Energy Storage Device Primary Control Power via State of Charge Control
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Solution Overview
Problem
Conventional power grids face inefficiencies in providing primary control power, as generators must remain operational at all times, leading to unnecessary energy consumption and limitations in using electronic or electrochemical energy storage devices due to stochastic demand causing random walk effects.
Innovation Solution
A system utilizing an energy resource controller with a state of charge control unit and primary power control unit, applying a step-like state of charge response curve to an energy storage device, which adjusts based on grid parameters and electricity prices to prevent inadmissible state of charge states, enabling efficient use of energy storage devices for primary control power.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If generators are kept operational at all times to provide primary control power, then reliability of primary control power supply is improved, but energy consumption increases and efficiency deteriorates
Solution Approach 1:
The patent changes the operational parameters of the energy storage device by dynamically adjusting the state of charge (SOC) thresholds based on grid frequency conditions. When grid frequency deviates from nominal values, the SOC thresholds are adjusted to enable the energy storage device to provide primary control power only when needed, rather than requiring continuous generator operation. This parameter adaptation resolves the contradiction by enabling reliable control power provision through conditional energy storage discharge rather than continuous generation.
2Productivity
If energy storage devices are used to provide primary control power, then efficiency is improved, but inadmissible state of charge states occur due to stochastic demand
Solution Approach 1:
The patent implements a feedback mechanism where the energy resource controller continuously monitors grid frequency and the state of charge of the energy storage device. Based on this feedback, the controller dynamically adjusts the SOC thresholds and control parameters to prevent the state of charge from entering inadmissible regions. This closed-loop feedback system resolves the contradiction by maintaining reliable SOC levels while enabling efficient primary control power provision through energy storage.
Solution Approach 2:
The patent introduces dynamic adjustment of SOC thresholds based on real-time grid conditions and predicted demand patterns. Rather than using fixed SOC limits, the system adaptively modifies the acceptable SOC range according to stochastic demand variations, allowing the energy storage device to efficiently provide primary control power while preventing inadmissible SOC states. This dynamic approach resolves the contradiction between efficiency and reliability.
3Device complexity
If state of charge thresholds are fixed, then device complexity is reduced, but inability to handle stochastic demand reduces adaptability
Solution Approach 1:
The patent applies preliminary action by pre-calculating and storing multiple SOC threshold configurations corresponding to different grid frequency conditions and demand scenarios. The energy resource controller selects from these pre-determined threshold sets based on current grid conditions, avoiding the need for complex real-time optimization calculations. This approach maintains relatively simple device complexity while achieving high adaptability to stochastic demand through pre-prepared control strategies.
Data Source
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AI summary
A system for providing a primary control power (PCP) for a power grid (PG) by at least one energy storage device (ESD) comprising an energy resource controller (ERC) connected to said energy storage device (ESD), wherein said energy resource controller (ERC) has a state of charge control unit (SOC-CU) adapted to perform a state of charge (SOC) power control of the energy storage device (ESD) to avoid inadmissible state of charge states of the energy storage device (ESD) caused by a stochastic demand for primary control power (PCP) by said power grid (PG).