JPH08219551A - Control method in multi-can installation system of fluid heater - Google Patents

Abstract

PURPOSE: To prevent heat loss and improve response to a load in a multi-can installation system of a fluid heater. CONSTITUTION: A multi-can installation system of a fluid heater is provided which controls the number of operation of a plurality of parallely installed fluid heaters 1 in conformity with a previously set priority and in response to conditions of a load 2. In the multi-can installation system, an operation allowance signal is outputted to the fluid heaters 1 of a necessary number in response to the conditions of the load 2, and combustion and combustion standby of the fluid heater 1 that receives the operation allowance signal are controlled in response to the heating state of a fluid in the fluid heater 1. Together with this, there are selected (m) fluid heaters having a higher priority with respect to the whole number M of installation of the fluid heaters. When these fluid heaters 1 receive the operation allowance signal, the operation is kept at a pilot combustion state during combustion standby while being transferred to a main combustion state immediately after reception of a combustion request.

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. Control is performed according to the heating state of the fluid inside the fluid heater, and m units are selected in descending order of priority with respect to the total number M of installed fluid heaters, and these fluid heaters receive the operation permission signal. When
It is characterized in that the pilot combustion state is maintained during the standby for combustion and the main combustion state is immediately set when a combustion request is made.

[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 operating fluid heaters of this number. When the fluid heater receives the operation permission signal, its combustion and combustion standby are controlled according to the heating state of the fluid inside the fluid heater. Total number of installed fluid heaters M
, M units are selected in descending order of priority, and when these fluid heaters receive the operation permission signal, they are maintained in the pilot combustion state during combustion standby, and immediately when there is a combustion request, the main combustion state Move to.

[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.

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 maintaining signal to a predetermined number (m) of fluid heaters 1 of the fluid heaters 1 that 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.

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.

[0013]

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. Further, m units are selected in descending order of priority with respect to the total number M of installed fluid heaters, and when these fluid heaters receive the operation permission signal, the pilot combustion state is maintained during the combustion standby, By immediately shifting to the main combustion state when a combustion request is made, it is possible to secure a quick response to a load, prevent excessive fuel consumption, and achieve a great effect on energy saving.

[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.

[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 (1)

[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 While controlling according to the heating state, m units are selected in descending order of priority with respect to the total number M of installed fluid heaters 1, and when these fluid heaters 1 receive the operation permission signal, the combustion standby The inside is maintained in the pilot combustion state,
A control method in a multi-can installation system for a fluid heater, characterized in that a transition to a main combustion state is made immediately when a combustion request is made.