Harmonics in simulink with controlled voltage source

Hello, I need to have controlled voltage source with adjustable number of harmonics. I want to set magnitude and phase from matlab script. What is the best way for this?

I can connect series of AC voltage source and set their parameters as matrix elements, but it won't allow me to control number of harmonics (because number of AV voltage sources is constant), thus I suppose the controlled voltage source is my option. But how can I generate such a signal in matlab and send it to controlled voltage source?