JP2018204832A - Electric instantaneous water heater demand control system - Google Patents

Abstract

To provide an electric instantaneous water heater demand control system capable of demand-controlling electric capacitance of a plurality of electric instantaneous water heaters without installing a controller.SOLUTION: In an electric instantaneous water heater demand control system, a plurality of instantaneous water heaters 10 with a microcomputer as a controller 20 is installed. The electric instantaneous water heater demand control system is configured to integrate cumulative output and output of an instantaneous water heater 10 next operating; when the total output exceeds a demand output maximum value, execute demand control means; reduce the output of the instantaneous water heater 10 next operating; and prevent the output from exceeding the demand output maximum value even in a case where the reduced output is added to the cumulative output.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an electric instantaneous water heater demand control system for demand-controlling the electric capacity of a plurality of electric instantaneous water heaters equipped with a “microcomputer” (hereinafter referred to as a microcomputer).

  Conventionally, Patent Document 1 describes a hot water supply system that performs demand control so as not to exceed the maximum demand power of contract power. This hot water supply system is configured to limit the amount of electric power used by a load other than the hot water storage type hot water heater when the remaining hot water amount of the hot water type hot water heater becomes smaller than a predetermined amount.

  On the other hand, as shown in Patent Document 2, the present inventors have invented an electric instantaneous water heater system that can control the electric capacity of the electric instantaneous water heater to save power consumption. In this system, the control device for controlling the system includes a power amount predicting means for predicting the power consumption amount for one unit when each instantaneous water heater is operated from the data of each sensor, and all the instantaneous water heaters in operation. When calculating the number of instantaneous water heaters that can be used at the same time from the preset upper limit power amount and exceeding the number that can be used simultaneously , A system configured to regulate power consumption of some selected instantaneous water heaters or all operating instantaneous water heaters.

JP 2012-32025 A Japanese Patent No. 6109776

  The system of Patent Document 1 that performs demand control on the power consumption of a hot water heater is a configuration in which the control device performs demand control by comprehensively evaluating the power consumption of a hot water storage water heater and the power consumption of a cooling / heating appliance or a lighting fixture. A complex and expensive system. Moreover, since the configuration is such that the state in which the amount of remaining hot water in the hot water storage tank of the hot water storage type hot water heater is less than a predetermined amount is detected and controlled, the electric instantaneous water heater that does not use the hot water storage tank cannot be controlled.

  On the other hand, in the system of Patent Document 2 proposed by the present inventor, a control device is separately installed in addition to a plurality of electric instantaneous water heaters, and this control device collects various data of each electric instantaneous water heater to obtain a plurality of data. It is the structure which controls an electric instantaneous water heater. For this reason, since the electric power is controlled specifically for the electric power used by the electric instantaneous water heater, the configuration can be made extremely simple compared to a system that comprehensively evaluates and controls the electric power used by an air conditioner or a lighting fixture. Moreover, since it is possible to collectively control the electric instantaneous water heaters installed in the entire building, the more efficient the control is possible as the number of electric instantaneous water heaters is increased.

  However, in the system of Patent Document 2, when the number of installed electric instantaneous water heaters is reduced, the installation cost of a separately installed control device is relatively increased. Thus, for example, controlling a small number of electric instantaneous water heaters installed on each floor of the building rather than the entire building using this system presents a cost-effective problem. Therefore, it has been desired to provide a system capable of efficiently demand-controlling the electric capacity of an electric instantaneous water heater installed on a relatively small scale.

  Therefore, the present invention was created to solve the above-described problems, and an electric instantaneous water heater capable of efficiently demand-controlling the electric capacity of a plurality of electric instantaneous water heaters without separately installing a control device. The purpose is to provide a demand control system.

In order to solve the above-mentioned problem, the first means of the present invention controls the output of the power used by a plurality of instantaneous water heaters 10 by using the microcomputer mounted on the instantaneous water heater 10 as the control device 20. A demand control system for an instantaneous water heater,
Each control device 20 connects the control devices 20 of all the instantaneous water heaters 10 to be controlled by signal lines, and outputs the output information during operation of each instantaneous water heater 10 to the adjacent instantaneous water heater 10 control device. 20, a memory function for storing a demand output maximum value set in advance for the power consumption of all the instantaneous water heaters 10, a demand output maximum value, and a cumulative output during operation. And a demand control means 100 for controlling the output of the instantaneous water heater 10 to be operated next by an arithmetic function for comparing and calculating
When the total output of the cumulative output and the output of the instantaneous water heater 10 that operates next exceeds the demand output maximum value, the demand control unit 100 corrects the output of the instantaneous water heater 10 downward. The corrected output is calculated, and the total output of the corrected output and the cumulative output is controlled so as not to exceed the demand output maximum value.

