How can I ensure a bidirectional signal flow using physical signals and calculations in Simscape?

Hello everyone,

My goal is to write Model representing a transformer for a 3 phase voltage. In order to do so, I have to use the space-vector transformation (Clarke, Park) to use the given equivalent circuit diagram.

The problem: the model has to allow bidirectional information flow. Is there any way to do this?

In my mind one way would be the following: Write a new simscape Model, in which i put the calculations for the transformations in the "function setup" section. I then use these results under the "equations" sections. I fear I will thereby destroy the bidirectional signal flow.

I could also do my calculations in the "equations" section, but I think it will give me an error message.

It is very important that the model will work not only have a unidirectional signal flow.

I really hope I could explain my problem in an understandable way. I would deeply appreciate some good ideas and help! Thanks to everyone in advance!

EDIT:

This is the code I wrote so far:

component Clarke
%abc/alpha-beta
%
%Clarke Transformation
%

    nodes
        a = foundation.electrical.electrical; % in u1 :left
        b = foundation.electrical.electrical; % in v1 :left
        c = foundation.electrical.electrical; % in w1 :left

        u_alpha = foundation.electrical.electrical; % out u2 :right
        u_beta = foundation.electrical.electrical; % out v2 :right

    end

    variables(Hidden=true)
        u_a = {0, 'V'}; %Spg
        u_b = {0, 'V'}; %Spg
        u_c = {0, 'V'}; %Spg
        u_out = {0, 'V'}; %Spg
        i1_u = {0, 'A'}; %Strom u1
        i1_v = {0, 'A'}; %Strom v1
        i1_w = {0, 'A'}; %Strom w1
        i2 = {0, 'A'}; %Strom u2
        end

    branches
  i1_u: a.i -> b.i;
  i1_v: b.i -> c.i; 
  i1_w: c.i -> a.i; 
  i2: u_alpha.i -> u_beta.i; 
    end
    equations
        u_a == a.v - b.v;
        u_b == b.v - c.v;
        u_c == c.v - a.v;

        u_out == u_alpha.v - u_beta.v;

        u_out == 2/3*(u_a+ u_b * cos( (2/3) *pi ) + u_c * cos( (4/3) *pi ) + 1i * (u_b * sin( (2/3) *pi ) + u_c * sin( (4/3) *pi )  ));

 end
end

The message I get is the following: Number of variables exceeds number of equations.

I expected a problem because I changed a physical signal to a mathematical equation which does not exist in physics. Any suggestions?