Both techs are based on Star Fleet Battles weapon systems.
From section FP1.0 of the Captain's edition of SFB, 1990.
A plasma torpedo is a ball of matter on the brink of being converted totally to energy. The weapon is extremely powerful. It is used by the Romulans and Gorns as well as the Orion pirates and (in Module C2) by the Interstellar Concordium. There are several different types of this weapon, each with different warhead strengths and energy costs.
Basically the plasma torp is a multi-turn charging seeking weapon. It can be disrupted by defensive fire, reducing the warhead strength.
From section D10.0 of the Captain's Module C2, 1991.
The Andromedans do not use shields. Instead they use power absorber (PA) panels. These absorb the energy of enemy weapons (up to a limit) and prevent it from damaging the ship. This stored energy can then be channeled into the ship's batteries. A given ship cannot have both shields and PA panels; the two systems are mutually exclusive and cannot work together.
As the quote says, they absorb incoming damage and allow it to be used by the mounting ship. They can be overloaded, taking more damage than they can absorb. This gets applied as damage normally.
Now the Aurora systems work somewhat similarly to these.
And yes, I have SFB within arms reach of my computer desk