A method for arc detection in a system including a photovoltaic panel and a load connectible to the photovoltaic panel with a DC power line. The method measures power delivered to the load thereby producing a first measurement result of the power delivered to the load. Power produced by the photovoltaic panel is also measured, thereby producing a second measurement result of power produced by the photovoltaic panel. The first measurement result is compared with the second measurement result thereby producing a differential power measurement result. Upon the differential power measurement result being more than a threshold value, an alarm condition may also be set. The second measurement result may be modulated and transmitted over the DC power line.

Method and system allowing more accurate detection and identification of unwanted arcing include novel processing of signal voltage representing recovered power-line current. In one implementation, arc-faults are detected based on numerical analysis where individual cycles of line voltage and current are observed and data collected during each cycle is processed to estimate likelihood of presence of arc-event within each individual cycle based on pre-defined number of arc-events occurring within pre-defined number of contiguous cycles. In another implementation, fast transient current spikes detection can be done by: computing difference values between consecutive line-current samples collected over a cycle, average of differences, and peak-to-peak value of line-current; comparing each difference value to average of difference; comparing each difference value to peak-to-peak value; and, based on calculation of composite of two comparisons, using thresholds to determine if arcing is present within processed cycle.

A method for estimating insulation resistance between a terminal of a battery and an electrical ground, including: connecting a measuring circuit to one terminal of the battery, the measuring circuit including a resistance of known value and a capacitance; application of a known input signal having an input voltage; measurement of an output voltage between the ground and a point located between the resistance of known value and the capacitance; determination of a complex impedance of a dipole of the capacitance and the insulation resistance or determination of parameters of a differential equation; and determination of the insulation resistance from the parameters of the differential equation or the complex impedance.

A system is provided for testing the electrical integrity of an implanted pacemaker or defibrillator lead. The system includes a container holding an electrically conductive solution, such as a saline solution. A voltage source and two electrodes are provided to pass an electrical current through the solution. To use the system, the proximal end of the electrical lead is disconnected from the implanted electronic device, passed through the saline solution and then electrically connected to a device/monitor. During testing, the device/monitor sends a test pulse through the lead and monitors electrical activity in the lead. To test sequential locations along the length of the proximal segment, the segment is drawn through the saline solution and between the electrodes while test pulses are sent and monitored. The monitor detects abnormal electrical activity in the lead indicative of a break in lead insulation.

A method for preventing damage in a bearing of a generator of an electrical power system having a power conversion assembly with a first converter coupled to a second converter, and the power conversion assembly electrically coupled to the generator. Further, the method includes monitoring a phase current and voltage of the first converter. The method also includes calculating a common mode power using the phase current and the voltage of the first converter. Moreover, the method includes comparing the common mode power to a predefined power threshold. The method also includes determining whether the common mode power is indicative of degradation in at least one of a bearing insulation or a ground brush based on the comparison of the common mode power to the predefined power threshold.

Systems, apparatuses, and methods are described for detecting and preventing arcs in a photovoltaic (PV) power system.

A method for arc detection in a system including a photovoltaic panel and a load connectible to the photovoltaic panel with a DC power line. The method measures power delivered to the load thereby producing a first measurement result of the power delivered to the load. Power produced by the photovoltaic panel is also measured, thereby producing a second measurement result of power produced by the photovoltaic panel. The first measurement result is compared with the second measurement result thereby producing a differential power measurement result. Upon the differential power measurement result being more than a threshold value, an alarm condition may also be set. The second measurement result may be modulated and transmitted over the DC power line.

A spark detecting apparatus for devices using electric sliding contact includes a static part, a sliding part becoming electrically conductive while making sliding contact with the static part, a frequency filter selectively passing a voltage signal in a particular band, a volt meter electrically connected to the static part through the frequency filter, and a detecting apparatus for sliding condition determining the presence or absence of spark at the sliding interface between the static part and the sliding part. When a voltage signal detected by the volt meter exceeds a predetermined threshold value, it is determined that a spark has occurred.

A partial discharge acquisition system includes: a synchronization signal sensor device including a sensor module structured to remotely detect a first synchronization electromagnetic signal generated by an alternate current electrical voltage associated with the operation of an electrical object and provide a corresponding first detected electrical signal; a transmitting device structured to irradiate a second synchronization electromagnetic signal related with the first detected electrical signal; a partial discharge detection apparatus including: a receiving device structured to receive the second synchronization electromagnetic signal and generate a corresponding received electrical signal representing at least a timing parameter of the alternate current electrical voltage, the receiving device and the transmitting device being configured to establish a wireless communication link defining a deterministic transmission delay.

A system for testing an insulative material for a spark plug comprises a test spark plug having at least a center electrode and an insulator comprised of an insulative material surrounding at least a portion of the center electrode, wherein the insulator has an end that is closed, whereby the closed end of the insulator encloses an end of the center electrode. The system may further include a test engine that simulates engine conditions, wherein a conventional spark plug is installed in a first ignition port of the test engine and the test spark plug is installed in a second ignition portion of the test engine and a control system for controlling ignition signals to the test spark plug and the conventional spark plug.