JP2005184895A - Power supply system to single phase load having single phase private power generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform an exact system disconnection at a power system fault time and to continue a power supply to a specific single phase load which is faulted by the stop of the power supply in a power supply system for supplying a power to a single phase load by system interlocking a single phase output private power generator to a single phase 3-wire power system. <P>SOLUTION: A power supply system to the single phase load having the single phase private power generator includes a power supply circuit in which the single phase output private power generator is connected in parallel with the single phase load, one common line is connected to the neutral line of the single phase 3-wire power system and the other is connected to any one voltage line through a first electromagnetic contactor. When both the single phase 3-wire power system and the private power generator normally supply the power, the first electromagnetic contactor is a conducting state. When the power supply from the single phase 3-wire power system is stopped, the power generation by the private power generator is temporarily stopped, and simultaneously the first electromagnetic contactor is set to a non-conducting state, the power supply by the private power generator is restarted. When the power supply of the single phase 3-wire power system is restarted in this state, the power generation by the private power generator is temporarily stopped, the first electromagnetic contactor is set to the conductive state, and then the power generation of the private power generator is system interlocked and restarted. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention includes a single-phase two-wire AC 100V output private power generation system connected to a single-phase three-wire power system that feeds a single-phase three-wire AC 200V, and stops feeding the single-phase three-wire power system. The present invention relates to a power supply system that reliably supplies power to a specific single-phase AC 100V load indoors.

  As one of distributed in-house power generation devices, fuel cell power generation devices that generate power from fuel cells using city gas as raw fuel have been developed and put into practical use as highly efficient and environmentally friendly devices. In particular, development of a small-capacity model of about 1 kW output for general home use is actively promoted. The development of such small-capacity models aims to cover most of the power consumed by ordinary households by operating the grid with the power grid, reducing the purchase of electricity from the power company and reducing utility costs.

  In recent years, the power received by ordinary households has increased due to the increase in the capacity of air conditioners and the spread of induction heating type cooking heaters, and it has become necessary to supply power to home appliances that operate at a single-phase AC of 200V. On the other hand, there are many electrical appliances that operate with conventional single-phase AC 100V, and there is no prospect that the power source of all electrical appliances will be 200V. Therefore, power reception by a single-phase three-wire power system that can use both single-phase AC 200V and single-phase AC 100V is also common in general households.

  By the way, when a distributed private power generator such as a fuel cell power generator is operated in a grid connection with a commercial power system, the received power system and the power generation system of the power generator should in principle be the same. It is stipulated in “Guidelines for grid interconnection technology” by the Ministry. According to this, in order to perform system interconnection with the single-phase three-wire power system, in principle, the power generation method of the private power generator also requires a single-phase three-wire system and at least a single-phase AC 200V output.

  However, for example, the output voltage of a fuel cell employed in a 1 kW class small-capacity fuel cell power generator developed for general household use is often about several tens of volts DC. The conversion of the DC voltage to AC 200V is a factor that the power generation efficiency is lowered because the step-up ratio is too large. Therefore, it is convenient for the small-capacity fuel cell power generator to be connected to a single-phase three-wire power system that outputs a single-phase two-wire AC 100V and supplies a single-phase three-wire AC 200V.

  In addition, the “system interconnection technical requirement guideline” mentioned above requires that the power generator connected to the grid be disconnected from the commercial power system when an abnormality in the commercial power system such as a power failure is detected. ing. In many cases, this disconnection is performed by a control relay in the private power generator. Therefore, in a general household, when a power failure occurs and the private power generator is disconnected, the operation of all the load devices connected to the commercial power system is naturally stopped.

  On the other hand, in-house power generation devices themselves, particularly fuel cell power generation devices, are often capable of continuing power generation independently unless the supply of raw fuel gas is stopped. Therefore, even if a power failure occurs, another power supply line for independent operation is provided from the private power generator, and the user can change the connection individually. Further, when the commercial power system is restored, it is often often manually restored to the original connection state. However, such connection changes and manual operations are not only troublesome, but also have the disadvantage that they cannot be dealt with when the user is away from home. Therefore, when a power failure occurs in the commercial power system, it is convenient for ordinary households if the power supply system is automatically switched so that power is supplied to the load from the private power generator capable of continuous operation.

