EV Charging Window Control for Grid Overload Response
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for controlling the charging of a group of vehicles fail to effectively interrupt the charging processes of a large number of vehicles in response to power grid overloads without affecting departure times or increasing costs.
Innovation Solution
A central control system adjusts the charging time windows for vehicles to include an additional period before the original window, ensuring the same departure time and charge level are maintained while reducing costs, allowing more vehicles to suspend charging when needed.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If charging processes of vehicles are interrupted to reduce power consumption in the electricity grid, then power reduction is achieved, but the number of vehicles that can have their charging interrupted is limited due to departure time constraints
Solution Approach 1:
The patent applies preliminary action by advancing the charging time window for vehicles before the originally scheduled charging period. This allows the charging process to start earlier, creating a buffer that enables interruption during peak load periods while still completing charging before departure. The control system proactively shifts charging schedules in advance rather than reacting to grid conditions, thereby resolving the contradiction between achieving power reduction and maximizing the number of interruptible vehicles.
2Productivity
If charging time windows are advanced to enable more charging interruptions, then more vehicles can comply with grid reduction requests, but charging costs may increase due to less optimal charging times
Solution Approach 1:
The patent applies dynamics by making the charging time window flexible and adjustable based on grid conditions. The control system dynamically modifies the charging schedule, advancing the time window only when and to the extent necessary to enable grid load reduction. This dynamic adjustment optimizes the balance between enabling charging interruptions and maintaining cost-effectiveness, rather than using a fixed advanced schedule for all vehicles.
Solution Approach 2:
The patent applies parameter changes by modifying the charging time window parameters (start time, duration) based on grid load conditions and vehicle departure requirements. The control system adjusts these parameters to find the optimal balance point where charging can be interrupted when needed while minimizing cost increases, thereby resolving the contradiction between productivity and energy loss.
3Loss of energy
If charging is suspended for vehicles to reduce grid power consumption, then grid overload is compensated, but departure times specified by vehicle users may be affected
Solution Approach 1:
The patent applies preliminary action by calculating and setting the advanced charging time window such that charging completion is guaranteed before the user-specified departure time. The control system proactively determines the maximum advance period that still allows sufficient charging time, thereby ensuring departure time compliance is maintained even when charging is later interrupted for grid load reduction.
Solution Approach 2:
The patent applies feedback by continuously monitoring the charging status, time elapsed, and remaining charge requirements to ensure that interrupting charging during the advanced window will not prevent timely completion before departure. This feedback mechanism ensures that grid load reduction actions do not compromise user-specified departure times, resolving the contradiction between energy loss reduction and reliability maintenance.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a method for controlling the electric charging of a group of vehicles (1). A central control system (CO) can communicate with the respective vehicles (1) of the group and with a server (SE') of the network operator. In each case a charging time window (LF), a departure time (AZ) and a setpoint state of charge (SL) of the vehicle-side energy store at the departure time (AZ) are defined in advance for one or more specific vehicles (1). In addition, a cost value (KW) for the charging time window (LF) is predefined in accordance with a cost function which specifies a cost level as a function of the charging process according to the charging time window (LF). The central control system (CO) transmits a modified charging time window (LF') to a respective specific vehicle (1) of at least some of the specific vehicles (1), after which the charging process is carried out according to the modified charging time window (LF') by fulfilling the charging time criterion with an unchanged departure time (AZ) and setpoint state of charge. The modified charging time window (LF') comprises at least one time period which occurs before the start of the non-modified charging time window (LF), wherein the cost value (KW) according to the cost function for the modified charging time window (LF') is precisely as high as or is lower than the cost value (KW) for the non-modified charging time window (LF).