# Induced EMF without motion?

I have a fixed wire and an electromagnet next to each other, and would like to induce continuous $$\\epsilon\$$ from the change of $$\B\$$ or $$\A\$$. Currently I'm focusing on changing the magnetic field, causing it to increase then decrease and so on(repeatedly) , however, not sure of the outcome of the induced $$\\epsilon\$$ given Faraday's law:

$$\epsilon = \frac{\phi}{\Delta t} = \frac{\Delta (BA)}{\Delta t}$$

If the magnetic field is decreasing say from $$\1Tesla\$$ to $$\0.5Tesla\$$ it's is a negative induced -$$\\epsilon\$$, and when its increasing from $$\0.5Tesla\$$ to $$\1Tesla\$$ that is a positive induced +$$\\epsilon\$$.

This seems to induce AC current? Due to the -V to +V and vice versa.

How can this be converted into DC where there is only +V?

Also, changing the area is another option and seems to give out the same results.

$$\epsilon = -\frac{\Delta\phi}{\Delta t}$$