By the way, as mentioned above, the “system interconnection technical requirement guideline” requires that the received power system and the power generation system of the power generator are the same at present. However, in the case of grid connection with a single-phase three-wire power system, particularly when the power generation output is sufficiently small, there is an exceptional possibility that a single-phase two-wire AC 100V output is allowed. As a guideline for the small capacity, contents such as a guideline of 2 kW are being studied. Therefore, if regulations are relaxed in the future, it will not be long before the connection to a single-phase three-wire power system is permitted with a single-phase two-wire AC 100V output, with a small-capacity private power generator set at about 2kW. it is conceivable that.
JP 2003-70166 A

  The present invention has been made from this background, and the problem is that a single-phase two-wire AC 100V output private power generator is connected to a commercial power system that supplies a single-phase three-wire AC 200V to a single-phase load of a general household. A power supply system that can reliably supply power to a specific single-phase AC 100V load that can be reliably disconnected when a commercial power system malfunctions and causes a problem when power supply is stopped. There is to do.

  In order to achieve the above object, the invention according to claim 1 is directed to a single-phase two-wire AC 100V output private power generation connected to a single-phase three-wire power system (4) that feeds a single-phase three-wire AC 200V. A power supply system (1) for supplying power to a single-phase or a plurality of AC 100V single-phase loads (7) connected in parallel using the device (2), wherein the private power generator and the single-phase load are connected in parallel. The first common contact line is a neutral line (N phase) of the single-phase three-wire power system, and the other common line is a voltage line (R phase or T phase). The power supply circuit connected via (MC1) is configured, and the first electromagnetic contactor is in a conductive state in a state where both the private power generation apparatus and the single-phase three-wire power system are normally supplying power. When the power supply from the single-phase three-wire power system stops, the first electromagnetic contact When the power generation of the private power generation apparatus is temporarily stopped and power supply of the private power generation apparatus is resumed, and power supply of the single-phase three-wire power system is resumed in this state. The power generation by the private power generation apparatus is temporarily stopped to bring the first electromagnetic contactor into a conductive state, and then the power generation of the private power generation apparatus is restarted through grid connection.

  According to such a power feeding system, when the single-phase three-wire power system stops feeding, the private power generator is surely disconnected. The single-phase load can receive power even when the single-phase three-wire power system stops power feeding.

The invention according to claim 2 is the power feeding system according to claim 1, wherein the first electromagnetic contactor is in or near the power receiving board (5) of the power of the single-phase three-wire power system. It is characterized by being attached to.
With such a configuration, the existing wiring can be used for the secondary wiring of the first electromagnetic contactor.

According to a third aspect of the present invention, in the power feeding system according to the first or second aspect, the first electromagnetic contactor is made non-excited when the power generation of the private power generation device is completely stopped. It is characterized by being in a state.
With such a configuration, the power consumption in the first electromagnetic contactor can be reduced.

According to a fourth aspect of the present invention, there is provided the power feeding system according to any one of the first to third aspects, wherein the first or second single-phase load constituting the single-phase load is disposed near the power inlet. 1 is provided with dedicated outlets (8a, 8b) for receiving power from the secondary side of the electromagnetic contactor.
With such a configuration, it becomes easy to feed and stop feeding of an important single-phase load that is fed from the secondary side of the first electromagnetic contactor.

The invention according to claim 5 is the power feeding system according to claim 4, wherein the dedicated outlet is a display device (9a, 9b) that operates with electric power supplied to the dedicated outlet. It is characterized in that a display device is provided for informing either of the power supply stop state from the single-phase three-wire power system, the overload state of the private power generator, or both states.
With such a configuration, it is possible to easily know the power supply stop from the single-phase three-wire power system or the overload state of the private power generator.

  According to a sixth aspect of the present invention, in the power feeding system according to the fifth aspect, a priority level or priority order of power feeding is determined for each dedicated outlet, and the single-phase three-wire power system is in a power feeding stop state. In the case where the private power generation apparatus is overloaded, the priority level or the priority order is displayed on the display device.

  With such a configuration, it is possible to easily know the load that should be stopped when the private power generation device is overloaded, and by stopping the operation manually from the low priority load, The overload state of the power generation device is eliminated, and power supply with a higher priority load can be continued.

