PowerSystem

Module for creating power system objects.

This module provides classes and methods to define power systems, including phases, zero-crossing detection, and calculation of electrical quantities like voltage, current, and power.

Classes:

Name	Description
PowerSystem	Represents the overall power system, allowing configuration, data processing, and analysis.
PowerPhase	Represents a single phase of the power system.

Imports

• numpy: For numerical calculations.
• List: For type hinting lists.
• logging: For logging messages.
• AcqBuffer, DataChannelBuffer: From daqopen.channelbuffer for data handling.
• ZeroCrossDetector: From pqopen.zcd for detecting zero crossings in signals.

PowerPhase

Bases: object

Represents a single phase in the power system.

Attributes:

Name	Type	Description
_u_channel	AcqBuffer	Voltage channel buffer for the phase.
_i_channel	AcqBuffer	Current channel buffer for the phase.
_number	int	Identifier number for the phase.
name	str	Name of the phase.
_calc_channels	dict	Dictionary for storing calculated data channels.

__init__(u_channel, i_channel=None, number=1, name='')

Initializes a PowerPhase object.

Parameters:

Name	Type	Description	Default
u_channel	AcqBuffer	Voltage channel buffer.	required
i_channel	AcqBuffer	Current channel buffer. Defaults to None.	None
number	int	Phase number. Defaults to 1.	1
name	str	Name of the phase. Defaults to an empty string.	''

update_calc_channels(features)

Update the calculation channels depending of active features

Parameters:

Name	Type	Description	Default
features	dict	Dict of features	required

PowerSystem

Bases: object

Represents the overall power system, including zero-crossing detection, phase management, and power system calculations.

Attributes:

Name	Type	Description
_zcd_channel	AcqBuffer	Channel buffer for zero-crossing detection data.
_samplerate	float	Sampling rate of the input signal.
_time_channel	AcqBuffer	Optional time channel buffer.
_zcd_cutoff_freq	float	Cutoff frequency for the zero-crossing detector.
_zcd_threshold	float	Threshold for zero-crossing detection.
_zcd_minimum_frequency	float	Minimum frequency for valid zero-crossing detection.
nominal_frequency	float	Nominal frequency of the power system.
nper	Optional[int]	Number of periods for analysis (if applicable).
_phases	List[PowerPhase]	List of phases in the power system.
_features	dict	Configuration for harmonic and fluctuation calculations.
output_channels	dict	Dictionary of output data channels.

__init__(zcd_channel, input_samplerate, zcd_cutoff_freq=50.0, zcd_threshold=1.0, zcd_minimum_freq=10, nominal_frequency=50.0, nper=10)

Initializes a PowerSystem object.

Parameters:

Name	Type	Description	Default
zcd_channel	AcqBuffer	Channel buffer for zero-crossing detection.	required
input_samplerate	float	Sampling rate of the input signal.	required
zcd_cutoff_freq	float	Cutoff frequency for zero-crossing detection. Defaults to 50.0.	50.0
zcd_threshold	float	Threshold for zero-crossing detection. Defaults to 1.0.	1.0
zcd_minimum_freq	float	Minimum frequency for valid zero crossings. Defaults to 10.	10
nominal_frequency	float	Nominal system frequency. Defaults to 50.0.	50.0
nper	int	Number of periods for calculations. Defaults to 10.	10

add_phase(u_channel, i_channel=None, name='')

Adds a phase to the power system.

Parameters:

Name	Type	Description	Default
u_channel	AcqBuffer	Voltage channel buffer.	required
i_channel	AcqBuffer	Current channel buffer. Defaults to None.	None
name	str	Name of the phase. Defaults to an empty string.	''

enable_harmonic_calculation(num_harmonics=50)

Enables harmonic analysis for the power system.

Parameters:

Name	Type	Description	Default
num_harmonics	int	Number of harmonics to calculate. Defaults to 50.	50

enable_mains_signaling_calculation(frequency)

Enables calculation of mains signaling voltage Complies to IEC 61000-4-30

Parameters:

Name	Type	Description	Default
frequency	float	Expected frequency of signaling voltage	required

enable_nper_abs_time_sync(time_channel, interval_sec=600)

Enables synchronisation of multi-period calculation to absolute rounded timestamp. Complies to IEC 61000-4-30 overlapping

Parameters:

Name	Type	Description	Default
time_channel	AcqBuffer	Channel buffer for time information	required
interval_sec	int	Resync interval in seconds	600

enable_under_over_deviation_calculation(u_din)

Enables calculation of under and overdeviation Complies to IEC 61000-4-30

Parameters:

Name	Type	Description	Default
u_din	float	Dimensioned voltage (typ. nominal voltage)	required

get_aggregated_data(start_acq_sidx, stop_acq_sidx)

Retrieves aggregated data for the specified sample range.

Parameters:

Name	Type	Description	Default
start_acq_sidx	int	Start sample index.	required
stop_acq_sidx	int	Stop sample index.	required

Returns:

Name	Type	Description
dict	dict	Aggregated data values.

process()

Processes new data samples, performing zero-crossing detection and calculations for each period.