Abstract: When a measuring system for a solar battery is operated and controlled by one execution program, the execution program is roughly divided into a program portion corresponding to measurement of a sunshine time in one day and a program portion corresponding to measurement for several to about 20 years. In this case, even a small error in part of the program may stop the entire measuring system. To prevent this, the program is divided into an execution program for acquiring data, an execution program for generating information to be displayed, on the basis of the acquired data, and an execution program for recording the acquired data in a recording medium. Interprocess communication is used to exchange data between the execution programs.

Abstract: The object is to reliably detect a ground fault of a solar battery. To detect a ground fault position to take an efficient measure against the ground fault, DC power input from a solar battery is converted into AC power and supplied to a system. In a system interconnection inverter (utility connected inverter) having non-insulated input and output, the input voltage of a converter circuit and/or the intermediate voltage between the converter circuit and an inverter circuit are varied to control the potential to ground at each portion of the solar battery to a value other than a value close to zero.

Abstract: In a solar power generation system which causes a non-insulated type inverter to convert DC power generated by a solar battery into AC power and outputs the AC power to a commercial power system, in detecting a ground fault, the differential current between the output lines of the solar battery is detected, an AC leakage current component due to the capacitance to ground of the solar battery is removed from the differential current, and it is determined whether a ground fault state has occurred by comparing a current value after removal of the AC leakage current component with a predetermined threshold value. With this arrangement, a false ground fault state determination that is caused by the influence of the AC leakage current component due to the electrostatic capacitance although the DC current path can be prevented, and a ground fault state can accurately be determined.

Abstract: Along with the expansion of the application range of solar power generation systems, connection to a single-phase 100-V system is required. To most easily meet this requirement, a non-insulated inverter with a single-phase two-wire 100-V output is used. It is preferable to use an inverter with a single-phase two-wire 200-V output, i.e., a most popular commercially available inverter. For this purpose, a power supplied from a solar battery is converted into a single-phase three-wire 200-V AC power form by the inverter. The output from the inverter with non-insulated inputs and outputs is supplied to a system through a transformer arranged to connect the line of the single-phase three-wire 200-V AC power to a single-phase two-wire 100-V system with one line grounded. To make a ground fault sensor incorporated in the inverter function, the median potential line of the single-phase three-wire 200-V AC power is connected to the ground line of the system.

Abstract: A manufacturing method for manufacturing a solar panel including a solar cell and an outer housing and an inspection method for inspecting a solar panel generating system, include a step of performing one of a withstand voltage test and an insulation resistance test between a live electrical section electrically connected to the solar cell and a conductor section of the outer housing, and thereafter a step of applying a voltage between the live electrical section and the conductor section. In this way, a residual charge left subsequent to the withstand voltage test or the insulation resistance test is reliably removed within a short period of time.

Abstract: The temperature of a bypass diode of a solar cell module is measured by a temperature detector from the exterior of the solar cell module, and the results of temperature detection of each bypass diode are mutually compared to detect the presence or absence of failure in the solar cell module. Also at least one solar cell in the solar cell module is covered with a light shielding plate, then a current flowing in the bypass diode bypassing to the covered solar cell is detected, and a failed solar cell module is detected from the result of the current detection. Also the solar cell module is provided with a temperature detector capable of detecting the temperature of the bypass diode and the temperature of an internal portion of the solar cell module other than the bypass diode. In this way, it is possible to detect a failure in the solar cell module easily and precisely, and also to detect short circuit failure in the solar cell.

Abstract: In a solar power generation system having an inverter, if a smoothing capacitor in the inverter degrades, the operation of the inverter is interrupted, and a loss in the amount of power generation occurs inevitably. To prevent this loss, a degradation determination section (211) and output suppressing section (212) are provided in an inverter (2). If the degradation determination section (211) determines a degradation in capacitor (24), the operation of the inverter (2) is continued while suppressing the output current of the inverter (2) by the output suppressing section (212). In addition, a warning section (213) warns the user about the degradation in capacitor (24). With this arrangement, a solar power generation system capable of detecting a degradation in smoothing capacitor in the inverter (2) and appropriately operating the inverter (2) can be provided.

