Capacitor Bank Voltage Control for Distribution Feeders
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Power distribution systems face challenges in maintaining optimal voltage levels along distribution feeders, leading to increased energy costs and equipment wear due to voltage fluctuations and reactive power management, particularly when communication losses occur with capacitor banks reverting to local operating modes.
Innovation Solution
A method and system that utilize a plurality of capacitor banks with adjustable operational set points, controlled by a computing device and voltage sensors, to connect or disconnect from the distribution feeder based on predetermined threshold values, thereby flattening the voltage profile and reducing reactive power, even in the absence of communication with the remote control apparatus.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If capacitor banks operate in local mode with predefined criteria, then automatic voltage control is maintained, but voltage fluctuations occur when reverting from remote mode
Solution Approach 1:
The patent implements a feedback mechanism where the capacitor bank controller continuously monitors voltage levels and automatically adjusts capacitor bank operation (connect/disconnect) based on voltage thresholds. This closed-loop control ensures voltage stability regardless of communication status, resolving the contradiction between maintaining automatic control and preventing voltage fluctuations during mode transitions.
Solution Approach 2:
The capacitor bank controller operates autonomously using locally stored voltage thresholds and operational criteria. When communication with the remote control apparatus is lost, the system continues to self-regulate voltage without external intervention, eliminating voltage instability caused by mode reversion while maintaining reliable automatic control.
2Reliability
If voltage is transmitted at 126V to ensure minimum 114V at end consumers, then voltage requirements are met, but energy costs increase and equipment lifespan decreases
Solution Approach 1:
The patent dynamically adjusts voltage levels along the distribution feeder by controlling capacitor bank operation based on real-time voltage measurements. Instead of maintaining a fixed high voltage (126V) throughout, the system optimizes voltage locally at different feeder locations, ensuring minimum requirements are met while reducing excessive voltage elsewhere, thereby lowering energy losses and extending equipment lifespan.
Solution Approach 2:
The system applies different voltage control strategies to different locations along the distribution feeder. Capacitor banks are controlled based on local voltage conditions, allowing each section to operate at optimal voltage levels rather than uniformly high voltage, thus meeting compliance requirements while minimizing overall energy loss.
3Power
If reactive power is managed using fixed and switched capacitor banks, then VAr management is achieved, but voltage profile changes occur
Solution Approach 1:
The system uses feedback control where voltage measurements continuously inform capacitor bank operation decisions. By monitoring voltage levels and adjusting capacitor bank status accordingly, the system achieves reactive power management while maintaining stable voltage profile, preventing the voltage fluctuations that would otherwise result from reactive power compensation.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach effectively manages voltage and reactive power, reducing voltage fluctuations and energy costs while minimizing the impact of communication losses, ensuring that consumers receive a stable voltage within the required range and extending the lifespan of electrical equipment.
Implementation Method 1
measuring the first voltage with a voltage sensor associated with the first capacitor bank
Implementation Method 2
Energy storage in the loads results in a time difference between the current and voltage waveforms. During each cycle of the AC voltage, extra energy, in addition to any energy consumed by the load, is temporarily stored in the load in electric or magnetic fields
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
A system (100) for controlling voltage on a distribution feeder (106) includes a plurality of capacitor banks (102a-102n) that can be connected to or disconnected from the distribution feeder. A first bank is configured to connect to the distribution feeder when a first voltage is below a first lower threshold value and to connect to the distribution feeder when the first voltage is above a first upper threshold value. The first upper threshold and first lower threshold are determined based off an operational set point. The system further includes a sensor (109) configured to measure the first voltage and a controller (108) in operable communication with the plurality of capacitor banks configured to determine the operational state of the first and second capacitor banks and, based on the first voltage, send a first instruction to the first capacitor bank, the first instruction causing the capacitor bank to vary the operational set point.