JP5394011B2 - Hot water supply system, distribution board - Google Patents

Description

  The present invention relates to a hot water supply system and a distribution board.

  In recent years, in addition to energy for household appliances such as refrigerators, washing machines, microwave ovens, etc., which have been driven by electricity, hot water supply in bathrooms and washstands, cooking in the kitchen, air conditioning in the living room, etc. All-electric homes that use electricity to supply all the energy needed in the living environment are widespread. Along with this, power is evenly distributed to each home appliance distributed in the house, and earth leakage circuit breakers, wiring breakers, etc. are integrally distributed for safe use of each home appliance. In order to increase the number of loads and applications that should be handled for all electrification, there is a need for further enhancement of functionality.

  For example, a distribution board disclosed in Patent Document 1 shown below includes a rectifier that converts commercial power from a commercial power source into DC power, a storage battery that stores DC power from the rectifier, and AC power (commercial power). An uninterruptible power supply with an inverter that converts DC power from the storage battery into AC power for the distribution panel load of necessary home appliances, etc. is installed, and the storage battery is stored during power outages and overloads The effect of realizing stable driving of the load on the distribution board is obtained by using the DC power that has been stored through the inverter.

  By the way, in hot water scenes performed in bathrooms, washstands, kitchens, etc., when hot water supply via a pipe from the hot water supply unit is stopped, the temperature of the hot water remaining in the pipe gradually decreases, Warm water that has remained in the pipe for a while and the temperature has dropped may flow out. For example, in winter, there is a realistic phenomenon in which only cold water comes out for a while even when the faucet of the mixer tap is twisted. Therefore, as in Patent Document 2 shown below, an immediate water heater is attached between the pipes from the hot water supply unit to the mixing plug and around the mixing plug, and when the hot water is supplied, the immediate water heater directly and instantaneously. A possible countermeasure is to boil hot water.

Furthermore, in this case, taking into account the realization of an all-electric house, the heater is not a gas instantaneous water heater that instantaneously boils hot water using the energy of city gas, which is generally popular, as the above-mentioned instant water heater. It is necessary to employ an electric heater type instant water heater that uses and heats cold water. That is, the instant water heater is handled as one load of a distribution board that distributes and supplies commercial power (AC power) from a commercial power source.
JP 2006-271097 A Japanese Patent Laid-Open No. 5-44993

  However, an electric heater type instant water heater (particularly a heater) consumes much larger electric power than a general home appliance. For this reason, even if the distribution board is provided with an overload countermeasure function, when the electric heater type instant water heater is handled in the same manner as other AC loads, the capacity of the inverter is increased (for example, 4 to 20 kVA). There is a need. Then, the introduction cost or the reconstruction cost of the hot water supply system increases, and there is a possibility that it will not spread to ordinary households.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a distribution board equipped with a storage battery and an inverter for an overload countermeasure function that constitutes a part of a hot water supply system, with an immediate hot water unit as a load. In this case, the direct current heater provided in the immediate hot water unit is directly driven from the storage battery to suppress the increase in capacity of the inverter.

The present invention includes a hot water supply unit that supplies hot water toward the mixing tap, an immediate hot water unit that heats hot water supplied from the hot water supply unit toward the mixing tap, the hot water supply unit, and the immediate hot water unit. A hot water supply system having a distribution board for distributing and supplying commercial power supplied from a commercial power source to a plurality of loads, wherein the instant hot water unit is driven by direct current power and heats hot water supplied with hot water The distribution board includes a rectifier that converts the commercial power into DC power, and is charged by the DC power converted by the rectifier, and discharges the charged DC power to drive the DC heater. A storage battery, an inverter that converts DC power charged in the storage battery into AC power, a current sensor that detects an amount of current supplied from the commercial power source, and the current Based on the determination result of whether or not the current amount detected by the sensor exceeds a predetermined reference current amount, the commercial power distributed and supplied to a part of the plurality of loads is switched to the AC power from the inverter. And a control circuit that controls charging / discharging of the storage battery, and the control circuit is configured to discharge the storage battery, to charge the storage battery, to charge the storage battery, from the discharge mode to the charging mode. a mode to wait for migration, when the amount of current detected by the current sensor in a state waiting for the transition a predetermined standby time from I Do less than a predetermined amount of reference current has passed, The charging / discharging of the storage battery is controlled by selecting one of the charging standby modes to be shifted to the charging mode.

