Component List¶
This document outlines the available components in Kestrel EMT.
Note that this page is programmatically generated.
Circuitry¶
Basic Components¶
Resistor¶
Ideal resistor model.
Parameters:
Input - Resistance or Power
Phases - 1-Ø or 3-Ø or 3-Ø Wye or 3-Ø \(\Delta\)
Resistance - Resistance in Ohms
Voltage - Nominal voltage rating in RMS (line to line for 3-Ø, line to neutral for 1-Ø)
Power - Total nominal power rating
Inductor¶
Ideal inductor model.
Parameters:
Phases - 1-Ø or 3-Ø or 3-Ø Wye or 3-Ø \(\Delta\)
Input - Inductance (L) or Reactance (X) or Reactive Power (Q)
Inductance
Reactance - Reactance in Ohms
Frequency
Voltage - Nominal voltage rating in RMS (line to line for 3-Ø, line to neutral for 1-Ø)
Power - Total nominal reactive power rating
Frequency
Capacitor¶
Ideal capacitor model
Parameters:
Phases - 1-Ø or 3-Ø or 3-Ø Wye or 3-Ø \(\Delta\)
Input - Capacitance (C) or Reactance (X) or Reactive Power (Q)
Capacitance
Initial_Voltage
Reactance - Reactance in Ohms
Frequency
Voltage - Nominal voltage rating in RMS (line to line for 3-Ø, line to neutral for 1-Ø)
Power - Total nominal reactive power rating
Frequency
RLC¶
Combined series RLC model.
Parameters:
Phases - 1-Ø or 3-Ø or 3-Ø Wye
Resistance
Inductance
Capacitance
Coupled RL¶
Coupled 3-Ø series RL model.
Parameters:
Input - Inductance (L) or Reactance (X)
R1 - Positive Sequence Resistance
R0 - Zero Sequence Resistance
L0 - Zero Sequence Inductance
L1 - Positive Sequence Inductance
X0 - Zero Sequence Inductive Reactance
X1 - Positive Sequence Inductive Reactance
Frequency
Varistor¶
Nonlinear resistor defined as a piecewise linear function V(i). Characteristic must be monotonically increasing. Negative currents and voltages are not allowed (characteristic is assumed to be symmetric). Do not include the point (0,0). The ArresterWorks Lightning Arrester VI Characteristic is courtesy of Jonathan Woodworth (arresterworks.com).
Parameters:
Phases - 1-Ø or 3-Ø or 3-Ø Wye or 3-Ø \(\Delta\)
Characteristic - Manual VI or ArresterWorks
VI Curve
MCOV
Class - Light Duty or Normal Duty or Heavy Duty or 5 kA or 10 kA or Station or Class 1 or Class 2 or Class 3 or Class 4 or Class 5
Sources¶
Voltage Source¶
Configurable voltage source. The 8/20µs and 1.2/50µs waves are implemented based on IEEE Std C62.45.
Parameters:
Waveform - Cosine or Impulse or 8/20µs Wave or 1.2/50µs Wave or DC
Phases - 1-Ø or 3-Ø or 3-Ø Wye
Scaling - VLN RMS or VLL RMS or VLN Peak or VLL Peak
Sequence - Zero or Positive or Negative
Amplitude - Voltage Amplitude, Line-to-Line RMS
Frequency
Phase
Ton
Resistance
Tstart
Tstop
Tstart
Tstop
Grid Source¶
Configurable 3-Ø source with convenient inputs such as short circuit ratio (SCR). This model is simply a sinusoidal voltage source in series with a series R-L component. NERC PRC-029 voltage ridethrough (VRT) waveforms 1 and 2 correspond to Table 1 (AC-Connected Wind IBR) and Table 2 (All Other IBR) respectively. Playback of the voltage waveform occurs behind the Grid Source impedance, so the voltage at the terminals of the component will differ. The full VRT waveform takes about 15.5 seconds to run.
Parameters:
Playback - Flat Run or PRC-029-1 VRT 1 or PRC-029-1 VRT 2
Start Time
Voltage - Voltage Amplitude
Frequency
Phase
SCR - Short Circuit Ratio
P_project - Facility size. SCR and P_project are used to calculate the short circuit strength
XR Ratio - Inductive Reactance - Resistance Ratio of the grid equivalent
Current Source¶
Configurable current source. The 8/20µs and 1.2/50µs waves are implemented based on IEEE Std C62.45.
Parameters:
Waveform - Cosine or Impulse or DC or 8/20µs Wave or 1.2/50µs Wave
Phases - 1-Ø or 3-Ø or 3-Ø Wye
Scaling - I RMS or I Peak
Sequence - Zero or Positive or Negative
Amplitude - Current Amplitude
Frequency
Phase
Ton
Tstart
Tstop
Tstart
Tstop
Programmable Source¶
Source current/voltage is dependent on the input math blocks.
Parameters:
Phases - 1-Ø or 3-Ø or 3-Ø Wye
Source Type - Voltage or Current
Resistance
Ground¶
Ground reference.
