JP2015089145A - Power conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power conditioner which allows for easy specification whether or not reduction of the amount of power generation is due to deterioration of the power conditioner.SOLUTION: A control unit 6 of a power conditioner 2 calculates the conversion efficiency of the power conditioner 2 based on the input power and output power thereof, and stores the maximum value of conversion efficiency thus calculated every predetermined period. The fact whether or not the conversion efficiency of the power conditioner has lowered can be grasped quickly and exactly, by comparably displaying the maximum value of conversion efficiency thus stored in an up-to-date predetermined period, and the maximum value of conversion efficiency in an earlier predetermined period on a display section 12 for maintenance.

Description

  The present invention relates to a power conditioner, and more particularly to a power conditioner that converts DC power output from a power generation unit into AC power that can be linked to a power system in a power generation system such as a solar power generation system.

  In recent years, residential solar power generation systems have attracted attention as an effective use of renewable energy.

  As is well known, a solar power generation system is a power generation system that includes a solar cell panel (solar cell module) as a power generation unit, and uses a power conditioner that is a power converter to convert DC power generated by the solar cell panel. It is converted into AC power that can be connected to the grid and linked to the power grid.

  By the way, if the power conditioner used in such a solar power generation system deteriorates, the conversion efficiency decreases. However, if there is no abnormality in the operation of the power conditioner, the power conditioner operates without notifying the abnormality. continue.

  However, continuing the operation of the power conditioner in a state where the conversion efficiency is low is accompanied by a decrease in the amount of power to be supplied, which is not preferable for consumers.

  For this reason, it has been proposed to store the maximum power generation amount for each predetermined period in the power conditioner with respect to the decrease in the power generation amount, and perform failure diagnosis of the photovoltaic power generation system based on those stored values (for example, Patent Document 1).

JP2012-114108A

  However, the decrease in the amount of power generation is also affected by the situation of the solar panel (for example, the degree of deterioration over time), the amount of solar radiation, and the temperature. It is difficult to determine whether there is a problem with the inverter (that is, the power conditioner has deteriorated or failed) or due to other factors (for example, aging of the solar panel).

  Therefore, even if a repair request is made due to a decrease in the amount of power generation, it is difficult for a repair worker to identify the cause of the decrease in the amount of power generation.

  The present invention has been made in view of such conventional problems, and the object of the present invention is to easily identify whether the cause of the decrease in power generation is due to deterioration of the power conditioner. Is to provide a simple power conditioner.

  In order to achieve the above object, a power conditioner according to claim 1 of the present invention includes input power detection means for detecting input power to the power conditioner, and output power for detecting output power from the power conditioner. A detection means, an efficiency calculation means for calculating the conversion efficiency of the power conditioner based on the input power detected by the input power detection means and the output power detected by the output power detection means, and the efficiency calculation means Maximum value storage means for storing the maximum value of the calculated conversion efficiency for each predetermined period, the maximum value of the conversion efficiency in the latest predetermined period stored in the maximum value storage means, and the conversion efficiency in the predetermined period before that An informing means for informing the maximum value in a comparable manner is provided.

  In the power conditioner according to claim 1, the maximum value of the conversion efficiency of the power conditioner is stored for each predetermined period, and the maximum value of the conversion efficiency in the latest predetermined period and the conversion in the previous predetermined period by the notification means. Since the maximum value of the efficiency is reported in a comparable manner, it is possible to quickly and accurately grasp whether or not the conversion efficiency of the power conditioner is reduced due to deterioration or failure of the power conditioner.

  The power conditioner according to claim 2 is the power conditioner according to claim 1, wherein the notifying unit is configured to provide a maximum conversion efficiency in the latest predetermined period and a maximum conversion efficiency in the previous predetermined period. It is characterized by comprising a display device for displaying values.

  In the power conditioner according to claim 2, regarding the conversion efficiency of the power conditioner, the maximum value of the conversion efficiency in the latest predetermined period and the maximum value of the conversion efficiency in the previous predetermined period are displayed on the display device. Therefore, a repair worker or the like can quickly and accurately grasp whether or not the conversion efficiency of the power conditioner is reduced and the degree of the reduction by comparing and confirming the displayed conversion efficiencies.