  In addition, the system includes a voltage sensor that detects a voltage supplied from the commercial power supply, and the control circuit is based on a determination result of whether or not the voltage detected by the voltage sensor indicates a power failure. It is preferable to perform control to switch the commercial power distributed and supplied to all the plurality of loads to the AC power from the inverter.

Further, in the above system, the hot water supply unit is a part of the plurality of loads of the distribution board and is driven based on electric power supplied from the distribution board; and the heating It is preferable to have a hot water tank for storing hot water generated by driving the vessel.

  Moreover, it is said system, Comprising: It is preferable that the said storage battery is a lithium ion storage battery.

Furthermore, the present invention provides a plurality of loads including a hot water supply unit that supplies hot water toward the mixing tap, and an immediate hot water unit that heats hot water supplied from the hot water supply unit toward the mixing tap using a DC heater. On the other hand, a distribution board that distributes and distributes commercial power supplied from a commercial power source, the rectifier that converts the commercial power into DC power, and the DC that is charged and charged by the DC power converted by the rectifier A storage battery that discharges power to drive the DC heater of the immediate hot water unit, an inverter that converts DC power charged in the storage battery into AC power, and a current amount of the commercial power supplied from the commercial power supply A part of the plurality of loads based on a current sensor to be detected and a determination result of whether or not a current amount detected by the current sensor exceeds a predetermined reference current amount A control circuit that controls the switching of the commercial power supplied to the AC power from the inverter and controls charging / discharging of the storage battery, wherein the control circuit discharges the storage battery. A charging mode for charging the storage battery, a mode for waiting for the transition from the discharging mode to the charging mode, and a current amount detected by the current sensor in a state waiting for the transition is a predetermined reference current when a predetermined standby time from I Do and less than an amount of time, and wherein the charging standby mode to shift to the charging mode, by selecting any one mode among the controlling the charging and discharging of the storage battery To do.

  According to the present invention, the distribution board constituting a part of the hot water supply system directly drives the direct current heater of the instant hot water unit from the storage battery, thereby suppressing the increase in capacity of the inverter and realizing the hot water supply system at low cost. be able to.

=== Overall configuration of a hot water supply system using an instant hot water unit ===
FIG. 1 is a diagram illustrating an overall configuration of a hot water supply system using an immediate hot water unit according to the present embodiment.

  A hot water supply system 100 shown in FIG. 1 includes a water supply pipe 1 for supplying cold water from a predetermined water supply source to a hot water supply unit 10, a hot water supply unit 10, an immediate hot water unit 20, and an immediate hot water unit 20. The hot water supply pipe 2 for supplying hot water heated by the hot water supply unit 10 toward the water supply, the water supply pipe 3 for supplying cold water from a predetermined water supply source toward the mixing plug 32, and the immediate hot water unit 20 are mixed. A hot water supply pipe 4 for supplying hot water reheated by the hot water unit 20 toward the plug 32, a mixing plug 32 for mixing cold water supplied from the water supply pipe 3 and hot water supplied from the hot water supply pipe 4, The hot water supply object 30 and the distribution board 40 are mainly configured.

  The hot water supply unit 10 is part of a plurality of loads of the hot water storage tank 12 for storing the cold water supplied by the water supply pipe 1 and the distribution board 40, and is used for AC power (AC) supplied from the distribution board 40. And a heater 14 that heats the water driven and stored in the hot water storage tank 12. In addition, it is preferable that the hot water supply unit 10 is a nighttime electric water heater that operates by using cheap nighttime electric power in the midnight time zone. The hot water supply unit 10 may be a heater type that obtains heating energy by a heater or a heat pump type that obtains heating energy by heat exchange.

  The immediate hot water unit 20 includes a DC heater 22 and is a unit that heats hot water supplied from the hot water supply unit 10 toward the mixing plug 32 via the hot water supply pipe 2 by the DC heater 22.

  FIG. 2 is a view showing a configuration example of the immediate hot water unit 20. In the figure, the DC heater 22 is realized by a coil-shaped electric resistor 222 (for example, nichrome wire) connected between the plus electrode 221a and the minus electrode 221b. The electric resistor 222 is provided in the central path 211 in the housing 23, and hot water from the hot water supply pipe 2 is heated by the electric resistor 222 by passing through the central path 211 from the water inlet path 210, and hot water is supplied from the water outlet path 212. Supplied to the tube 4. Heat generation of the electrical resistor 22 is controlled by the controller 26 based on the detected temperature detected by the temperature sensor 24. For example, the controller 26 performs temperature control for causing the detected temperature to converge within a predetermined temperature range. In addition, a terminal block 27 is provided as an external interface for DC power applied to the plus electrode 221a and minus electrode 221b, AC power for driving the controller 26, control signals to the controller 26 and status signals from the controller 26.

