电能是现代社会最主要的能源之一。发电机组是将其他形式的能源转换成电能的机械设备,它由水轮机、汽轮机、柴油机或其他动力机械驱动,将水流,气流,燃料燃烧或原子核裂变产生的能量转化为机械能传给发电机,再由发电机转换为电能。发电机在工农业生产,国防,科技及日常生活中有广泛的用途。
一般我们常见的发电机组通常由以下几个:汽轮机、水轮机或内燃机(汽油机,柴油机等发电机)驱动、风能、太阳能、生物质能、海洋能等。柴油发电机的市场最大,主要是由于柴油发电机组的容量较大,可并机运行且持继供电时间长,还可独立运行,不与地区电网并列运行,不受电网故障的影响,可靠性较高。尤其对某些地区常用市电不是很可靠的情况下,把柴油发电机作为备用电源,既能起到应急电源的作用,又能通过低压系统的合理优化,将一些平时比较重要的负荷 在停电时使用。因此在工程中得到广泛的使用。
发电机的形式很多,但其工作原理都基于电磁感应定律和电磁力定律。因此,其构造的一般原则是:用适当的导磁和导电材料构成互相进行电磁感应的磁路和电路,以产生电磁功率,达到能量转换的目的。
发电机的分类:
发电机 直流发电机、交流发电机、 同步发电机、异步发电机(很少采用);交流发电机还可分为单相发电机与三相发电机。
发电机通常由定子、转子、端盖及轴承等部件构成。定子由定子铁芯、线包绕组、机座以及固定这些部分的其他结构件组成。定子的功用是产生交流电。转子由转子铁芯(或磁极、磁扼)绕组、护环、中心环、滑环、风扇及转轴等部件组成。转子的功用是产生磁场。安装在定子里边。
原理由轴承及端盖将发电机的定子,转子连接组装起来,使转子能在定子中旋转,做切割磁力线的运动,从而产生感应电势,通过接线端子引出,接在回路中,便产生了电流。
Electricity is one of the most important energy sources in modern society. A generator set is a mechanical device that converts other forms of energy into electrical energy. It is driven by water turbines, steam turbines, diesel engines, or other power machinery to convert the energy generated by water flow, air flow, fuel combustion, or nuclear fission into mechanical energy and transmit it to a generator, which then converts it into electrical energy. Generators have a wide range of applications in industrial and agricultural production, national defense, technology, and daily life.
The commonly used generator sets are usually driven by the following: steam turbine, water turbine, or internal combustion engine (gasoline engine, diesel engine, etc.), wind energy, solar energy, biomass energy, ocean energy, etc. The market for diesel generators is the largest, mainly due to the large capacity of diesel generator sets, which can operate in parallel and maintain power supply for a long time. They can also operate independently and are not parallel to the regional power grid. They are not affected by power grid failures and have high reliability. Especially for some areas where the commonly used mains power is not very reliable, using diesel generators as backup power sources can not only serve as emergency power sources, but also optimize the low-voltage system to use some important loads during power outages. Therefore, it has been widely used in engineering.
There are many forms of generators, but their working principles are based on the laws of electromagnetic induction and electromagnetic force. Therefore, the general principle of its construction is to use appropriate magnetic and conductive materials to form magnetic circuits and circuits that induce each other electromagnetically, in order to generate electromagnetic power and achieve energy conversion.
Classification of generators:
Generator DC generator, AC generator, synchronous generator, asynchronous generator (rarely used); AC generators can also be divided into single-phase generators and three-phase generators.
A generator is usually composed of components such as stator, rotor, end cover, and bearings. The stator is composed of the stator core, wire winding, machine base, and other structural components that fix these parts. The function of the stator is to generate alternating current. The rotor is composed of components such as the rotor core (or magnetic pole, magnetic choke) winding, guard ring, center ring, slip ring, fan, and shaft. The function of a rotor is to generate a magnetic field. Installed inside the stator.
The principle is to connect and assemble the stator and rotor of the generator through bearings and end caps, so that the rotor can rotate in the stator and perform the motion of cutting magnetic field lines, thereby generating induced potential. It is led out through the terminal block and connected to the circuit, generating current.