JP2018174678A - Power conversion device, power conversion system, and DC power supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power conversion device, a power conversion system, and a DC power supply device capable of reducing a measurement error.SOLUTION: A power conversion device 2 comprises an inverter circuit 220 and a controller 221. The inverter circuit 220 converts a DC power inputted from a DC line DC1 connected with a DC power supply device 3, which outputs the DC power, into an AC power. The inverter circuit 220 performs at least one of an operation of supplying the AC power to a load 5 and an operation of outputting the AC power to an AC power system 100. The controller 221 performs control of the inverter circuit 220. The controller 221 transmits noise information based on a frequency of the AC power system 100 to the DC power supply device 3 connected with the DC line DC1, by communication.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power conversion device, a power conversion system, and a DC power supply device, and more particularly to a power conversion device, a power conversion system, and a DC power supply device that convert direct current to alternating current.

  Conventionally, there has been a power control system including a power conditioner that interconnects distributed power supplies and an additional unit for adding additional power supplies (see, for example, Patent Document 1).

  The power conditioner includes a DC / DC converter that boosts or lowers the voltage of power output from the distributed power supply, an inverter that converts the output of the DC / DC converter into alternating current, a power conditioner that controls the output of the DC / DC converter and the inverter. A control unit. A system and a load are connected to the output end of the inverter, and the inverter is connected to the system and supplies power to the load.

  The additional unit includes a DC / DC converter that boosts or lowers the voltage of power output from the additional distributed power source, and an additional control unit that controls the DC / DC converter. The output terminal of the DC / DC converter of the additional unit is electrically connected to a DC intermediate link portion that is a connection point between the DC / DC converter and the inverter in the power conditioner.

  The power control unit monitors the voltage of the DC intermediate link portion, and performs PWM (Pulse Width Modulation) control of the power conditioner and the DC / DC converter of the additional unit based on the monitoring result.

JP-A-2015-122906

  In the power control system described in Patent Document 1, since the power conditioner is connected to the AC power supply system, the DC voltage applied to the DC intermediate link portion (DC line) is caused by the AC voltage of the system. Ripple noise is generated. Since the power controller performs PWM control based on the voltage monitoring result of the DC intermediate link portion, if an error occurs in the DC voltage monitoring result of the DC intermediate link portion due to ripple noise, the control of the DC / DC converter is adversely affected. There was a problem that occurred.

  The objective of this invention is providing the power converter device, power conversion system, and DC power supply device which can reduce a measurement error.

  A power converter according to one embodiment of the present invention includes an inverter circuit and a control unit. The inverter circuit converts the DC power input from a DC line connected to a DC power supply device that outputs DC power into AC power. The inverter circuit performs at least one of an operation of supplying the AC power to a load and an operation of outputting the AC power to an AC power system. The control unit controls the inverter circuit. The control unit transmits noise information based on a frequency of the AC power system by communication to the DC power supply device connected to the DC line.

  A power converter according to one embodiment of the present invention includes an inverter circuit and a control unit. The inverter circuit converts the DC power input from a DC line connected to a DC power supply device that outputs DC power into AC power. The inverter circuit performs at least one of an operation of supplying the AC power to a load and an operation of outputting the AC power to an AC power system. The control unit controls the inverter circuit. The control unit transmits information on the frequency of the AC power system through communication to the DC power supply device connected to the DC line.

  A power conversion system according to an aspect of the present invention includes the power conversion device and the DC power supply device that outputs DC power to the DC line of the power conversion device.

  A DC power supply device according to one embodiment of the present invention includes a first connection unit, a second connection unit, a converter circuit, a reception unit, and a processing unit. The first connection unit is connected to a DC power source. The second connection unit is connected to a DC line of the power conversion device. The power conversion device performs at least one of an operation of converting DC power input from the DC line into AC power and supplying the AC power to a load and outputting the AC power to an AC power system. . The converter circuit converts a voltage value of a DC voltage between the first connection portion and the second connection portion. The receiving unit receives noise information based on the frequency of the AC power system transmitted from the power converter. The processing unit determines a measurement period based on the noise information received by the receiving unit, and measures an electrical characteristic value of at least one of an input and an output of the converter circuit.

  A DC power supply device according to one embodiment of the present invention includes a first connection unit, a second connection unit, a converter circuit, a reception unit, and a processing unit. The first connection unit is connected to a DC power source. The second connection unit is connected to a DC line of the power conversion device. The power conversion device performs at least one of an operation of converting DC power input from the DC line into AC power and supplying the AC power to a load and outputting the AC power to an AC power system. . The converter circuit converts a voltage value of a DC voltage between the first connection portion and the second connection portion. The said receiving part receives the information of the frequency of the said alternating current power system transmitted from the said power converter device. The processing unit determines a measurement period based on the frequency information received by the reception unit, and measures at least one electrical characteristic value of an input and an output of the converter circuit.

  ADVANTAGE OF THE INVENTION According to this invention, the power converter device, power conversion system, and DC power supply device which can reduce a measurement error can be provided.