  The hot water supply object 30 is intended for all living environments where hot water is supplied such as bath tubs, washstands, system kitchens, etc., for the realization of an all-electric house. From the cold water supplied from the water supply pipe 3 and the hot water supply pipe 4 A mixing plug 32 or the like for mixing hot hot water to be supplied with hot water and discharging or stopping hot water at an appropriate temperature is provided.

  The distribution board 40 has an overload countermeasure function and a power failure countermeasure function, and stably supplies AC power to a plurality of loads (50, 14, 20) including the hot water supply unit 10 and the immediate hot water unit 20. Is. Furthermore, the distribution board 40 supplies DC power directly to the DC heater 22 of the immediate hot water unit 20. In FIG. 1 (the same applies to FIGS. 6 to 9 described later), only three patterns of loads (50, 14, 20) are shown as the load of the distribution board 40 for convenience of explanation. The number may be large. Further, the load 50 represents a home electric appliance that is a general load of the distribution board 40. For example, the load 50 is an air conditioner or a television receiver arranged in a living room, a microwave oven arranged around a kitchen, or the like. is there.

  The distribution board 40 is disposed on an AC power line 401 that receives commercial power from the commercial power source 60, and has an earth leakage circuit breaker ELB that has both a function of interrupting current leakage and overcurrent, and converts commercial power into DC power. A rectifier 41 that is charged by the DC power converted by the rectifier 41, a battery 42 that discharges the charged DC power and drives the DC heater 22 of the instant hot water unit 20, and a DC power charged in the battery 42 The amount of current (that is, the amount of current consumed by a plurality of loads) provided from the commercial power source disposed on the AC power line 401 on the output side of the inverter 43 that converts to AC power and the leakage breaker ELB is detected. A current sensor 44, and a controller 45 that controls switching of switches SW1 to SW5 described later based on the amount of current detected by the current sensor 44. To.

  Various secondary batteries such as a lead storage battery, a nickel hydride storage battery, and a lithium ion storage battery can be adopted as the storage battery 42. However, since the direct current heater 22 with large power consumption is adopted as a part of the load of the storage battery 42 and a high current and high frequency charging / discharging is expected in view of the use form of the instant hot water unit 20, other In contrast to the secondary battery, it is preferable to employ a lithium ion storage battery that has almost no memory effect phenomenon (a phenomenon of memorizing a history of discharge at a shallow depth) and is suitable for additional charging and non-full charge storage.

Moreover, although the case where the output circuit of the inverter 43 is 100V is shown as a general example, since there are a single-phase 100V and a single-phase 200V as household power supplies, it is possible to output both 100V and 200V. is there. Since the single-phase 200V circuit is set to 200V by using a reverse-phase 100V circuit sharing the ground circuit, 100V and 200V are described in the same circuit here.
Furthermore, for example, a current transformer that detects the amount of current flowing through the power supply line 401 can be employed as the sensor 44.

  The distribution board 40 further includes a switch SW1 that is arranged on the AC power line 401 on the output side of the leakage breaker ELB and switches whether to cut off the supply of commercial power via the leakage breaker ELB, and an AC power supply A circuit breaker NFB1 that is arranged on one branch line 402a branched from the line 401 and cuts off the power supply to the load 50 in the event of an overcurrent, and one branch line 402b branched from the AC power line 401 Power supply to the immediate hot water unit 20 provided on the wiring breaker NFB2 which is disposed and cuts off the power supply to the electric water heater 14 at the time of overcurrent, and one branch line 402c branched from the AC power line 401 Switching between the circuit breaker NFB3 that shuts off the power supply in the event of an overcurrent and whether or not the commercial power distribution supply from the AC power supply line 401 to the branch line 402c is cut off. A switch SW2, a switch SW3 provided between the branch line 402c and the inverter 43, for switching whether to cut off the supply of AC power from the inverter 43 to the branch line 402c, a leakage breaker ELB, and a switch SW1 A switch SW4 that is disposed between the AC power line 401 and the rectifier 41 and switches whether to cut off the supply of commercial power from the AC power line 401 to the rectifier 41, and between the storage battery 42 and the DC heater 22. The DC circuit line 403 is disposed on the DC power line 403 and cuts off the supply of DC power from the storage battery 42 to the DC heater 22 in the event of an overcurrent, and the DC power line 403 between the storage battery 42 and the circuit breaker FB A switch SW that switches whether to cut off the supply of DC power from the storage battery 42 to the DC heater 22. And, with a. The switches SW1 to SW4 are AC switches, and the switch SW5 is a DC switch.

