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The Power System Toolbox consists of 3phase components for power system studies (short circuit and fault analysis and relay protection). Key elements are the LINE3 component that are drawn and edited like Connections and the various phasor calculators based on MODELS.

Fundamental components
These are the building blocks in power system studies with easy fault application. Combine this with the standard voltage and current probes with steadystate output.
Selection 
Object name 
Icon 
ATP card 
Description 
Bus 
BUS3 
BRANCH 
Multinode (Bays) connection point with optional load and arrester. 

Line 
LINE3 
BRANCH 
LINEPI3S or LINEZT_3 component with faults, CB and CT. Edited like Connections. 

Load PQ 
LOADPQ 
MODELS RLC+SRC 
Voltage dependent load model. Group with MODELS controlled source based on phasor calculation 

Ctrl CB 
CTRLCB 
MODELS SWITCH 
3phase TACS switch, opens at MODELS controlled zero crossing 
Basic MODELS calculators
These calculators takes in 3phase current or voltage chosen in the input node (left) dialog box.
Selection 
Object name 
Icon 
ATP card 
Description 
RMS 
ABC2RMS 
MODELS 
Outputs RMS value of all 3phase inputs 

Phasors +Basic 
ABC2PHR 
MODELS 
Outputs phasors (re, im) for all 3phase inputs. DFT recursive or FFT methods with down sampling. 

Phasors +Initialized 
ABC2PHRI 
MODELS 
Same as ABC2PHR but with steadystate initialization at t=0 

Phasors +Freq. variant 
ABC2PHRF 
MODELS 
Same as ABC2PHR but with frequency as input (from PLL) 

Phasors +1+h 
ABC2PHRH2 
MODELS 
Calculate phasors (re, im) in fundamental frequency and one extra harmonic. 

Phasors +Sequence 012 
ABC2SEQ 
MODELS 
Calculate phasors and convert it to sequence 012 output (re, im). 

Phasors +Write/Plot 
WRITEPHASOR 
MODELS 
Takes in phasors (re, im) to View this at specific instance in time 

Filters +Low pass 
BLPFILT 
MODELS 
03 order Butterworth low pass filter with gain adjustment 

Filters +High pass 
BHPFILT 
MODELS 
03 order Butterworth high pass filter with gain adjustment 

PLL 
PLLDQ 
MODELS 
Calculation of frequency based of park transform of 3phase inputs 

Harmonics 
HARMONICS 
MODELS 
Calculation of 126 harmonics based on DFT recursive alg. Old. 
Power and RX calculators
These calculators require input of 3phase currents and voltages (topleft node is voltage, bottomleft node is current). Normally the two input nodes can simply be connected and further to a unique 3phase switch node, as shown in Fig. 4.86 . Note that currents can only be obtained from switches and ATP will give you the current in the first switch connected to the node you specify. To make sure you get the correct current in the case of several switches connected to the same bus, you should connect to a node not shared by any other switch with a different current. The current probe with Add current node adds two measuring switches in series behind the scene and gives you access to the unique middle point.
Selection 
Object name 
Icon 
ATP card 
Description 
PQ +PQ 3*1 
UI2PQ 
MODELS 
Calculate active and reactive power per phase for 3phase volt and curr. 

PQ +PQ 3phase 
UI2PQ3 
MODELS 
Calculate active and reactive 3phase power. DFT+FFT+DQ alg. 

PQ +Watt meter 
WMETER 
MODELS 
Calculate average active power by integral method. No downsampl. 

RX + (UaUb)/(IaIb) 
UI2RXL 
MODELS 
Calculation of positive sequence impedance (R, X) for phasetophase faults. 

RX + (UaUb)/(IaIb) 
UI2RXE 
MODELS 
Calculation of positive sequence impedance (R, X) for phasetoground faults. 

RX +Ua/Ia 
UI2RX 
MODELS 
Calculates the impedance seen in each phase 
Protective relays
These relays should be connected to RMS (over current, and under/over voltage), Phasor calculators (differential), and RX calculators (distance). The directional overcurrent relay has its own zero sequence phasor calculator, and the frequency relay requires frequency input. The user must click on the input node of the models to make sure the correct signals are recorded. The relays using signals from other models has default input from models and must be ordered after the model producing the signals. Sorting by order was previously the only option to accomplish this, but ATPDraw v7 offers an option EditArrangeSort all Models to help ordering correctly. All the relays has a blocking control signal input, trip signal and trip zone information outputs. In the dialog window the user sets the zone characteristics and there is also View option that plots the zones and recorded trajectories (with down sampling) until trip. The W1RELAY21P component also has a zone helper.
Selection 
Object name 
Icon 
ATP card 
Description 
Relays +Overcurrent 50/51 
W1RELAY51 
MODELS 
Based on rms input and a definite time zone gives a trip signal out. Blocking option available. Zone output not relevant. 

Relays +Time overcurrent 
W1RELAY51I 
MODELS 
Based on rms input and standardized inverse time zone gives a trip signal out. 

Relays +Dir. Ground 67N 
W1RELAY67N 
MODELS 
Current and voltage input with internal zero sequence phasor calculation. Trips is V0>Vlim and I0 in zone relative to V0. 

Relays + Distance quad 21 
W1RELAY21P 
MODELS 
Input from RX calculator. Three delayed zones with 4 points. Zone helper available. 

Relays + Distance circ 21 
W1RELAY21C 
MODELS 
Input from RX calculator. Three delayed zones with mho characteristic. 

Relays +Diff transf. 87T 
W1RELAY87T 
MODELS 
Input from current phasors 1+h. Calc. differential current with turns ratio, phase shift scaling and harmonic blocking (inrush). Current into unit on both sides. 

Relays +Diff line 87L 
W1RELAY87L 
MODELS 
Input from current phasors 1+h. Calc. differential current with time delay compensation and harmonic blocking. Current into unit on both sides. 

Relays +Undervoltage 27 
W1RELAY27 
MODELS 
Input from rms voltage. Two undervoltage zones with time delays and 3 different standard characteristics. 

Relays +Overvoltage 59 
W1RELAY59 
MODELS 
Input from rms voltage. Two overvoltage zones with time delays and 3 different standard characteristics. 

Relays +Frequency 81 
W1RELAY81 
MODELS 
Input from frequency calculator. Two zones for both under and over frequency with fixed time delay. 
TACS
Selection 
Object name 
Icon 
ATP card 
Description 
TACS +RMS 
TABC2RMS 
TACS 
3phase RMS calculator. DEVICE66 

TACS +Freq 
TABC2FRQ 
TACS 
3phase frequency calculator. DEVICE50 

TACS +DQ0 
TABC2DQ0

TACS 
3phase park transform calculator. 

TACS +alphabeta 
TABC2ABG 
TACS 
3phase alphabeta transform calculator. 