Potential Induced Degradation Detection in Solar Cells

A solar cell structure that enables wide-spectrum absorption through a tandem architecture. The tandem cell comprises two separate solar cells joined together through a common substrate, where each cell is optimized for a specific spectral range. The tandem architecture enables simultaneous absorption of solar radiation across a broad spectrum, making it particularly suitable for applications requiring high-efficiency solar conversion in various environmental conditions.

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Reducing photovoltaic cell degradation through controlled reverse bias voltage application during current-voltage sweeps. The method involves intermittently applying reverse bias voltage to solar cells during J-V characterization to prevent charge carrier trapping and maintain device performance. The application of reverse bias voltage during sweeps slows down degradation by de-trapping charge carriers, particularly in polymer-based solar cells like PCDTBT:PC70BM, where photo-induced defects lead to significant degradation. This approach enables the development of photovoltaic cells with improved durability and efficiency compared to conventional methods.

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Solar module aging diagnosis system and method for monitoring and predicting module failure and degradation through power generation data analysis. The system integrates power generation data from multiple modules across a solar array, comparing it against predefined threshold values and aging patterns to calculate an aging value for each module. This aging value is then compared against a reference value to determine module failure or degradation. The system enables proactive maintenance by providing early warnings of potential issues through both threshold-based and aging-based diagnostics.

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Low-cost, high-accuracy system for detecting abnormalities in solar cells like decreased power generation and hot spots. The system periodically acquires the operating voltage of a solar cell string. If the time-series variation in voltage exceeds a threshold, it indicates an abnormality in the cell string. This allows detecting cell issues without additional environmental sensors.

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A method for detecting potential degradation in solar cells through early detection of partial degradation (PD) in the solar cell's internal resistance network. The method employs a parallel resistance model of the solar cell, which is generated from measurements of the cell's AC impedance. By analyzing the model's response to partial degradation, the method identifies changes in the parallel resistance that indicate degradation. This approach enables earlier detection of PD compared to traditional methods that rely on full degradation thresholds.

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Method for testing photovoltaic cells to determine their power and failure rates. The method involves dividing the cells into segments and measuring the characteristic curves of each segment sequentially while illuminating them one at a time. The segment curves are added to determine the overall cell curve. This allows accurate testing of long cells that cannot be uniformly illuminated by conventional equipment. The segments are moved relative to the lighting device to measure them sequentially. The segments can be divided based on the area illuminated by the testing device.

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A deterioration diagnosis system for solar cell strings and photovoltaic power systems that enables precise location of deteriorated solar cells within the string. The system measures the cumulative resistance of each solar cell in the string over time, calculating a normalized resistance value for each cell. By comparing the resistance values to a predetermined threshold, the system identifies cells that have exceeded this threshold, indicating deterioration. This approach eliminates the need for manual inspection of individual solar cells, significantly reducing maintenance time and labor costs.

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A photovoltaic aging diagnosis system that accurately diagnoses the degree of deterioration of solar modules by analyzing their voltage characteristics. The system measures the average voltage value for each module over a period, calculates the average change rate of the average voltage value over that period, and calculates the average value between modules in the same string. It then compares these values against reference values to detect abnormal voltage deviations. The system enables rapid diagnosis of module failures even before the degradation calculation is performed, through its ability to identify voltage anomalies that exceed reference values.

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A photovoltaic (PV) sensor for early detection of potential induced degradation (PID) in PV systems. The sensor is specifically designed to monitor PV modules at the negative voltage end of a string, where degradation is most pronounced. The sensor operates with low power currents (typically below 10 mA) and measures shunt resistance within the PV module. It isolates the PV module during interrogation to maintain system integrity. The sensor provides real-time monitoring of shunt resistance and PV module power loss, enabling early detection of PID before significant degradation occurs.

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Real-time monitoring of photovoltaic module degradation through intelligent string-level analysis. The system measures voltage across each string and calculates daily average voltage deviations between strings. By comparing these deviations to reference values, it identifies significant voltage drops indicative of module degradation. The system provides detailed degradation metrics, enabling proactive maintenance and optimizing system performance through targeted monitoring and replacement.

