因为已经复习了变压器原理,以及基本感性、容性和电阻性电路,所以,下面我们将讨论用于电缆电视系统中的电源系统。用于前端电子装置中的电源经常使用来自115V_(ac)市电的电源,而电缆电视分配系统的线路放大器经常使用由电缆提供的60V_(ac)准方波电源。60V_(ac)电缆电视电源基本上是一个由115V_(ac)商用电源激励的铁磁谐振变压器,这种115V_(ac)商用电源对电源插入器提供已稳压(基本恒定)的60V。以下章节中将较详细地讨论这种电源。 Since we have reviewed the transformer principle and the basic inductive, capacitive, and resistive circuits, we will discuss the power systems used in cable television systems below. Power sources used in front-end electronics often use power from 115V ac mains, while line amplifiers in cable television distribution systems often use 60V ac quasi-square power provided by the cable. The 60V ac cable television power supply is basically a ferroresonance transformer energized by a 115V ac commercial power supply that provides a regulated (substantially constant) 60V to the power interposer. This power supply will be discussed in more detail in the following sections.