Generation power detection device for photovoltaic element string

Abstract

The invention provides a generation power detection device for a photovoltaic element string. The device mainly comprises a photovoltaic element string, a switch, a detection loop capacitor, a detection loop resistor, an isolation diode, a voltage maintaining capacitor and a high-input-impedance operational amplifier. The photovoltaic element string is configured to charge the detection loop capacitor when the switch is turned on. The charging current flows through the detection loop resistor and the isolation diode to charge the voltage maintaining capacitor. The voltage applied across the two ends of the voltage maintaining capacitor is approximately equal to the voltage applied across the two ends of the detection loop resistor. Due to the extremely high input resistance of the high-input-impedance operational amplifier and the isolation effect of the one-way conduction of the isolation diode, the voltage applied across the two ends of the voltage maintaining capacitor can be kept for a period of time. The power of the photovoltaic element string can be obtained through measuring the voltage applied to the output end of the high-input-impedance operational amplifier. The deviceis small in average access power, high in measurement precision, simple in structure, reliable in work and low in manufacturing cost.

Description

Technical field [0001] The invention belongs to the field of solar energy applications, and specifically relates to a detection device that needs to detect the power generation power of a photovoltaic module string in the power generation process at any time. Background technique [0002] The self-powered tracking bracket that carries the photovoltaic module string in the automatic solar tracking power generation device that tracks the sun. In the morning and evening when the light is low, the power generation of the photovoltaic module string will drop a lot. There may be insufficient power supply. Motor, when the controller is connected to the drive motor, the power supply voltage of the controller will drop a lot, causing the controller to fail to work and sometimes self-excitation. Therefore, it is necessary to check the power generation of the photovoltaic module string at any time. When the power is enough to drive the drive motor, the controller is connected to the drive m...

AI Technical Summary

Problems solved by technology

[0002] The self-powered tracking bracket that carries the photovoltaic module string in the automatic sun-tracking power generation device that tracks the sun will drop a lot in the morning and evening when the power generation of the photovoltaic module string is low, and the power supply may be insufficient, and the controller of the self-powered tracking bracket may not be able to drag the drive Motor, when the controller is connected to the drive motor, the power supply voltage of the controller will drop a lot, so that the controller cannot work normally and sometimes self-excitation occurs. Therefore, it is necessary to detect the power generation of the photovoltaic module string at any time. When the power is enough to drive the drive motor, the controller is then connected to the drive motor. Since the current device for detecting the power generation of the photovoltaic module string consumes a lot of power, it should detect the power generation of the photovoltaic module string when the power consumption is large in the morning and evening when the light is weak. When the device is connected to the photovoltaic module string, the power supply voltage of the controller will drop a lot, so that the controller cannot work normally, and the power generated by the photovoltaic module string cannot be detected.

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