditions of the respective rooms, and thereby flow rates supplied into the respective rooms may be adjusted to uniformly heat the respective rooms and provide a comfortable indoor environment. Brief Description of the Drawings

[24] The above and other objects, features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:

[25] FIG. 1 is a schematic view of a heating system including an ON/OFF valve and a constant flow rate valve;

[26] FIG. 2 is a schematic view of a heating system including proportional control valves;

[27] FIG. 3 is a block diagram of a heating system employing a control method in accordance with the present invention;

[28] FIG. 4 is a cross-sectional view of each of room valves adapted to a heating system in accordance with an exemplary embodiment of the present invention;

[29] FIG. 5 is a schematic view of a linear magnet adapted to FIG. 4;

[30] FIG. 6 is a graph showing arrival times at set temperatures of returned water of the respective rooms; and

[31] FIG. 7 is a flowchart showing a method for controlling a heating system in accordance with an exemplary embodiment of the present invention. Best Mode for Carrying Out the Invention

[32] Exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[33] FIG. 3 is a block diagram of a heating system employing a control method in accordance with the present invention, FIG. 4 is a cross-sectional view of each of room valves adapted to a heating system in accordance with an exemplary embodiment of the present invention, and FIG. 5 is a schematic view of a linear magnet adapted to FIG. 4.

[34] Basic constitution of the heating system in accordance with the present invention is similar to that of FIG. 2. That is, as shown in FIG. 3, the heating system includes returned water temperature sensors 100 for detecting a temperature of returned water passing through the respective rooms, the respective room valves 300 installed at heating pipes through which the returned water passes to adjust a flow rate of heating water, and a controller 200 for receiving temperature data detected by the returned water temperature sensors 100 to adjust opening rates of the respective room valves 300.

[35] An example of the room valve 300 adapted to the present invention will be described with reference to FIG. 4.

[36] The room valve 300 includes a motor (not shown) rotated by alternate current in one direction, a cam member 322 eccentrically connected to a shaft 321 of the motor, and a valve part 345 reciprocated along a profile of an outer periphery of the cam member 322 to adjust an opening rate of a heating water flow path when the motor shaft 321 is rotated.

[37] A cam contact member 331 is resiliently supported at a lower surface of the cam member 322 by a spring 332. The cam contact member 331 is inserted into an upper guide member 333 to be guided by the upper guide member 333 upon vertical movement thereof. A shaft contact member 334 is inserted into an inner lower part of the upper guide member 333. A lower end of the spring 332 is in contact with an upper surface of the shaft contact member 334, and a center of a concaved lower surface of the shaft contact member 334 is in contact with an upper end of a shaft 341.

[38] The shaft 341 passes through a center of a rotary lock member 344 coupled to an inside of a lower guide member 343, and has a lower end coupled to a valve part 345. A spring 342 is fitted onto an outside of the shaft 341 to be pressed upon lowering of the shaft 341. The valve part 345 opens and closes an opening 353 formed between an inlet 351 and an outlet 352 of a heating water flow path, and a vertical position thereof is varied with the shaft 341.

[39] Meanwhile, a linear magnet 311 is installed to be resiliently supported by the spring

312 and to be always in contact with an outer surface of the cam member 322 upon rotation of the cam member 322, and a vertical position of the linear magnet 311 is varied along a cam profile of the cam member 322. A magnetic sensor (not shown) and a printed circuit board (not shown) are installed at a position adjacent to the linear magnet 311 to detect magnetic flux varied upon variation in position of the linear magnet 311 to control rotation of the motor.

[40] Here, the linear magnet means a magnet that represents straightness (linearity) of variation in magnetic flux depending on displacement. Hereinafter, the linear magnet 311 and the magnetic sensor will be described.

[41] The linear magnet 311 shown in FIG. 5 is disclosed in Korean Patent Registration

No. 660564.

[42] Referring to FIG. 5, an N polarity and an S polarity are magnetized at the linear magnet 311 from a left upper corner of a rectangular shape in a diagonal direction in a sine shape.

[43] In general, it is known that magnetic flux is in reverse proportion to a square distance. Therefore, in the case of a general magnet, variation in magnitude of a magnet depending on displacement has no linearity of a secondary function graph.

