JP7253725B2 - power generation system - Google Patents

Description

The present disclosure relates to power generation systems that control power .

In a photovoltaic power generation system, surplus power is reverse-flowed to a commercial power line and sold to a power company. On the other hand, in order to suppress voltage fluctuations in the power system due to reverse power flow, reverse power flow from the photovoltaic power generation system to the power company is avoided. For example, a power conditioner that controls the power generated by a solar cell is connected to a power generation control device that controls the output of the power conditioner. Based on this, an output command value is calculated and output to the power conditioner (see Patent Document 1, for example).

Japanese Patent No. 6364567

Cubicle-type high-voltage power receiving equipment (hereinafter referred to as "cubicle") is often installed in small and medium-sized facilities such as factories, large-scale commercial facilities, hospitals, office buildings, hotels, and stores with a power receiving capacity of 50 kVA or more and 4000 kVA or less. be. A cubicle is a substation facility in which a set of equipment for receiving high-voltage power is housed in a metal outer box. The facility is also equipped with a watt-hour meter that measures the power used in the facility at the facility, and the watt-hour meter is used by retail electricity utilities for power trading. Furthermore, the purpose of photovoltaic power generation systems is shifting from selling power to self-consumption. In the case of self-consumption, a measurement control device is required to measure the power of purchased power and adjust the generated power so that reverse power flow does not occur. When these facilities are connected to the photovoltaic power generation system described above, the scale of the facilities increases.

The present disclosure has been made in view of such circumstances, and an object thereof is to provide a technique for suppressing expansion of the scale of facilities in a power generation system.

In order to solve the above problems, a power generation system according to one aspect of the present disclosure includes functions for transforming high-voltage AC power from a power system, outputting the transformed AC power, and measuring the power of the purchased power. a power conditioner that converts the DC power generated in the power generator into AC power and outputs it, and the cubicle and the power conditioner are connected to output the AC power from the cubicle or the power conditioner to the load equipment and a power meter that measures the power that is bought and sold to the power system and transmits the measurement result to the power conditioner. The power conditioner consists of an input unit that receives the measurement results from the watt-hour meter, and a control unit that controls the conversion from DC power to AC power based on the measurement results received by the input unit so that power is not sold. , provided.

Another aspect of the disclosure is also a power generation system. This power generation system transforms high-voltage AC power from the power grid, outputs the transformed AC power , and includes a cubicle that does not include a function for measuring the power of the purchased power, and a direct current generated by the power generation device. A power conditioner that converts electric power into AC power and outputs it, a distribution board that is connected to the cubicle and the power conditioner and supplies the AC power from the cubicle or the power conditioner to load devices, and a power system and a current sensor that measures a current that is bought and sold and transmits the measurement result to the power conditioner. The power conditioner includes an input unit that receives the measurement result from the current sensor, a control unit that controls conversion from DC power to AC power so as not to sell power based on the measurement result received at the input unit, Prepare.

Yet another aspect of the present disclosure is also a power generation system. This power generation system transforms high-voltage AC power from the power grid, outputs the transformed AC power , and includes a cubicle that does not include a function for measuring the power of the purchased power, and a direct current generated by the power generation device. A main power conditioner that converts electric power into AC power and outputs it, a slave power conditioner that converts the DC power generated by the generator into AC power and outputs it, and a cubicle, main power conditioner, and slave power conditioner. A distribution board that supplies AC power from cubicles, main power conditioners, or slave power conditioners to load equipment, and the power that is bought and sold to the power system is measured, and the measurement results are used as the main power and a power meter that transmits to the conditioner. The main power conditioner has an input unit that receives measurement results from the watt-hour meter, and a control unit that controls the conversion from DC power to AC power based on the measurement results received at the input unit so that power is not sold. and The main inverter directs the operation of the conversion to the slave inverters.

It should be noted that any combination of the above-described components and expressions of the present disclosure converted between methods, devices, systems, computer programs, recording media recording computer programs, etc. are also effective as aspects of the present disclosure. be.

