JPH08219404A - Control method for multi-can installation system of fluid heater - Google Patents

Abstract

(57) [Summary] [Purpose] In a multi-can installation system for fluid heaters,
The purpose is to prevent heat loss and improve responsiveness to loads. [Constitution] In a multi-can installation system for a fluid heater, which controls the operating number of a plurality of fluid heaters 1 installed in parallel according to the situation of a load 2 in accordance with a preset priority order, depending on the situation of the load 2. The operation permission signal is output to the required number of fluid heaters 1, and the combustion and the combustion standby of the fluid heater 1 receiving the operation permission signal are controlled according to the heating state of the fluid inside the fluid heater 1. , While in the combustion standby state, the pilot combustion state is maintained, and when a combustion request is made, the state is immediately shifted to the main combustion state, and the fluid heater 1 in which the ignition error or the midway extinction occurred within the predetermined time in the past changes to the lower order However, do not maintain the pilot combustion state while waiting for combustion.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention installs a plurality of fluid heaters such as a hot water boiler, a steam boiler, a heat medium boiler, a heat exchanger, an absorption refrigerator, etc. in parallel, depending on the load condition. The present invention relates to a multi-can installation system that automatically controls the number of operating fluid heaters.

[0002]

2. Description of the Related Art As is well known, a multi-can installation system for boilers has been implemented in which a plurality of boilers are installed in parallel and the number of operating boilers is automatically controlled according to the load condition. . This multi-can installation system for boilers has a remarkable effect on energy saving because each boiler can be operated with high efficiency compared to installing one large-capacity boiler. It has the advantage of excellent responsiveness. Normally, at the time of starting the boiler, the pre-purge operation is performed so that the unburned residual gas does not remain by any chance, and then the ignition operation is performed. This pre-purge operation is necessary in consideration of safety, but on the other hand, it causes heat loss and response delay.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to prevent heat loss and improve responsiveness to a load in a multi-can installation system for a fluid heater.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and controls the operating number of a plurality of fluid heaters installed in parallel according to a load condition according to a preset priority order. In the multi-can installation system of the fluid heater, the operation permission signal is output to the required number of fluid heaters according to the load condition, and the combustion and the combustion standby of the fluid heater receiving the operation permission signal are performed. It controls according to the heating state of the fluid inside the fluid heater, maintains the pilot combustion state while waiting for the combustion, and immediately shifts to the main combustion state when there is a combustion request, and the ignition error or midway in the past within a predetermined time The fluid heater in which the quenching has occurred is characterized in that the priority is changed to the lower order and the pilot combustion state is not maintained during the combustion standby.

[0005]

The number of operating fluid heaters installed in parallel is controlled according to the load condition in accordance with the preset priority order, and the operation permission signal is output to the required number of fluid heaters. The fluid heater receiving the operation permission signal controls its combustion and combustion standby according to the heating state of the fluid inside the fluid heater, and maintains the pilot combustion state during the combustion standby, and the combustion request When there is, it immediately shifts to the main combustion state. In addition, the fluid heater in which the ignition error or the extinction of flame occurred in the past predetermined time,
Change the priority to lower so that the pilot combustion state is not maintained while waiting for combustion.

[0006]

The preferred embodiments of the present invention will be described below. In the embodiment shown in FIG. 1, a hot water boiler is installed as the fluid heater 1. In the figure, a plurality of fluid heaters 1 are installed in parallel, these fluid heaters 1 and loads 2 are connected by a fluid supply path 3 and a fluid return path 4, and the number of operating fluid heaters 1 is The load 2 is controlled according to the situation. A circulation pump 5 is inserted in the fluid return path 4. This circulation pump 5
May be inserted into the fluid supply path 3.
The fluid supply path 3 is provided with a temperature detector 6 for detecting the supply temperature T of the fluid. Based on the signal from the temperature detector 6, the number of operating fluid heaters 1 is controlled by the controller 7 according to a preset control procedure. That is, when the fluid supply temperature T is high, the number of operating fluid heaters 1 is reduced, and when the fluid supply temperature T is low, the operating number of fluid heaters 1 is increased. Although the temperature sensor 6 is mounted on the fluid supply path 3 in the illustrated embodiment, the fluid return path 4 is provided.
Can also be provided. Priorities are set in advance for the fluid heaters 1, and the operation of each fluid heater 1 is controlled in accordance with the priorities. As for the priority, rotation is appropriately performed so that the operating time of each fluid heater is averaged.

The controller 7 outputs an operation permission signal to the required number of fluid heaters 1 based on the signal from the temperature detector 6. Fluid heater 1 that received the operation permission signal
Starts operation, but the combustion of the fluid heater 1 is turned on-
The OFF state is controlled for each fluid heater according to the heating state of the fluid inside thereof, and combustion and combustion standby are alternately repeated. Normally, when the combustion is started, the control is performed in the order of combustion standby → pre-purge → ignition try → pilot combustion → main combustion, and when combustion is stopped, main combustion → post-purge → combustion standby is controlled in this order.