FIG. 1 is a system configuration diagram of a power conversion system according to an embodiment of the present invention. FIG. 2 is a system configuration diagram of a power conversion system according to Modification 1 of the embodiment of the present invention.

  The embodiment described below is only one of various embodiments of the present invention. Embodiments of the present invention are not limited to the following embodiments, and may include other embodiments. In addition, the following embodiments can be variously changed according to the design or the like as long as they do not depart from the technical idea according to the present invention.

(1) Configuration FIG. 1 is a system configuration diagram of a power conversion system 1 according to the present embodiment.

  The power conversion system 1 of this embodiment is provided in the customer facility 10 and supplies power to the load 5 in the customer facility 10 in conjunction with the AC power system 100. The power conversion system 1 can also output (reverse power flow) the power generated by the solar power generation device 11 to the AC power system 100. Here, the customer facility 10 is a facility of a customer who receives supply of energy resources from an energy resource supplier. In the present embodiment, a detached house will be described as an example of the customer facility 10.

  The power conversion system 1 includes a DC power supply device 3 that is electrically connected to the DC line DC1 of the power conversion device 2, and a power conversion device 2 that converts DC power input from the DC line DC1 into AC power. .

  A storage battery unit 12 is connected to the DC power supply device 3. The DC power supply device 3 converts the voltage value of the DC voltage input (discharged) from the storage battery unit 12 and outputs the converted voltage value to the DC line DC1. Further, the DC power supply device 3 converts the voltage value of the DC voltage input from the DC line DC1 and outputs it to the storage battery unit 12, that is, charges the storage battery unit 12.

  Next, the configuration of each part of the power conversion system 1 will be described.

(1.1) Power Conversion Device The power conversion device 2 converts a DC voltage value input from the solar power generation device 11 and outputs it to the DC line DC1, and the DC line DC1. And a DC / AC converter 22 that converts input DC power into AC power.

  The DC / DC converter circuit 21 includes a first converter circuit 211 (a converter circuit of a power conversion device), a first control processing unit 212, and a first measurement unit 213.

  The first converter circuit 211 includes, for example, a step-up type chopper circuit, converts the DC voltage input from the solar power generation device 11 into a DC voltage having a predetermined voltage value (for example, DC 300 V), and outputs the DC voltage to the DC line DC1. The first converter circuit 211 may be a conversion circuit that converts a voltage value of a DC voltage, and may be a step-down type or a step-up / down type chopper circuit.

  The first measuring unit 213, for example, a voltage dividing circuit that divides the DC voltage output from the first converter circuit 211 to the DC line DC 1, and an A / D converter that A / D converts the voltage value divided by the voltage dividing circuit. And a D converter. The first measurement unit 213 measures the output voltage of the first converter circuit 211 at a predetermined sampling interval (for example, a time interval of several mS).

  The first control processing unit 212 controls the output of the first converter circuit 211. The first control processing unit 212 includes, for example, a microcomputer having a CPU (Central Processing Unit) and a memory. The function of the first control processing unit 212 is realized by the CPU executing the program stored in the memory. The program executed by the CPU is stored in advance in a memory of a microcomputer, for example, but may be provided through an electric communication line such as the Internet or may be provided by being recorded on a recording medium such as a memory card. .

  Based on the noise information input from the system management unit 223, the first control processing unit 212 is 1 of the AC voltage of the AC power system 100 (for example, AC voltage of AC100 / 200 [V], 50/60 [Hz]). The measurement period is determined so that the period time is the measurement period. The “measurement period” here is a time length of a period in which the first control processing unit 212 calculates the average of the measurement values of the first measurement unit 213, and the first control processing unit 212 is the first measurement unit 213. The process for obtaining the average of the measured values is repeated at the period of the measurement period.

  The first control processing unit 212 obtains an average value (effective value) of the output voltage of the first converter circuit 211 by averaging the measurement values of the first measurement unit 213 in the measurement period. The measurement value of the first measurement unit 213 may include ripple noise due to the AC voltage of the AC power system 100. The frequency of the ripple noise is about twice the frequency of the AC voltage or AC current of the AC power system 100, and the first control processing unit 212 measures the measurement value of the first measurement unit 213 for one cycle of the AC voltage. Since averaging is performed over a period, measurement errors due to ripple noise can be reduced. The measurement period is not limited to the time of one cycle of the AC voltage of the AC power system 100, and may be a time (multiple positive multiple) of (1/2) cycle (half cycle) of the AC voltage. It can be changed. If the measurement period is a time multiplied by a (1/2) cycle of the AC voltage, the start time of the measurement period does not need to be synchronized with the zero cross point of the AC voltage, and the start time of the measurement period is at an arbitrary timing. Good. In addition, the first control processing unit 212 may obtain the median value of the output voltage (measured value) of the first converter circuit 211 in a measurement period that is a multiplication of the (1/2) period of the AC voltage, and is caused by ripple noise. Measurement error can be reduced.

