Think of it like you get electric energy circuits coming through the head (along with the cosmic and "crown chakra" energies from the Universe)...and magnetic circuits are coming through the feet and work through the "base chakra" at the bottom of the torso. (they join at the heart to make an electro-magnet if you didn't know)
Excess electric or magnetic can happen for a variety of reasons; you're building your energy system so fast that the energy simply doesn't have anywhere else to go (eg. your storage centers are maxed out, even though they are expanding to hold more capacity, you're probably taking quantum leaps in your practice--going so fast that you're several steps ahead of where you're body is at--not at all a bad thing, but it helps to "ground")...and it can get slightly annoying at times when you start shocking everything.
I've have this now and then, perhaps I have a slightly more estranged case of it (I used to break electronics--gone through a few computer monitors until I got a handle on it).
What you might want to do is go outside barefooted (if you can) and just stand on the earth and relax completely(tension locks electricity in the muscles of course)...while standing, feel the straightness of your spine, feel like your feet and tailbone goes all the way down to the core of the earth "rooting" with it, and then feel as if your head is almost hung by a string from somewhere above in the stars.
Visualize and feel your energy connecting down to the core of earth. Feel the dantien spinning very, VERY fast and shining very bright--do that for a few minutes then do your active exercies or do a closing. This helps ground your "excess electric circuits" and also helps "ground" your magnetic circuits. It will also open your energy even more so to the earth as well as the Universe, and assist in expanding your energy capacity. You should feel energized when you're doing this. Make mental notes of times if you "get tired" and read where the energy is going.
Like most all energy types, excess electric or magnetic Qi "isn't bad" but it can be annoying (or expensive if you're breaking stuff) and it does feel nice to be grounded.
Hope this helps.
~Z