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PSCAD simulation model is shown below figure,

Definition of Transmission line AB

Definition of Transmission line BC

Definition of transmission line BD
Comparison of voltages in each substation with the results got from Bewley Lattice Diagram and simulation results are shown in below,
Substation A

Substation B

Substation C

Substation D

When we compare simulation results with the graphs we got using Bewley lattice diagram there are some differences we can see. Although when we draw our graphs using Bewley lattice diagram, we tend to draw step wise voltage increment or decrement, in real simulation due to inductance and capacitance presence the voltages cannot changes instantly. Hence the simulation graphs have very small ramp type voltage changes rather than purely step wise changes.
The other differences may be occurred due to following reasons,
When we draw Bewley Lattice Diagram, for the calculation we take round off values. Hence the final output may be effect from those rounding offs which is not present in simulation process. Specially when we take the time constant, depend on the rounding off value the Bewley Lattice Diagram changes significantly so the voltages values also change according to that.
In manual calculation method of over voltages (Bewley Lattice Diagram), human errors can be occurred. And once there is an error occurred it will effect to the subsequent results also. But in PSCAD simulation process the effect from human errors are very minimum
Using of Bewley Lattice Diagram is getting significantly complex when the numbers of substations are increase. So due to complexity, it is very difficult to draw the Bewley Lattice Diagram beyond certain time period. But with the presence of simulation packages we can simulate any number of substations transient behavior for any time duration.
Current values of substations are shown following figures,
At substation