  The first control processing unit 212 measures the output voltage based on the measurement result of the first measurement unit 213, but measures one or more of the output voltage, output current, and output power as an electrical characteristic value. May be. Further, the first control processing unit 212 may measure the output power amount in a predetermined period as an electrical characteristic value. When measuring the output current of the first converter circuit 211, the first measurement unit 213 includes a current sensor (for example, a Hall element) for measuring the current value output from the first converter circuit 211 to the DC line DC1. It only has to be. The first control processing unit 212 measures the average value of the output current by averaging the output current measured by the first measurement unit 213 for each measurement period. Further, when measuring the output power of the first converter circuit 211, the first measurement unit 213 may measure both the output current and the output voltage of the first converter circuit 211. The first control processing unit 212 calculates the output power from the output current and the output voltage measured by the first measurement unit 213, and averages the calculation result of the output power for each measurement period, thereby averaging the output power. Measure the value.

  The first control processing unit 212 continuously repeats the process of obtaining the average value (effective value) of the output voltage of the first converter circuit 211, so that the first converter circuit 211 has a predetermined voltage value. PWM control of the provided switching element is performed.

  The DC / AC converter 22 includes an inverter circuit 220 and a control unit 221.

  The inverter circuit 220 is, for example, a full-bridge inverter circuit, and converts DC power input from the DC line DC1 into AC power. The inverter circuit 220 performs at least one of an operation of connecting AC power to the AC power system 100 and supplying AC power to the load 5 and an operation of outputting AC power to the AC power system 100. The inverter circuit 220 is not limited to a full bridge type inverter circuit, and may be a half bridge type inverter circuit.

  The control unit 221 includes an inverter control processing unit 222 and a system management unit 223. The controller 221 controls the inverter circuit 220 as a whole.

  The inverter control processing unit 222 controls the output of the inverter circuit 220 based on the control signal input from the system management unit 223. For example, the inverter control processing unit 222 includes a microcomputer having a CPU and a memory. The function of the inverter control processing unit 222 is realized by the CPU executing a program stored in the memory. The program executed by the CPU is stored in advance in a memory of a microcomputer, for example, but may be provided through an electric communication line such as the Internet or may be provided by being recorded on a recording medium such as a memory card. .

  The system management unit 223 performs overall control of the power conversion system 1, and includes the first converter circuit 211, the inverter circuit 220, and the second converter circuit 31 (the converter circuit of the DC power supply device) included in the DC power supply device 3. Control the behavior. The system management unit 223 includes, for example, a microcomputer having a CPU and a memory. The function of the system management unit 223 is realized by the CPU executing a program stored in the memory. The program executed by the CPU is stored in advance in a memory of a microcomputer, for example, but may be provided through an electric communication line such as the Internet or may be provided by being recorded on a recording medium such as a memory card. . Note that the system management unit 223 and the inverter control processing unit 222 may be realized by a single microcomputer.

  Further, the system management unit 223 includes a communication unit 224 and a measurement unit 225.

  The communication unit 224 communicates with the DC power supply device 3 by wireless communication. The communication unit 224 includes a low-power wireless communication module that does not require a wireless station license. For this type of low-power radio, specifications such as the frequency band to be used and the antenna power are defined in each country depending on the application. In Japan, low power radio (specific low power radio) using radio waves such as 920 MHz band, 420 MHz band, 2.4 GHz band, and 5 GHz band is defined. Note that the communication unit 224 is not limited to a low-power wireless communication interface and can be changed as appropriate. For example, a communication interface compliant with the ZigBee (registered trademark) standard, a communication interface compliant with the Bluetooth (registered trademark) standard, or the like. But you can.

  The communication unit 224 also has a function of communicating with the first control processing unit 212 of the DC / DC converter circuit 21. Communication between the communication unit 224 and the first control processing unit 212 may be wired or wireless.

  Measurement unit 225 measures the AC voltage of AC power system 100. The measuring unit 225 includes, for example, a voltage dividing circuit that divides the AC voltage of the AC power system 100, and measures the AC voltage of the AC power system 100 from the voltage divided by the voltage dividing circuit. The measurement unit 225 may measure an alternating current of the alternating current power system 100 using a Hall IC, a current transformer, or the like, or may measure both an alternating voltage and an alternating current.

  The system management unit 223 measures the frequency (power supply frequency) of the AC power system 100 based on the frequency of the AC voltage or AC current measured by the measurement unit 225. Here, the frequency of AC power system 100 is the frequency of AC voltage or AC current of AC power system 100. Then, the system management unit 223 transmits noise information based on the frequency of the AC power system 100 from the communication unit 224 (transmission unit) to the DC power supply device 3 at a predetermined time interval (for example, 100 mS interval). Here, the noise information based on the frequency of the AC power system 100 is, for example, a measurement result of the frequency.

