Energy Storage Converter Control for Renewable Power Curtailment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Power converter limitations in power systems lead to curtailment of excess power from renewable sources, resulting in inefficient energy generation and loss of potential energy, as they cannot handle the full power output from sources like solar or wind energy.
Innovation Solution
A system and method that utilize an energy storage power converter and controller to capture excess power from a power source, store it in an energy storage unit, and discharge it when needed, while prioritizing power from the source, using a power inverter and energy storage power converter configuration with a controller that adjusts charge and discharge commands based on power converter curtailment and source output.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If power converters are used to supply energy from renewable sources, then power conversion and grid integration is enabled, but the converters have limitations that prevent extraction of full available power resulting in curtailment and energy loss
Solution Approach 1:
The system segments the power conversion function into multiple independent converters: a power inverter for AC grid connection and a DC/DC converter for energy storage integration. This segmentation allows each converter to operate within its optimal capacity range while collectively capturing full available power from renewable sources, preventing curtailment loss.
Solution Approach 2:
The power converter system is designed with multi-functionality to handle both grid power delivery and energy storage charging/discharging operations. The DC/DC converter serves dual purposes: charging the energy storage unit from the power source and discharging to supplement the inverter output, making the system adaptable to varying power availability and grid demands.
2Productivity
If energy storage units are added to capture excess power, then energy utilization efficiency is improved, but system complexity and design requirements increase
Solution Approach 1:
The DC/DC converter acts as an intermediary component between the power source/inverter and the energy storage unit. It mediates power flow, enabling efficient energy transfer and storage while isolating the complex control requirements from the main inverter system, thus improving energy utilization without proportionally increasing overall system complexity.
3Power
If power converters operate at full capacity to maximize energy extraction, then energy generation efficiency improves, but topology limitations prevent handling full power output from renewable sources
Solution Approach 1:
The system employs dynamic power management where the DC/DC converter continuously adjusts its operation based on real-time power availability from renewable sources and current energy storage state. This dynamic adaptation allows the system to handle variable power outputs from renewable sources effectively, capturing full available power while maintaining operational flexibility.
Solution Approach 2:
The energy storage unit is pre-charged during periods of high renewable power generation when the inverter cannot handle the full output. This preliminary energy storage preparation ensures that when power demand exceeds generation or when renewable output fluctuates, the stored energy is readily available to maintain continuous full-capacity operation without curtailment.
Data Source
AI summary
A power system for connecting a power source, an energy storage unit and a grid includes a power inverter, an energy storage power converter and a controller. The power inverter is electrically coupled to the power source through a DC bus and converts DC power from the DC bus to AC power output to the grid. The power converter is electrically coupled between the DC bus and the energy storage unit and stores power in the energy storage unit and discharges power from the energy storage unit. The controller controls the power converter to store excess power from the power source that cannot be output to the grid in the energy storage unit, and control the energy storage power converter to discharge power stored in the energy storage unit to the power inverter to output to the grid.