  With the above configuration, the controller 45 controls the opening and closing of the switches SW1 to SW5 when detecting the occurrence of an overload such that the amount of current detected by the sensor 44 exceeds a predetermined reference current amount, and a plurality of loads (50, 14, 20) provided with an overload countermeasure function (see, for example, the technique of Patent Document 1) for switching commercial power from the commercial power supply 60 distributed and supplied to a part of the AC power from the inverter 43.

  Moreover, the controller 45 detects the presence or absence of a power failure based on the voltage detected by the sensor 44 ′. When the occurrence of a power failure is detected, the controller 45 controls the opening and closing of the switches SW <b> 1 to SW <b> 5, thereby controlling a plurality of 100 V loads (50 20) A power failure countermeasure function for switching the commercial power from the commercial power source 60 distributed and supplied to all or a part to the AC power from the inverter 43 is provided. Note that the load supplied from the inverter 43 is selected within a range that can be supplied based on the amount of current detected by the sensor 44 before the power failure.

  Further, the controller 45 has a charge / discharge control function for controlling the charging / discharging of the storage battery 42 for hot water supply by controlling the opening / closing of the switches SW <b> 1 to SW <b> 5 based on the amount of current detected by the sensor 44. The charge / discharge control function includes a discharge mode in which the storage battery 42 is instantaneously discharged simultaneously with the start of hot water supply, a charge mode in which the storage battery 42 is charged, a mode in which the transition from the discharge mode to the charge mode is waited, and a predetermined waiting time And any one of the charging standby modes that shift to the charging mode when the current amount detected by the sensor 44 is less than the predetermined reference current amount (when no overload occurs). The charge / discharge control of the storage battery 42 is performed by selection.

  Note that the discharge mode is shifted to the case where the remaining capacity of the storage battery 42 is equal to or greater than a certain value (the depth of discharge is less than a certain value) in principle during the daytime. Moreover, charge mode starts charge immediately after switching from charge standby mode. In the charge standby mode, when switching from the discharge mode to the charge mode, whether or not charging is possible is determined, and if it is determined that charging is possible, the mode is shifted to the charging mode.

  Below, the detailed content of the switching conditions to the other mode at the time of each mode is demonstrated in order of discharge mode, charge standby mode, and charge mode.

=== Conditions for switching from discharge mode to charge standby mode ===
In the discharge mode, the setting is made so that the discharge is instantaneously started by the discharge start request. In any mode, the setting is made to switch to the discharge mode when the discharge is started.
Furthermore, the controller 45 performs control to switch the discharge mode to the charge standby mode in accordance with the conditions shown in the flowchart of FIG.

First, the controller 45 determines whether or not it is a charging time zone (for example, midnight time zone) of the storage battery 42 by a built-in timer (not shown) of the controller 45 (S301).
When it is determined that it is the charging time zone (S301: YES), the controller 45 has the discharge depth of the storage battery 42 (ratio of the amount of discharged electricity to the storage battery capacity) equal to or greater than the first reference depth (for example, 10%). Whether or not (S302).

  If the state of the storage battery 42 is less than the first reference depth (S302: NO), the controller 45 returns to S301 because charging is not required even during the charging time zone of the storage battery 42. On the other hand, if the state of the storage battery 42 is equal to or greater than the first reference depth (S302: YES) and the storage battery 42 is not discharging (S303: NO), the controller 45 sets the discharge mode to the charge standby mode. Switching (S304).

  If the state of the storage battery 42 is equal to or greater than the first reference depth (S302: YES), and the storage battery 42 is being discharged (S303: YES), the controller 45 determines that the state of the storage battery 42 is higher than the first reference depth. It is determined whether or not the second reference depth is high or higher (for example, 75%) (S305). If the discharge depth of the storage battery 42 is less than the second reference depth (S305: NO), the process returns to S303 because there is no need to charge the storage battery 42. On the other hand, when the state of the storage battery 42 is equal to or greater than the second reference depth (S305: YES), since the storage battery 42 needs to be charged, the controller 45 stops discharging the storage battery 42 by opening the switch SW5 or the like. Above (S306), the discharge mode is switched to the charge standby mode (S304).