According to a seventh aspect of the present invention, in the power feeding system according to any one of the fourth to sixth aspects, a priority order of power feeding is determined for each of the dedicated outlets and the priority order is determined for the dedicated outlet. In the state where individual electromagnetic contactors (MC13a, MC13b) are provided in the middle of wiring and both the single-phase three-wire power system and the private power generator are normally supplying power, all the individual electromagnetic contactors are in a conductive state. When the power supply of the single-phase three-wire power system is stopped and the private power generator is overloaded, the first electromagnetic contactor is turned off and the private power generator is The individual electromagnetic contactor connected thereto is made non-conductive in order from the lower-priority dedicated outlet until the overload state is resolved.
With such a configuration, the power supply is automatically stopped in order from the load with the lowest priority, and the overload state of the private power generation apparatus is eliminated, so that the load with the higher priority can continue to receive the power supply.

The invention according to claim 8 is the power supply system according to any one of claims 1 to 7, wherein when the power supply of the single-phase three-wire power system is stopped, the single-phase load is A command signal is sent to a part or all of the device so as to reduce its power consumption.
If it does in this way, when the load which received the command signal reduces the power consumption, the overload state of a private power generation device will be canceled and electric power feeding will be continued.

The invention according to claim 9 is the power feeding system according to any one of claims 1 to 8, wherein a single-phase load (15) different from the single-phase load is provided, the single line being the single-phase three-wire. Connected to the neutral line of the electric power system, and the other line is connected to either the secondary side of the first electromagnetic contactor or the voltage line on the side where the first electromagnetic contactor is not connected. Of the single-phase three-wire in a state where both the single-phase three-wire power system and the private power generator are normally feeding power. When the power value fed to the first electromagnetic contactor from the power system is equal to or less than a predetermined value, the other line of the other single-phase load is the secondary of the first electromagnetic contactor. The second electromagnetic contactor is switched so as to be connected to the side of the single-phase three-wire power system. When the power value supplied to the contactor exceeds the predetermined value, the other line of the other single-phase load is connected to the voltage line on the side where the first electromagnetic contactor is not connected. As described above, the second electromagnetic contactor is switched.
With such a configuration, it is possible to improve the interphase imbalance of power supplied from the single-phase three-wire power system.

In the power supply system according to claim 9, when the power supply of the single-phase three-wire power system is stopped, the first electromagnetic contactor is non-conductive. In this state, power is supplied from the private power generator, and then the second electromagnetic wave is connected to the secondary side of the first electromagnetic contactor. When the contactor is switched, and the private power generator is overloaded in the switched state, the other line of the other single-phase load is a voltage at which the first electromagnetic contactor is not connected. The second magnetic contactor is switched again so as to be connected to the wire.
With such a configuration, another single-phase load can continue to be supplied even if the supply of the single-phase three-wire power system is stopped unless the private power generation apparatus is overloaded.

The invention according to claim 11 is the power supply system according to any one of claims 1 to 10, wherein the private power generation device, the display device, the single-phase load, and the power supply control circuit are wirelessly or wired. The network is connected, and information exchange between these devices and loads is performed through the network.
With such a configuration, more complicated and flexible information exchange becomes possible.

According to a twelfth aspect of the present invention, in the power feeding system according to any one of the first to eleventh aspects, a fuel cell power generator is used as the private power generator.
With such a configuration, the system can be interconnected with a single-phase AC 100V output. Therefore, in the case of a fuel cell with a low DC power generation voltage, the boost ratio can be reduced as compared with the case of a 200V output, so that the power generation efficiency is improved. can get.

  According to the power supply system of the present invention, when the single-phase three-wire power system stops power supply, the private power generator is reliably disconnected. In addition, an important single-phase load can continue to receive power even when the single-phase three-wire power system stops supplying power.

(First embodiment)
A power supply system according to a first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram illustrating an overall configuration of a power feeding system 1 according to the first embodiment. The power feeding system 1 is a power feeding system for homes and offices equipped with a private power generation device 2 having a small capacity of about 1 to 2 kW.

  The private power generator 2 includes a fuel cell 2a, an inverter 2b, and a control circuit 2c. The DC voltage generated by the fuel cell 2a is converted into a single-phase two-wire AC 100V by the inverter 2b and output. The control circuit 2c performs all controls such as ON / OFF of power generation of the private power generation device 2, generated power, output voltage, output frequency, and grid interconnection control. The control circuit 2c is also connected to the power supply control circuit 3, and controls the start / stop of power supply from the private power generator 2 based on the command. The control circuit 4c also informs the power supply control circuit 3 of operation states such as power supply start / stop of the private power generation device 2, generated power, and an overload state.