The fluid heater 1 comprises a pilot burner and a main burner. While the combustion is waiting, the pilot burner is continuously burned without completely stopping the combustion, and the main burner can be immediately ignited when a combustion request is made. This is to maintain the so-called idling state. That is, the control device 7 has a function of outputting a pilot combustion state maintaining signal to the one of the fluid heaters 1 in the combustion standby state in which the operation permission signal is received, and the above-mentioned combustion is performed. In the cycle, the pre-purge and the post-purge are omitted, the pilot combustion state is maintained during the combustion standby, and the main combustion state is immediately set when the combustion request is made.
By omitting the prepurge time, the heat loss corresponding to the time is reduced and the response time to the combustion request is significantly shortened. Also, since the number of ignitions is reduced,
The life of the ignition device, etc. is significantly extended.

FIG. 2 shows an example of control of each fluid heater when four fluid heaters are installed. Of the four fluid heaters, the operation permission signal is output to the three fluid heaters No. 1 to No. 3, and the operation stop signal is output to the fluid heater No. 4. Is in a state of The combustion of the No. 1 to No. 3 fluid heaters that have received the operation permission signal is ON / OFF controlled according to the heating state of the fluid inside each fluid heater. Of these, No. 1 and No. 2
The pilot combustion state maintenance signal is output to the fluid heater of. It is possible to output the pilot combustion state maintenance signal to the No. 3 fluid heater, but for those with a long combustion standby time, the need to output the pilot combustion state maintenance signal is relatively low. Therefore, the pilot combustion state maintaining signal is not output to such a fluid heater. Therefore, the fluid heater that sends the pilot combustion state maintenance signal is selected according to its needs. That is, m units are selected in descending order of priority with respect to the total number M of installed fluid heaters 1,
When the engine receives the operation permission signal, the pilot combustion state is maintained during the combustion standby state, and when the combustion request is made, the state is immediately shifted to the main combustion state. By doing so, it is possible to prevent excessive consumption of fuel while ensuring quick response to a load, and to achieve a great effect on energy saving. The m units are preferably set to M / 2 or less.

As shown in FIG. 3, the fluid heater 1 in which the ignition error or the midway extinction has occurred within a predetermined time period (for example, within 24 hours) in the past, has its priority changed to the lower order and the pilot combustion state is set during the combustion standby. Try not to keep on. When m fluid-heaters 1 are selected in descending order of priority with respect to the total number M of installed fluid-heaters 1 and these fluid-heaters 1 receive an operation permission signal, they are maintained in the pilot combustion state during combustion standby and burned. When it is set to immediately shift to the main combustion state when a request is made, among the m fluid heaters 1, the fluid heater 1 in which an ignition error or midway extinction has occurred within a predetermined time in the past, Change the priority to lower so that the pilot combustion state is not maintained while waiting for combustion. Instead, the m + 1th fluid heater 1 is maintained in the pilot combustion state while waiting for combustion, and is immediately shifted to the main combustion state when a combustion request is made. By doing so, it is possible to avoid the possibility that the multi-can installation system will stop midway (reduce the number of misfires) and to stably supply the heating fluid.

In the embodiment shown in FIG. 3, initially, No. 1
~ No. 4, No. 1, No. 2, No. 3, for 4 fluid heaters
The priorities are set in the order of No. 4, and since the No. 2 fluid heater had an ignition error in the past predetermined time, the No. 2 fluid heater priority was lowered to the No. 1 ， No.3 ， No.4 ，
The priority is changed in the order of No.2. And initially, No.1
If the pilot combustion state maintenance signal is output to the two fluid heaters of No. 2 and No. 2, after changing the priority,
The pilot combustion state maintenance signal is output to the two fluid heaters No. 1 and No. 3, and the pilot combustion state maintenance signal is not output to the fluid heating machine No. 2.

Next, the operation of the above configuration will be described. The fluid heated by the fluid heater 1 is supplied to the load 2 via the fluid supply path 3. The fluid that has supplied a predetermined amount of heat to the load 2 returns to the fluid heater 1 via the fluid return path 4. In this circulation process, a temperature detector 6 provided in the fluid supply path 3 sends a fluid temperature detection signal to the controller 7. Control device 7 that receives the temperature detection signal
Controls the number of operating fluid heaters 1 according to the temperature of the fluid according to a preset program, and outputs an operation permission signal to the required number of fluid heaters 1. The fluid heater 1 that has received the operation permission signal starts operation, and combustion is turned on for each fluid heater according to the heating state of the fluid inside thereof.
-OFF is controlled, and combustion and combustion standby are repeated alternately. By controlling the number of operating fluid heaters 1 installed in multiple units, the ability to follow load fluctuations is improved, and the required number of fluid heaters are always operated with high efficiency without operating unnecessary fluid heaters. can do.