Transformers¶
Ideal Transformer¶
Ideal transformer (Note: Even transforms DC). Three phase transformers with Wye-\(\Delta\) and \(\Delta\)-Wye have standard ANSI phase shift (primary voltage leads by 30 degrees).
Parameters:
Phases - 1-Ø or 3-Ø Wye-Wye or 3-Ø Wye-\(\Delta\) or 3-Ø \(\Delta\)-Wye or 3-Ø \(\Delta\)-\(\Delta\)
n - Winding ratio (n:1)
Tap Changing
Taps - Total number of tap settings.
TapSize - Tap size (per unit).
Transformer¶
Transformer with typical nameplate specified values. Three phase transformers with Wye-\(\Delta\) and \(\Delta\)-Wye have standard ANSI phase shift (primary voltage leads by 30 degrees).
Parameters:
Phases - 1-Ø or 3-Ø Wye-Wye or 3-Ø Wye-\(\Delta\) or 3-Ø \(\Delta\)-Wye or 3-Ø \(\Delta\)-\(\Delta\)
V1 - Primary Voltage
V2 - Secondary Voltage
Xs - Series Reactance
Rs - Series Resistance
Ie - Excitation Current
S - XFMR MVA rating, used for impedance calculation only.
Frequency - System frequency, used for impedance calculation
Taps - Total number of tap settings.
TapSize - Tap size (per unit).
Switching¶
Time Switch¶
Time programmable switch.
Parameters:
Phases - 1-Ø or 3-Ø or 3-Ø Wye
Starts Open - Specify whether the switch is open during the steady state solution.
Pole Control - Individually control the switch poles.
Ron - Series resistance when switch is on (closed).
Roff - Series resistance when switch is on (open).
I Interrupt - Current threshold for switch interrupting current.
Switch Times
Switch Times
Switch Times A
Switch Times B
Switch Times C
Controlled Switch¶
Switch controllable using math blocks. Switch is closed if input is greater than or equal to 1.
Parameters:
Phases - 1-Ø or 3-Ø or 3-Ø Wye
Ron - Series resistance when switch is on (closed).
Roff - Series resistance when switch is on (open).
I Interrupt - Current threshold for switch interrupting current.
Diode¶
Ideal diode (Vd = 0).
Parameters:
Auto Snub - Improves numerical stability by inserting a small RC circuit across the diode, dependent on timestep.
Transmission Lines¶
Transmission Line¶
Transmission line using Bergeron model.
Parameters:
Phases - 1-Ø or 3-Ø or 3-Ø Coupled
Length
Lp - Series inductance per unit length.
Cp - Shunt capacitance per unit length.
Rp - Series resistance per unit length.
L1 - Series positive sequence inductance per unit length.
L0 - Series zero sequence inductance per unit length.
C1 - Shunt positive sequence capacitance per unit length.
C0 - Shunt zero sequence capacitance per unit length.
R1 - Series positive sequence resistance per unit length.
R0 - Series zero sequence resistance per unit length.
Math¶
Basic¶
Arithmetic¶
Sum/Subtract/Multiply/Divide multiple inputs.
Parameters:
Operation - Sum or Multiply or Divide
Phases - 1-Ø or 3-Ø
Input1 - Plus or Minus
Input2 - Plus or Minus
ABS¶
Outputs the absolute value of the input.
GAIN¶
Multiplies the input(s) by a constant
Parameters:
Phases - 1-Ø or 3-Ø
Gain - Value to scale input by.
TRIG¶
Standard trigonometric functions. All operate in radians.
Parameters:
Function - COS or SIN or TAN or ACOS or ASIN or ATAN
Logic¶
AND¶
Digital Logic AND Gate. Outputs 1 if both inputs are greater than or equal to 1.
OR¶
Digital Logic OR Gate. Outputs 1 if either input is greater than or equal to 1.
NOT¶
Digital logic NOT Gate. If the input is greater or equal to one, returns 0. If the input is less than one, returns 1.
Greater Than¶
Greater-Than comparison. Outputs a 1 if the first (top) input is greater than the second input.
Moving Average¶
Moving Average
Parameters:
Time Constant - Time constant
Special Variable¶
Outputs the value of a special variable, such as the current simulation time.
Parameters:
Variable - TIME or DT
Constant¶
Sets the control input to a constant value.
Parameters:
Value - Constant value.
Signal Source¶
Configurable signal source for control circuits.
Parameters:
Waveform - Cosine or Impulse or Square or Arbitrary
Amplitude
Frequency
Frequency
Phase
Ton
Offset - DC Offset of waveform.
Offset - DC Offset of waveform.
Output
Derivative¶
First order derivative
Integral¶
Basic integrator function implemented using trapezoidal integration. You may enable Min/Max limits, Freeze, or Reset options. The Reset input can be configured to trigger on a rising edge or full level shift.
Parameters:
K - Integrator Gain
Enable Reset - No or On Rising Edge or Yes
Reset Value - Value to reset to, if enabled.
Enable Freeze - Add a freeze input, which freezes the integrator when the input is set to 1.