  The power feeding system 1 is connected to a commercial single-phase three-wire power system 4 that feeds a single-phase three-wire AC 200V. The single-phase three-wire power system 4 supplies two types of voltages, a single-phase AC 100V and a single-phase AC 200V, through three power supply lines including an R phase, an N phase, and a T phase. N-phase (neutral wire) is grounded, R-phase and T-phase are voltage wires, AC 100V is supplied between R-N phase, T-phase and N-phase, and AC 200V is supplied between R-phase and T-phase. The

  The three power supply lines of the single-phase three-wire power system 4 are drawn into the power supply system 1 through the wiring breaker 5a in the power receiving panel 5 provided near the indoor entrance where the power supply system 1 is installed. . The first electromagnetic contactor MC1 is connected to the secondary (load side) T-phase feed line of the circuit breaker 5a for wiring, and the output line of the private power generator 2 is supplied to the secondary side (load side). It is connected between an electric wire (hereinafter referred to as a T1-phase feed line) and an N-phase line. The single-phase two-wire AC 100V output that is the output of the private power generator 2 is supplied in a grid connection between the T1 phase and the N phase.

  In the power supply system 1, the load to be supplied is divided into two types: a general load 6 and a specific single-phase load (corresponding to the single-phase load described in claim 1, hereinafter referred to as a specific single-phase load) 7. Power is supplied. Here, the general load 6 refers to a load that does not cause a problem that causes a problem even if power supply is stopped for a long time due to a power failure or the like. For example, an electric washing machine and a dryer correspond to this. On the other hand, the specific single-phase load 7 indicates an important load that causes trouble even when power supply is stopped for a short time. For example, lighting, a fax machine, a television as an emergency information acquisition unit, and the like correspond to this.

  The general load 6 is directly connected to the secondary power supply line of the circuit breaker 5a. Here, the general load 6 means a group of a plurality of loads using AC 100V and AC 200V. On the other hand, the specific single-phase load 7 is in parallel with the private power generation device 2 and includes both an N-phase (neutral wire) line and a T1-phase feed line that is a secondary feed line of the first electromagnetic contactor MC1. Connect between. The specific single-phase load 7 is not necessarily a single load, and is usually a group of a plurality of loads connected in parallel using a single-phase AC 100V.

  The power supply control circuit 3 is a circuit that performs power supply control of the power supply system 1. The power feeding control circuit 3 is connected to the control circuit 2 c of the private power generation device 2 and can receive a signal regarding the operation state of the private power generation device 2. Conversely, the control circuit 2c can be instructed to stop and start the power supply by the private power generator 2. The power supply control circuit 3 includes R-phase and T-phase current signals supplied from the single-phase three-wire power system 4 to the power supply system 1, a voltage signal between the R phase and the N phase, and a voltage between the T phase and the N phase. A signal is also input.

  Next, the operation of the power feeding system 1 will be described. When the power supply from the single-phase three-wire power system 4 is normally performed and the private power generation device 2 is also in a state where the power generation can be normally performed, the power supply control circuit 3 makes the first electromagnetic contactor MC1 conductive. Then, the control circuit 2c of the private power generator 2 is instructed to start power generation and to supply the generated power through grid connection. Thereby, electric power is supplied from both the single-phase three-wire electric power system 4 and the private power generator 2 between the T1 phase and the N phase, and the specific single-phase load 7 can be supplied with the electric power.

  Next, when the power supply from the single-phase three-wire power system 4 is stopped, the power supply control circuit 3 immediately switches the first electromagnetic contactor MC1 to the non-conductive state. Stopping the power supply from the single-phase three-wire power system 4 is detected when the voltage signal between the R phase and the N phase input to the power supply control circuit 3 is reduced to a predetermined value or less. In addition to detecting the voltage value between the R-phase and the N-phase as described above, when a power failure signal and an abnormal signal are separately output from the power supply side of the single-phase three-wire power system 4, the power supply control is performed on the signal. An input to the circuit 3 may be made to determine whether power supply is stopped.

  The power supply control circuit 3 has a storage battery inside and is charged by the generated power of the private power generation device 2. Since the storage battery operates as a power source, it can operate even when the power generation of the private power generation device 2 is stopped. The first electromagnetic contactor MC1 is driven by the internal power supply of the power supply control circuit 3. The first electromagnetic contactor MC1 is brought into a conducting state in order to continue power supply from the single-phase three-wire power system 4 to the specific single-phase load 7 when the private power generator 2 is completely stopped due to a failure or the like. In order to reduce the power consumption of the power supply control circuit 3 at this time even slightly, the first electromagnetic contactor MC1 is opened and closed using a break contact (b contact) so as to be conductive in an unexcited state.

