Static Transfer Switch Control for Volt-Second Balanced Switchover
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional static transfer switch systems require a large number of components for volt-second balancing, leading to increased cost and complexity, and cause long interruptions in power supply during switchover due to transient AC voltages, potentially triggering undesired resets or shut-downs.
Innovation Solution
Implementing maximum transient voltage (MTV) control and simplified volt-second balancing (SVSB) to reduce hardware and firmware requirements by a third while minimizing power interruptions, by disconnecting initial voltages, determining qualified alternate voltages that won't saturate the load during the wait time, and applying them before achieving full volt-second balance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional VSB control is used to avoid transformer saturation, then transformer saturation is prevented, but power interruption time increases
Solution Approach 1:
The patent applies preliminary action by pre-calculating and storing volt-second balance information before the actual transfer occurs. The system integrates voltages and calculates volt-second values in advance, so that when a transfer is needed, the pre-computed data can be immediately used to determine the optimal transfer moment, minimizing interruption time while ensuring saturation prevention.
Solution Approach 2:
The patent implements feedback by continuously monitoring the volt-second balance between normal and alternate voltages. The system uses integrators to accumulate voltage information over time and compares the accumulated values to determine when volt-second balance has been achieved, providing real-time feedback for optimal transfer timing that prevents transformer saturation while minimizing power interruption.
2Measurement precision
If multiple voltage sensors and integrators are used for VSB, then volt-second balancing accuracy is improved, but device complexity increases
Solution Approach 1:
The patent applies merging by combining the voltage sensing and integration functions into a single integrated circuit or processor-based system. Instead of using separate physical sensors and integrators for each phase, the system uses shared computational resources to perform voltage measurement and integration, reducing the number of discrete components while maintaining measurement precision through software-based calculation.
Solution Approach 2:
The patent replaces physical hardware integrators with software-based integration algorithms running on a processor. The system uses digital signal processing to accumulate voltage values over time and calculate volt-second values, substituting mechanical/electronic integration circuits with computational methods that achieve the same function with fewer physical components.
Data Source
AI summary
A power system performs a method comprising: applying normal voltages to a load as load voltages; upon detecting a power fault that necessitates applying alternate voltages to the load in place of the normal voltages, disconnecting the normal voltages from the load; while waiting to detect a volt-second balance between the alternate voltages and the load voltages, determining one or more qualified voltages of the alternate voltages that will not saturate the load, and applying the one or more qualified voltages to the load as the load voltages; upon detecting the volt-second balance, additionally applying to the load each alternate voltage that is not the one or more qualified voltages; and after additionally applying, volt-second balancing the alternate voltages with the load voltages.