diplos

Why I ask - Maybe considering laying landscape orientation - with 100mm clearance at bottom of panel?
Depending on the actual roof size:
MPPT 1 90 Deg. with IBR rib for NNE
MPPT 2 In line with IBR rib for NNW

🙂 'holier than the Vatican'..... good one!  Don't hesitate to re-inforce the roof structure with additional tie beams that are connected (bolted) to the current roof- and building  structure, which would then serve to be the anchoring base for the panel structure.  It is of utmost importance that the structure to which the panels will be adhered to, be properly designed, build and affixed in such a way,  that the PV panels won't be considered as structural- or stressed members. In other words, stresses are not allowed to be applied to, or induced into a PV panel. 
Just as important is to mount the panels correctly as per specification of the manufacturer.  All panels have specified mounting positions.  They have been tested to withstand severe windstorms up to a certain windspeed-if installed correctly.

Your stress point is at the top op the panels. Thus the rail should be closer to the top. 
You need vertical legs that move away from the panel as close as perpendicular to the panels. 
Then the mounting bracket needs to be secured to the rafters. If rafters need to be reinforced then add more side by side. 
The wind is also blocked at the lower end. Try for a gap to be added next try. 
Rather get a structural engineer to calculate/design brackets and rafters for you. Let them take into account the forces and wind speeds. This is their field of expertise. This once in many years event is what needs to be taken into account. 
Last point to overrule my thinking out loud.