  Further, the system management unit 223 sends control signals for controlling the operations of the DC / DC converter circuit 21 and the DC power supply device 3 from the communication unit 224 to the first control processing unit 212 and the second control processing of the DC power supply device 3. It transmits to the part 32. The system management unit 223 receives a control signal for operating / stopping the DC / DC converter circuit 21 and the DC power supply device 3, a control signal for instructing output power of the DC / DC converter circuit 21 and the DC power supply device 3, and the like from the communication unit 224. The data is transmitted to the first control processing unit 212 and the second control processing unit 32.

  Further, the operation unit 4 such as a dip switch is connected to the system management unit 223, and data corresponding to ON / OFF of the switch is input to the system management unit 223.

(1.2) DC power supply device The DC power supply device 3 includes a first connection unit 301, a second connection unit 302, a second converter circuit 31 (converter circuit), and a second control processing unit 32 (processing unit). The 2nd measurement part 33 and the communication part 34 (reception part) are provided. The DC power supply device 3 is a charge / discharge device that charges or discharges the storage battery unit 12.

  The 1st connection part 301 is connected to the storage battery unit 12 which is DC power supply.

  The second connection unit 302 is electrically connected to the DC line DC <b> 1 of the power conversion device 2 via the electric wire 6.

  The second converter circuit 31 is, for example, a step-up / step-down bidirectional DC / DC converter, and converts the voltage value of the DC voltage between the first connection unit 301 and the second connection unit 302. When discharging from the storage battery unit 12, the second converter circuit 31 converts (boosts) the DC voltage value input from the storage battery unit 12 into a predetermined voltage value, and outputs the voltage value to the DC line DC <b> 1 via the electric wire 6. . When charging the storage battery unit 12, the second converter circuit 31 converts (steps down) a DC voltage value input from the DC line DC <b> 1 via the electric wire 6 and outputs it to the storage battery unit 12, that is, the storage battery unit 12. To charge.

  The second measurement unit 33 includes, for example, a voltage dividing circuit that divides a DC voltage output from the second converter circuit 31 to the DC line DC1 or a DC voltage input from the DC line DC1 to the second converter circuit 31, and a voltage dividing circuit. And an A / D converter that performs A / D conversion on the voltage value divided by. The second measuring unit 33 measures the output voltage of the second converter circuit 31 at a predetermined sampling interval (for example, a time interval of several mS).

  The communication unit 34 (reception unit) receives noise information transmitted from the power conversion device 2. The communication unit 34 includes a communication module having the same communication method as that of the communication unit 224 of the power conversion device 2, and performs communication with the power conversion device 2 by wireless communication.

  The second control processing unit 32 controls the output of the second converter circuit 31. The second control processing unit 32 includes, for example, a microcomputer having a CPU and a memory. The function of the second control processing unit 32 is realized by the CPU executing the program stored in the memory. The program executed by the CPU is stored in advance in a memory of a microcomputer, for example, but may be provided through an electric communication line such as the Internet or may be provided by being recorded on a recording medium such as a memory card. .

  The second control processing unit 32 is based on noise information periodically received by the communication unit 34 from the power converter 2 (in this embodiment, information on the time of one cycle of the AC voltage of the AC power system 100). The measurement period is determined at the time of one cycle of the voltage.

  The second control processing unit 32 obtains an average value (effective value) of the output voltage of the second converter circuit 31 by averaging the measurement values of the second measurement unit 33 in the measurement period. Although the measurement value of the second measurement unit 33 may include ripple noise due to the AC voltage of the AC power system 100, the second control processing unit 32 uses the measurement value of the second measurement unit 33 as the AC voltage. Therefore, measurement errors due to ripple noise can be reduced. The measurement period is not limited to the time of one cycle of the AC voltage of the AC power system 100, and may be a time multiplied by (1/2) cycle, and can be changed as appropriate. Further, if the measurement period is a time multiplied by (1/2) period, the start time of the measurement period does not need to be synchronized with the zero cross point of the AC voltage, and the start time of the measurement period may be at an arbitrary timing. . Note that the second control processing unit 32 may obtain the median value of the output voltage (measured value) of the second converter circuit 31 in a measurement period that is a multiplication of the (1/2) cycle of the AC voltage, and is caused by ripple noise. Measurement error can be reduced.

  The second control processing unit 32 measures the output voltage of the second converter circuit 31 based on the measurement result of the second measurement unit 33, but one or more of the output voltage, the output current, and the output power are measured. You may measure as an electrical characteristic value. Further, the second control processing unit 32 may measure the output power amount in a predetermined period as an electrical characteristic value. When measuring the output current of the second converter circuit 31, the second measurement unit 33 includes a current sensor (for example, a Hall element) for measuring the current value output from the second converter circuit 31 to the DC line DC1. It only has to be. The second control processing unit 32 measures the average value of the output current by averaging the output current measured by the second measuring unit 33 for each measurement period. Further, when measuring the output power of the second converter circuit 31, the second measurement unit 33 may measure both the output current and the output voltage of the second converter circuit 31. The second control processing unit 32 calculates the output power from the output current and the output voltage measured by the second measurement unit 33, and averages the calculation result of the output power every measurement period, thereby averaging the output power. Measure the value. Further, when the second converter circuit 31 charges the storage battery unit 12, the first control processing unit 212 obtains one or more of the input voltage, the input current, and the input power based on the measurement result of the first measurement unit 213. You may measure as an electrical characteristic value.

