Energy Storage Valve Isolation for Leakage-Safe Maintenance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High-voltage direct-connected energy storage systems face challenges in maintenance safety due to residual voltage leading to leakage currents and limited fault-handling methods, resulting in low system availability during maintenance and non-severe faults.
Innovation Solution
An energy storage valve submodule with a switch module that allows electrical isolation between the power and energy storage modules, using load switches, isolating switches, and solid-state circuit breakers to disconnect and isolate the modules, ensuring safe maintenance and system availability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the main circuit is disconnected from the high-voltage bus during maintenance, then the system voltage is reduced, but the ground voltage of each submodule cannot be reduced to single-submodule level, resulting in high voltage to ground and leakage current
Solution Approach 1:
The patent divides the energy storage system into independent valve-level isolation units. Each valve can be independently isolated from the high-voltage bus through valve isolation switches, allowing maintenance personnel to work on specific valves without exposing themselves to high ground voltage from other operational submodules. This segmentation enables safe maintenance at valve level while the rest of the system remains operational.
Solution Approach 2:
The patent introduces valve isolation switches as intermediary devices between the energy storage valves and the high-voltage bus. These switches act as mediators that can disconnect individual valves from the high-voltage bus, creating an intermediate isolated state that eliminates leakage current paths while maintaining system operation. The isolation switches provide a controlled transition state that resolves the contradiction between system continuity and maintenance safety.
2Reliability
If electronic bypassing or bypass switch activation is used for fault handling, then the fault is isolated, but the system must be shut down for maintenance, resulting in low system availability
Solution Approach 1:
The patent implements valve-level isolation capability that segments the fault containment to individual valves rather than requiring system-wide shutdown. When a valve experiences a non-severe fault, only that specific valve can be isolated using its dedicated isolation switch, while other valves continue to operate normally. This segmentation transforms a system-level outage into a localized valve-level maintenance event, dramatically improving system availability during fault handling.
Solution Approach 2:
The patent introduces dynamically controllable isolation switches that enable flexible fault management. These switches can be activated or deactivated based on real-time system conditions and fault severity, allowing the system to transition between different operational states. For non-severe faults, the isolation switches enable selective valve disconnection while maintaining overall system operation, creating a dynamic response that adapts to varying fault conditions rather than requiring static system shutdown.
3Reliability
If the system is shut down for maintenance, then safety is improved, but system availability is reduced
Solution Approach 1:
The patent enables maintenance activities to be performed at the valve level rather than requiring system-wide shutdown. By isolating individual valves from the high-voltage bus using dedicated isolation switches, maintenance personnel can safely work on specific valves while other valves continue to operate. This segmentation of maintenance scope allows parallel operation of maintenance and system function, simultaneously achieving maintenance safety and system availability.
Solution Approach 2:
The patent implements preliminary isolation capability through isolation switches that can be activated before maintenance begins. By pre-isolating the specific valve to be maintained from the high-voltage bus, the system creates a safe working environment in advance without affecting other operational valves. This preliminary action ensures that safety measures are in place before maintenance personnel engage, while the rest of the system remains operational throughout the maintenance process.
Data Source
AI summary
This disclosure relates to the field of power electronics technology and provides an energy storage valve submodule, an energy storage valve, and an energy storage station. In the energy storage valve submodule, a power module can disconnect an electrical connection from an energy storage module through a switch module, forming electrical isolation, thereby achieving the electrical disconnection between the power module and the energy storage module. During maintenance of components other than the energy storage module in the energy storage valve, leakage current is prevented, ensuring the personal safety of maintenance personnel. Similarly, in the case of a non-severe fault on the energy storage module side of the energy storage valve, the switch module can be used to isolate the energy storage module from the system under the premise that the energy storage valve is locked, without affecting the safe operation of the entire system, effectively improving system availability.