According to the present disclosure, it is possible to suppress the expansion of the scale of equipment in the power generation system.

1 is a diagram showing the configuration of a power generation system to be compared with Example 1. FIG. 1 is a diagram showing a configuration of a power generation system according to Example 1; FIG. 3(a) and 3(b) are diagrams showing data structures of tables held in the control unit of FIG. 2. FIG. FIGS. 4(a) and 4(b) are flow charts showing processing procedures by the power generation system of FIG. FIG. 7 is a diagram showing the configuration of a power generation system according to Example 2; FIGS. 6A and 6B are diagrams showing data structures of tables held in the control unit of FIG. 7(a) and 7(b) are flow charts showing processing procedures by the power generation system of FIG.

(Example 1)
Before specifically describing the embodiments of the present disclosure, an outline of the present embodiments will be described. Example 1 relates to a power generation system such as a solar cell system. High-voltage power is supplied from the power system to small and medium-sized facilities, and the high-voltage power is transformed by cubicles. The transformed electric power is supplied to load equipment through distribution boards in small and medium-sized facilities. On the other hand, when a power generation system is introduced into a small and medium-sized facility, a power generation device such as a solar cell is connected to a power conditioner, and the power conditioner is connected to a distribution board. The power conditioner, for example, converts the DC power generated by the power generator into AC power and outputs the AC power to the distribution board. In such a power generation system, the power generated by the power generation device is sold by reverse power flow to the power system via the power conditioner, the distribution board, and the cubicle.

However, as the purchase price of electricity continues to decline, the purpose of power generation systems is shifting from selling electricity to self-consumption. When realizing self-consumption of the power generation system, a reverse power flow relay (RPR) is provided in the cubicle to prevent the occurrence of reverse power flow into the power system. Since it is necessary to stop the power conditioner when the RPR operates, a measurement control device is provided in the cubicle to prevent this. The measurement control device measures the power of the purchased power, generates a command for adjusting the generated power so that reverse power flow does not occur, and outputs the command to the power conditioner.

The cubicle is also equipped with a watt-hour meter for measuring the power used in the small and medium-sized facilities. Electricity meters are used for confirmation by electric power retailers, and measurement control devices are used for controlling power conditioners, and their uses are different. However, since each of them has a function of measuring electric power, it can be said that a plurality of devices having the same function are included in the power generation system. In order to suppress the expansion of the scale of equipment in the power generation system, it is desirable that the power generation system does not include a plurality of devices having the same function.

In the power generation system of the present embodiment, no measurement control device is provided in the cubicle, and a function for controlling the operation of the power conditioner so as not to generate reverse power flow is provided in the power conditioner among the measurement control devices. be done. In addition, the power conditioner is equipped with a function to receive the measurement result of the power meter from the power meter. Operate.

FIG. 1 shows the configuration of a power generation system 1 to be compared. The power generation system 1 includes a power system 10 , a cubicle 20 , a power meter 30 , a distribution board 40 , a load device 50 , a power generator 60 and a power conditioner 70 . The cubicle 20 includes a measurement control section 22 and an RPR 24 , and the power conditioner 70 includes an input section 74 and a conversion section 72 . As described above, the power generation system 1 is installed in a small-medium scale facility with a power receiving capacity of 50 kVA or more and 4000 kVA or less. Examples of small and medium-sized facilities are factories, large commercial facilities, hospitals, office buildings, hotels, shops, and the like.

The power system 10 is provided by a power company or the like. Here, it is assumed that high voltage power of 6600V is provided. As described above, the cubicle 20 has a transformer function and performs transformation between high voltage power at 6600V and power at 100V or 200V. The distribution board 40 is connected to the cubicle 20 and connected to the power system 10 via the cubicle 20 . Moreover, the distribution board 40 connects the load device 50 and supplies power to the load device 50 . The load device 50 is a device that consumes power supplied from the distribution board 40 . The load device 50 includes devices such as an air conditioner (air conditioner), a television receiver (television), a lighting device, and a refrigerator. Although one load device 50 is connected to the distribution board 40 here, a plurality of load devices 50 may be connected to the distribution board 40 .