  On the other hand, when it is not the charging time zone (S301: NO), it is a time zone during which the storage battery 42 is actively discharged, and the controller 45 determines whether or not the state of the storage battery 42 is equal to or greater than the second reference depth. Is discriminated (S307). If the state of the storage battery 42 is less than the second reference depth (S307: NO), the controller 45 returns to S301 because it is not necessary to charge the storage battery 42. On the other hand, when the state of the storage battery 42 is equal to or greater than the second reference depth (S307: YES), if the storage battery 42 is not discharging (S308: NO), the controller 45 promptly switches the discharge mode to the charge standby mode. (S304). If the state of the storage battery 42 is equal to or greater than the second reference depth (S307: YES) and the storage battery 42 is discharging (S308: YES), the controller 45 stops the discharge of the storage battery 42 by opening the switch SW5 or the like. After that, the discharging mode is switched to the charging standby mode (S304).

=== Conditions for switching from charge standby mode to other modes ===
In the charging standby mode, when discharging is started by the hot water supply start from the immediate hot water unit 20, the controller 45 immediately shifts from the charging standby mode to the discharging mode in consideration of user convenience. However, when the discharge depth of the storage battery 42 is large, a restriction is imposed not to discharge (so as not to shift to the discharge mode).

  Moreover, the controller 45 performs control which switches charging standby mode to charge mode according to the conditions shown by the flowchart of FIG.

  First, the controller 45 counts the time T elapsed from the start of the charging standby mode (T = 0) based on the unit time Δt (S400, S401), and based on the amount of current detected by the current sensor 44, the storage battery 42. It is determined whether or not an overload (detected current amount> predetermined reference current amount) is not caused by starting the charging to (S402). If overload occurs (S402: NO), the controller 45 returns to S401 and continues to count the time T. If it does not appear to be an overload (S402: YES), the controller 45 is in the charge standby mode and the standby time T1 has elapsed since it has not been overloaded even when charging is started (S402: YES). It is determined whether or not it is not performed (S403). If the standby time T1 has not elapsed (S403: YES), the controller 45 returns to S401 and continues counting time. If the standby time T1 has elapsed (S403: NO), the controller 45 switches the charge standby mode to the charge mode (S404).

  According to the above flow, even if the electric water heater 14 having a large charging current and operating with a large amount of power consumption is operated, for example, at midnight, it seems that the charging is in the charging standby mode and overload is caused by the start of charging. If there is (S402: NO), the charging standby mode is not switched to the charging mode. That is, the condition for starting charging is set so as not to overload after charging. As a result, the occurrence of overload due to the start of charging can be prevented in advance.

=== Conditions for switching from charge mode to other mode ===
In the charging mode, only charging is performed and discharging is not performed. Moreover, it can suppress that charging / discharging is started simultaneously by the setting which transfers to charge mode prior to charge start.
Moreover, the controller 45 performs control which switches charge mode to discharge mode or charge standby mode according to the conditions shown by the flowchart of FIG.

  First, the controller 45 determines whether or not the storage battery 42 is fully charged by being fully charged in the charging mode (S501). When the charging is completed (S501: YES), the charging of the storage battery 42 is terminated by opening the switch SW4 (S508), and the charging mode is changed to the discharging mode (S509).

  If charging has not been completed (S501: NO) and a discharge start request from the immediate hot water unit 20 due to the start of hot water supply has not been received (S502: NO), the charging time zone (for example, midnight time zone) ) Is determined by a built-in timer (not shown) of the controller 45 (S503). Then, as long as it is in the charging time zone (S503: YES) and the amount of current detected by the current sensor 44 does not exceed the reference current amount during charging of the storage battery 42 (S504: YES), the process proceeds to S501. Return and continue charging. On the other hand, if overload occurs (S503: YES, S504: YES), charging of the storage battery 42 is terminated by opening the switch SW4 (S505), and the charging mode is shifted to the charging standby mode (S506).

  In addition, when it is not a charge time slot | zone (S503: NO), if the state of the storage battery 42 is more than 2nd discharge depth (for example, 75%) (S507: YES), S501 (NO), S502 (NO) , S503 (NO) and S507 (YES) are repeated to continue charging. If the state of the storage battery 42 is less than the second depth of discharge (S507: NO), the charging of the storage battery 42 is terminated (S508), and the charge mode is shifted to the discharge mode (S509).