Abstract: In a power supply system for converting the output of a DC power supply having an earth capacitance to AC power, an input voltage from an input-voltage detector and an intermediate voltage from an intermediate-voltage detector are input to an input-ripple controller. The latter calculates the difference between ripple voltages of the two voltages. The input-ripple controller adjusts the size of a ripple command value, which indicates the ripple current that is to be input to a converter circuit, so as to null the difference between the ripple voltages. Furthermore, using a ripple reference waveform having a DC level, the input-ripple controller generates a ripple current waveform so as to null the average value of a full-wave rectified waveform synchronized to the output of an inverter circuit, and outputs the generated ripple current waveform to an output calculator.

Abstract: In a power generation system including a DC power supply which is connected to a low-voltage distribution system to which a plurality of consumers, each having an earth leakage breaker, are connected and one wire of which is grounded, via a receiving-end earth leakage breaker, and which includes at least a transformerless inverter and an earth floating capacitance, an operational time limit of the receiving-end earth leakage breaker of the power generation system is set to a value larger than an operational time limit of the earth leakage breakers provided in the consumers. The system also includes a ground-direction determination device for determining whether a grounded position is inside or outside the power generation system. Thus, a power generation system in which an unnecessary disconnection of electric power supply does not occur when an accident of external grounding has occurred.

Abstract: When a ground fault occurs in some solar battery string, this solar battery string may be disconnected and operation of a solar power generation system may be continued. If the open-circuit voltage of the solar battery string is high, a safety problem arises. If the open-circuit voltage is decreased, the conversion efficiency decreases. Therefore, an intermediate switch is provided midway along the solar battery string. When a ground fault occurs, this solar battery string where the ground fault has occurred is divided into substrings.

Abstract: As the application range of solar power generation systems widens, a number of relatively compact and lightweight inverters must be installed outdoors. However, an inverter has no burglarproof function at all. A burglarproof device which switches the state of the burglarproof function upon receiving a burglarproof function state change signal, and outputs an alarm signal when the output signal output in the alarm state from a connection detection section indicates that the power supply or load is disconnected is added to the inverter.

Abstract: In a power generation system including a DC power supply which is connected to a low-voltage distribution system to which a plurality of consumers, each having an earth leakage breaker, are connected and one wire of which is grounded, via a receiving-end earth leakage breaker, and which includes at least a transformerless inverter and an earth floating capacitance, an operational time limit of the receiving-end earth leakage breaker of the power generation system is set to a value larger than an operational time limit of the earth leakage breakers provided in the consumers. The system also includes a ground-direction determination device for determining whether a grounded position is inside or outside the power generation system. Thus, a power generation system in which an unnecessary disconnection of electric power supply does not occur when an accident of external grounding has occurred.

Abstract: In a power generation system including a DC power supply which is connected to a low-voltage distribution system to which a plurality of consumers, each having an earth leakage breaker, are connected and one wire of which is grounded, via a receiving-end earth leakage breaker, and which includes at least a transformerless inverter and an earth floating capacitance, an operational time limit of the receiving-end earth leakage breaker of the power generation system is set to a value larger than an operational time limit of the earth leakage breakers provided in the consumers. The system also includes a ground-direction determination device for determining whether a grounded position is inside or outside the power generation system. Thus, a power generation system in which an unnecessary disconnection of electric power supply does not occur when an accident of external grounding has occurred.

Abstract: In the present invention, the temperature of a bypass diode of a solar cell module is measured by a temperature detection means from the exterior of the solar cell module, and the results of temperature detection on each bypass diode are mutually compared to detect the presence or absence of the failure in the solar cell module. Also at least one solar cell in the solar cell module is covered with a light shielding plate, then a current flowing in the bypass diode bypassing to the covered solar cell is detected, and a failed solar cell module is detected from the result of the current detection. Also the solar cell module is provided with a temperature detection means capable of detecting the temperature of the bypass diode and the temperature of an internal portion of the solar cell module other than the bypass diode. By these, it is rendered possible to detect a failure in the solar cell module easily and exactly, and also to detect the short circuit failure in the solar cell.

