PV Module Protective Circuit with Energy Store for Reliable Shading Operation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing protective circuits for photovoltaic (PV) modules often fail to reliably supply electrical power, especially during extreme shading or maintenance situations, leading to potential power losses and safety hazards due to the reliance on the connected PV module for energy supply.
Innovation Solution
A protective circuit design that includes a series circuit with a diode and energy store connected in parallel with the input, allowing for charging of the energy store via both input and output terminals, ensuring continuous operation and disconnection of the PV module in safety situations, while minimizing component count and cost.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the protective circuit relies on the connected PV module for energy supply, then the component outlay can be minimized, but the reliability of electrical supply fails during extreme shading or maintenance situations
Solution Approach 1:
The energy store is charged in advance from the PV module during normal operating conditions so that electrical energy is available when the PV module becomes unavailable due to shading or maintenance. This preliminary energy storage action ensures the protective circuit remains operational without requiring additional power supply components.
Solution Approach 2:
The protective circuit serves itself by using the PV module's own output to charge the energy store during normal operation. The system uses its own operational state to prepare for future failure states, eliminating the need for external power supplies or complex backup systems.
2Ease of manufacture
If the protective circuit is designed with minimal components, then the cost-effectiveness is improved, but the ability to ensure continuous operation during shading situations deteriorates
Solution Approach 1:
The energy store accumulates electrical energy in advance during normal PV module operation, enabling the protective circuit to maintain functionality during subsequent shading events without requiring complex redundant systems or additional components that would increase manufacturing cost.
Solution Approach 2:
The energy store serves multiple functions: it provides backup power during shading, enables controller operation during maintenance, and allows the protective circuit to remain functional under various operating conditions. This multi-functionality eliminates the need for separate systems for each scenario.
3Reliability
If the PV module is disconnected in safety situations, then safety is improved, but the controller may fail due to lack of power supply
Solution Approach 1:
The energy store is charged in advance from the PV module during normal operation, ensuring that when disconnection is required for safety reasons, the controller continues to receive power from the pre-charged energy store rather than from the disconnected PV module.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution ensures reliable electrical supply to the protective circuit in various PV module states, including shading and maintenance, and effectively disconnects the PV module in safety situations, preventing energy emission and maintaining safe voltage levels.
Implementation Method 1
a series circuit comprising a first diode and an energy store, wherein the series circuit is arranged in parallel with the input of the protective circuit
Implementation Method 2
a series circuit comprising a first diode and an energy store, wherein the series circuit is arranged in parallel with the input of the protective circuit
Data Source
AI summary
The disclosure relates to a protective circuit for a photovoltaic (PV) module that includes an input having two input terminals for connecting the PV module, an output having two output terminals for connecting further PV modules of a series circuit comprising PV modules, a first switch for connecting one of the input terminals to one of the output terminals, and a controller configured to control the first switch, wherein the protective circuit further includes a series circuit including a first diode and an energy store, wherein the series circuit is arranged in parallel with the input of the protective circuit. The protective circuit also includes a second diode, which connects an output terminal of the protective circuit to a midpoint of the series circuit including the first diode and the energy store, and wherein a series circuit including the second diode and the energy store is connected in parallel with the first switch. The disclosure also relates to a method for operating a protective circuit according to the disclosure, and to a photovoltaic (PV) system including a series circuit comprising PV modules.