Energy Storage Cabinet Power Switching for Black Start Cooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Energy storage cabinets in microgrids face challenges in supporting low voltage ride-through and off-grid black start scenarios due to the reliance on power from the national grid, leading to thermal runaway risks and interlock failures in air conditioning systems.
Innovation Solution
An energy storage cabinet equipped with a power converter that switches between power sources from the grid and an energy storage apparatus during normal and abnormal conditions, ensuring uninterrupted power supply to critical loads, including an air conditioning system, using a DC/DC converter with low rated power and small volume.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the air conditioning system obtains power from the power grid, then the air conditioning system can work normally during grid operation, but the air conditioning system cannot work when the power grid is abnormal (low voltage ride-through or off-grid black start)
Solution Approach 1:
The power supply loop is designed to accept multiple power sources (power grid and energy storage apparatus) and switch between them based on grid conditions. The conversion circuit can convert AC power from the grid or DC power from the energy storage apparatus into the required DC voltage for the air conditioning system, making the system universally adaptable to different power sources.
Solution Approach 2:
The conversion circuit acts as an intermediary between the power sources (grid or energy storage apparatus) and the air conditioning system. It converts both AC and DC inputs into the required DC output voltage, mediating the power transfer and enabling seamless switching between power sources without requiring separate power conversion paths.
2Reliability
If a power converter is added to enable off-grid operation, then the system can support low voltage ride-through and off-grid black start, but the device complexity and space occupation increase
Solution Approach 1:
The conversion circuit is designed to perform multiple functions: rectifying AC power from the grid, converting DC power from the energy storage apparatus, and providing the required DC output for the air conditioning system. This multi-functionality eliminates the need for separate AC-DC and DC-DC converters, reducing overall system complexity.
Solution Approach 2:
The patent merges the AC-DC rectification function and the DC-DC conversion function into a single conversion circuit. By combining these functions, the system reduces the number of separate power conversion devices needed, thereby reducing device complexity and space occupation while maintaining the ability to support both grid-connected and off-grid operations.
3Power
If the conversion circuit always converts AC to high voltage DC, then the air conditioning system can be powered during normal grid operation, but the system cannot provide power during low voltage ride-through when grid voltage is insufficient
Solution Approach 1:
The system dynamically switches between power sources based on grid voltage conditions. During normal operation, the conversion circuit converts AC power from the grid. During low voltage ride-through or off-grid conditions, the system dynamically switches to use DC power from the energy storage apparatus, adapting to changing voltage conditions to maintain power output capability.
Solution Approach 2:
The system changes the input power parameter from AC voltage (grid power) to DC voltage (energy storage power) based on grid conditions. The conversion circuit is designed to handle both AC and DC inputs, and the system switches between these different parameter states to maintain operational capability across varying voltage conditions.
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
Enables continuous operation of the air conditioning system for heat dissipation, maintaining grid connection during low voltage ride-through and off-grid black start scenarios, while minimizing space and cost overheads by integrating the power converter within existing modules.
Implementation Method 1
The power converter is configured to: convert electric energy of the energy storage apparatus into a second voltage, and provide the second voltage to the first power supply loop
Implementation Method 2
The conversion circuit is configured to: when a voltage amplitude of the power grid is greater than a specified threshold, convert an alternating current provided by the power grid into a first voltage, and provide the first voltage to the first power supply loop
Implementation Method 3
an air conditioning system for heat dissipation is also disposed in the energy storage cabinet
Data Source
AI summary
An energy storage cabinet. An additional power converter is added between an energy storage apparatus and an air conditioning system, in order to meet a power supply requirement of the air conditioning system in a case of a low voltage ride-through and an off-grid black start. In the case of the low voltage ride-through and the off-grid black start, the power converter converts electric energy of the energy storage apparatus to supply power to the air conditioning system. After a voltage of a power grid is normal or a start is completed, a conversion circuit in the air conditioning system is configured to obtain power from the power grid.