  Note that the notification by the notification means is not limited to the display by the display device, but when performing display using the display device, the maximum value of the conversion efficiency in the latest predetermined period and the maximum value of the conversion efficiency in the previous predetermined period are Both can be displayed alternately, both can be displayed simultaneously, or both can be selectively displayed according to the operator's operation. In addition, a result of comparison between the two (for example, how much the maximum value of the conversion efficiency in the latest predetermined period is compared to the maximum value of the conversion efficiency in the previous predetermined period) is displayed. It is also possible.

  The power conditioner according to claim 3 is notified when the notification means notifies the maximum value of the conversion efficiency stored in the maximum value storage means in the power conditioner according to claim 1. The maximum input power and the average input voltage for a predetermined period corresponding to the maximum value of the conversion efficiency are reported.

  In the power conditioner according to the third aspect, when the notifying means notifies the maximum value of the conversion efficiency stored in the maximum value storing means, the predetermined value corresponding to the maximum value of the conversion efficiency together with the maximum value of the conversion efficiency. Since the maximum input power and the input voltage average value during the period are notified, if the amount of power generation is reduced due to a factor other than the deterioration / failure of the power conditioner, this can be accurately grasped.

  The power conditioner according to claim 4 is the power conditioner according to any one of claims 1 to 3, wherein the maximum value of the conversion efficiency in the latest predetermined period and the maximum value of the conversion efficiency in the predetermined period before that. Efficiency comparison means for comparing values, and as a result of comparison in the efficiency comparison means, the maximum value of conversion efficiency in the latest predetermined period is less than a predetermined ratio with respect to the maximum value of conversion efficiency in the previous predetermined period. And an abnormality determining means for determining that the conversion efficiency of the power conditioner has been reduced.

  In the power conditioner according to claim 4, based on the result of comparison by the efficiency comparison means for comparing the maximum value of the conversion efficiency in the latest predetermined period and the maximum value of the conversion efficiency in the previous predetermined period, Since the abnormality determination means determines the presence or absence of an abnormality due to a decrease in conversion efficiency of the power conditioner, the repair operator can easily grasp the presence or absence of the abnormality of the power conditioner based on the determination result.

  According to the power conditioner according to the present invention, the maximum value of the conversion efficiency of the power conditioner is stored for each predetermined period, and the maximum value of the conversion efficiency in the latest predetermined period and the maximum value of the conversion efficiency in the previous predetermined period. Therefore, when the conversion efficiency of the power conditioner is reduced due to deterioration or failure of the power conditioner, it is possible to quickly and accurately grasp the decrease. Therefore, according to the present invention, it is possible to easily determine whether or not the cause of the decrease in the power generation amount is mainly due to deterioration or failure of the power conditioner.

It is a circuit diagram which shows schematic structure of the solar energy power generation system using the power conditioner which concerns on this invention. It is a flowchart which shows an example of the procedure which produces | generates the data of the maximum value of conversion efficiency in the same power conditioner. It is a flowchart which shows an example of the procedure which produces | generates the data of the maximum input electric power and input voltage average value in the power conditioner.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Embodiment 1
FIG. 1 shows a schematic configuration of a power generation system (solar power generation system) using a power conditioner according to the present invention. The solar power generation system shown in FIG. 1 includes a solar cell panel 1, a power conditioner 2, and a power system 3 as main parts.

  As is well known, the solar cell panel 1 is a power generation device (power generation unit) using a solar cell (solar cell) that converts light energy into DC power. This solar cell panel 1 is installed on a sunny place, for example, on the roof of a house.

  The power conditioner 2 is a power conversion device (system-connected inverter device) for converting DC power generated by the solar battery panel 1 into AC power that can be connected to a power system 3 such as a commercial power system. The power conditioner 2 includes a converter 4, an inverter 5, and a control unit 6 as main parts.

  The converter 4 is composed of a DC / DC converter circuit that boosts the voltage of the DC power generated by the solar cell panel 1. Inverter 5 is formed of a DC / AC inverter circuit that converts the DC power boosted by converter 4 into predetermined AC power (for example, single-phase three-wire AC 100/200 V). The AC power output from the inverter 5 is connected to the power system 3 through interconnection.