The power supply control circuit 3 detects the stop of power supply from the single-phase three-wire power system 4 and switches the first electromagnetic contactor MC1 to the non-conductive state. A command signal for temporarily stopping power feeding from the power generation device 2 is sent. Upon receiving the command, the control circuit 2c immediately stops the operation of the inverter 4b and stops power feeding.
The power supply control circuit 3 uses the auxiliary contact of the first electromagnetic contactor MC1 to confirm that the first electromagnetic contactor MC1 is surely turned off, and the private power generator 2 also supplies power. The stop is confirmed by receiving a status signal from the control circuit 2c. After confirming both, the power supply control circuit 3 sends a command signal instructing the control circuit 2c to resume power supply of the private power generator 2. The control circuit 2c receives the command signal and restarts the power supply from the inverter 2b.

  As a result, the specific single-phase load 7 is not able to receive power supply for a short time after the power supply of the single-phase three-wire power system 4 is stopped. Can continue. In addition, since the first electromagnetic contactor MC1 is immediately turned off at the same time when the power supply of the single-phase three-wire power system 4 is stopped, the disconnection of the private power generator 2 from the single-phase three-wire power system 4 is prevented. Surely done.

  After the power supply only by the private power generator 2 is resumed in this way, the power supply control circuit 3 checks the voltage value between the R phase and the N phase, and has the power supply from the single-phase three-wire power system 4 been resumed? Repeat the determination of NO. Then, when power supply restart is confirmed by the voltage value or a signal from the single-phase three-wire power system 4 side, a power supply stop command signal for the private power generator 2 is sent to the control circuit 2c. The control circuit 2 c receives the command signal, stops the power supply, and sends a power supply stop state signal to the power supply control circuit 3. The power supply control circuit 3 confirms this and brings the first electromagnetic contactor MC1 into a conducting state. And after confirming the conduction | electrical_connection state using an auxiliary contact, the command signal which restarts the electric power feeding of the private power generation device 2 is sent with respect to the control circuit 2c. In response to the command signal, the control circuit 2c is connected to the single-phase three-wire power system 4 to resume power supply from the private power generator 2. With the above control operation, the power feeding system 1 returns to a normal state in which power feeding is performed from both the single-phase three-wire power system 4 and the private power generator 2.

With such power supply control, the specific single-phase load 7 that is an important single-phase load cannot receive power supply for only a short time even if the single-phase three-wire power system 4 stops power supply. The driving operation can be continued.
Next, even if the power supply control as described above is performed, when the power supply of the single-phase three-wire power system 4 is stopped and the power is supplied only from the private power generator 2, the generated power of the private power generator 2 is specified. A shortage may occur with respect to the demand power required by the single-phase load 7. In order to cope with such a state, a countermeasure adopted by the power feeding system 1 of the present embodiment will be described.

The specific single-phase load 7 which is an important single-phase load is usually composed of a plurality of loads. In the present embodiment, a dedicated outlet for supplying power to each load constituting the specific single-phase load 7 is provided. FIG. 2 is a wiring diagram for explaining the connection relationship near the dedicated outlet.
FIG. 2 illustrates the case where the specific single-phase load 7 is configured by two single-phase loads 7a and 7b. Dedicated outlets 8a and 8b are attached to the single-phase loads 7a and 7b, respectively. A voltage between the T1 phase and the N phase is supplied to the dedicated outlets 8a and 8b. The dedicated outlets 8a and 8b are attached near the corresponding single-phase loads 7a and 7b. Therefore, when the power supply system 1 is constructed by remodeling work in a home or office where the existing indoor wiring is applied, the existing power supply lines are used as T1-phase and N-phase power supply lines up to the dedicated outlets 8a and 8b. Can be used. As described above, when the existing power supply line is used as the T1-phase power supply line, the first electromagnetic contactor MC1 may be attached in the power receiving panel 5 or in the vicinity thereof. By doing so, wiring construction costs can be reduced.