  Further, when charging is not completed (S501: NO) and a discharge start request is received from the immediate hot water unit 20 due to the start of hot water supply (S502: YES), the state of the storage battery 42 is not immediately shifted to the discharge mode. Is less than the second reference depth (S507: NO), the charging is continued by repeating the loop of S501 (NO), S502 (YES), and S507 (NO). If the state of the storage battery 42 is less than the second reference depth (S507: NO), the charging of the storage battery 42 is terminated (S508), and the charge mode is shifted to the discharge mode (S509).

  According to the above flow, in the charging mode, even when a discharge start request is generated during charging (S502: YES), if the state of the storage battery 42 is equal to or greater than the second reference depth (S507: YES), discharging is performed. The mode is not shifted, and charging is continued until the state of the storage battery 42 becomes less than the second reference depth (S507: NO), and then the mode is shifted to the discharge mode (S509). Further, in the case of shifting from the charging mode to the discharging mode, the charging is completed (S501: YES), the charging circuit is disconnected (S508), and the mode is shifted to the discharging mode (S509). By setting these conditions, it is possible to reliably prevent the storage battery 42 from being charged and discharged simultaneously.

  In addition, there is a possibility that the load capacity of the entire household will be overloaded by the charging current of the storage battery 42, but the earth leakage breaker ELB has a characteristic that cuts off the supply of commercial power when the overload state continues for a predetermined time. is there. For this reason, if it becomes an overload (S504: YES), a power failure can be prevented in advance by stopping charge during the predetermined time (S505).

  As described above, in the hot water supply system 100 described above, when the distribution board 40 having the overload countermeasure function sets the immediate hot water unit 20 as a new load, the direct current heater 22 provided in the immediate hot water unit 20 is directly connected to the storage battery 42. To drive. That is, since the ratio of the power consumption of the DC heater 22 to the power consumption of the instant hot water unit 20 is very large, the direct current is independent from the power supply source (commercial power supply 60) of the plurality of loads (50, 14). The power supply source of the heater 22 is a storage battery 42. As a result, it is not necessary to handle the immediate hot water unit 20 as an AC load of the distribution board 40 and it is not necessary to increase the capacity of the inverter 43, so that the hot water supply system 100 can be realized at low cost.

  Further, since the power consumption of the DC heater 22 is large, the charging / discharging current of the storage battery 42 increases, but protection against overload during charging / discharging of the storage battery 42 is appropriately performed based on the detection result of the current sensor 44. . Specifically, if an overload occurs during charging, charging is stopped, and if an overload occurs during discharging, a normal overload countermeasure is taken. As a result, the internal circuit of the distribution board 40 can be appropriately protected.

  Further, in the hot water supply system 100 described above, when the controller 45 detects the occurrence of a power failure based on the detection voltage of the voltage sensor 44 ′, all or some of the plurality of loads (50, 14) of the distribution board 40 are supplied with power. By switching the source to the AC power from the inverter 43, it is possible to appropriately take measures against power failure during charging and discharging.

  Further, in the hot water supply system 100 described above, the hot water supply unit 10 is configured by the electric water heater 14 that can use low-cost electric power in the midnight time zone, so that it is possible to suppress the electricity charge necessary for hot water supply. In addition, since the electric water heater 14 is used to make a contract for the midnight time zone, inexpensive power in the midnight time zone can be used when the storage battery 42 is charged and discharged.

  Further, in the hot water supply system 100 described above, in the charging standby mode, since it is determined that an overload is not caused by the start of charging as a condition for shifting to the charging mode (charging start condition), occurrence of an overload during charging Can be prevented in advance. In particular, when the storage battery 42 is charged in the midnight time zone in which the electric water heater 14 operates, the occurrence of an overload may be induced. Therefore, the setting of the charging standby mode is significant. In the hot water supply system 100 described above, if an overload occurs due to the operation of the electric water heater 14 while the storage battery 42 is being charged, the charging of the storage battery 42 is stopped and the charging standby mode is entered. Appropriate protection by the electrical panel 40 becomes possible.

  Moreover, in the hot water supply system 100 described above, the storage battery 42 is a lithium ion storage battery, so that it is possible to sufficiently cope with high-frequency charging and discharging with a large current.