  The second control processing unit 32 performs PWM control of the switching elements included in the second converter circuit 31 so as to control the output of the second converter circuit 31 based on the measurement result of the second measurement unit 33.

(2) Operation The operation of the power conversion system 1 of the present embodiment will be described below.

  The system management unit 223 transmits a control signal from the communication unit 224 to the DC power supply device 3 and the DC / DC converter circuit 21 to control the outputs of the DC power supply device 3 and the DC / DC converter circuit 21. Further, the system management unit 223 periodically monitors the frequency of the AC power system 100 (the frequency of the AC voltage or AC current) based on the measurement result of the measurement unit 225. Then, the system management unit 223 transmits noise information based on the frequency of the AC power system 100 from the communication unit 224 to the DC power supply device 3 and the DC / DC converter circuit 21 at predetermined time intervals.

  When the first control processing unit 212 of the DC / DC converter circuit 21 receives the noise information from the system management unit 223, the measurement period is determined at the time of one cycle of the AC voltage of the AC power system 100. The first control processing unit 212 obtains an average value of the output voltage of the first converter circuit 211 by averaging the measurement results of the first measurement unit 213 for each measurement period. The first control processing unit 212 performs PWM control on the switching elements of the first converter circuit 211 so that the average value of the output voltages becomes a predetermined voltage value (for example, a voltage value instructed by the control signal). Since the first control processing unit 212 obtains the average value of the output voltage by averaging the measurement results of the first measurement unit 213 every measurement period, the measurement error due to ripple noise caused by the AC voltage can be reduced. The fluctuation of the output of the first converter circuit 211 due to the measurement error can be suppressed.

  Further, when the second control processing unit 32 of the DC power supply device 3 receives the noise information from the system management unit 223, the measurement period is determined at the time of one cycle of the AC voltage of the AC power system 100. The second control processing unit 32 obtains the average value of the output voltage of the second converter circuit 31 by averaging the measurement results of the second measurement unit 33 for each measurement period. The second control processing unit 32 performs PWM control on the switching elements of the second converter circuit 31 so that the average value of the output voltage becomes a predetermined voltage value (for example, a voltage value instructed by the control signal). Since the second control processing unit 32 obtains the average value of the output voltage by averaging the measurement results of the second measurement unit 33 for each measurement period, the measurement error due to ripple noise caused by the AC voltage can be reduced. The fluctuation of the output of the second converter circuit 31 due to the measurement error can be suppressed.

  As described above, since the system management unit 223 of the power conversion device 2 transmits noise information to the DC power supply device 3 and the DC / DC converter circuit 21 by communication, the DC power supply device 3 and the DC / DC converter circuit 21 are connected to each other. There is no need to provide a circuit for detecting the frequency of the power system 100.

(3) Modified Examples Below, power converters according to modified examples of the above embodiment are listed. In addition, each structure of the modified example demonstrated below is applicable in combination with each structure demonstrated in the said embodiment suitably.

(3.1) Modification 1
FIG. 2 is a system configuration diagram of a power conversion system 1A according to the first modification. Hereinafter, components similar to those in the above embodiment are denoted by common reference numerals and description thereof is omitted as appropriate.

  In the power conversion system 1 of the above embodiment, the power conversion device 2 includes the DC / DC converter circuit 21, but in the power conversion system 1A of the first modification, the power conversion device 2A includes only the DC / AC converter 22. . Two DC power supply devices 3 and 3A are connected to the DC line DC1 of the power conversion device 2A via electric wires 6 and 6A. A storage battery unit 12 is connected to the DC power supply device 3, and a photovoltaic power generation device 11 is connected to the DC power supply device 3A.

  The DC power supply device 3 </ b> A has the same configuration as the DC power supply device 3. The first connection unit 301A, the second connection unit 302A, the second control processing unit 32A, the second measurement unit 33A, and the communication unit 34A of the DC power supply device 3A are respectively connected to the first connection unit 301 and the second connection unit of the DC power supply device 3. This corresponds to the connection unit 302, the second control processing unit 32, the second measurement unit 33, and the communication unit 34, and a description thereof will be omitted. Further, the second converter circuit 31A of the DC power supply device 3A is the same as the second converter circuit 31 of the DC power supply device 3 except that only one-way voltage conversion is performed, and thus the description thereof is omitted.

  In the first modification, DC power supply devices 3 and 3A that convert a DC voltage input from a DC power source into a DC voltage having a predetermined voltage value and a power conversion device 2A that includes only the DC / AC converter 22 are modularized. Yes. Desired DC power supply devices 3 and 3A can be connected to the DC line DC1 of the power conversion device 2A, and the power conversion device 2A converts DC power input from the DC power supply devices 3 and 3A into AC power.