  In the power supply system 1 of the present embodiment, each of the dedicated outlets 8a and 8b is provided with display devices 9a and 9b that are configured in the vicinity thereof or integrally with the dedicated outlet. The display devices 9a and 9b are supplied with power from dedicated outlets 8a and 8b to which the display devices 9a and 9b are attached. On the display devices 9a and 9b, display lamps 10a and 10b for displaying that the power supply of the single-phase three-wire power system 4 is stopped, and a display for displaying that the private power generation device 2 is in an overload state Lamps 11a and 11b are attached. Lighting of these display lamps is controlled by a signal from the power supply control circuit 3. Therefore, the user can easily know the power supply stop state of the single-phase three-wire power system 4 and the overload state of the private power generator 2 from the lighting state of the display lamp.

  Further, on the display devices 9a and 9b, indicators 12a and 12b for displaying the priority level of power supply to the dedicated outlets 8a and 8b are attached. This priority level represents the priority of power supply when the private power generation device 2 is overloaded when the single-phase three-wire power system 4 is in a power supply stop state and power is supplied only from the private power generation device 2. The priority level is determined in advance and stored in the power supply control circuit 3. The display is displayed in response to a signal from the power supply control circuit 3 when the private power generation device 2 is overloaded in a case where the power supply is performed only from the private power generation device 2. Note that the overload state of the private power generation device 2 in this case refers to a state where the private power generation device 2 is still generating power within the overload tolerance range.

  When the user knows that the private power generation apparatus 2 is in an overloaded state by the display lamps 11a and 11b, the user confirms the priority level of power supply by the indicators 12a and 12b, and the dedicated outlets 8a and 8b having a low priority level. Stop operation in order from the load connected to. Thereby, the overload state of the private power generation device 2 is eliminated, and the situation where the overload state of the private power generation device 2 continues and the power generation of the private power generation device 2 stops can be avoided.

  As the priority level indicators 12a and 12b, for example, it is appropriate to use a numeric indicator, but display lamps 11a and 11b for displaying the overload state of the private power generator 2 without attaching the indicator, A dedicated outlet with a lower priority level may be replaced by a method of flashing at a faster cycle to notify the user. A priority order may be used instead of the priority level. Adopting the priority order enables finer control than using the priority level.

  In addition, when the private power generator 2 is overloaded, the power supply control circuit 3 sends a signal requesting a reduction in power consumption to the single-phase loads 7a and 7b connected to the dedicated outlets 8a and 8b. It is better to send more. When the single-phase loads 7a and 7b have such specifications that can accept such a request signal and reduce the power consumption, the power consumption of the specific single-phase load 7 as a whole is reduced and the private power generator 2 May be resolved.

  FIG. 3 shows another embodiment in which more aggressive measures are taken to eliminate the overload state when the private power generation device 2 is in an overload state. In FIG. 3, individual electromagnetic contactors MC13a and MC13b are attached in the middle of the power supply lines to the dedicated outlets 8a and 8b so that ON / OFF of power supply to the dedicated outlets 8a and 8b can be controlled. It is the same as that of FIG. 2 except having added individual electromagnetic contactors MC13a and MC13b.

  The conduction / non-conduction of the individual electromagnetic contactors MC13a and MC13b is controlled by the power supply control circuit 3. In the case where the single-phase three-wire power system 4 is in a power supply stop state and power is supplied only from the private power generation device 2, if the private power generation device 2 is in an overload state, the power supply control circuit 3 is determined in advance. In accordance with the priority level or priority order, the individual electromagnetic contactors connected to the dedicated outlets with lower priority are sequentially turned off to stop power feeding. In this way, the load power is forcibly reduced until the overload condition is eliminated, so the overload condition of the private power generator 2 is reliably eliminated within a short time.

(Second Embodiment)
FIG. 4 is a block diagram showing the overall configuration of the second embodiment of the present invention. A power feeding system 1a shown in FIG. 4 newly adds another single-phase load (corresponding to another single-phase load according to claim 9) 15 and a second electromagnetic contactor MC2 to the power feeding system 1 of FIG. It is a thing.
Another single-phase load 15 is not necessarily a single load, and is generally a group of a plurality of loads connected in parallel using AC 100V. One line of another single-phase load 15 is connected to the N-phase (neutral line) line, and the other line is connected to the R-phase or T1-phase feed line that is a voltage line by switching the second magnetic contactor MC2. It has come to be. The second electromagnetic contactor MC2 is an electromagnetic contactor having a break contact (b contact) and a make contact (a contact), and switching thereof is controlled by the power supply control circuit 3.

