JP2853346B2 - Electric water heater system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric water heater system to which a plurality of electric water heaters are connected.

[0002]

2. Description of the Related Art FIG. 3 is a block diagram showing a configuration of an electric water heater used in a conventional system of this type. In the figure, reference numeral 1 denotes an entire electric water heater, 2 denotes a power source, 3 denotes a transformer / rectifier, Is a microcomputer for controlling the entire water heater, 5 is a hot water temperature setting unit for setting the boiling temperature of the water heater, 6 is an automatic temperature controller, 7 is a hot water tank, and 8 is a heater mounted in the hot water tank 7. . The automatic temperature controller 6 includes an interface 6a for connection to the microcomputer 4, a hot water temperature detector 6b including a temperature detecting element for detecting the temperature of the hot water in the hot water tank 7, and a relay 6c for turning on / off the power supply to the heater 8. It is composed of

Next, the operation will be described. Electric water heater 1
Is turned on, power is supplied from power supply 2 and
This power is supplied to the microcomputer 4 after being rectified by the rectifier 3 at a predetermined voltage. Then, the microcomputer 4 operates and the automatic temperature control device 6 is transmitted from the microcomputer 4 via the interface 6a.
Is sent, the relay 6c is driven to energize the heater 8, and the water in the hot water storage tank 7 is heated.

The temperature of the hot water in the hot water storage tank 7 is constantly detected by the hot water temperature detecting section 6b. The water in the hot water storage tank 7 is heated by the heater 8, and the hot water temperature gradually rises. When the temperature reaches the set boiling temperature, this information is notified to the microcomputer 4, and the microcomputer 4 issues a command to drive the relay 6c to cut off the power supply to the heater 8. When the temperature of the hot water in the hot water storage tank 7 falls below the set temperature to a certain temperature or lower, this information is notified from the automatic temperature control device 6 to the microcomputer 4, and the microcomputer 4 operates to re-energize the heater 8, In this manner, the automatic adjustment of the hot water temperature in the hot water storage tank 7 is performed.
And in the conventional electric water heater system in which a plurality of electric water heaters as described above are connected, the above-described automatic adjustment of the hot water temperature is performed individually for each electric water heater,
Control taking into account the power load between the electric water heaters is not performed.

[0005]

The problem to be solved is that, in the conventional electric water heater system, control is not performed in consideration of the power load between the electric water heaters as described above. When the heaters of the water heater are energized all at once, the point is that the power load becomes too large. Therefore, it is necessary to construct a system capable of withstanding a high power load, and therefore, it is necessary to increase the contract ampere and make the wiring thicker, resulting in high cost and poor workability. Also, from the aspect of supplying power, there is a problem that load leveling is difficult to perform.

The present invention has been made in order to solve such a problem, and an object of the present invention is to provide an electric water heater system which suppresses the maximum instantaneous electric power consumption to a certain level or less and does not require special electric equipment.

[0007]

The electric water heater system according to the present invention is provided with a power load management device, and the power load management device receives specific information from each of the electric water heaters and needs to boil it up as soon as possible. The most important feature is that the electric water heater is selected and the water is heated for a predetermined time in order.

[0008]

In the electric water heater system according to the present invention, the electric water heaters for heating are individually given a priority order and the heaters are individually energized, so that all the electric water heaters are energized simultaneously. Can be avoided, and the instantaneous maximum power consumption can always be kept below a certain reference.

[0009]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a power load management device and one electric water heater used in one embodiment of the present invention. In the drawing, the same reference numerals as those in FIG. Thus, it is provided on the piping of the hot water storage tank 7 and detects the outflow amount (used amount) of the hot water. A communication device 10 is attached to each of the water heaters, and communicates various information described later between the water heater and a power load management device described later. Reference numeral 11 denotes a power load management device, and each communication device 1
"Current hot water temperature" from each water heater sent from 0,
Receives information on "set hot water temperature", "remaining hot water amount", and "hot water usage", calculates the required amount of heat, assigns temporal priorities, and monitors the load status of other water heaters in the system. , Which heater 8 is to be energized.

Next, the operation will be described. Electric water heater 1
The operation of the microcomputer 4 to boil water in the hot water storage tank 7 after the boiling command is sent from the power load management device 11 to the electric water heater 1 used in the conventional system
The operation is the same as that described above, and is omitted here. In addition, when starting up the system, if all the plurality of electric water heaters 1 start the boiling operation, the power load becomes large. Therefore, when starting up the system, the power load management device 11 The boiling operation is started with a priority (for example, energization is performed in the order of proximity).

FIG. 2 is a flowchart showing a control operation performed by the electric power load management device 11 in consideration of a load state between the electric water heaters 1, and S100 to S104 in FIG. First, in step S100, the power load management device 11 receives information (M) from each electric water heater 1 via the communication device 10. The contents of this information (M) include the current hot water temperature from hot water temperature detecting section 6b, the remaining hot water amount from remaining hot water detecting device 12, the amount of hot water used per unit time from flow rate sensor 9, and the hot water setting section. 5 and the tank capacity of the hot water tank 7, the electric capacity of the heater 8, and the thermal efficiency coefficient of the water heater, which are stored in the microcomputer 4 in advance.