[44] On the other hand, as shown in FIG. 5, in the linear magnet 311 adapted to the present invention, while there is no linearity of magnetic flux of the N polarity depending on displacement when the magnet is magnetized in a diagonal direction as shown in a dotted line, the magnetic flux depending on the displacement represents linearity when the magnet is magnetized in a sine shape in a diagonal direction as shown in a solid line.

[45] The magnetic sensor for detecting variation in magnetic flux depending on variation in position of the linear magnet 311 of FIG. 5 detects the variation in magnetic flux over sections 0 to 12 of the magnet 311. A polar surface of the linear magnet 311 is spaced apart a predetermined distance d from the magnetic sensor and the linear magnet 311 moves in a direction perpendicular to a polar axis and parallel to the polar surface. In this case, among the sections 1 to 12, all but the outermost non-linear sections, i.e. sections 2 to 10, may be employed as use sections.

[46] The magnetic sensor used to measure variation in magnetic flux depending on position variation of the linear magnet 311 may be a hall sensor (programmable hall IC) widely used as a method of detecting a magnetic field. Operation of the hall sensor generates electric potential perpendicular to a current direction and a magnetic field direction when current is flowed to an electrode of a semiconductor (hall device) to apply a magnetic flux, and thus, it is possible to detect variation in position of the linear magnet 311 from the electric potential.

[47] While the method using the linear magnet as a non-contact type has been described, the method using a variable resistor and a variable inductance, instead of the linear magnet and the magnetic sensor, may be provided.

[48] When the variable resistor is used, an output voltage of the variable resistor depending on an opening rate of the valve part 345 is preset, and when a contact position of the variable resistor is varied depending on rotation of the motor, it is possible to detect the opening rate on the basis of the output voltage depending on the variation.

[49] In addition, when the variable inductance is used, an output voltage of the variable inductance depending on an opening rate of the valve part 345 is preset, and when a position of the magnet in a coil is varied depending on rotation of the motor, it is possible to detect the opening rate of the valve part 345 from the output voltage depending on the variation.

[50] Hereinafter, a control method in accordance with the present invention will be described.

[51] FIG. 6 is a graph showing arrival times at set temperatures of returned water of the respective rooms, and FIG. 7 is a flowchart showing a method for controlling a heating system in accordance with an exemplary embodiment of the present invention.

[52] When heating is started, a returned water temperature sensor 100 measures a temperature of returned water (S410).

[53] Heat supplies required by respective rooms are different from each other depending on supply of sunlight, insulation, and so on. In addition, the temperature of the returned water is measured after the heating water passes through the respective rooms and then heat thereof is radiated. Therefore, the temperature of the returned water is an important reference that can determine heat supplies required by the respective rooms.

[54] When the temperature of the returned water is measured, it is determined whether the temperature of the returned water arrives at a predetermined set temperature Tset (S420). Here, the set temperature Tset is an arbitrary value, which may be set as an appropriate temperature lower than a temperature of supplied water Tsup.

[55] When it is determined that the temperature of the returned water arrives at the set temperature Tset, an arrival time at the set temperature Tset of the returned water temperature is calculated (S430). For example, as shown in the graph of set temperature arrival times of FIG. 6, an arrival time at the set temperature Tset of a third room is the fastest time tl, an arrival time at the set temperature Tset of a first room is t2, an arrival time at the set temperature Tset of a second room is t3, and an arrival time at the set temperature Tset of a living room is the latest time t4,

[56] When the arrival times at the set temperatures of the returned water temperature are calculated, a ratio of opening rates of the respective room valves 300 is calculated (S440).

[57] The above process will be described with reference to the following table 1.

[58] Table 1 [Table 1] [Table ]

[59] That is, calculating ratios of arrival times of the respective rooms with reference to the arrival time (24 minutes as 100%) at the set temperatures Tset of the living room, which is the latest time among the measured temperatures of the returned water, the ratios as described above are calculated.

[60] This means that the living room requires the largest heat supply, the fastest arrival time at the set temperature requires a small heat supply, and the latest arrival time at the set temperature requires a large heat supply.

