请看例句：
e.g.Compared with his bike,mine looks better.
跟他的自行车比起来,我的看起来好多了.
这里compared with前省略了When my bike is.这样就能解释,为什么compare后面加d了.
e.g.You can never compare yourself with him.
你永远不能和他相提并论.
这里compare with是主动式,因此不加d.
补充例句：
To compare your parents with Ann's,you need to make yourself dream at first.
想把自己的父母和安的父母做比较,你先做个梦吧.哈哈,开个玩笑啦～
希望解释是你需要的～也就是说compared with 前面省略了。。。be...，所以他还是被动语态？其实是这样的（When my bike is ）compared with his bike...括号里的省略了，也就是把be动词省略了，实际上他还是be compared with这个被动结构～