  The switching control of the added second electromagnetic contactor MC2 is performed as follows. In a state where power supply from the single-phase three-wire power system 4 is normally performed, when the power supplied to the power supply system 1 by the T-phase-N-phase power supply line is equal to or less than a predetermined value set in advance, Another single-phase load 15 is connected between the T phase and the N phase (neutral phase) which are voltage phases to which the first electromagnetic contactor MC1 is connected. Switch. On the other hand, when the power supplied to the power supply system 1 by the T-phase-N-phase power supply line exceeds the predetermined value, the R phase and N which are voltage phases to which the first electromagnetic contactor MC1 is not connected. The second magnetic contactor MC2 is switched so as to be connected between the phase (neutral phase).

  If such switching is performed, the interphase imbalance of the power supplied from the single-phase three-wire power system 4 can be reduced. Note that the power supplied to the power feeding system 1 by the T-phase / N-phase power feeding line is obtained by multiplying the instantaneous value because the T-phase current and the voltage signal between the T-phase and the N-phase are input to the power feeding control circuit 3. Or by using a wattmeter.

The above switching was for the case where the power supply from the single-phase three-wire power system 4 is normal. However, while the power supply is continuing, the switching from the single-phase three-wire power system 4 Next, a case where power feeding is stopped will be described.
When the feeding of the single-phase three-wire power system is stopped, the feeding control circuit 3 first switches the first electromagnetic contactor MC1 to the non-conducting state as in the case of the first embodiment. At the same time, the power supply from the private power generator 2 is temporarily stopped. The control circuit 2c confirms that the first electromagnetic contactor MC1 is in a non-conducting state by using the auxiliary contact of the first electromagnetic contactor MC1 and that the private power generator 2 has also stopped feeding. Receive and confirm the status signal from. After confirming both, the power supply of the private power generator 2 is resumed.

  Subsequently, the power supply control circuit 3 causes the second single-phase load 15 to receive power from the secondary T1 phase power supply line and the N phase (neutral line) of the first electromagnetic contactor MC1. The magnetic contactor MC2 is switched. If the private power generator 2 does not become overloaded in the switched state, power supply is continued as it is. However, the private power generator 2 is overloaded during power supply in the switched state due to the switching. In this state, the other single-phase load 15 is disconnected from the T1-phase power supply line on the secondary side of the first electromagnetic contactor MC1, and is connected to the voltage line to which the first electromagnetic contactor MC1 is not connected. The second electromagnetic contactor MC2 is switched so as to be connected between a certain R-phase feed line and N-phase (neutral line).

  If such switching is performed, even if the power supply of the single-phase three-wire power system is stopped, another single-phase load 15 is continuously supplied with power as long as the private power generator 2 is not overloaded. be able to.

(Modified Embodiment)
In the first and second embodiments, the first electromagnetic contactor MC1 is connected to the T phase that is one voltage line, but it may be connected to the R phase that is the other voltage line. In this case, the specific single-phase load 7 and the private power generator 2 are connected between the R phase and the N phase (neutral phase).

  In the embodiments described so far, the power supply control circuit 3 and the private power generation device 2, the display devices 9a and 9b, and the single-phase loads 7a and 7b have been connected by separate signal lines. Instead, information exchange may be performed by connecting these devices and loads with a wired or wireless network. In this way, more complicated and flexible information exchange becomes possible.

1 is a block diagram illustrating an overall configuration of a power feeding system according to a first embodiment. It is the electric power feeding circuit near the exclusive outlet of 1st Embodiment. It is another electric power feeding circuit vicinity of the exclusive outlet socket of 1st Embodiment. It is a block diagram which shows the whole structure of the electric power feeding system concerning 2nd Embodiment.

Explanation of symbols

In the drawings, 1 is a power supply system, 2 is a private power generation device, 3 is a power supply control circuit, 4 is a single-phase three-wire power system, 5 is a power receiving panel, 6 is a general load, 7 is a single-phase load (specific single-phase load) 8a and 8b are dedicated outlets, 9a and 9b are display devices, 15 is a single-phase load (another single-phase load), MC1 is a first electromagnetic contactor, MC2 is a second electromagnetic contactor, MC13a and MC13b Indicates an individual magnetic contactor.