The power meter 30 is a digital power meter connected to the cubicle 20, such as a smart meter. The watt-hour meter 30 can measure forward flow power coming from the power system 10 or reverse power flow going out to the power system 10 . The former corresponds to purchased power or forward flow power, and the latter corresponds to sold power or reverse flow power. Electricity meters 30 are installed in small and medium-sized facilities for verification by retail electricity suppliers.

The power generation device 60 is, for example, a solar cell, and is a renewable energy power generation device. The power generator 60 utilizes the photovoltaic effect to convert light energy directly into electrical power. As solar cells, silicon solar cells, solar cells using compound semiconductors as materials, dye-sensitized solar cells (organic solar cells), and the like are used. Since the intensity of sunlight, which is renewable energy, fluctuates with the weather and the time of day, the power generated by the power generator 60 also fluctuates. The power generator 60 outputs the generated DC power to the power conditioner 70 .

The conversion unit 72 of the power conditioner 70 has the functions of a DC-DC converter and a DC-AC inverter, converts the DC power output from the power generation device 60 into DC power of a desired voltage value, and converts the converted DC Converts electrical power to AC power. The converter 72 outputs the converted AC power to the distribution board 40 . When selling the power generated by the power generation device 60 , the distribution board 40 outputs the AC power from the conversion unit 72 to the power system 10 via the cubicle 20 . However, since this embodiment assumes self-consumption rather than selling power, the distribution board 40 supplies the AC power from the conversion unit 72 to the load device 50 .

Assuming self-consumption, the cubicle 20 is provided with an RPR 24 in order to prevent reverse power flow. The RPR 24 is a relay that operates when AC power in a direction from the distribution board 40 to the power system 10, that is, in a reverse power flow is detected. For example, when a reverse current flows, the RPR 24 transmits a contact signal to the power conditioner 70, and the power conditioner 70 stops power generation. In this way, the RPR 24 operates when a reverse power flow to the power system 10 occurs, thereby stopping power transmission from the power generator 60 and the power conditioner 70 when a reverse power flow occurs, Prevent reverse power flow.

The measurement control unit 22 can measure forward power flow power coming from the power system 10 or reverse power flow power going out to the power system 10, and performs conversion in the conversion unit 72 based on the measurement results. A command for control (hereinafter referred to as "output command value") is generated. For example, when the power of the forward power flow is smaller than the first predetermined value, the measurement control unit 22 sets an output command value that reduces the AC power output from the conversion unit 72 in order to prevent the occurrence of reverse power flow. Generate. Moreover, the measurement control unit 22 generates an output command value that increases the AC power output from the conversion unit 72 when the power of the forward power flow is greater than the second predetermined value. The second predetermined value is set to a value greater than the first predetermined value. A known technique may be used for such control in the measurement control unit 22 . The measurement control unit 22 is connected to the power conditioner 70 via a communication line, and transmits an output command value to the power conditioner 70 via the communication line.

An input section 74 of the power conditioner 70 is connected to the cubicle 20 via a communication line and receives an output command value. Conversion unit 72 controls the output of AC power according to the content of the output command value received at input unit 74 . In such a configuration, the measurement control unit 22 and the watt-hour meter 30 measure the forward flow power coming from the power system 10 or the reverse power flow going out to the power system 10 . have a function. As described above, in order to suppress the expansion of the scale of facilities in the power generation system 1, it is desirable that the power generation system 1 does not include a plurality of devices having the same function.

FIG. 2 shows the configuration of the power generation system 1000. As shown in FIG. A power generation system 1000 includes a power system 100 , a cubicle 200 , a power meter 300 , a distribution board 400 , a load device 500 , a power generator 600 , a power conditioner 700 and a storage battery 800 . Cubicle 200 includes RPR 204 , and power conditioner 700 includes conversion section 702 , input section 704 and control section 706 . The power generation system 1000, like the power generation system 1 described above, is installed in a small-medium scale facility with a power receiving capacity of 50 kVA or more and 4000 kVA or less.

