An exemplary power conversion system includes a power conversion device and a control system. The power conversion device converts electrical power from one form to another. The power conversion device includes at least one switching element capable of being turned off to block an electrical current flowing through the at least one switching element. The control system is electrically coupled to the power conversion device for monitoring an electrical current flowing through the at least one switching element and for monitoring at least one parameter in association with the operation of the power conversion system. The control system further generates an over-current threshold value that is variable with respect to at least one monitored parameter.

A power management circuit has a power input terminal coupled to a power supply or a load, a power terminal configured to provide an output voltage, and a battery terminal coupled to a battery. The power management circuit further has a current limiting circuit, an over-current indication circuit and an over-current threshold selecting circuit. The current limiting circuit compares a current feedback signal indicative of an output current flowing out of the power terminal with a current threshold signal and generates a square wave signal. The over-current indication circuit generates an over-current indication signal based on the square wave signal. The over-current threshold selecting circuit selects a first over-current threshold voltage or a second over-current threshold voltage as an over-current threshold voltage based on the over-current indication signal, wherein the first over-current threshold voltage is higher than the second over-current threshold voltage.

A method of establishing current limits for each of a plurality of device couplers mounted on a trunk of an electrical circuit at distributed physical positions, in which each of said device couplers is capable of servicing one or more spurs connected thereto, and in which said trunk has a total trunk current and a known resistive component, comprising the steps of: a) establishing physical characteristics of the electrical circuit including i) an order in which said device couplers are mounted on said trunk along its length; ii) a load current each device coupler requires to service the one or more spurs connected thereto; and, iii) a voltage drop of each of said sections of trunk caused by the resistive component thereof, which is proportional to a physical length thereof and the combined load currents of each device coupler serviced by that section of trunk; b) calculating a current limit for each device coupler, which current limit is greater than said load current, according to a predetermined tolerance rationale; c) calculating an intermediate trunk current available to each device coupler by deducting from said total trunk current the current limits of each device coupler preceding that device coupler in said order, as well as a consequential reduction in current caused by said voltage drop of each of said sections of trunk preceding that device coupler; and, d) adjusting said current limits so none exceeds the intermediate trunk current available to the corresponding device coupler.

An overload control device for use with a floor machine having an electric motor is disclosed. The overload control device can include a power input and a power output connectable to the electric motor. The device can include a load detector, a current sensor operative to sense a current value supplied to the motor via the power output, and a cutoff relay interconnecting the power input and the power output. The cutoff relay being operative to supply power from the power input to the power output when activated, and interrupt power when deactivated. A controller receives a load present indication from the load detector and activates the cutoff relay if a load is present. The controller receives a current value from the current sensor, determines if the current value is greater than a threshold value, and deactivates the cutoff relay when the current value is greater than the threshold value.

A protective arrangement includes an input configured to receive an input current from a current supply; one or more outputs configured to connect to one or more connection lines to supply current to one or more electric loads; one or more current supply paths arranged between the input and the one or more outputs; a first path circuit breaker and a second path circuit breaker in a series connection in a current supply path of the one or more current supply paths and configured to interrupt a current flow in the current supply path; and one or more setting units configured to set a trip current for at least one of the first path circuit breaker or the second path circuit breaker.

The method for controlling selectivity of electric equipment comprises: communication of electric equipment settings between at least one electric equipment unit and a data processing device, computation of the selectivity of electric equipment according to said electric equipment settings, storing and communication of data representative of the selectivity settings and data, supervision of changes of settings and/or of changes of equipment, and checking of the compatibility between new settings after a change and the selectivity computation. The device and installation comprise means for implementing the selectivity control method.

An electrical apparatus of an electrical power distribution network may be controlled by accessing, at a control system, one or more operating parameters, the operating parameters being associated with the operation and control of the electrical apparatus; adjusting one or more of the accessed operating parameters, the adjustment being based on data associated with the electrical apparatus; and generating a control signal for the electrical apparatus based on at least one adjusted parameter, the control signal being sufficient to control the electrical apparatus in accordance with the adjusted operating parameter, where controlling the electrical apparatus includes causing contacts of the electrical apparatus to disconnect from each other to prevent electrical current from flowing through the electrical apparatus and causing the contacts of the electrical apparatus to connect to each other to allow current to flow through the electrical apparatus.

A power delivery system includes a programmable current limit switch circuit connected between a power supply and electronic control circuits that are susceptible to single event latch-up. The programmable current limit switch is connected in a power bus between the power supply and the electronic control circuits. The programmable current limit switch circuit removes power from the electronic control circuits when an over-current condition persists for a blank time period, and restores power to the electronic control circuits after a retry time period.

Real-time detection of high-impedance faults in a distribution circuit is described. The real-time detection of high-impedance faults includes two steps. First, adaptive soft denoising is employed to perform a filtering process on a healthy dataset, and to determine a threshold. This reduces the rate of false alarms. Second, faulty datasets are prefiltered via adaptive soft denoising, then the denoised signals are processed via discrete wavelet transform to perform high-impedance fault detection using the threshold.

A distribution manager for a power microgrid system includes a main bus, and a circuit breaker coupled to the main bus and to one of a load and an inter-microgrid connection system of the power microgrid system, the circuit breaker being structured to operate based on a set of functional trip settings. The distribution manager is structured and configured to: (i) determine an available source overcurrent that will be fed through the circuit breaker, (ii) determine a number of trip parameter settings based on at least the available source overcurrent, and (iii) set the functional trip settings of the circuit breaker based on the determined number of trip parameter settings.