  The control unit 6 is a control device that mainly controls the converter 4 and the inverter 5 and includes a microcomputer (not shown) as the control center. This microcomputer includes a control program for controlling the converter 4 and the inverter 5. In connection with the control of converter 4 and inverter 5, control unit 6 includes input voltage sensor 7 that measures the input voltage from solar panel 1, input current sensor 8 that measures the input current, and power conditioner 2. Output voltage sensor 9 for measuring the output voltage from the output and output current sensor 10 for measuring the output current, the input power based on the input voltage and the input current, the output power based on the output voltage and the output current Each is configured to calculate and detect. That is, the control unit 6 functions as input power detection means for detecting input power to the power conditioner 2 and output power detection means for detecting output power from the power conditioner 2.

  In addition to the control of the converter 4 and the inverter 5, the control unit 6 has a function of monitoring, for example, the operating condition of the power conditioner 2 and storing / holding data as a monitoring result. Thus, when a transition is made to a maintenance operation mode, which will be described later, the stored / held data can be displayed on the maintenance display unit 12. Therefore, the control unit 6 includes a storage device (not shown) (for example, a RAM or a non-volatile memory) for storing various data.

  In the power conditioner 2 shown in the present embodiment, the control unit 6 uses the data storage / retention function to calculate the conversion efficiency of the power conditioner 2 based on the input power and the output power. Based on the calculation result, the control unit 6 stores and holds the maximum value of the conversion efficiency in the storage device every predetermined period. That is, the control unit 6 of the power conditioner 2 shown in the present embodiment also functions as an efficiency calculating means for calculating the conversion efficiency of the power conditioner 2 and a maximum value storing means for storing the maximum value of the conversion efficiency. (These details will be described later).

  Reference numeral 11 denotes a maintenance operation unit used when a repair worker or the like performs maintenance of the power conditioner 2, and 12 denotes a maintenance display unit.

  Unlike the operation unit (not shown) operated by the customer, the maintenance operation unit 11 is an operation unit mainly used by repair workers, and the power conditioner 2 is operated by the operation of the operation unit 11. The controller 6 can be changed from the normal operation mode to the maintenance operation mode, and various operations related to maintenance of the power conditioner 2 can be performed, such as selecting items displayed on the maintenance display unit 12. It has become. In addition, this operation part 11 is arrange | positioned in the position which a consumer does not operate, such as the inner side of the decorative panel (not shown) of the front of the power conditioner 2, for example.

  The maintenance display unit (display device) 12 is a display unit mainly used by repair workers, similar to the maintenance operation unit 11. As the display unit 12, for example, several digits (for example, A 6-segment) 7-segment display is used. Then, information necessary for maintenance such as the state of the power conditioner 2 and data stored in the control unit 7 is displayed using several digits and symbols displayed on the display unit 12. Yes. The display unit 12 is also arranged inside the decorative panel of the power conditioner 2 in the same manner as the operation unit 11 for maintenance. However, the display unit 12 can be seen from the outside of the decorative panel by providing a transparent window on the decorative panel. It may be configured as follows.

  Next, generation and use of data related to the maximum value of the conversion efficiency in the control unit 6 of the power conditioner 2 will be described.

  In the power conditioner 2 shown in the present embodiment, as described above, the control unit 6 is configured to calculate the conversion efficiency of the power conditioner 2 based on the input power and the output power. The control unit 6 performs the following processing. In the processing described below, the control unit 6 performs processing while appropriately storing the calculated result in the storage device of the control unit 6. FIG. 2 shows a procedure for generating data of the maximum value of the conversion efficiency in the control unit 6.

(A) The control unit 6 calculates the conversion efficiency every first predetermined time T1 (100 msec in this embodiment), and integrates the calculation results (see steps S2 and S3 in FIG. 2). That is, the control unit 6 performs the following calculation (1) in this process.
Σ conversion efficiency [%] = Σ (output power [W] ÷ input power [W] × 100) (1)

  Here, if the amount of power generated by the solar battery panel 1 is small, the operation of the inverter 5 becomes unstable due to the minimum output, and accurate conversion efficiency cannot be calculated. It is desirable to set a lower limit value, and if it falls below this lower limit value, it is desirable not to use the calculation result at that time or to replace it with a fixed value set in advance. In addition, when performing the process of this numerical formula (1), the control part 6 resets the result calculated previously, and starts a calculation (refer FIG. 2 step S1).