The electric power system 100, like the electric power system 10 described above, is a 6600 V high-voltage power provided by an electric power company or the like. As described above, the cubicle 200 has a power transformation function, performs transformation between high voltage power of 6600V and power of 100V or 200V, and has an RPR 204 for preventing reverse power flow. RPR204 is the same as the previous RPR24. Distribution board 400 is connected to cubicle 200 and connected to power grid 100 via cubicle 200 . Moreover, the distribution board 400 connects the load device 500 and supplies power to the load device 500 . The load device 500 is the same as the load device 50 described above.

The watt-hour meter 300 is a digital watt-hour meter connected to the cubicle 200, such as a smart meter. The watt-hour meter 300 has a measurement function similar to that of the watt-hour meter 30 described above, and is capable of measuring forward flow power coming from the power system 100 or reverse flow power going out to the power system 100 . be. The former corresponds to purchased power or forward flow power, and the latter corresponds to sold power or reverse flow power. That is, the watt-hour meter 300 measures the power that is bought and sold with respect to the power system 100 .

The power generation device 600 is the same as the power generation device 60 described above, and is a renewable energy power generation device such as a solar cell. Power generator 600 outputs the generated DC power to power conditioner 700 . Power conditioner 700 is arranged between power generator 600 and distribution board 400 . The conversion unit 702 has the functions of a DC-DC converter and a DC-AC inverter, converts the DC power output from the power generation device 600 into DC power of a desired voltage value, and converts the converted DC power into AC power. Convert. Conversion unit 702 outputs the converted AC power to distribution board 400 . As before, since it is assumed that the electric power is not sold but is self-consumed, the distribution board 400 supplies the AC power from the conversion unit 702 to the load device 500 .

The power meter 300 is connected to the power conditioner 700 via a communication line and communicates with the power conditioner 700 . Also, watt-hour meter 300 may be connected to power conditioner 700 via a wireless link and perform wireless communication with power conditioner 700 . The power meter 300 transmits the measurement result to the power conditioner 700 . Here, the transmission of the measurement result may be performed periodically, or may be performed when the change exceeds a predetermined range.

An input unit 704 of the power conditioner 700 is connected to the power meter 300 via a communication line or wireless line, and receives measurement results. The communication function in the input unit 704 may be configured by an optional member, and the communication device of the optional member may be connected to the power conditioner 700 .

Based on the measurement results received by the input unit 704 , the control unit 706 controls conversion by the conversion unit 702 so as not to sell power to the power system 100 . Controlling the conversion corresponds to controlling the magnitude of the AC power output from the conversion unit 702 . 3A and 3B show the data structure of tables held in the control unit 706. FIG. In the table shown in FIG. 3( a ), the control “reduce output” when the power value included in the measurement result is “power selling” and the control when the power value included in the measurement result is “power purchase” control "normal control" is shown.

Control unit 706 determines execution of normal control when the power value included in the measurement result received from conversion unit 702 is “purchased power”. As normal control, the control unit 706 performs MPPT (Maximum Power Point Tracking) control on the conversion unit 702 so that the output power of the power generation device 600 is maximized. A known technique may be used for MPPT, and control other than MPPT control may be executed as normal control. On the other hand, when the power value included in the measurement result received from conversion unit 702 is “selling power”, control unit 706 determines to reduce the output. At that time, the control unit 706 controls the conversion unit 702 so that the output AC power is 1/X times. “X” may be a predetermined fixed value, or may be a value that increases as the power value increases. In this way, the control unit 706 controls the conversion in the conversion unit 702 so that when the measurement result indicates selling power, it indicates buying power.