  In the second means, the instantaneous water heater 10 includes a temperature sensor 11 that senses the temperature of water supplied to the instantaneous water heater 10, and a flow rate sensor 12 that senses the amount of water supplied, and the control device 20 includes: The heat amount control means 200 for calculating the output that the instantaneous water heater 10 should originally output as the ideal output from the set temperature of the instantaneous water heater 10 and the data of each sensor is provided.

  The communication function of the control device 20 in the third means includes a loop signal line 30 through which a signal is transmitted in one direction, and the instantaneous hot water immediately before the transmission direction of the loop signal line 30 is reversed. The output information notified from the control device 20 of the water heater 10 is received, and the output information of the last instantaneous water heater 10 in the loop signal line 30 is notified to the first instantaneous water heater 10. Is.

  The communication function of the control device 20 of the fourth means is a communication line using radio.

  As in claim 1 of the present invention, when it is determined that the sum of the cumulative output notified by the communication function and the output of the instantaneous water heater 10 that is operated next exceeds the maximum demand output value by the calculation function. The demand control means 100 of the control device 20 of the instantaneous water heater 10 calculates a corrected output obtained by correcting the output of the instantaneous water heater 10 downward, and the total output of the corrected output and the cumulative output is the maximum demand output value. It is extremely efficient that the control device 20 provided in each instantaneous water heater 10 sequentially controls the total power consumption of the plurality of instantaneous water heaters 10 by controlling so as not to exceed Control became possible.

  As a result, it is not necessary to separately install a conventional control device or the like, and even when a small number of instantaneous water heaters 10 are installed, demand control that is cost-effective is possible.

  As described in claim 2, the instantaneous water heater 10 includes a temperature sensor 11 that senses the temperature of water supplied to the instantaneous water heater 10, and a flow rate sensor 12 that senses the amount of water supplied. Since it is provided with the calorific value control means 200 which calculates the output which the said instantaneous water heater 10 should output as an ideal output from the data of this and the setting temperature of the said instantaneous water heater 10, it mounts | wears with the instantaneous water heater 10 The control device 20 can always determine the ideal output that is optimal for the usage status of the instantaneous water heater 10.

  As in claim 3, the communication function of the control device 20 includes a loop signal line 30 through which a signal is transmitted in one direction, and a momentary expression immediately before the transmission direction of the loop signal line 30 is reversed. It is configured to receive output information notified from the control device 20 of the water heater 10, and is configured to notify the first instantaneous water heater 10 of the output information of the last instantaneous water heater 10 in the loop signal line 30. Therefore, even if the number of instantaneous water heaters 10 is arbitrarily changed, it is controlled in a system connected in a loop. Therefore, demand control can be easily performed only by changing the maximum demand output value.

  As described in claim 4, the communication function of the control device 20 can be used in a wider range of systems by using a communication line using radio.

  Thus, according to the present invention, the electric capacity of a plurality of electric instantaneous water heaters can be demand-controlled very efficiently without separately installing a control device as in the prior art.

It is the schematic which shows the usage example of this invention. It is the schematic which shows the loop-shaped signal line of the instantaneous water heater of this invention. It is a schematic diagram which shows one Example of the instantaneous type water heater of this invention. It is a block diagram which shows the structure of the control apparatus of this invention. It is a flowchart which shows one Example of this invention.

  The system of the present invention is a system configured to demand-control the total electric energy of a plurality of instantaneous water heaters 10 installed on, for example, one floor of a building (see FIG. 1). Each instantaneous water heater 10 is equipped with a microcomputer as a control device 20, and all the instantaneous water heaters 10 that perform demand control are connected by a loop signal line 30 (see FIG. 2).