(B) Then, when the preset second predetermined time T2 (1 minute in the present embodiment) elapses during the processing of (a), the control unit 6 calculates the interval conversion efficiency A (FIG. Step). (See S4). This section conversion efficiency A is obtained by the following formula (2).
Section conversion efficiency A [%] = Σ conversion efficiency [%] ÷ number of integrations (2)

  Here, the second predetermined time T2 is set to 1 minute because the amount of energy stored in the DC link capacitor 13 (see FIG. 1) of the inverter 5 fluctuates when the power generation amount of the solar cell panel 1 is small. Since the efficiency fluctuates, an average is taken in a section of about 1 minute.

(C) When the section conversion efficiency A is calculated, the control unit 6 compares the calculated section conversion efficiency A with the section maximum conversion efficiency (current section maximum conversion efficiency) B on the current day, and calculates the calculated section. If the conversion efficiency A is greater than the current day section maximum conversion efficiency B, the calculated section conversion efficiency A is stored as the current day section maximum conversion efficiency B (see steps S5 and S6 in FIG. 2). That is, when the following formula (3) is established, the control unit 6 sets the calculated section conversion efficiency A as the current section maximum conversion efficiency B.
Maximum conversion efficiency on the day B [%] <section conversion efficiency A [%] (3)

  That is, the control unit 6 updates the current day maximum conversion efficiency B every minute.

(D) Then, when a preset third predetermined time T3 (1 day: 24 hours in the present embodiment) elapses during the process of (c), the control unit 6 determines that the current day interval maximum conversion efficiency B and If the current day section maximum conversion efficiency B is larger than the current month section maximum conversion efficiency C by comparing with the section maximum conversion efficiency (current month section maximum conversion efficiency) C in the current month, the current day section maximum conversion efficiency B is This is stored as C (see steps S7 to S9 in FIG. 2). That is, when the following formula (4) is established, the control unit 6 sets the current day section maximum conversion efficiency B as the current month section maximum conversion efficiency C.
Maximum conversion efficiency C [%] for the current month section <Maximum conversion efficiency B [%] for the current day section (4)

  That is, the control unit 6 updates the current month section maximum conversion efficiency C every day. After this comparison, the control unit 6 initializes (resets) the current day section maximum conversion efficiency B (see step S10 in FIG. 2).

(E) Then, when a predetermined period T (30 days in this embodiment) elapses, the control unit 6 replaces the current month section maximum conversion efficiency C with the last month section maximum conversion efficiency D at that time, The maximum conversion efficiency C for the current month is initialized (steps S11 to S13 in FIG. 2).

  Here, the reason why the predetermined period T is set to 30 days is that one month is calculated in 30 days in order to generate data of the section maximum conversion efficiency for each month. As described later, since one month is treated as 30 days, the last month interval maximum conversion efficiency D is used as data for comparison with the current conversion efficiency. This is because there is no need to make months.

  In creating the maximum conversion efficiency data for each month, in this embodiment, the control unit 6 adds a counter for the number of days every day, and changes monthly when the count value reaches 30. As shown in FIG. 2, the process of step S12 in FIG. 2 is performed.

  Thus, the data of the last month section maximum conversion efficiency D and the current conversion efficiency (for example, current month section maximum conversion efficiency C) generated in this way can be obtained by operating the operation unit 11 for maintenance by a repair worker. It is displayed on the display unit 12 for maintenance so that it can be compared.

  That is, for example, by the predetermined operation of the operation unit 11, the last month section maximum conversion efficiency D and the current month section maximum conversion efficiency C are alternately displayed, or both are displayed side by side, or according to the operation of the operator. For example, the two can be displayed selectively so that the repair worker can compare the two.

  Thus, according to the power conditioner 2 shown in this embodiment, the maximum value of the conversion efficiency of the power conditioner 2 is stored every predetermined period T, and the maximum value of the conversion efficiency in the latest predetermined period is displayed by the display unit 12. And the maximum value of the conversion efficiency in a predetermined period before that are displayed in a comparable manner. When the power generation amount is reduced, the repair worker confirms the display on the display unit 12 to reduce the power generation amount. It is possible to quickly and accurately grasp whether or not it is due to deterioration or failure of the power conditioner 2.