Claims (12)

Single or multiple connected in parallel using a single-phase two-wire AC 100V output private power generator (2) connected to a single-phase three-wire power system (4) that feeds single-phase three-wire AC 200V A power feeding system (1) for feeding an AC 100V single-phase load (7),
The private power generation device and the single-phase load are connected in parallel, one common line thereof is a neutral line (N phase) of the single-phase three-wire power system, and the other common line is any one voltage line. A power supply circuit connected to the (R phase or T phase) via the first electromagnetic contactor;
In a state where both the private power generator and the single-phase three-wire power system are normally feeding, the first electromagnetic contactor (MC1) is in a conductive state,
When the power supply from the single-phase three-wire power system is stopped, the first electromagnetic contactor is brought into a non-conducting state and at the same time, the power generation of the private power generator is temporarily stopped, and then the private power generator Resume power supply,
In this state, when the feeding of the single-phase three-wire power system is resumed, the power generation by the private power generator is temporarily stopped and the first electromagnetic contactor is turned on, and then the private power generator A power supply system characterized by restarting power generation through grid connection.   2. The power feeding system according to claim 1, wherein the first electromagnetic contactor is attached in or near a power receiving panel (5) of the electric power of the single-phase three-wire power system.   3. The power feeding system according to claim 1, wherein in a state where power generation of the private power generation apparatus is completely stopped, the first electromagnetic contactor is in a conductive state without excitation.   Dedicated outlets (8a, 8b) that receive power from the secondary side of the first electromagnetic contactor are provided near the power inlets of some or all of the single-phase loads constituting the single-phase load. The power feeding system according to any one of claims 1 to 3.   A display device (9a, 9b) that operates on the power supplied to the dedicated outlet at the dedicated outlet, in a state where power supply from the single-phase three-wire power system is stopped or an overload state of the private power generator The power feeding system according to claim 4, further comprising a display device that notifies the state of either or both.   In the case where the private power generation apparatus is overloaded when the priority level or priority of power feeding is determined for each dedicated outlet, and the single-phase three-wire power system is in a power feeding stop state, 6. The power feeding system according to claim 5, wherein the priority level or the priority order is displayed on the display device. Prioritizing power supply for each of the dedicated outlets is provided, and individual electromagnetic contactors (MC13a, MC13b) are provided in the middle of wiring to the dedicated outlets for determining the priorities.
In the state where both the single-phase three-wire power system and the private power generator are normally feeding power, all the individual electromagnetic contactors are in a conductive state,
When feeding of the single-phase three-wire power system is stopped and the private power generator is overloaded, the first electromagnetic contactor is turned off, and the private power generator 7. The individual electromagnetic contactor connected thereto is made non-conductive in order from the dedicated outlet with the lower priority until the overload state is resolved. Power supply system.   When feeding of the single-phase three-wire power system is stopped, a command signal is sent to a part or all of the single-phase load so as to reduce the power consumption. The power feeding system according to any one of claims 1 to 7. A single-phase load different from the single-phase load is connected to the neutral line of the single-phase three-wire power system, and the other line is connected to the secondary side of the first electromagnetic contactor and the first line. A power supply circuit configured to be able to be switched and connected to any one of the voltage lines to which the first electromagnetic contactor is not connected by the second electromagnetic contactor (MC2);
In a state where both the single-phase three-wire power system and the private power generator are normally supplying power, the power value supplied from the single-phase three-wire power system to the first electromagnetic contactor is a predetermined value. Switching the second magnetic contactor so that the other line of the other single-phase load is connected to the secondary side of the first electromagnetic contactor if
When the power value supplied to the first electromagnetic contactor from the single-phase three-wire power system exceeds the predetermined value, the other line of the another single-phase load is the first 9. The power feeding system according to claim 1, wherein the second electromagnetic contactor is switched so as to be connected to a voltage line on a side where the electromagnetic contactor is not connected. When feeding of the single-phase three-wire power system is in a stopped state, the first electromagnetic contactor is in a non-conducting state and is fed from the private power generator.
Then, the second electromagnetic contactor is switched so that the other line of the other single-phase load is connected to the secondary side of the first electromagnetic contactor, and the private terminal is switched in the switched state. When the power generator is in an overload state, the second electromagnetic wave is connected to a voltage line to which the first electromagnetic contactor is not connected. The power feeding system according to claim 9, wherein the contactor is switched again.   The personal power generation device, the display device, the single-phase load, and the power supply control circuit are connected by a wireless or wired network, and information exchange between the devices and the load is performed through the network. The power feeding system according to any one of 10. The power supply system according to claim 1, wherein the private power generation device is a fuel cell power generation device.

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