Distributed Generation System Reactive Power Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electrical power distribution circuits often face issues with substandard power supply due to impedance, reactive power, and harmonic currents, leading to overheating, failures, and inefficiencies, which cannot be fully addressed by simply upgrading components.
Innovation Solution
A distributed generation system that includes a source of stored DC energy, a controller, an inverter, and a converter, which detects line voltage and current to deliver or absorb power, reducing phase shifts, harmonics, and balancing currents in AC power lines, thereby maintaining optimal voltage levels and reducing losses.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the size of components in the distribution circuit is increased to reduce reactive power losses and improve voltage stability, then voltage stability and power delivery capability are improved, but system cost and device complexity increase significantly
Solution Approach 1:
The patent divides the distribution circuit into multiple zones with distributed generation units (DGUs) placed at strategic locations. Each DGU operates semi-autonomously to manage local reactive power and voltage, segmenting the overall system control function. This allows voltage stability to be maintained in each segment without requiring the entire distribution circuit to be upgraded with larger components.
Solution Approach 2:
The patent introduces DGUs as intermediary devices between the utility grid and end-user loads. These DGUs act as local voltage regulators and reactive power compensators, mediating the power flow and voltage levels in the distribution circuit. By placing intelligent controllers at distributed locations, the system achieves voltage stability without requiring universal upgrading of all distribution components.
2Loss of energy
If distributed generation units are deployed to improve voltage stability and reduce reactive power losses, then system efficiency and reliability are improved, but device complexity and initial cost increase
Solution Approach 1:
The DGUs described in the patent are designed to perform multiple functions simultaneously: they generate real power, provide reactive power compensation, regulate voltage, and reduce harmonic distortion. This multi-functionality allows a single distributed generation unit to address multiple power quality issues that would otherwise require separate devices, thereby reducing overall system complexity despite the addition of distributed units.
Solution Approach 2:
The patent utilizes power electronic converters in DGUs to dynamically change electrical parameters (voltage, current, frequency, power factor) to optimize power delivery. By controlling the operating parameters of distributed units, the system can adapt to varying load conditions and compensate for reactive power losses without requiring permanent infrastructure changes or complex mechanical adjustments throughout the distribution circuit.
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
The system effectively mitigates load-induced phase shifts, reduces harmonic currents, and balances currents in AC power lines, improving the efficiency and reliability of power distribution by injecting or withdrawing reactive power and harmonic currents, thus preventing overheating and failures in distribution circuits.
Implementation Method 1
an inverter connected between the power line and the source of stored DC energy and connected to receive the first set of firing signals from the controller
Implementation Method 2
a converter connected between the DC power source and the source of stored DC energy and connected to receive the second set of firing signals from the controller
Implementation Method 3
a controller operative for: detecting line voltage and line current of the AC power line and for providing a first set of firing signals related to the AC line voltage and/or the AC line current
Data Source
AI summary
A distributed generation system is connected to an AC power line that provides AC electrical power from a source to a load. The distributed generation system includes a DC electrical power source, a capacitor for storing DC electrical power, a converter for converting electrical power stored in the DC electrical power source at a first voltage to a second, greater voltage for storage in the capacitor. The system includes an inverter for inverting the electrical power stored in the capacitor at the second voltage into AC electrical power having a peak voltage less than the second voltage. A controller is provided and operative for controlling the operation of the converter and the inverter to deliver electrical power stored in the DC electrical power source to the capacitor for delivery as AC electrical power to the AC power line.