Max Limit - Maximum limit. Values above or equal to 1e100 disable the limit.
Min Limit - Minimum limit. Values below or equal to -1e100 disable the limit.
Real Pole¶
Real pole function implmented using trapezoidal integration
Parameters:
K - Gain term
T - Time constant
Limiter¶
If the input value is within the Min Limit and Max Limit, it will be output unchanged. Otherwise, it will be limited to the corresponding limit.
Parameters:
Max Limit - Maximum limit. Values above or equal to 1e100 disable the limit.
Min Limit - Minimum limit. Values below or equal to -1e100 disable the limit.
RMS¶
Calculates the root-mean-square equivalent using either a sliding RMS window or a Clarke transform. Use the 3-Ø Clarke option if you need a single phase representation of a 3 phase signal.
Parameters:
Phases - 1-Ø RMS or 3-Ø RMS or 3-Ø Clarke
Frequency - Defines the sliding window size [n= 1/(dt*Frequency)]
nPerCycle - Samples per Cycle. Effective sample frequency is Frequency * nPerCycle.
Line to Line - If checked, the line to line signal will be measured, otherwise, the line to neutral signal will be measured.
Phasor¶
Uses a DFT based algorithm to calculate a phasor. Values are reported as a real/imaginary pair if “Polar” is not checked, otherwise amplitude and phase (radians) is reported.
Parameters:
Phases - 1-Ø or 3-Ø
Frequency - Defines the window size
nPerCycle - Samples per Cycle. Effective sample frequency is Frequency * nPerCycle.
Polar - If checked, reports values in polar coordinates. Otherwise, cartesian values are reported.
Arg¶
Converts a Real/Imaginary pair to Amplitude and Phase.
Parameters:
Phases - 1-Ø or 3-Ø
Sequence¶
Sequence Component transformation. Converts phase quantities into the sequence domain (ABC -> 012). Accepts (and outputs) a Real and Imaginary set of three phase inputs and outputs.
Controls¶
REGFM_A1¶
WIP.
Parameters:
MVA Rating - Rating of the inverter in MVA. Per unit values are calculated on this base.
V Rating - Line to Line voltage rating of the inverter. Per unit values are calculated using this base.
mq - Q-V droop gain
kpv - Proportional gain of the voltage controller
kiv - Proportional gain of the voltage controller
Emax - Upper limit of the output of the voltage loop
Emin - Lower limit of the output of the voltage loop
mp - P-f droop gain
Pmax - Upper limit of the inverter active power output
Pmin - Lower limit of the inverter active power output
kppmax - Proportional gain of the overload mitigation controller
kipmax - Integral gain of the overload mitigation controller
f0 - Rated frequency
TPf - Time constant of the low-pass filter for P measurement
TQf - Time constant of the low-pass filter for Q measurement
TVf - Time constant of the low-pass filter for V measurement
Qmax - Upper limit of the inverter reactive power output
Qmin - Lower limit of the inverter reactive power output
VFlag - 0 or 1
QVFlag - 0 or 1
kpqmax - Proportional gain of the Qmax and Qmin controller
kiqmax - Integral gain of the Qmax and Qmin controller
Imaxf - Inverter maximum transient output current
Xl - Inverter coupling reactance
Other¶
Node Tag¶
Use this block to name nodes and if desired, monitor them. Place this on a circuit node to monitor the voltage or a math node to monitor its value.
Parameters:
Measurement - None or Line-to-Ground or Line-to-Line
Monitor Node¶
Monitor a node. If placed on a circuit node, the voltage will be monitored. If placed on a math node, its value will be monitored.
Parameters:
Measurement - Line-to-Ground or Line-to-Line
Current Measurement¶
Ideal current measurement / current transformer using 100 µ\(\Omega\) shunt.
Parameters:
Phases - 1-Ø or 3-Ø
Node Name¶
Name a node.
Template Component¶
Template component used to create subcircuit blocks.
Python Block¶
Define a function named “func” which will run once per timestep. Put any initialization code outside of this function. The number of input parameters and returns to “func” should match the Num Inputs and Num Outputs. All parameters should be floats. Optionally, the special function “sim_end” may be declared, which will be called once at the end of the simulation.
Parameters:
Num Inputs - 0 or 3 or 23
Num Outputs - 0 or 3 or 12
Call Rate - Specify how frequently to call the Python code in the simulation. Set to Auto to call every timestep (costly).
Python Scope - Set to Auto to keep scope separate from other Python Blocks. Python block with the same scope names will share variables and function names.
Python Code
MATLAB Block¶
Define a single function named “func” which will run at the specified Call Rate. Use a single float input array and single float output array regardless of the number of inputs. See documentation for help setting up MATLAB. MATLAB 2024a or above is required.
Parameters:
Num Inputs - 0 or 1 or 2 or 3
Num Outputs - 0 or 1 or 2 or 3
Call Rate - Specify how frequently to call the MATLAB code in the simulation.
MATLAB Code
Comment¶
For Text
Parameters:
Text - Any text may go here.
Format - Comment or Large Comment or Large Title or Small Title