Patent Application
20230112526
The field of the invention generally pertains to detection of abnormal electrical conditions.
This disclosure is directed to systems and methods for simply, quickly and accurately detecting the presence of abnormal operating conditions in an electrical power distribution system and what they are caused by. Such abnormal operating conditions may be due to interconnection problems that can occur either between or within the components of a power distribution system. For example, wiring connections may develop high resistances, arcing may occur in the wiring or within the components, etc. Such abnormal operating conditions caused by, e.g., the foregoing interconnection problems, can result in faults and excessive power loss in the system if they are not promptly located and corrected. In accordance with this disclosure, by appropriately monitoring and comparing voltages and currents within the system, such faults may be readily detected so that corrective steps may be taken to avoid damage to the system.
In particular, this disclosure allows for the quick and accurate detection of faulty operating conditions and bad interconnections between and within components of an electrical power distribution system. By way of example, this disclosure allows for detection of arcing in the wiring and components, high resistance connections, and other causes of excessive power loss in a power system. In accordance with this disclosure, simple rules may be used to compare the voltage at each end of a conductor, or on each side of a system component, and/or the current through it, and will declare a fault when the power level exceeds what is expected.
By comparing voltages between system components, and/or from input to output of such components, the methods disclosed herein are simple to implement, work with AC or DC power sources, and at any voltage or current level.
This disclosure is made in conjunction with the accompanying Figures, in which:
Faulty connections in power interconnect wiring and within loads connected to a power distribution system can lead to high resistance, arcing, and unacceptable power losses. In critical applications, such as aircraft power systems where safety concerns are paramount, such faulty connections, if not detected and promptly corrected, can pose significant operational and safety issues.
An illustration of a faulty connection between a voltage source and a load is shown in
The current consumed in a load indicates a great deal about the health of that load. Too much current or too little current are both events that indicate something is wrong. By way of example, and in accordance with this disclosure, circuit breaker trip events may be analyzed to identify the likely failure mode that has caused the trip to occur. For example, an instantaneous circuit breaker trip event typically occurs when a current spike is generated that exceeds 10 times the breaker's rating. This type of event, which indicates that a very high current was interrupted, is most likely caused by a wiring fault. On the other hand, a circuit breaker over-current trip event occurs when current causes the breaker to trip after an extended period of over-current. When such over-current trip event occurs, it is most likely indicative of a fault within the load, rather than a wiring fault.
As shown in
In accordance with this disclosure, the voltage and current data can be collected and analyzed by a computational device. The computation device may oftentimes already be present in the system and used for other purposes, or it may be readily added, if need be, by workers of ordinary skill in the art.
In accordance with this disclosure, to aid in identifying abnormal operating conditions, such data is analyzed in real time using a set of simple rules that may be implemented in software. The rules are designed to promptly identify and locate power losses that should not exist when the system is working correctly.
By way of example, actual current usage may be compared to pre-set maximum and minimum current levels. Such maximum and minimum currents can also be adjusted based on prior stored data (compare with average), or can vary based on operational profiles. As another example, a rule for finding high resistance wire connections or series arc faults may be to set to identify a delta voltage limit between the output of one device and the input of another. Such voltage limit could be absolute, e.g., based on regulatory requirements for wire voltage drop (e.g., max 2% drop in voltage), or set by the expected wire resistance and the measured current.
As yet another example, a rule may be defined to find a faulty device in the power supply system by setting and monitoring current limits for the minimum and maximum current draw of a component when it is powered, Such current limits may be either absolute limits or based on current flow averaged over time.
Another exemplary rule may be used to find the likely failure mode that causes an electronic protection device to trip. In this case, such rule may differentiate between an over-current trip event (current causing the breaker to trip after an extended period of over-current) and an instantaneous trip event (e.g., caused by a current spike exceeding 10 times the breaker's rating). Overcurrent trips would likely indicate a device fault, whereas an instant trip would be likely be indicative of a wiring fault.
An alternative voltage or current measurement method that may be used when voltage and current data is not available on a data bus is shown in
The present disclosure claims the benefit of priority of U.S. Provisional Patent Application No. 63/243,138, filed Sep. 11, 2021, which is herein incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63243138 | Sep 2021 | US |