  Each instantaneous water heater 10 includes a temperature sensor 11 that senses the water supply temperature and a flow rate sensor 12 that senses the amount of water supply (see FIG. 3). That is, the hot water heated by the heater 13 is directly supplied to the hot water tap 15. Further, a temperature control function mixing valve 14 having a temperature control function is connected to the pipe of the hot water tap 15, and a pipe for supplying water directly to the temperature control function mixing valve 14 is connected, so that the hot water temperature from the hot water tap 15 is connected. Can be further stabilized. In addition, the installation positions of the temperature sensor 11 and the flow sensor 12 can be arbitrarily changed.

  Data such as the water temperature and the flow rate obtained by the temperature sensor 11 and the flow rate sensor 12 are managed by the control device 20 provided in each instantaneous water heater 10.

  The control device 20 uses a microcomputer. The control device 20 includes a demand control unit 100 based on a communication function, a memory function, a calculation function, and a heat amount control function in advance (see FIG. 4).

  The communication function has a function of connecting all the instantaneous water heaters 10 with signal lines. And the output information during operation of each instantaneous water heater 10 is sequentially notified to the control device 20 of the adjacent instantaneous water heater 10.

  As the signal line, in addition to the one-way communication line and the loop signal line 30, a wireless communication line can be used. In the illustrated example, a loop signal line 30 is used. The loop signal line 30 is a signal line through which a signal is transmitted in one direction (see FIG. 2). That is, it is configured to receive output information notified from the control device 20 of the immediately preceding instantaneous water heater 10 opposite to the transmission direction of the loop signal line 30. Further, by notifying the first instantaneous water heater 10 of the output information of the last instantaneous water heater 10 in the loop signal line 30, the signal is always notified in a one-way loop shape.

  The memory function is a function for storing a demand output maximum value set in advance for the power consumption of all the instantaneous water heaters 10. The demand output maximum value is, for example, an electric energy that is arbitrarily set based on the total output of all the instantaneous water heaters 10 that are demand-controlled from the maximum demand power of the contract power. In the present invention, control is performed so that the cumulative operation output of the plurality of instantaneous water heaters 10 to be controlled does not exceed the arbitrarily set demand output maximum value.

  The calculation function is a function for comparing and calculating a demand output maximum value set in advance in the memory function and a cumulative output during operation notified by the communication function. Then, when it is calculated that the total output of the cumulative output and the output of the instantaneous hot water heater 10 to be operated next exceeds the maximum demand output value, the demand control means 100 is executed.

  The demand control means 100 calculates a corrected output obtained by correcting the output of the instantaneous water heater 10 downward, and controls so that the total output of the corrected output and the accumulated output does not exceed the demand output maximum value. That is, the demand control means 100 is a means for controlling the output of the instantaneous water heater 10 to be operated next based on the communication function, the memory function, and the calculation function of the control device 20. In addition, the control device 20 includes a heat control unit 200 together with the demand control unit 100 (see FIG. 4).

  The calorific value control means 200 is a means for calculating, as an ideal output, an output that the instantaneous water heater 10 should output from the set temperature of the instantaneous water heater 10 and data of each sensor. That is, based on the set temperature of the instantaneous water heater 10, information on the feed water temperature sensed by the temperature sensor 11 and the amount of water feed sensed by the flow sensor 12 is added, and the instantaneous water heater 10 originally outputs. The means for calculating the power output as the ideal output is the heat quantity control means 200.

  This ideal output is corrected downward to a corrected output when the demand control means 100 is executed. At this time, the demand control means 100 is configured to calculate a corrected output close to the ideal output of the instantaneous water heater 10 within a range not exceeding the demand output maximum value.

  FIG. 4 is a program configuration diagram showing the demand control means 100 and the heat quantity control means 200 provided in the control device 20. In the figure, ideal output (pwn) and corrected output (pwn`) are provided as shared information between the demand control means 100 and the heat quantity control means 200. Next, a description will be given based on (A) to (G) described in the program configuration diagram.

(A) In the heat quantity control means 200, when the water heater detects the specified flow rate by twisting the faucet, the heater operation is started.
Calculate the feedforward heat quantity (corresponding to the required heat quantity).
• When set temperature-feed water temperature> 0 [° C] Feed forward heat [kW] = flow rate [L / min] x (set temperature-feed water temperature) [° C] x 60 x 860
* 1 [kWh] = 860 [kcal], based on the calculation formula required for heating a general flowing liquid-Other than the above Feed forward heat [kW] = 0 [kW]

(B) Calculate the ideal output (pwn) [%] with the 5kW heater as the basic 100% from the feedforward heat quantity.
<Example> If the feedforward heat quantity is 3kW, it will be%.