  In Modification 1, two DC power supply devices 3 and 3A are connected to the power conversion device 2A. However, one DC power supply device may be connected to the power conversion device 2A, or three or more DC power supplies may be connected. The source device may be connected at.

(3.2) Modification 2
In the said embodiment and the modification 1, although the measurement part 225 of the power converters 2 and 2A measures the frequency of the alternating current power grid | system 100, a frequency may be input using the operation part 4. FIG.

  The operation unit 4 is, for example, a dip switch. If the value of a predetermined bit is “0”, the frequency is 50 Hz, and if the value of the predetermined bit is “1”, the frequency is 60 Hz.

  The system management unit 223 reads the bit value from the operation unit 4 and determines whether the frequency of the AC voltage of the AC power system 100 is 50 Hz or 60 Hz from the bit value.

  Then, the system management unit 223 transmits information based on the frequency of the AC power system 100 from the communication unit 224 to the DC power supply device 3 by communication. In the second modification, the system management unit 223 may transmit noise information from the communication unit 224 to the DC power supply device 3 when the power is turned on and when the setting is changed by the operation unit 4. Compared to communication traffic can be reduced.

(3.3) Other Modifications In the above embodiment and Modifications 1 and 2, the system management unit 223 uses the measurement result of the frequency measured by the measurement unit 225 as noise information based on the frequency of the AC power system 100. Although it is transmitting, noise information is not limited to this. In Japan, the frequency of the AC power system 100 (hereinafter referred to as system fundamental frequency) is either 50 Hz or 60 Hz. Therefore, the system management unit 223 may transmit the system fundamental frequency (50 Hz or 60 Hz) determined from the measurement result of the measurement unit 225 as noise information from the communication unit 224 to the DC power supply device 3 by communication. For example, when the measurement result of the measurement unit 225 is 50.01 Hz, the system management unit 223 may determine that the system fundamental frequency is 50 Hz and transmit a value of 50 as noise information. In addition, the system management unit 223 uses “0” when the system fundamental frequency determined from the measurement result of the measurement unit 225 is 50 Hz and “1” when it is 60 Hz as noise information from the communication unit 224 to the DC power supply device 3. It may be transmitted and the amount of data can be reduced. Further, the system management unit 223 uses the frequency of one cycle of alternating current of the system fundamental frequency determined from the measurement result of the measuring unit 225 or time of multiplication of (1/2) period of alternating current of the system fundamental frequency based on the frequency. The noise information may be transmitted from the communication unit 224 to the DC power supply device 3.

  The power converter 2 transmits noise information based on the frequency of the AC power system 100 from the communication unit 224 to the DC power supply device 3 and the DC / DC converter circuit 21 at predetermined time intervals. The transmission may be performed only when the DC / DC converter circuit 21 is initially operated.

  The communication unit 224 transmits noise information to the DC power supply device 3 and the DC / DC converter circuit 21 by wireless communication, but the communication method is not limited to wireless communication, and may be wired communication. In the case of wired communication, the communication unit 224 may perform communication using, for example, a power line carrier communication method, or may perform communication via a dedicated communication line.

  In the said embodiment and the modification 1, 2, although the solar power generation device 11 which is a power generation device and the stationary storage battery unit 12 were illustrated as DC power supply, DC power supply is fuel cells, a wind power generator, etc. A power generation device or a storage battery of an electric vehicle may be used. The electric vehicle is, for example, a hybrid vehicle, a plug-in hybrid vehicle, an electric vehicle, or the like.

  In the above embodiment and Modifications 1 and 2, the DC power supply devices 3 and 3A and the DC / DC converter circuit 21 obtain the frequency of the AC power system 100 from the ripple noise superimposed on the DC voltage of the DC line DC1, The measurement period may be determined from the result. If DC power supply devices 3 and 3A and DC / DC converter circuit 21 can detect the frequency of AC power system 100 from ripple noise superimposed on the DC voltage of DC line DC1, it is necessary to transmit noise information from power conversion devices 2 and 2A. Communication traffic can be reduced.

  Although the case where the customer facility 10 is a detached house has been described in the above embodiment and the first and second modifications, the customer facility 10 may be a dwelling unit of a collective housing, or a tenant of an office building or a commercial building.

(Summary)
As described above, the power converter (2, 2A) of the first aspect includes the inverter circuit (220) and the control unit (221). The inverter circuit (220) converts DC power input from the DC line (DC1) into AC power. A DC power supply (3, 3A) that outputs DC power is connected to the DC line (DC1). The inverter circuit (220) performs at least one of an operation of supplying AC power to the load (5) and an operation of outputting AC power to the AC power system (100). The control unit (221) transmits noise information based on the frequency of the AC power system (100) to the DC power supply (3, 3A) connected to the DC line (DC1) by communication.