FIG. 3(b) is a different table from FIG. 3(a). In the table shown in FIG. 3(b), when the power value included in the measurement result is "sold", the control "charge" when the storage battery 800 can be charged and the control "charge" when the storage battery 800 can be charged. The control "reduce output" is shown when is not possible. In addition, the control “normal control” when the power value included in the measurement result is “purchased power” is also shown. Here, as shown in FIG. 2, storage battery 800 is connected to power conditioner 700 . The storage battery 800 can charge and discharge electric power, and includes a lithium ion storage battery, a nickel metal hydride storage battery, a lead storage battery, an electric double layer capacitor, a lithium ion capacitor, and the like. Storage battery 800 may be built into power conditioner 700 .

When the power value included in the measurement result received from conversion unit 702 is “purchased power”, control unit 706 determines execution of normal control and causes conversion unit 702 to operate as before. On the other hand, when the power value included in the measurement result received from the conversion unit 702 is “selling”, the control unit 706 checks the free space of the storage battery 800, and determines that charging is possible when there is free space. When the battery is fully charged, it is determined that the battery cannot be charged. If it is chargeable, control unit 706 causes storage battery 800 to be charged with DC power. If charging is not possible, the control unit 706 decides to reduce the power. At that time, the control unit 706 reduces conversion in the conversion unit 702 . When the storage battery 800 is charged, the storage battery 800 can change from a state with free capacity to a fully charged state as the battery is charged. In such a situation, control unit 706 stops charging and reduces output when storage battery 800 is fully charged.

The subject of an apparatus, system, or method in this disclosure comprises a computer. The main functions of the device, system, or method of the present disclosure are realized by the computer executing the program. A computer has a processor that operates according to a program as its main hardware configuration. Any type of processor can be used as long as it can implement functions by executing a program. The processor is composed of one or more electronic circuits including a semiconductor integrated circuit (IC) or LSI (Large Scale Integration). A plurality of electronic circuits may be integrated on one chip or may be provided on a plurality of chips. A plurality of chips may be integrated into one device, or may be provided in a plurality of devices. The program is recorded in a non-temporary recording medium such as a computer-readable ROM, optical disk, hard disk drive, or the like. The program may be pre-stored in a recording medium, or may be supplied to the recording medium via a wide area network including the Internet.

The operation of the power generation system 1000 configured as above will be described. 4(a) and 4(b) are flow charts showing processing procedures by the power generation system 1000. FIG. In FIG. 4A, the input unit 704 receives a power value (S10). If the power value indicates power selling (Y of S12), control unit 706 reduces the output from conversion unit 702 (S14). If the power value does not indicate power selling (N of S12), the control unit 706 performs normal control (S16).

In FIG. 4B, the input unit 704 receives the power value (S30). If the power value indicates power selling (Y of S32), and if the storage battery 800 can be charged (Y of S34), the control unit 706 charges the storage battery 800 (S36). If the storage battery 800 is not chargeable (N of S34), the control unit 706 reduces the output from the conversion unit 702 (S38). If the power value does not indicate power selling (N of S32), control unit 706 performs normal control (S40).

According to this embodiment, the power conditioner 700 controls the conversion in the conversion unit 702 based on the measurement result received from the watt-hour meter 300 so as not to sell the power. can. In addition, since the cubicle 200 does not need a measurement function, it is possible to suppress an increase in the scale of equipment in the power generation system 1000 . Moreover, since the power value from the watt-hour meter 300 is used, the power generation system 1000 can be configured at low cost.

In addition, since the conversion in the conversion unit 702 is controlled so that the power purchase is indicated when the measurement result indicates the power sale, the occurrence of reverse power flow can be suppressed. In addition, since the storage battery 800 is charged when the measurement result indicates that power is to be sold, the occurrence of reverse power flow can be suppressed.

A summary of one aspect of the present disclosure is as follows. A power conditioner (700) according to an aspect of the present disclosure is a power conditioner (700) disposed between a power generator (600) and a power system (100), wherein power is generated in the power generator (600). a conversion unit (702) that converts DC power into AC power; an input unit (704) that receives measurement results from a watt-hour meter (300) that measures the power that is bought and sold to the power system (100); A control unit (706) that controls conversion in the conversion unit (702) so as not to sell power based on the measurement result received by the input unit (704).