Abstract: The temperature of a bypass diode of a solar cell module is measured by a temperature detector from the exterior of the solar cell module, and the results of temperature detection of each bypass diode are mutually compared to detect the presence or absence of failure in the solar cell module. Also at least one solar cell in the solar cell module is covered with a light shielding plate, then a current flowing in the bypass diode bypassing to the covered solar cell is detected, and a failed solar cell module is detected from the result of the current detection. Also the solar cell module is provided with a temperature detector capable of detecting the temperature of the bypass diode and the temperature of an internal portion of the solar cell module other than the bypass diode. In this way, it is possible to detect a failure in the solar cell module easily and precisely, and also to detect short circuit failure in the solar cell.

Abstract: In a power supply system for converting the output of a DC power supply having an earth capacitance to AC power, an input voltage from an input-voltage detector and an intermediate voltage from an intermediate-voltage detector are input to an input-ripple controller. The latter calculates the difference between ripple voltages of the two voltages. The input-ripple controller adjusts the size of a ripple command value, which indicates the ripple current that is to be input to a converter circuit, so as to null the difference between the ripple voltages. Furthermore, using a ripple reference waveform having a DC level, the input-ripple controller generates a ripple current waveform so as to null the average value of a full-wave rectified waveform synchronized to the output of an inverter circuit, and outputs the generated ripple current waveform to an output calculator.

Abstract: In a solar power generation system which causes a non-insulated type inverter to convert DC power generated by a solar battery into AC power and outputs the AC power to a commercial power system, in detecting a ground fault, the differential current between the output lines of the solar battery is detected, an AC leakage current component due to the capacitance to ground of the solar battery is removed from the differential current, and it is determined whether a ground fault state has occurred by comparing a current value after removal of the AC leakage current component with a predetermined threshold value. With this arrangement, a false ground fault state determination that is caused by the influence of the AC leakage current component due to the electrostatic capacitance although the DC current path can be prevented, and a ground fault state can accurately be determined.

Abstract: Along with the expansion of the application range of solar power generation systems, connection to a single-phase 100-V system is required. To most easily meet this requirement, a non-insulated inverter with a single-phase two-wire 100-V output is used. It is preferable to use an inverter with a single-phase two-wire 200-V output, i.e., a most popular commercially available inverter. For this purpose, a power supplied from a solar battery is converted into a single-phase three-wire 200-V AC power form by the inverter. The output from the inverter with non-insulated inputs and outputs is supplied to a system through a transformer arranged to connect the line of the single-phase three-wire 200-V AC power to a single-phase two-wire 100-V system with one line grounded. To make a ground fault sensor incorporated in the inverter function, the median potential line of the single-phase three-wire 200-V AC power is connected to the ground line of the system.

Abstract: In a solar power generation system having an inverter, if a smoothing capacitor in the inverter degrades, the operation of the inverter is interrupted, and a loss in the amount of power generation occurs inevitably. To prevent this loss, a degradation determination section (211) and output suppressing section (212) are provided in an inverter (2). If the degradation determination section (211) determines a degradation in capacitor (24), the operation of the inverter (2) is continued while suppressing the output current of the inverter (2) by the output suppressing section (212). In addition, a warning section (213) warns the user about the degradation in capacitor (24). With this arrangement, a solar power generation system capable of detecting a degradation in smoothing capacitor in the inverter (2) and appropriately operating the inverter (2) can be provided.

Abstract: As the application range of solar power generation systems widens, a number of relatively compact and lightweight inverters must be installed outdoors. However, an inverter has no burglarproof function at all. A burglarproof device which switches the state of the burglarproof function upon receiving a burglarproof function state change signal, and outputs an alarm signal when the output signal output in the alarm state from a connection detection section indicates that the power supply or load is disconnected is added to the inverter.