  That is, the repair worker compares the current month section maximum conversion efficiency C displayed on the display unit 12 with the last month section maximum conversion efficiency D, and determines that the current month section maximum conversion efficiency C is more abnormal than the last month section maximum conversion efficiency D. If it is reduced to a level that can be considered (for example, 80% or less of the maximum conversion efficiency D last month), it is determined that the decrease in the amount of power generation is due to an abnormality or failure of the power conditioner 2. Can do.

  In this display, if the predetermined period T has not elapsed since the installation of the power conditioner 2, the data for the maximum conversion efficiency D for the last month has not been generated. It is desirable to perform alternative processing such as displaying efficiency C and maximum conversion efficiency B for the current day in a comparable manner.

  In the present embodiment, the case where both the current month section maximum conversion efficiency C and the last month section maximum conversion efficiency D are displayed on the display unit 12 has been described. For example, the control unit 6 has a function of comparing both (efficiency comparison means). ), And the result of comparing the two (for example, the ratio of the current month section maximum conversion efficiency C to the last month section maximum conversion efficiency D and the difference between the two) can be displayed. In this case, the repair worker can easily grasp the presence or absence of abnormality of the power conditioner based on the comparison result.

  When the control unit 6 compares the current month section maximum conversion efficiency C and the last month section maximum conversion efficiency D in this way, the control unit 6 determines whether the power conditioner 2 is abnormal or faulty based on the result. (Abnormality determination means) is provided, and when the ratio of the current month section maximum conversion efficiency C to the last month section maximum conversion efficiency D is equal to or less than a predetermined ratio (for example, 80%), the control unit 6 controls the power conditioner 2. It is also possible to determine that the conversion efficiency is abnormally lowered and to notify the fact through the display unit 12 or the like.

Embodiment 2
Next, a second embodiment of the power conditioner 2 according to the present invention will be described with reference to FIG.

  In the power conditioner 2 shown in the second embodiment, the control unit 6 monitors and stores input power and input voltage from the solar battery panel 1 in addition to monitoring and storing conversion efficiency by the control unit 6. It is configured to display on the unit 12. Since the other points are common to the above-described first embodiment, the same reference numerals are given to the parts having the same configuration, and the description will be omitted.

  In the power conditioner 2 shown in this embodiment, in addition to the generation of data related to the maximum value of the conversion efficiency shown in Embodiment 1 described above, the control unit 6 performs the maximum input power and input voltage average value by the following procedure. Is configured to monitor and memorize. FIG. 3 shows the procedure.

  That is, the control unit 6 measures input power (power generation amount of the solar cell panel 1) and input voltage from the solar cell panel 1 every predetermined time T4 (1 second in this embodiment) (see step S1 in FIG. 3). The average value is calculated every predetermined time T5 (1 minute in this embodiment) (see step S2 in FIG. 3). That is, the input power and the input voltage are integrated every second, and the average value is calculated by dividing by the number of integrations.

  When the average value of the input power and the input voltage is calculated in this way, the control unit 6 compares the calculated input power with the maximum input power of the day (the maximum power of the day), and calculates the calculated input power. If (that is, the power generation amount of the solar panel 1) is larger than the maximum power on the day, the calculated input power is stored as the maximum power on the day, and the average value of the input voltages measured at the same time is also stored (FIG. 3). (See steps S3 and S4). In other words, the maximum value of the day and the average value of its input voltage are updated every minute.

  Then, when a predetermined time T6 (one day: 24 hours in the present embodiment) elapses, the maximum power on the day is compared with the maximum power on the current month (maximum power on the current month), and the maximum power on the current day is greater than the maximum power on the current month. The maximum power of the day is stored as the maximum power of the current month (see steps S5 to S7 in FIG. 3). At that time, the average value of the input voltage stored together with the maximum power on that day is also stored together.

  Then, when the predetermined period T7 (30 days in the present embodiment) has elapsed, the control unit 6 stores the current month's maximum power as the last month's maximum power at that time (see steps S9 and S10 in FIG. 3). Here, in this embodiment, since the maximum power per month is stored for one year, the last month's maximum power is stored individually for 12 months. In this embodiment, one month is calculated on the 30th, and the counter of the number of days is added when the day has passed, and when the count value reaches 30, it is processed as a monthly change (step in FIG. 3). (See S9 and S11). That is, the day count value is initialized. Then, a new month counter is added.