  According to this configuration, the DC power supply (3, 3A) is caused by the AC voltage of the AC power system (100) based on the noise information transmitted by communication from the power converter (2, 2A). The frequency of the generated ripple noise can be grasped. Therefore, in the DC power supply device (3, 3A), processing for reducing ripple noise can be performed, and thereby measurement errors can be reduced.

  The power converter (2, 2A) according to the second aspect is the measurement according to the first aspect, in which the frequency of the AC power system (100) is measured from at least one of the AC voltage and the AC current of the AC power system (100). A part (225) is further provided. The control unit (221) transmits noise information based on the frequency obtained from the measurement result of the measurement unit (225) to the DC power supply device (3, 3A).

  According to this configuration, even when the frequency of the ripple noise varies due to the variation in the frequency of the AC power system 100, the variation in the frequency of the ripple noise can be grasped in the DC power supply device (3, 3A).

  The power converter device (2, 2A) of the third aspect further includes an operation unit (4) for inputting the frequency of the AC power system (100) in the first aspect. The control unit (221) transmits noise information based on the frequency set by the operation unit (4) to the DC power supply device (3, 3A).

  According to this structure, the measurement part which measures the frequency of AC power system (100) becomes unnecessary.

  In the power converter device (2, 2A) of the fourth aspect, in any one of the first to third aspects, the DC power supply device (3, 3A) determines the measurement period based on the noise information. The DC power supply (3, 3A) measures at least one electrical characteristic value of an input from the DC line (DC1) and an output to the DC line (DC1) for each measurement period.

  According to this configuration, the DC power supply device (3, 3A) determines the measurement period based on the noise information transmitted from the power converter (2, 2A) by communication, and the electrical characteristic value for each measurement period. Ripple noise can be reduced.

  In any one of the first to fourth aspects, the power converter (2) according to the fifth aspect converts the DC voltage input from the DC power source (11, 12) into a DC voltage having a predetermined voltage value. A converter circuit (211) for outputting to the line (DC1) is further provided.

  According to this configuration, DC power is supplied from the DC power supply (11) connected to the converter circuit (211) and the DC power supply (12, 11) connected to the DC power supply device (3, 3A). be able to.

  About the structure which concerns on a 2nd-5th aspect, it is not a structure essential to a power converter device (2, 2A), and can be abbreviate | omitted suitably.

  The power converter device (2, 2A) of the sixth aspect includes an inverter circuit (220) and a control unit (221). The inverter circuit (220) converts DC power input from the DC line (DC1) into AC power. A DC power supply (3, 3A) that outputs DC power is connected to the DC line (DC1). The inverter circuit (220) performs at least one of an operation of supplying AC power to the load (5) and an operation of outputting AC power to the AC power system (100). The control unit (221) transmits information on the frequency of the AC power system (100) by communication to the DC power supply (3, 3A) connected to the DC line (DC1).

  According to this configuration, the DC power supply (3, 3A) is caused by the AC voltage of the AC power system (100) based on the frequency information transmitted from the power converter (2, 2A) by communication. The frequency of ripple noise generated can be grasped. Therefore, in the DC power supply device (3, 3A), processing for reducing ripple noise can be performed, and thereby measurement errors can be reduced. In addition, the information on the frequency of the AC power system (100) is not limited to the information on the frequency, but may be information on the cycle that is the reciprocal of the frequency.

  The power conversion system (1, 1A) according to the seventh aspect includes the power conversion device (2, 2A) according to any one of the first to sixth aspects and the DC line (DC1) of the power conversion device (2, 2A). And a DC power supply device (3, 3A) for outputting DC power.

  According to this configuration, measurement errors in the DC power supply (3, 3A) can be reduced.

  The DC power supply device (3, 3A) according to the eighth aspect includes a first connection unit (301, 301A), a second connection unit (302, 302A), a converter circuit (31, 31A), and a reception unit (34). , 34A) and a processing unit (32, 32A). The first connection part (301, 301A) is connected to the DC power supply (11, 12). The second connection unit (302, 302A) is connected to the DC line (DC1) of the power converter (2, 2A). The power converter (2, 2A) converts the DC power input from the DC line (DC1) into AC power and supplies AC power to the load (5) and AC power to the AC power system (100). At least one of the operations of outputting. The converter circuit (31, 31A) converts a DC voltage value between the first connection part (301, 301A) and the second connection part (302, 302A). The receiver (34, 34A) receives noise information based on the frequency of the AC power system (100) transmitted from the power converter (2, 2A). The processing unit (32, 32A) determines the measurement period based on the information received by the receiving unit (34, 34A), and determines at least one electrical characteristic value of the input and output of the converter circuit (31, 31A). measure.

  According to this configuration, measurement errors in the DC power supply (3, 3A) can be reduced.