[61] Therefore, a ratio of the arrival times at the set temperatures from the measured temperatures of the returned water is calculated. Since the calculated ratio of the arrival times at the set temperatures means a ratio of heat supplies required by the respective rooms, the ratio may be defined as a ratio of opening rates of the respective room valves 300.

[62] Eventually, as described in the above table 1, the room valve 300 installed at a heating pipe of the living room is fully opened (100%), the room valve 300 of the first room is opened by 33%, the room valve 300 of the second room is opened by 42%, and the room valve 300 of the third room is opened by 25% (S450).

[63] Hereinafter, a process of adjusting an opening rate of the respective room valves will be described.

[64] When the opening rates of the respective room valves 300 are set, the controller 200 rotates the motors of the respective room valves 300.

[65] The controller 200 has a program in which correlation between variation in opening rates of the respective room valves and detected voltages are preset.

[66] That is, when the valve part 345 is maximally opened, a voltage at a position of the linear magnet 311 is set as, for example, 4.5V, and when the valve part 345 is entirely closed, a voltage at a position of the linear magnet 311 is set as, for example, 0.5V, wherein values therebetween are represented as a straight section due to linearity of the linear magnet 311 (i.e., a proportional relationship is provided).

[67] Therefore, the controller 200 sets a target voltage of the opening rates of the valve part 345 from the proportional relationship, and rotates the motor to move the valve part 345 to thereby adjust the opening rate. [68] In this case, since the cam member 322 is rotated with the motor, the linear magnet

311 is raised along a profile of an outer periphery of the cam member 322. When electric potential generated from the magnetic sensor depending on variation in position of the linear magnet arrives at the target voltage, the controller determines that the opening rate arrives at the target opening rate, and stops operation of the motor.

[69] Therefore, the controller can set opening rates of the respective room valves 300 to uniformly heat the rooms in consideration of pipe lengths of the rooms and external conditions affecting temperature requirements of the rooms (the supply of sunlight, insulation, external temperatures, and so on).

[70] As described above, in a state in which the opening rates of the respective room valves 300 are set, a user can adjust a room controller to heat the rooms depending on temperatures set by the room controller. That is, when a room temperature exceeds the temperature set by the user, the room valve 300 is closed to stop the heating, and when the temperature is lower than the temperature set by the user, the room valve 300 is opened by the opening rate corresponding to the ratio set as described above to repeat the heating process.

[71] According to the above method, since the opening rate can be adjusted by only one operation until a voltage arrives at the target voltage set by the position of the linear magnet of the room valve, it is possible to reduce the number of operations of the room valve to improve durability of the room valve.

[72] While few exemplary embodiments of the room valve 300 having the linear magnet

311 the present invention have been shown and described to adjust an opening rate of the room valve 300, it will be appreciated by those skilled in the art that various changes may be made to these embodiments without departing from the spirit and scope of the invention as defined by the appended claims and their equivalents.

[73]

Industrial Applicability

[74] As can be seen from the foregoing, a method for controlling a heating system in accordance with the present invention can uniformly heat rooms even when heat supplies required by the rooms are different from each other, and reduce the number of operations of a proportional control valve.

[75]

Claims

[1] A method for controlling a heating system that adjusts flow rates of heating water supplied into the respective rooms by adjusting opening rates of a plurality of room valves installed on heating water pipes, characterized in that a temperature of the returned heating water is measured, a ratio of opening rates of the respective room valves is calculated from the measured temperature of the returned water to proportionally supply heat into the respective rooms, and the opening rates of the respective room valves are adjusted depending on the calculated ratio of the opening rates.

[2] The method according to claim 1, wherein the temperature information of the returned water is an arrival time needed to arrive at a predetermined temperature, and the ratio of the opening rates of the respective room valves is determined by a ratio of the arrival times.

[3] The method according to claim 2, wherein the ratio of the opening rates of the respective room valves is set such that an opening rate of the room valve having the longest arrival time is set as a maximum opening rate, and opening rates of the other room valves are proportionally set with respect to the maximum opening rate to be reduced as the arrival times are reduced.

[4] The method according to any one of claims 1 to 3, wherein, when the ratio of the opening rates of the respective room valves is set, target voltages of positions of linear magnets of the respective rooms are set depending on the ratio of the opening rates, and the positions of the linear magnets are varied to adjust the opening rates until arrival at the target voltages.