VPP Relay Hold Control for Demand Response Charging Wear
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The frequent switching of relays in vehicles participating in demand response requests in virtual power plants leads to increased wear and tear, reducing their ability to participate effectively, particularly in V1G vehicles that can only receive power from the network.
Innovation Solution
A power management system that includes a server managing a virtual power plant, which instructs vehicles to maintain their relays in a connected state during charge processes to suppress the number of relay switches, using control mechanisms to ensure continuation times and adjust values based on charge power and historical data.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the relay is frequently switched to handle demand response requests, then the responsiveness to DR requests is improved, but the relay wear increases and reliability deteriorates
Solution Approach 1:
The system performs preliminary actions by maintaining the relay in a connected state before charge processes are completed. The server instructs the vehicle to maintain connection even after charging finishes, so that when new DR requests arrive, the relay is already in the correct state and can respond immediately without switching delays.
Solution Approach 2:
The relay connection is maintained continuously through the charge process and beyond completion. Instead of switching off immediately when charging ends, the relay remains connected to handle potential subsequent DR requests, ensuring continuous useful action and reducing the frequency of on/off cycles.
2Reliability
If the relay is maintained in connected state to reduce switching, then relay wear is reduced, but the ability to respond to new DR requests may be delayed
Solution Approach 1:
The relay is put into the connected state in advance and maintained there, so when new DR requests arrive, the system is already prepared and can respond immediately without the delay of switching operations.
3Reliability
If unconditional prohibition of switching after threshold is applied, then relay wear is suppressed, but the vehicle cannot participate in subsequent DR requests
Solution Approach 1:
The system dynamically adjusts relay control based on real-time conditions. Instead of a static threshold-based prohibition, the server continuously monitors charge processes and DR requests, instructing vehicles to maintain connection during charging and for a period afterward, optimizing both relay protection and DR participation flexibility.
Data Source
AI summary
A power management system manages power transmitted between a VPP connected to a power network installed in a predetermined area and the power network. The VPP includes vehicles each including a power storage device that is chargeable by receiving power from the power network. A server of the power management system acquires the state of a relay for each of the vehicles. When number of on times that the relay is brought from a disconnected state to a connected state is more than a first value in a case that the power storage device is charged in a target vehicle in accordance with a request for an increase in amount of power demanded in the power network, the server instructs the target vehicle to maintain the relay in the connected state until a charge process executed in accordance with the request is completed.