In the next step S101, the time (T) required for boiling each electric water heater is calculated individually from the information (M) from each electric water heater 1 using the following equation. T = (tank capacity−remaining hot water quantity) × (set hot water temperature−current hot water temperature) / (heater capacity) × 860 × (thermal efficiency coefficient) (1) In the next step S102, each of the values obtained in step S101 is calculated. The boiling priority coefficient (P) is calculated from (T) and the amount of hot water used per unit time of the water heater. P = T × · (amount of hot water used per unit time) / (tank capacity) (2) In the next step S103, the power load management device 1
1 is the value of the largest value of the boiling priority coefficient (P) calculated in step S102 with respect to the water heater having the largest value.
Through the communication device 10 of the water heater, the microcomputer 4 issues an energization command to the heater 8 to boil the water, and issues a stop power command to the other water heaters.

In the next step S104, it is determined whether or not a predetermined time (A) has elapsed. (A) If the time (minutes) has elapsed, the flow returns to step S100, and new information (M) at this time is returned. The following control is performed by steps S101 to S101.
This is performed in step S104. That is, the water heater that has received the power supply command to the heater 8 operates the microcomputer 4 to operate the relay 6.
c is driven, the heater 8 is energized for (A) minutes, and the heater 8 is heated.

As described above, according to the present invention, the electric power load management device 11 receives the information from each electric water heater 1 and performs the heating for the predetermined time in the order of the electric water heaters that need the earliest heating. Therefore, it is possible to avoid a situation in which the energization of all the heaters 8 of each electric water heater 1 is started at once without affecting the operation state of the whole system, and the instantaneous maximum power consumption of the whole system is always kept below a certain standard. Can be held down.

In the above embodiment, a system using a diversion sensor as a device for detecting the amount of hot water used has been described, but a system using a flow switch may be used. Further, in the above-described embodiment, a system in which the microcomputer 4 controls the heater 8 of the water heater 1 by issuing commands to start / stop boiling to the microcomputer 4 of each electric water heater 1 by the power load management device 11. Although shown, a relay (not shown) may be provided in the power load management device 11 to directly open and close an electric path for supplying electric power to the heater 8 of the electric water heater 1, with the same effect as in the above embodiment.

Further, in the above-described embodiment, all the loads to be controlled are the electric water heaters 1. However, the present invention is not limited to the electric water heaters. Similar control can be performed, and the same effects as in the above embodiment can be obtained.

[0017]

As described above, the electric water heater system of the present invention is provided with a power load management device, and the power load management device needs to boil up the earliest while receiving feedback information from each electric water heater. By selecting electric water heaters and heating them in order, it is possible to avoid a situation in which all heaters of all electric water heaters are energized at the same time, always keep the power load of the entire system below a certain standard, and increase the contract ampere. This eliminates the need for installation work such as thickening and thickening the wiring, and makes it possible to construct a system with good workability and cost reduction. Further, from the aspect of supplying power, there is an advantage that the load can be leveled easily.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a power load management device and one electric water heater used in one embodiment of the present invention.

FIG. 2 is a flowchart showing a control operation performed by the power load management device of the present invention in consideration of a load state between electric water heaters.

FIG. 3 is a block diagram showing a configuration of an electric water heater used in a conventional system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electric water heater 2 Power supply 3 Transformer / rectifier 4 Microcomputer 5 Hot water setting part 6 Automatic temperature control device 7 Hot water tank 8 Heater 9 Flow rate sensor 10 Communication device 11 Power load management device

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-286653 (JP, A) JP-A 64-23057 (JP, A) JP-A-2-103338 (JP, A) JP-A 61-86 70337 (JP, A) JP-A-3-263546 (JP, A) JP-A-3-260553 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F24H 1/18 301 F24H 1/18 302

Claims (1)

(57) [Claims] In an electric water heater system to which a plurality of electric water heaters are connected, a “current hot water temperature”, a “set hot water temperature”, and a “remaining hot water temperature” are output from each of the electric water heaters.
Information on hot water volume and hot water usage per unit time
Communication device that communicates in real time, and the above information of each electric water heater from the communication device
Receive and determine the "tank volume" of each electric water heater
Amount, heater capacity, and thermal efficiency coefficient,
The time (T) required for boiling each electric water heater
In addition to the time required for boiling (T), use of hot water per unit time
Each electric water heater based on the dose and tank capacity information
The boiling priority coefficient (P) is determined, and the boiling priority of each electric water heater is determined based on the boiling priority coefficient (P). A power load management device that issues a command to perform boiling and repeats this operation; and each electric water heater that controls energization of its own heater by a command from the power load management device. Electric water heater system.