The control unit (706) may control the conversion in the conversion unit (702) so that the power purchase is indicated when the measurement result indicates the power sale.

The control unit (706) may charge the storage battery when the measurement result indicates power selling.

Yet another aspect of the present disclosure is a power generation system. This power generation system includes a power generator (600), a power conditioner (700) arranged between the power generator (600) and the power system (100), and power being traded to the power system (100). and a watt-hour meter (300) for measuring electric power. The power conditioner (700) includes a conversion unit (702) that converts DC power generated in the power generator (600) into AC power, an input unit (704) that receives measurement results from the watt-hour meter (300), A control unit (706) that controls conversion in the conversion unit (702) so as not to sell power based on the measurement result received by the input unit (704).

A storage battery connected to the power conditioner (700) may be further provided.

(Example 2)
Next, Example 2 will be described. Example 2, like Example 1, relates to a power generation system such as a solar cell system. In the first embodiment, in order to suppress the expansion of the scale of facilities in the power generation system, the power conditioner is provided with a function for determining the conversion control of the conversion unit. is input to In the second embodiment, as in the first embodiment, the power conditioner is provided with a function for determining conversion control of the conversion unit. However, in Example 2, unlike Example 1, a different value for the power value is used. Here, the description will focus on the differences from the first embodiment.

FIG. 5 shows the configuration of the power generation system 1000. As shown in FIG. A power generation system 1000 includes a power system 100 , a cubicle 200 , a power meter 300 , a distribution board 400 , a load device 500 , a power generator 600 , a power conditioner 700 , a storage battery 800 , and a current sensor 900 . Cubicle 200 includes RPR 204 , and power conditioner 700 includes conversion section 702 , input section 704 and control section 706 .

The current sensor 900 is arranged between the cubicle 200 and the distribution board 400 and is capable of measuring the forward flow current coming from the power system 100 or the reverse flow current going out to the power system 100 . The former corresponds to the purchased current or the forward current, and the latter corresponds to the sold current or the reverse current. In other words, the current sensor 900 measures the current that is bought and sold with respect to the power system 100 .

Current sensor 900 is connected to power conditioner 700 via a communication line and performs communication with power conditioner 700 . Further, current sensor 900 may be connected to power conditioner 700 via a wireless line and perform wireless communication with power conditioner 700 . Current sensor 900 transmits the measurement result to power conditioner 700 . Here, the transmission of the measurement result may be performed periodically, or may be performed when the change exceeds a predetermined range.

An input unit 704 of the power conditioner 700 is connected to the current sensor 900 via a communication line or wireless line and receives measurement results. Based on the measurement results received by the input unit 704 , the control unit 706 controls conversion by the conversion unit 702 so as not to sell power to the power system 100 . 6A and 6B show data structures of tables held in the control unit 706. FIG. In the table shown in FIG. 6( a ), the control “reduce output” when the current value included in the measurement result is “selling power” and the control “reduce output” when the current value included in the measurement result is “purchasing power” control "normal control" is shown.

When the current value included in the measurement result received from the conversion unit 702 is “purchased power”, the control unit 706 determines execution of normal control. As normal control, the control unit 706 performs MPPT control on the conversion unit 702 . On the other hand, the control unit 706 determines to reduce the output when the current value included in the measurement result received from the conversion unit 702 is “selling power”. At that time, the control unit 706 controls the conversion unit 702 so that the output AC power is 1/X times. "X" may be a predetermined fixed value, or may be a value that increases as the current value increases. In this way, the control unit 706 controls the conversion in the conversion unit 702 so that when the measurement result indicates selling power, it indicates buying power.

FIG. 6(b) is a different table from FIG. 6(a). In the table shown in FIG. 6(b), when the current value included in the measurement result is "electricity sale", the control "charge" when the storage battery 800 can be charged and the control "charge" when the storage battery 800 can be charged. The control "reduce output" is shown when is not possible. The control "normal control" when the current value included in the measurement result is "power purchase" is also shown. Here, as shown in FIG. 5, storage battery 800 is connected to power conditioner 700 .