  Thus, when the data of the maximum power for 12 months and the average value of the input voltage at that time are accumulated, the control unit 6 compares these and extracts the month with the largest maximum power ( 3 (see step S12 in FIG. 3), the average value of the maximum power and input voltage of the month is stored as the maximum power generation monthly power and the same month voltage in the most recent year (see step S13 in FIG. 3).

  In addition, in the process of step S13 in FIG. 3, when it is within one year since the installation of the power conditioner 2, the maximum power of the month with the largest maximum power and the average value of the input voltage are set up to date. The maximum amount of power generated in one year is stored as the monthly power and the same month voltage (steps S14 and S15 in FIG. 3).

  Thus, the data of the maximum power generation amount monthly power (maximum input power) and the same month voltage (input voltage average value) generated in this way is used for maintenance by operating the operation unit 11 for maintenance by a repair worker. Can be displayed on the display unit 12. Therefore, when the power generation amount decreases, the repair worker displays the maximum power generation amount monthly power and the average value of the input voltage of the month, the current input power and the input voltage on the display unit 12, and compares them. By doing this, it is possible to quickly and accurately grasp whether or not the solar cell panel 1 has an abnormality or failure.

  In particular, these displays and the display of the maximum value of the conversion efficiency shown in the first embodiment are displayed in combination (specifically, the maximum input power and the input voltage in a predetermined period corresponding to the maximum value of the conversion efficiency to be displayed). By displaying the average value etc.), the repair worker can easily grasp whether the decrease in the amount of power generation is due to the abnormality / failure of the power conditioner 2 or the abnormality / failure of the solar panel 1 Will be able to.

  The above-described embodiment shows a preferred embodiment of the present invention, and the present invention is not limited to this, and various design changes can be made within the scope of the invention.

  For example, in the above-described embodiment, the case where the display unit 12 for maintenance is used as a notification unit for notifying the maximum value of the conversion efficiency has been shown. It is also possible to configure to display on a monitor device used for this purpose. These notifications are not limited to display, and a voice message or the like can be used in combination with display or instead of display.

  Moreover, although the case where this invention was used for the solar power generation system was shown in embodiment mentioned above, the power conditioner which concerns on this invention is used for electric power generation parts (for example, wind power generator etc.) other than the solar cell panel 1. FIG. It is also possible to apply.

  Note that the predetermined time and the predetermined period shown in the above-described embodiment are merely examples for explaining the present invention, and can be appropriately changed.

DESCRIPTION OF SYMBOLS 1 Solar cell panel 2 Power conditioner 3 Electric power system 4 Converter 5 Inverter 6 Control part 7 Input voltage sensor 8 Input current sensor 9 Output voltage sensor 10 Output current sensor 11 Operation part 12 for maintenance 12 Display part for maintenance (notification means)

Claims (4)

Input power detection means for detecting input power to the inverter,
Output power detection means for detecting output power from the power conditioner;
Efficiency calculating means for calculating the conversion efficiency of the power conditioner based on the input power detected by the input power detecting means and the output power detected by the output power detecting means;
Maximum value storage means for storing the maximum value of the conversion efficiency calculated by the efficiency calculation means for each predetermined period;
Power comprising: a notifying means for reporting the maximum value of the conversion efficiency in the latest predetermined period stored in the maximum value storage means and the maximum value of the conversion efficiency in the previous predetermined period in a comparable manner. Conditioner.   The said alerting | reporting means is comprised by the display apparatus which displays the maximum value of the conversion efficiency in the said latest predetermined period, and the maximum value of the conversion efficiency in the said predetermined period before that. Power conditioner.   When the notification means notifies the maximum value of the conversion efficiency stored in the maximum value storage means, the notification means notifies the maximum input power and the input voltage average value for a predetermined period corresponding to the notified maximum value of the conversion efficiency. The power conditioner according to claim 1. Efficiency comparison means for comparing the maximum value of the conversion efficiency in the latest predetermined period with the maximum value of the conversion efficiency in the previous predetermined period;
As a result of the comparison in the efficiency comparing means, when the maximum value of the conversion efficiency in the latest predetermined period becomes equal to or less than a predetermined ratio with respect to the maximum value of the conversion efficiency in the previous predetermined period, the conversion efficiency of the power conditioner is The power conditioner according to any one of claims 1 to 3, further comprising an abnormality determination unit that determines that the voltage is lowered.

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