Systems and methods are provided for improving the operation of a computer or other electronic device that utilizes root-mean-square (RMS) measurements, e.g., RMS current measurements, by reducing error in the RMS measurement. A series of measurement samples are received at a processor, which executes a noise-decorrelated RMS algorithm including: calculating a current-squared value for each measurement sample by multiplying the measurement sample by a prior measurement sample in the series (rather by simply squaring each measurement sample as in conventional techniques), summing the current-squared values, and calculating an RMS value based on the summed values. The processor may also execute a frequency-dependent magnitude correction filter to correct for frequency-dependent attenuation associated with the noise-decorrelated RMS algorithm. The calculated RMS value has a reduced error, particularly for lower-end current measurements, which may improve the operation of the computer or electronic device that utilizes the RMS value.

Systems and methods are provided for improving the operation of a computer or other electronic device that utilizes root-mean-square (RMS) measurements, e.g., RMS current measurements, by reducing error in the RMS measurement. A series of measurement samples are received at a processor, which executes a noise-decorrelated RMS algorithm including: calculating a current-squared value for each measurement sample by multiplying the measurement sample by a prior measurement sample in the series (rather by simply squaring each measurement sample as in conventional techniques), summing the current-squared values, and calculating an RMS value based on the summed values. The processor may also execute a frequency-dependent magnitude correction filter to correct for frequency-dependent attenuation associated with the noise-decorrelated RMS algorithm. The calculated RMS value has a reduced error, particularly for lower-end current measurements, which may improve the operation of the computer or electronic device that utilizes the RMS value.

According to various aspects and embodiments, a power distribution unit (PDU) is provided. The power distribution unit includes an input configured to receive input power, a plurality of outputs each coupled to the input and configured to receive input power, and each output of the plurality of outputs having an output configured to provide output power, and a controller coupled to the plurality of outputs and configured to determine a plurality of time intervals based on a frequency of the input power, measure a current at each time interval of the plurality of time intervals for each output of the plurality of outputs, generate a plurality of current measurement sums based on current measurement values associated with each time interval of the plurality of time intervals, and determine a root-mean-square (RMS) value based on the plurality of current measurement sums.

According to various aspects and embodiments, a power distribution unit (PDU) is provided. The power distribution unit includes an input configured to receive input power, a plurality of outputs each coupled to the input and configured to receive input power, and each output of the plurality of outputs having an output configured to provide output power, and a controller coupled to the plurality of outputs and configured to determine a plurality of time intervals based on a frequency of the input power, measure a current at each time interval of the plurality of time intervals for each output of the plurality of outputs, generate a plurality of current measurement sums based on current measurement values associated with each time interval of the plurality of time intervals, and determine a root-mean-square (RMS) value based on the plurality of current measurement sums.

A system and method is disclosed for detecting a specific voltage phase, from a multiphase voltage source, and a specific outlet of an intelligent power strip, that is associated with a residual current flow. The method accomplishes this by using a system that employs a statistical time series analysis using a Pearson's correlation coefficient calculation to measure the linear dependence between the discretely sampled residual current waveform and each phase and outlet's discretely sampled current waveforms, in turn. A residual current as low as 1 mA can be accurately measured and its associated voltage phase source, as well as which outlet of an intelligent power strip it flows out of, can be reliably determined.

A system and method is disclosed for detecting a specific voltage phase, from a multiphase voltage source, and a specific outlet of an intelligent power strip, that is associated with a residual current flow. The method accomplishes this by using a system that employs a statistical time series analysis using a Pearson's correlation coefficient calculation to measure the linear dependence between the discretely sampled residual current waveform and each phase and outlet's discretely sampled current waveforms, in turn. A residual current as low as 1 mA can be accurately measured and its associated voltage phase source, as well as which outlet of an intelligent power strip it flows out of, can be reliably determined.

A circuit for power transmission through a single conductive element. The circuit includes an oscillator, a single conductive element, and a load. The oscillator is configured to generate a periodic voltage. The single conductive element is connected in series with the oscillator. The load is connected in series with the single conductive element. The load includes a first diode, a first resistor, and a first inductor. The first diode is connected in series with the single conductive element. The first resistor is connected in series with the first diode. The first inductor is connected between the first diode and the single conductive element. The first inductor is connected in series with the first resistor.

A circuit for power transmission through a single conductive element. The circuit includes an oscillator, a single conductive element, and a load. The oscillator is configured to generate a periodic voltage. The single conductive element is connected in series with the oscillator. The load is connected in series with the single conductive element. The load includes a first diode, a first resistor, and a first inductor. The first diode is connected in series with the single conductive element. The first resistor is connected in series with the first diode. The first inductor is connected between the first diode and the single conductive element. The first inductor is connected in series with the first resistor.

A method for detecting earth-fault conditions in a power conversion apparatus including the following steps: acquiring a first detection signal indicative of an earth-leakage current flowing between the power conversion apparatus and the ground; processing the first detection signal to calculate a first processing signal indicative of a time variant component of the earth-leakage current for one or more selected frequency bands of interest; processing the first detection signal to calculate a second processing signal indicative of a time-invariant component of the earth-leakage current; processing the first and second processing signals to calculate a third processing signal indicative of a resistive component of the earth-leakage current; and processing the third processing signal to determine whether earth-fault conditions are present.

A method for detecting earth-fault conditions in a power conversion apparatus including the following steps: acquiring a first detection signal indicative of an earth-leakage current flowing between the power conversion apparatus and the ground; processing the first detection signal to calculate a first processing signal indicative of a time variant component of the earth-leakage current for one or more selected frequency bands of interest; processing the first detection signal to calculate a second processing signal indicative of a time-invariant component of the earth-leakage current; processing the first and second processing signals to calculate a third processing signal indicative of a resistive component of the earth-leakage current; and processing the third processing signal to determine whether earth-fault conditions are present.