A control circuit for a power factor correction (PFC) circuit, the control circuit includes a multiplier having first, second, and third multiplier inputs and a multiplier output. The control circuit has an adder having first and second inputs and an output. The first input of the adder is coupled to the multiplier output. The control circuit further includes a root mean square (RMS) calculation circuit configured to determine a square of a root mean square of an input sinusoidal voltage. The RMS calculation circuit has an output coupled to the second multiplier input. An input voltage square calculation circuit is configured to determine a square of the input sinusoidal voltage. The input voltage square calculation circuit has an output coupled to the third multiplier input.

A control circuit for a power factor correction (PFC) circuit, the control circuit includes a multiplier having first, second, and third multiplier inputs and a multiplier output. The control circuit has an adder having first and second inputs and an output. The first input of the adder is coupled to the multiplier output. The control circuit further includes a root mean square (RMS) calculation circuit configured to determine a square of a root mean square of an input sinusoidal voltage. The RMS calculation circuit has an output coupled to the second multiplier input. An input voltage square calculation circuit is configured to determine a square of the input sinusoidal voltage. The input voltage square calculation circuit has an output coupled to the third multiplier input.

A control circuit for a power factor correction (PFC) circuit, the control circuit includes a multiplier having first, second, and third multiplier inputs and a multiplier output. The control circuit has an adder having first and second inputs and an output. The first input of the adder is coupled to the multiplier output. The control circuit further includes a root mean square (RMS) calculation circuit configured to determine a square of a root mean square of an input sinusoidal voltage. The RMS calculation circuit has an output coupled to the second multiplier input. An input voltage square calculation circuit is configured to determine a square of the input sinusoidal voltage. The input voltage square calculation circuit has an output coupled to the third multiplier input.

Disclosed are an online analysis system and method for a line loss of a transmission line. The system includes: a terminal extension and a terminal host, where time information synchronization between the terminal extension and the terminal host and between terminal extensions is performed by a clock synchronization module, and communication between the terminal extension and the terminal host and between the terminal extensions is performed by a communications module; and a line loss management platform, configured to receive measurement data of the terminal extension and the terminal host, match time information in the measurement data, and if time information in the measurement data of the terminal extension and the terminal host is matched, and time information in measurement data of the terminal extensions is matched, determine corresponding line loss information based on corresponding measurement information.

Disclosed are an online analysis system and method for a line loss of a transmission line. The system includes: a terminal extension and a terminal host, where time information synchronization between the terminal extension and the terminal host and between terminal extensions is performed by a clock synchronization module, and communication between the terminal extension and the terminal host and between the terminal extensions is performed by a communications module; and a line loss management platform, configured to receive measurement data of the terminal extension and the terminal host, match time information in the measurement data, and if time information in the measurement data of the terminal extension and the terminal host is matched, and time information in measurement data of the terminal extensions is matched, determine corresponding line loss information based on corresponding measurement information.

A diagnosis device for diagnosing a diagnosis target machine having a rotary machine on the basis of a measured current during rotation of the rotary machine is provided with: an effective value acquisition unit configured to acquire an effective value of the measured current for each specified number of cycles in a target current waveform which is time transition of the measured current in a first predetermined period; a distribution information calculation unit configured to calculate a target distribution information which represents a distribution state of a plurality of the effective values acquired; and a detection unit configured to perform abnormality detection of the diagnosis target machine on the basis of the calculated target distribution information.

A diagnosis device for diagnosing a diagnosis target machine having a rotary machine on the basis of a measured current during rotation of the rotary machine is provided with: an effective value acquisition unit configured to acquire an effective value of the measured current for each specified number of cycles in a target current waveform which is time transition of the measured current in a first predetermined period; a distribution information calculation unit configured to calculate a target distribution information which represents a distribution state of a plurality of the effective values acquired; and a detection unit configured to perform abnormality detection of the diagnosis target machine on the basis of the calculated target distribution information.

Provided an apparatus that receives time series data from a data storage unit storing time series of sample data or feature values calculated from the sample data, computes a measure indicating change and repetition characteristics of the time series data, based on sample value distribution thereof, selects a state model structure to be used for model learning and estimation, from state models including a fully connected state model and a one way direction state model, based on the measure and stores the selected state model in a model storage unit.

Provided an apparatus that receives time series data from a data storage unit storing time series of sample data or feature values calculated from the sample data, computes a measure indicating change and repetition characteristics of the time series data, based on sample value distribution thereof, selects a state model structure to be used for model learning and estimation, from state models including a fully connected state model and a one way direction state model, based on the measure and stores the selected state model in a model storage unit.

Examples of operating an Intelligent Electronic Device (IED) during power swings, are described. In an example, voltage measurements for a phase is received and sampled. Root mean square (RMS) values of the voltage samples is calculated based on the voltage measurements. Delta quantities for each phase are calculated based on the RMS values. Each of the RMS values and delta quantities are associated with respective sampling instants. In response to a delta quantity being greater than a predefined threshold, a peak delta quantity is detected. A time interval between a sampling instant associated with the peak delta quantity and a sampling instant associated with a first delta quantity is determined. Based on a comparison of the time interval with a threshold time, a disturbance condition may be detected as a power swing and consequently, fault detection at the IED may be blocked.