Reverse Flow Power Control Using Minimum Reception Power
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge is to prevent deviations in reverse flow power conditions in renewable energy power plants, particularly when there are control delays that can lead to unintended reverse flows, potentially causing financial penalties and limiting power system capabilities.
Innovation Solution
A reverse flow power control device is implemented, which includes an input unit for accepting actual power values and minimum reception power information, a storage unit for storing this data, a calculator for calculating command values for output and load power, and an output unit for sending these commands. The calculator includes an output controller, a load controller, a command value re-calculator, and a calculation interval adjustment part to ensure that reception power remains above a minimum threshold, preventing reverse flow.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If load in plant is varied in accordance with renewable energy, then renewable energy utilization is improved, but reverse flow power may exceed output control command due to control delay
Solution Approach 1:
The control device performs preliminary calculation of the reception power value before actual power flow occurs, using predicted renewable energy output and planned load variations. This advance calculation allows the system to preemptively adjust control commands to prevent reverse flow exceeding the output control command, even accounting for control delays in the system.
Solution Approach 2:
The control device continuously monitors actual renewable energy output, actual load power, and actual reception power, comparing these against predicted values and control commands. This feedback mechanism enables real-time adjustments to control commands, ensuring that reverse flow power remains within acceptable limits despite variations in renewable energy generation and load demands.
2Reliability
If protection function is used to stop power generation when reverse flow is likely, then reverse flow prevention is achieved, but power generation restart time is extended
Solution Approach 1:
Instead of waiting for reverse flow to occur and then activating protection functions, the control device calculates predicted reception power values in advance and issues control commands before reverse flow conditions develop. This preliminary control action prevents reverse flow from occurring in the first place, eliminating the need for protection function activation and subsequent restart delays.
Solution Approach 2:
The system converts the potential harmful effect of reverse flow into a beneficial control opportunity by using the prediction and calculation mechanisms to adjust load power and renewable energy output proactively. This transforms what would be a problematic reverse flow condition into a controlled operational state, maintaining power generation continuity while preventing reverse flow.
3Extent of automation
If reverse flow control is implemented with control period and communication method, then basic control is achieved, but control delay causes instantaneous reverse flow
Solution Approach 1:
The control device performs calculations and issues control commands in advance of when reverse flow conditions would occur, compensating for the inherent control period and communication delays. By acting preliminarily, the system ensures that control actions are already in effect by the time the actual power flow conditions materialize, eliminating the adverse effects of control delay.
Solution Approach 2:
The control device dynamically adjusts control commands based on real-time conditions, predicted renewable energy output, and forecasted load variations. This dynamic control approach allows the system to adapt to changing conditions and maintain accurate reverse flow control despite fixed control periods and communication delays, as commands are continuously updated to reflect current system state.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
According to an embodiment, a reverse flow power control device (100) includes: an input unit (110) that accepts actual values of output power of the power conditioner (20), load power with respect to the load device (30), and reception power, and a minimum reception power value; a storage unit (130); and a calculator (120) having an output controller (121p) that calculates an output command calculation value, a load controller (121h) that calculates a load command calculation value, and a command value recalculator (122) that calculates, by using the respective actual values, the output command calculation value, the load command calculation value, and the minimum reception power value, an output command value with respect to the power conditioner (20), in order to prevent a reception power value from the power system from becoming less than the minimum reception power value.