(C) The demand control means 100 calculates a corrected output pwn ′ [%] from the ideal output (pwn).
Calculate maximum output ... ideal output ...
・ If this value is 1 or more (or ...? ・ = 0), set pwn to demand correction output ... '.
・ If this value is ........ ?? <1, set ...'......? ...?.

(D) Calculate the ideal output total (pwn) [%].
Δp which is the amount of change in the ideal output is calculated, and the value obtained by adding this value Δp to the received... Is sent to the device n + 1 as PWn.

(E) A corrected heat quantity [kW] (effective heat quantity) is calculated from the feedforward heat quantity and the corrected output pwn ′. Corrected heat quantity [kW] = Feedforward heat quantity [kW] x Corrected output pwn ’[%]

(F) Calculate a feedback correction value [%] based on 100%.
・ When (Set temperature-Hot water supply temperature)> “Determination temperature difference of feedback correction” Add 1% of the feedback correction value [%].
・ When (Hot water temperature-Set temperature)> “Determination temperature difference of feedback correction” Subtract 1% of the feedback correction value [%].
The feedback correction value is adopted only when the feedback correction value is smaller than the corrected output pwn '.
Corrected heat quantity [kW] = Feedforward heat quantity [kW] x Feedback correction value [%]
* If the feedback correction value is larger, it is not used because the power used by demand control and the water supply temperature are not stable (hunting occurs).

(G) Heater control method The amount of time the heater should be turned on per second is calculated from the corrected heat quantity.
The on-time is determined from the type of heater to be installed (eg, power consumption 5kW) at the specified sampling period.

  FIG. 5 is a flowchart showing the movement of the device n when calculating the ideal output (pwn) and the corrected output (pwn ′) of the instantaneous water heater 10. As shown in this figure, when the ideal output (pwn) of the next instantaneous water heater 10 is added to the cumulative output (PWn), the cumulative output (PWn) exceeds the maximum demand output value (Dmax). When judged, the demand control means 100 calculates a corrected output (pwn ') obtained by correcting the output of the instantaneous water heater 10 downward, and the demand output maximum value (Dmax) even if the next instantaneous water heater 10 is operated. ) Is controlled within a range not exceeding.

(Legend of Table 1)
-Dmax (%): “Demand output maximum value” is a value that is input in advance to all devices (the same value), and is arbitrarily set in advance from the total output upper limit value of all connected devices (all devices are This output is not exceeded even when turned ON).
• Status: Indicates whether the device is ON or OFF.
• pwn (%): “Ideal output” that the device should output, and n indicates the device number. Ex: pw1 is the ideal output of device 1.
・ △ pn (%): The amount of change from the ideal output of the previous round of each device.
-PW (%): “Ideal output total” Total value of ideal outputs of all connected devices.
Dmax / PW: “Demand judgment value”. When this value is less than 1, pw ′ = pw × Dmax / PW. When PW = 0, the calculation is the same as 1 or more.
• pwn '(%): “Corrected output” Output limited by demand (actual output), calculated with pwn ′ = pw × Dmax / PW.
-PW '(%): "Total corrected output" Total value of all connected devices

  Table 1 is a table explaining the demand control program of the present invention. In this explanation example, six units (device numbers 1 to 6) are connected to the loop signal line 30 in one direction, and each device outputs 100% when turned on. Further, in the table, “circumference” indicates the number of times the data of the first device 1 has been sequentially transferred to the last device 6 (return from the device 6 to the device 1). In this program, there is a case where the demand upper limit (Dmax) is temporarily exceeded, but since one round is very short (within 1 second), there is no problem of dropping the circuit breaker. By the way, with a breaker of 30A or less, it is within 2 minutes at 200% of the rated current and within 60 minutes at 125% (in JIS C8201-2-1 / 2-2Ann2, the tripping time of the breaker operation is Is defined).

  In Circulation 1, since only the device 1 is operating, the demand determination value (Dmax / PW) becomes smaller than 1 and does not need to be corrected downward.