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Detecting solar cell string deterioration through a novel method that leverages real-time current measurements and reference ratios. The system monitors current values across multiple strings while storing reference ratios for each string. When current values deviate below predetermined thresholds, it compares them against the stored reference ratios. If the current ratio is consistently lower than the reference ratio, it indicates cluster deterioration, triggering early detection of the affected string. This approach enables accurate identification of solar cell modules or clusters with deteriorated components, enabling proactive maintenance and reducing overall system losses.

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Method for detecting solar cell string deterioration in photovoltaic power systems. The method compares the current output of each solar cell string against a reference current level, and uses a threshold-based approach to identify potential string failures. The comparison is performed over predetermined time intervals, with the threshold being set based on the reference current level. If the current output consistently falls below the reference level, it indicates deterioration, and the method determines if the entire string is affected. This approach enables early detection of solar cell string failures through continuous monitoring rather than relying on a single measurement point.

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Solar cell with integrated monitoring of contact area between the back electric field and the back electrode. The cell incorporates a novel design where the back field and electrode contact area are dynamically monitored through integrated sensors within the cell structure. This enables real-time detection of contact area changes, enabling proactive maintenance and optimization of solar cell performance.

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Sensitive detection of solar cell defects through non-destructive analysis of photovoltaic cells. The method employs a novel optical spectroscopic technique that utilizes advanced spectroscopic imaging and machine learning algorithms to detect subtle defects in solar cells. This approach enables the detection of deep-level defects such as voids, grain boundaries, and dislocations that are challenging to identify through traditional EL methods. The technique leverages advanced spectroscopic imaging and machine learning algorithms to analyze the optical signatures of solar cells, providing detailed insights into their internal structure and defects.

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Determining the presence of aging photovoltaic module faults in a solar string system without installing individual voltage or current sensors. The method analyzes power data from the connected modules to detect abnormal power variations, specifically identifying deviations from the normal power-voltage characteristic curve. The analysis is based on a secondary derivative of the power output, which captures the aging-induced power waveform characteristics. By comparing the power output against predetermined thresholds, the system determines whether a module has reached an abnormal state.

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A method for detecting solar cell module deterioration in solar power systems while maintaining the module's electrical connection. The method measures the IV characteristics of the solar cell string under controlled lighting conditions, specifically during the operating region of the bypass diode. By analyzing the IV curve in this region, the method determines the solar cell module's deterioration status without disconnecting the module from the string. The method uses a novel approach that identifies clusters of modules as a single unit, with each cluster's IV characteristics measured separately. This approach enables efficient monitoring of multiple modules simultaneously while maintaining the module's electrical integrity.

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Diagnostic method and device for solar cell modules that enables precise monitoring of deterioration through impedance and phase angle analysis. The method employs a novel approach where the solar cell module is subjected to AC signal modulation at specific frequencies, generating a spectrum of impedance and phase angle values. By analyzing these spectral characteristics, the device calculates the equivalent circuit parameters in the light-shielded state, enabling the detection of deterioration through changes in capacitance values at specific frequency ranges. This approach provides a comprehensive diagnostic capability that can be applied across the module's lifespan, particularly when visual inspection methods are impractical or unavailable.

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Determining the functional deterioration of solar cells in series-connected arrays through a novel method that analyzes the IV characteristics of the entire array rather than individual components. The method measures the IV curve of the array at multiple voltage levels, determining the threshold voltage where the IV curve shifts from the normal operating range to the cutoff range. This threshold voltage is then compared against the IV curve of individual solar cells to identify potential failures. The method enables the simultaneous monitoring of multiple solar cells in series, enabling early detection of array-level failures without disconnecting the array.

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Inspecting solar cell modules without adding components to the existing circuitry. The method measures current flow through the solar cell module's internal circuitry to detect faults such as short circuits and open faults. This approach eliminates the need for external sensors or contact points, enabling comprehensive inspection of the solar cell array's internal circuitry without altering the device's functionality.

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Solar cell module diagnostic system for detecting defects in photovoltaic power generation systems through early detection of partial failures. The system employs a light-shielding device that selectively blocks light from specific solar cell substrates, allowing monitoring of the underlying electrical characteristics. By analyzing the light current waveform patterns during the light-shielding operation, the system identifies deviations indicative of potential defects, such as contamination or structural damage. This approach enables early detection of partial failures before their cumulative impact causes system performance degradation, while maintaining the system's operational efficiency.

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