Power supply system with automatic transfer switches

Abstract

A power supply system for automatic transfer switch applications comprises two first switch apparatuses, two second switch apparatuses, and a control unit. Each first switch apparatus comprises a first relay switch and a first switch assembly. The first switch assembly comprises a first bypass switch, a first semi-controllable switch, and a first fully-controllable switch. Each second switch apparatus comprises a second relay switch and a second switch assembly. The second switch assembly comprises a second bypass switch, a second semi-controllable switch, and a second fully-controllable switch. The control unit controls the two first switch apparatuses and the two switch apparatuses to uninterruptedly supply power to a load.

Description

BACKGROUNDTechnical Field[0001]The present disclosure relates to a power supply system, and more particularly to a power supply system with automatic transfer switches.Description of Related Art[0002]Automatic transfer switch (ATS) is a power circuit switch, which is used to switch power supply circuits between a main power source and a backup power source so as to uninterruptedly supply power to a load. When the main power source is insufficient, interrupted or abnormal, the automatic transfer switch will automatically switch the power supply circuit to the backup power source, so that the backup power source can alternatively continue to provide stable power to the load, which ensures the equipment of the load being able to continue to operate and avoid further risks of property or human damage and financial losses caused by the power failure condition.[0003]Please refer to FIG. 1. The power supply system has a dual power source circuit structure, and the two power sources V1 and ...

AI Technical Summary

Benefits of technology

[0014]More specifically, the power supply system with automatic transfer switches and the method of controlling the same are provided to use fully-controllable semiconductor switches such as IGBTs or MOSFETs that have the ability to be turned off when large currents flow through, further having shorter switching time and being on / off controllable to achieve more accurate switching control, thereby increasing power supply quality and reliability.

Problems solved by technology

However, during the process of switching the power sources, some issues may occur due to the mechanical characteristics of the relay, such as slow switching time and unable to withstand instantaneous large currents (poor reliability at high currents).

Furthermore, after switching for many times, the relay switches may fail to open or close, which may cause switching failures or mismatches of switching sequence between the main power source V1 and the backup power source V2.

However, such technology of automatic transfer switches is not only limited to the application of voltage interruption, but also can be applied to any abnormality or failure of the main power source, such as voltage sags or surges.

However, in the process of disconnecting the power source of the circuit in FIG. 2, due to the characteristic of the SCR that it cannot be turned off by external control signals, the circuit still needs to be cut off by the relay switches.

Therefore, the switching issues may still occur because of the above-mentioned characteristics of the relay switches, such as slow switching time and poor reliability at large currents.

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