When the current value included in the measurement result received from conversion unit 702 is “purchased power”, control unit 706 determines execution of normal control and causes conversion unit 702 to operate as before. On the other hand, when the current value included in the measurement result received from the conversion unit 702 is "selling", the control unit 706 checks the free capacity of the storage battery 800, and determines that charging is possible when there is free capacity. When the battery is fully charged, it is determined that the battery cannot be charged. If it is chargeable, control unit 706 causes storage battery 800 to be charged with DC power. If charging is not possible, the control unit 706 decides to reduce the power. At that time, the control unit 706 reduces conversion in the conversion unit 702 . When the storage battery 800 is charged, the storage battery 800 can change from a state with free capacity to a fully charged state as the battery is charged. In such a situation, control unit 706 stops charging and reduces output when storage battery 800 is fully charged.

The operation of the power generation system 1000 configured as above will be described. 7(a) and 7(b) are flow charts showing processing procedures by the power generation system 1000. FIG. In FIG. 7A, the input unit 704 receives a current value (S110). If the current value indicates power selling (Y of S112), the control unit 706 reduces the output from the conversion unit 702 (S114). If the current value does not indicate power selling (N of S112), the control unit 706 performs normal control (S116).

In FIG. 7B, the input unit 704 receives the current value (S130). When the current value indicates power selling (Y of S132), if the storage battery 800 is chargeable (Y of S134), the control unit 706 charges the storage battery 800 (S136). If the storage battery 800 is not chargeable (N of S134), the control unit 706 reduces the output from the conversion unit 702 (S138). If the current value does not indicate power selling (N of S132), the control unit 706 performs normal control (S140).

According to this embodiment, based on the measurement result received from the current sensor 900, the power conditioner 700 controls the conversion in the conversion unit 702 so as not to sell power, so the scale of the equipment in the power generation system 1000 can be expanded. can be suppressed. In addition, since the conversion in the conversion unit 702 is controlled so that the power purchase is indicated when the measurement result indicates the power sale, the occurrence of reverse power flow can be suppressed. In addition, since the storage battery 800 is charged when the measurement result indicates that power is to be sold, the occurrence of reverse power flow can be suppressed.

A summary of one aspect of the present disclosure is as follows. Another aspect of the present disclosure is also a power conditioner (700). This power conditioner (700) is a power conditioner (700) arranged between a power generator (600) and a power system (100), and converts DC power generated in the power generator (600) into AC power. In the input unit (704), a conversion unit (702) that converts to electric power, an input unit (704) that receives measurement results from a current sensor (900) that measures the current that is bought and sold to the power system (100), and the input unit (704) A control unit (706) that controls conversion in the conversion unit (702) so as not to sell power based on the received measurement result.

Yet another aspect of the present disclosure is also a power generation system. This power generation system includes a power generator (600), a power conditioner (700) arranged between the power generator (600) and the power system (100), and power being traded to the power system (100). and a current sensor (900) for measuring current. The power conditioner (700) includes a conversion unit (702) that converts DC power generated in the power generation device (600) into AC power, an input unit (704) that receives measurement results from the current sensor (900), an input A control unit (706) that controls conversion in the conversion unit (702) so as not to sell power based on the measurement result received by the unit (704).

The present disclosure has been described above based on the embodiments. It should be understood by those skilled in the art that this embodiment is an example, and that various modifications are possible in the combination of each component or each treatment process, and such modifications are within the scope of the present disclosure. .

One power conditioner 700 is included in the power generation system 1000 in the first and second embodiments. However, for example, the power generation system 1000 may include a plurality of power conditioners 700 . At that time, one of the plurality of power conditioners 700 operates as a master, and the remaining power conditioners 700 operate as slaves. A power meter 300 is connected to the power conditioner 700 of the master, and the power meter 300 outputs a power value or a current value to the power conditioner 700 of the master. Also, the master power conditioner 700 instructs the slave power conditioner 700 to operate. According to this modified example, the degree of freedom in configuration can be improved.

