Inverter Power Management for PV Derating and Export Limits
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Inverters connected to photovoltaic systems face inefficiencies due to derating conditions that restrict power output to match household load consumption, leading to wasted energy and reduced self-consumption of surplus power, while adhering to grid feed-in regulations.
Innovation Solution
An inverter system with a processor that detects net load, analyzes power transfers, and adjusts output and controllable load consumption to maximize self-consumption of renewable energy while preventing grid exports, using a power manager to dynamically adjust power distribution based on derating states and export conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the inverter limits the output power to match household load consumption during derating conditions, then grid feed-in regulations are complied with, but the available power from the photovoltaic source is wasted and self-consumption is reduced
Solution Approach 1:
The inverter continuously monitors the actual power output from the photovoltaic source and compares it with the limited power output being supplied to the load network. This feedback mechanism enables the system to detect derating conditions and respond by increasing controllable load consumption to utilize the available power that would otherwise be wasted, while maintaining compliance with grid feed-in regulations.
Solution Approach 2:
The system uses the available photovoltaic power to serve the controllable loads directly within the load network, creating a self-consuming mechanism. By automatically increasing controllable load consumption during derating conditions, the system serves itself by utilizing its own generated power rather than exporting it to the grid or wasting it, thereby improving self-consumption and energy efficiency.
2Power
If the inverter reduces power output during derating conditions, then the output power matches load consumption limits, but the power consumed by controllable storage devices is reduced
Solution Approach 1:
The system dynamically adjusts the power consumption of controllable storage devices based on the derating state of the photovoltaic source. When derating is detected, the inverter automatically increases the power consumption of controllable loads to match the available power from the photovoltaic source. This dynamic adjustment ensures that controllable storage devices utilize maximum available power during derating conditions, converting the limitation into an opportunity for increased self-consumption.
Solution Approach 2:
The inverter changes the operational parameters of controllable storage devices by adjusting their power consumption levels. During derating conditions, the system modifies the power consumption parameter of controllable loads from a baseline level to a higher level that matches the available photovoltaic power, thereby maximizing energy utilization while maintaining system balance.
3Device complexity
If the inverter operates without awareness of available photovoltaic power during derating, then control is simplified, but the overall energy conversion efficiency is reduced
Solution Approach 1:
The inverter incorporates a feedback mechanism that provides awareness of the available photovoltaic power by continuously monitoring the actual power output from the photovoltaic source. This feedback enables the inverter to detect derating conditions and automatically adjust controllable load consumption accordingly, maximizing energy conversion efficiency without significantly increasing system complexity.
Data Source
AI summary
An inverter (200) connected to an energy source (100) and configured to supply power to a load network (300) comprising at least one controllable load, said inverter (200) comprising a processor (201) adapted to control the at least one controllable load of the load network (300) is disclosed. The processor (201) comprising: a net load detector (201a) detects a net load of the load network (300); a power export analyzer (201b) determines an inverter power transfer of the inverter and a grid power transfer of a grid (400); characterized in that a power manager (201c) varies the power output of the inverter (200) and a power consumption of the at least one controllable load based on the inverter power transfer, the grid power transfer, an export condition violation and a derating state of the energy source (100).