Further, the control device 7 outputs a pilot combustion state maintenance signal to the predetermined number (m) of fluid heaters 1 of the fluid heaters 1 which have received the operation permission signal during combustion standby. It The fluid heater 1 that has received the pilot combustion state maintenance signal maintains the pilot combustion state during the combustion standby state, and when there is a combustion request, skips the pre-purge time and immediately shifts to the main combustion state. By doing so, heat loss is reduced, the responsiveness of the entire system is improved, the number of ignitions is reduced, and the life of each accessory (ignition device, etc.) is significantly extended.

Then, the fluid heater 1 in which the ignition error or the extinguishing of the flame has occurred within the predetermined time in the past is changed to the lower priority so as not to be maintained in the pilot combustion state during the standby for combustion. When m units are selected in descending order of priority with respect to the total number M of installed fluid heaters 1 and the pilot combustion state maintenance signal is output to these m units of fluid heaters 1, Of the m fluid heaters 1, the fluid heater 1 that has an ignition error or midway extinction within the predetermined time period in the past has its priority changed to a lower rank so as not to be maintained in the pilot combustion state during combustion standby. Instead, m +
The first fluid heater 1 is maintained in the pilot combustion state while waiting for combustion, and is immediately shifted to the main combustion state when a combustion request is made. By doing so, it is possible to avoid the possibility that the multi-can installation system will stop midway (reduce the number of misfires) and to stably supply the heating fluid.

In the above embodiment, the case where the hot water boiler is used as the fluid heater 1 has been described.
In addition, a steam boiler, a heat medium boiler, a heat exchanger, an absorption refrigerator, or the like can be used as the fluid heater 1.
For example, when a steam boiler is used as the fluid heater 1, a common steam header is provided for each steam boiler, and according to the pressure in the steam header, the operating number of the steam boiler is reduced if the pressure increases, If the pressure becomes low, the operating number of steam boilers is increased to control the operating number of steam boilers.

[0016]

The present invention has the above-mentioned structure.
In the multi-can installation system of the fluid heater, while controlling the combustion and combustion standby of the fluid heater receiving the operation permission signal according to the heating state of the fluid inside the fluid heater,
During combustion standby, the pilot combustion state is maintained, and when a combustion request is made, the system immediately transitions to the main combustion state, so the pre-purge time is omitted, heat loss is reduced, and the responsiveness of the entire system is reduced. In addition, the number of ignitions is reduced and the life of each accessory (ignition device, etc.) is significantly extended. Also, for fluid heaters that have had a misfiring or extinguished flame during the past predetermined time, the priority is changed to a lower priority so that the multi-can installation system will not be in the pilot combustion state while waiting for combustion. It is possible to avoid the possibility of stopping due to as much as possible, reduce the number of misfires, and stably supply the heating fluid. Then, instead of the fluid heater whose priority has been changed to the lower order, another fluid heater is maintained in the pilot combustion state while waiting for combustion, and when the combustion request is made, it immediately shifts to the main combustion state. It is possible to stably supply the heating fluid while ensuring quick response to the load.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an example of a control method according to the present invention.

FIG. 3 is an explanatory diagram showing an example of priority order change in the control method of the present invention.

[Explanation of symbols]

 1 fluid heater 2 load

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yoshimin Tsubota 7 Horie-cho, Matsuyama-shi, Ehime Prefecture Miura Industrial Co., Ltd. (72) Inventor Keiji Hino Horie-cho, Matsuyama-shi, Ehime 7 Miura Industrial Co., Ltd. (72 ) Inventor Koichi Wakae 7 Horie-cho, Matsuyama-shi, Ehime Miura Industrial Co., Ltd.

Claims (2)

[Claims] 1. A multi-can installation system for a fluid heater, wherein the operating number of a plurality of fluid heaters 1 installed in parallel is controlled according to a situation of a load 2 in accordance with a preset priority order,
The operation permission signal is output to the required number of fluid heaters 1 according to the situation of the load 2, and the combustion and the combustion standby of the fluid heater 1 receiving the operation permission signal are set to A fluid heater that controls according to the heating state, maintains the pilot combustion state while waiting for the combustion, and immediately shifts to the main combustion state when a combustion request is made, and an ignition error or a midway extinction occurred within a predetermined time in the past 1 is
A control method in a multi-can installation system for a fluid heater, characterized in that the priority is changed to a lower level and the pilot combustion state is not maintained during combustion standby. 2. The control method in the multi-can installation system for a fluid heater according to claim 1, wherein m units are selected in descending order of priority with respect to the total number M of installed fluid heaters 1,
When these fluid heaters 1 receive the operation permission signal, they are maintained in the pilot combustion state during the combustion standby state, and immediately when there is a combustion request, they are immediately shifted to the main combustion state. The fluid heating machine 1 which has an ignition failure or a midway flame extinction within a predetermined time in the past has its priority changed to a lower level so as not to be maintained in the pilot combustion state during combustion standby, and the fluid heater m + 1 1. A control method in a multi-can installation system for a fluid heater, characterized in that No. 1 is maintained in a pilot combustion state while waiting for combustion, and when a combustion request is made, the main combustion state is immediately changed.