Solar power generation system

Abstract

This invention provides a solar power generation system that ensures the open-circuit voltage does not exceed the allowable voltage limit of the power converter, even in cold weather, without changing the number of solar cell modules connected in series. [Solution] The solar power generation system S1 includes a solar cell B, an inverter circuit 1 that converts and outputs the power generated by the solar cell B, a circuit breaker 31 that can disconnect the connection between the solar cell B and the inverter circuit 1, a voltage sensor 9 that detects the output voltage output of the solar cell B, a control circuit 6 that controls the inverter circuit 1, and a voltage reduction unit E1 that can reduce the output voltage. When starting the operation of the inverter circuit 1, if the output voltage is above a threshold voltage, the control circuit 6 opens the circuit breaker 31 and activates the voltage reduction unit E1 to reduce the output voltage, then closes the circuit breaker 31 to start the inverter circuit 1, and then stops the function of the voltage reduction unit E1.

Claims

1. Solar cells and A power conversion circuit that converts and outputs the power generated by the aforementioned solar cell, A circuit breaker capable of interrupting the connection between the solar cell and the power conversion circuit, A voltage sensor for detecting the output voltage output of the aforementioned solar cell, A control circuit for controlling the power conversion circuit, A voltage reduction unit capable of reducing the output voltage, Equipped with, When the control circuit starts operating the power conversion circuit, if the output voltage is above a threshold voltage, the circuit breaker is open, the voltage reduction unit is activated to reduce the output voltage, then the circuit breaker is closed, the power conversion circuit is started, and then the function of the voltage reduction unit is stopped. Solar power generation system.

2. The voltage reduction unit consists of a circuit in which a resistive load and a switch are connected in series, which is connected in parallel to the solar cell, and functions when the switch is closed. The photovoltaic power generation system according to claim 1.

3. The voltage reduction unit includes a heater that can heat the solar cell, and functions by heating the solar cell. The photovoltaic power generation system according to claim 1.

4. The voltage reduction unit comprises a power supply connected to the solar cell, and functions by the power supply supply supplying current to the solar cell. The photovoltaic power generation system according to claim 1.

5. The control circuit, when stopping the operation of the power conversion circuit, reduces the output voltage by activating the voltage reduction unit while the circuit breaker is closed, then stops the power conversion circuit, and then opens the circuit breaker before stopping the function of the voltage reduction unit. A solar power generation system according to any one of claims 1 to 4.

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