The control unit 706 in Examples 1 and 2 has a function of controlling the magnitude of AC power output from the conversion unit 702 . However, the present invention is not limited to this, for example, the power conditioner 700 may be provided with a display unit having a touch panel function, and enabling/disabling of functions in the conversion unit 702 may be set by the display unit. Also, an external device may be connected to the power conditioner 700, and enabling/disabling of functions in the conversion unit 702 may be set by the external device. According to this modified example, the degree of freedom in configuration can be improved.

The power conditioner 700 in Examples 1 and 2 may be connected to a retail electricity supplier's server on the Internet. In this case, the power conditioner 700 may control the output AC power in response to the remote output control command according to the magnitude of the measurement result. According to this modification, AC power can be output at 100% if power is not sold.

The power generation system 1000 in Examples 1 and 2 may include a display device connected to the power conditioner 700 . The display device displays information on the purchased power calculated based on the measurement results and the generated power. According to this modified example, the degree of freedom in configuration can be improved.

1 power generation system, 10 power system, 20 cubicle, 22 measurement control unit, 24 RPR, 30 power meter, 40 distribution board, 50 load device, 60 power generation device, 70 power conditioner, 72 conversion unit, 74 input unit, 100 power system 200 cubicle 204 RPR 300 power meter 400 distribution board 500 load device 600 power generation device 700 power conditioner 702 conversion unit 704 input unit 706 control unit 800 storage battery 1000 power generation system.

Claims (5)

A cubicle that transforms high-voltage AC power from a power system and outputs the transformed AC power , and that does not include a function for measuring the power of buying and selling power ;
a power conditioner that converts the DC power generated by the power generation device into AC power and outputs the AC power;
a distribution board connected to the cubicle and the power conditioner and supplying AC power from the cubicle or the power conditioner to a load device;
a watt-hour meter that measures the power traded to the power system and transmits the measurement result to the power conditioner;
The power conditioner is
an input unit that receives measurement results from the electricity meter;
a control unit that controls conversion from DC power to AC power so as not to sell power based on the measurement result received by the input unit;
A power generation system comprising: A cubicle that transforms high-voltage AC power from a power system and outputs the transformed AC power , and that does not include a function for measuring the power of buying and selling power ;
a power conditioner that converts the DC power generated by the power generation device into AC power and outputs the AC power;
a distribution board connected to the cubicle and the power conditioner and supplying AC power from the cubicle or the power conditioner to a load device;
a current sensor that measures a current that is bought and sold to the power system and transmits the measurement result to the power conditioner;
The power conditioner is
an input unit that receives measurement results from the current sensor;
a control unit that controls conversion from DC power to AC power so as not to sell power based on the measurement result received by the input unit;
A power generation system comprising: A cubicle that transforms high-voltage AC power from a power system and outputs the transformed AC power , and that does not include a function for measuring the power of buying and selling power ;
a main power conditioner that converts the DC power generated by the power generation device into AC power and outputs the AC power;
a slave power conditioner that converts the DC power generated by the power generation device into AC power and outputs the power;
a distribution board connected to the cubicle, the main power conditioner, and the slave power conditioner and supplying AC power from the cubicle, the main power conditioner, or the slave power conditioner to a load device;
a watt-hour meter that measures the power traded to the power system and transmits the measurement result to the main power conditioner;
The main power conditioner is
an input unit that receives measurement results from the electricity meter;
A control unit that controls conversion from DC power to AC power so as not to sell power based on the measurement result received at the input unit,
The power generation system, wherein the main power conditioner instructs the slave power conditioner to perform conversion. The control unit executes MPPT (Maximum Power Point Tracking) control when the measurement result indicates power purchase, and controls conversion so as to indicate power purchase when the measurement result indicates power sale. The power generation system according to any one of claims 1 to 3, characterized in that: Equipped with a storage battery,
The control unit executes MPPT (Maximum Power Point Tracking) control when the measurement result indicates power purchase, and executes charging of the storage battery when the measurement result indicates power sale. The power generation system according to any one of claims 1 to 3.

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