  While the present embodiment has been described above, the above-described examples are for facilitating the understanding of the present invention, and are not intended to limit the present invention. The present invention can be changed / improved without departing from the gist thereof, and the present invention includes equivalents thereof.

It is the figure which showed an example of the whole structure of the hot-water supply system using the instant hot water unit of this embodiment. It is the figure which showed the example of 1 structure of the instant hot water unit of this embodiment. It is the figure which showed the control flow at the time of the discharge mode by the controller of this embodiment. It is the figure which showed the control flow at the time of the charge standby mode by the controller of this embodiment. It is the figure which showed the control flow at the time of the charge mode by the controller of this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Hot water supply unit 12 Hot water storage tank 14 Electric water heater 20 Instant hot water unit 22 DC heater 32 Mixing plug 40 Distribution board 41 Rectifier 42 Storage battery 43 Inverter 44 Current sensor 44 'Voltage sensor 45 Controller 50 Load 60 Commercial power supply SW1-SW5 switch

Claims (5)

A hot water supply unit that supplies hot water toward the mixing tap, an immediate hot water unit that heats hot water supplied from the hot water supply unit toward the mixing tap, and a plurality of loads including the hot water supply unit and the immediate hot water unit. A distribution board for distributing and supplying commercial power supplied from a commercial power source,
The instant hot water unit is
It has a direct current heater that heats hot water that is driven by direct current power and is supplied with hot water,
The distribution board is
A rectifier for converting the commercial power into DC power;
A storage battery that is charged with DC power converted by the rectifier, discharges the charged DC power, and drives the DC heater;
An inverter that converts DC power charged in the storage battery into AC power;
A current sensor for detecting an amount of current supplied from the commercial power supply;
Based on the determination result whether or not the current amount detected by the current sensor exceeds a predetermined reference current amount, the commercial power distributed and supplied to a part of the plurality of loads is converted to the AC power from the inverter. And a control circuit for controlling charging and discharging of the storage battery,
Have
The control circuit includes:
A discharge mode for discharging the storage battery;
A charging mode for charging the storage battery;
Said from the discharge mode a mode to wait for the transition to the charging mode, the transition of the amount of current detected by the current sensor in a state waiting is predetermined from I Do less than a predetermined amount of reference current If the waiting time has elapsed, the charging standby mode to shift to the charging mode,
A hot water supply system, wherein one of the modes is selected to control charging and discharging of the storage battery. The hot water supply system according to claim 1,
A voltage sensor for detecting a voltage supplied from the commercial power supply;
The control circuit switches the commercial power distributed and supplied to all of the plurality of loads to the AC power from the inverter based on a determination result of whether or not the voltage detected by the voltage sensor indicates a power failure. A hot water supply system characterized by performing control. The hot water supply system according to claim 1 or 2,
The hot water supply unit is
A heater that is part of the plurality of loads of the distribution board and is driven based on electric power supplied from the distribution board;
A hot water storage tank for storing hot water generated by driving the heater;
A hot water supply system characterized by comprising: The hot water supply system according to any one of claims 1 to 3,
The hot water supply system, wherein the storage battery is a lithium ion storage battery. From a commercial power supply to a plurality of loads, including a hot water supply unit that supplies hot water toward the mixing tap, and an immediate hot water unit that heats hot water supplied from the hot water supply unit toward the mixing tap using a DC heater. A distribution board for distributing and supplying commercial power to be supplied,
A rectifier for converting the commercial power into DC power;
A storage battery that is charged by the DC power converted by the rectifier, discharges the charged DC power, and drives the DC heater of the instant hot water unit;
An inverter that converts DC power charged in the storage battery into AC power;
A current sensor for detecting a current amount of the commercial power supplied from the commercial power source;
Based on the determination result whether or not the current amount detected by the current sensor exceeds a predetermined reference current amount, the commercial power distributed and supplied to a part of the plurality of loads is converted to the AC power from the inverter. And a control circuit for controlling charging and discharging of the storage battery,
Have
The control circuit includes:
A discharge mode for discharging the storage battery;
A charging mode for charging the storage battery;
Said from the discharge mode a mode to wait for the transition to the charging mode, the transition of the amount of current detected by the current sensor in a state waiting is predetermined from I Do less than a predetermined amount of reference current If the waiting time has elapsed, the charging standby mode to shift to the charging mode,
A distribution board that selects any one of the modes and controls charging and discharging of the storage battery.

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