In round 2, device 1 receives PW (100) from device 6. Since there is no change in output (Δp1 = 0), the PW remains at 100 and is passed to the device 2.
Device 2 receives PW (100) from device 1. Since it is ON, Δp2 = 100 and PW = 100 + 100 = 200 is passed to the device 3. Further, since Dmax / PW = 0.75 <1, the corrected output which is an actual output is pw2 ′ = pw2 (100) × Dmax / PW (0.75) = 75. At this time, the actual corrected output total PW ′ = 175, which exceeds Dmax.
The device 3 receives the PW (200) from the device 2. Since it remains OFF, pass PW (200) to 4 as it is. PW 'remains at 175.
The device 4 is the same as the device 3.
The device 5 receives the PW (200) from the device 4. Since it is turned ON, Δp5 = 100 and PW = 200 + 100 = 300 is passed to the device 6. Since Dmax / PW = 0.5 <1, the corrected output pw5 ′ = pw5 (100) × Dmax / PW (0.5) = 50. At this time, the actual corrected output total PW ′ = 225, which exceeds Dmax.
The device 6 is the same as the device 3 and the device 4.

In lap 3, device 1 receives PW (300) from device 6. Since there is no change in output, PW remains at 300 and is passed to device 2. However, since Dmax / PW = 0.5 <1, the corrected output pw1 ′ = pw1 (100) × Dmax / PW (0.5) = 50. At this time, PW ′ falls to 175.
The device 2 receives the PW (300) from the device 1. Since there is no change in output, PW remains at 300 and is passed to device 3. However, since Dmax / PW = 0.5 <1, the corrected output pw2 ′ = pw2 (100) × Dmax / P
(0.5) = 50. At this time, PW ′ decreases to 150 and converges within Dmax. Converge within one lap.
The device 3 receives the PW (300) from the device 2. Since it remains OFF, the PW (300) is passed to the device 4 as it is. PW 'remains at 150.
The device 4 is the same as the device 3.
The device 5 receives the PW (300) from the device 4. Since there is no change in output, the PW remains at 300 and is passed to the device 6.
The device 6 is the same as the devices 3 and 4.

DESCRIPTION OF SYMBOLS 10 Instantaneous water heater 11 Temperature sensor 12 Flow sensor 13 Heater 14 Mixing valve 15 with a temperature control function Hot water tap 20 Controller 30 Loop signal line 100 Demand control means 200 Calorie control means

Claims (4)

A demand control system for an instantaneous water heater that controls the output of power used by multiple instantaneous water heaters by using a microcomputer mounted on the instantaneous water heater as a control device,
Each control device connects all the instantaneous water heater control devices to be controlled via a communication line, and sequentially notifies output information during operation of each instantaneous water heater to the adjacent instantaneous water heater control device. A memory function for storing a demand output maximum value set in advance for the power consumption of all instantaneous water heaters, and a calculation function for comparing and calculating the demand output maximum value and the accumulated output during operation; By providing demand control means for controlling the output of the instantaneous water heater to be operated next,
The demand control means, when it is calculated that the total output of the cumulative output and the output of the next instantaneous water heater to be operated exceeds the maximum demand output, the corrected output obtained by downwardly correcting the output of the instantaneous water heater The electric instantaneous water heater demand control system is characterized in that it is a means for controlling the total output of the corrected output and the cumulative output so as not to exceed the maximum demand output value.   The instantaneous water heater includes a temperature sensor that senses the temperature of water supplied to the instantaneous water heater, and a flow rate sensor that senses the amount of water supplied, and the control device includes a set temperature of the instantaneous water heater and each temperature The electric instantaneous water heater demand control system according to claim 1, further comprising a calorific value control means for calculating an output that should be output from the instantaneous water heater as an ideal output from sensor data.   The communication function of the control device includes a loop signal line through which a signal is transmitted in one direction, and is notified from the control device of the immediately preceding instantaneous water heater opposite to the transmission direction of the loop signal line. 2. The electric instantaneous water heater demand control system according to claim 1, wherein the electric instantaneous water heater demand control system is configured to receive the output information, and configured to notify the first instantaneous water heater of the output information of the last instantaneous water heater in the loop signal line.   The electric instantaneous water heater demand control system according to claim 1, wherein the communication function of the control device is a communication line using radio.

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