  The DC power supply device (3, 3A) of the ninth aspect includes a first connection unit (301, 301A), a second connection unit (302, 302A), a converter circuit (31, 31A), and a reception unit (34). , 34A) and a processing unit (32, 32A). The first connection part (301, 301A) is connected to the DC power supply (11, 12). The second connection unit (302, 302A) is connected to the DC line (DC1) of the power converter (2, 2A). The power converter (2, 2A) converts the DC power input from the DC line (DC1) into AC power and supplies AC power to the load (5) and AC power to the AC power system (100). At least one of the operations of outputting. The converter circuit (31, 31A) converts a DC voltage value between the first connection part (301, 301A) and the second connection part (302, 302A). The receiving unit (34, 34A) receives information on the frequency of the AC power system (100) transmitted from the power converter (2, 2A). The processing unit (32, 32A) determines the measurement period based on the frequency information received by the receiving unit (34, 34A), and at least one electrical characteristic of the input and output of the converter circuit (31, 31A). Measure the value.

  According to this configuration, measurement errors in the DC power supply (3, 3A) can be reduced.

  In the DC power supply device (3, 3A) of the tenth aspect, in the eighth or ninth aspect, the DC power supply (11, 12) is any of the power generation device (11) and the storage battery (12) that generate DC power. It is.

  According to this configuration, a desired DC power supply can be connected and used.

  The configuration according to the tenth aspect is not an essential configuration for the DC power supply (3, 3A) and can be omitted as appropriate.

DESCRIPTION OF SYMBOLS 1,1A Power conversion system 2,2A Power converter 3,3A DC power supply 4 Operation part 5 Load 11 Solar power generation device (DC power supply)
12 Storage battery unit (DC power supply)
31, 31A Second converter circuit (converter circuit of DC power supply device)
32, 32A Second control processing unit (processing unit)
34, 34A Communication unit (receiving unit)
100 AC power system 211 First converter circuit (converter circuit of power converter)
220 Inverter circuit 221 Control unit 222 Inverter control processing unit 223 System management unit 224 Communication unit 225 Measurement unit 301, 301A First connection unit 302, 302A Second connection unit DC1 DC line

Claims (10)

An operation of converting the DC power input from a DC line connected to a DC power supply device that outputs DC power into AC power, supplying the AC power to a load, and outputting the AC power to an AC power system An inverter circuit that performs at least one of
A control unit for controlling the inverter circuit,
The said control part transmits the noise information based on the frequency of the said alternating current power system by communication to the said DC power supply device connected to the said DC track. Power converter device. A measuring unit that measures the frequency of the AC power system from at least one of the AC voltage and AC current of the AC power system;
The power conversion device according to claim 1, wherein the control unit transmits the noise information based on the frequency obtained from a measurement result of the measurement unit to the DC power supply device by communication. An operation unit for inputting the frequency of the AC power system is further provided,
The power conversion device according to claim 1, wherein the control unit transmits the noise information based on the frequency set by the operation unit to the DC power supply device by communication. The DC power supply device determines a measurement period based on the noise information, and measures at least one electrical characteristic value of an input from the DC line and an output to the DC line for each measurement period. The power converter device of any one of 1-3. The power converter according to any one of claims 1 to 4, further comprising a converter circuit that converts a DC voltage input from a DC power source into a DC voltage having a predetermined voltage value and outputs the DC voltage to the DC line. An operation of converting the DC power input from a DC line connected to a DC power supply device that outputs DC power into AC power, supplying the AC power to a load, and outputting the AC power to an AC power system An inverter circuit that performs at least one of
A control unit for controlling the inverter circuit,
The said control part transmits the information of the frequency of the said alternating current power system by communication to the said DC power supply device connected to the said DC track. Power converter device. The power conversion device according to any one of claims 1 to 6,
The DC power supply device that outputs the DC power to the DC line of the power conversion device. A power conversion system. A first connection connected to a DC power source;
For the DC line of the power converter that performs at least one of the operation of converting the DC power input from the DC line into AC power and supplying the AC power to a load and the operation of outputting the AC power to an AC power system A second connecting portion to be connected;
A converter circuit for converting a voltage value of a DC voltage between the first connection part and the second connection part;
A receiver that receives noise information based on the frequency of the AC power system transmitted from the power converter;
A DC power supply device comprising: a processing unit that determines a measurement period based on the noise information received by the reception unit and measures at least one electrical characteristic value of an input and an output of the converter circuit. A first connection connected to a DC power source;
For the DC line of the power converter that performs at least one of the operation of converting the DC power input from the DC line into AC power and supplying the AC power to a load and the operation of outputting the AC power to an AC power system A second connecting portion to be connected;
A converter circuit for converting a voltage value of a DC voltage between the first connection part and the second connection part;
A receiver for receiving information on the frequency of the AC power system transmitted from the power converter;
A DC power supply device comprising: a processing unit that determines a measurement period based on the frequency information received by the receiving unit and measures at least one electrical characteristic value of an input and an output of the converter circuit. The DC power supply according to claim 8 or 9, wherein the DC power supply is one of a power generation device and a storage battery that generate DC power.

Images