Reactors, also known as inductors, are widely used in circuits. Due to the electromagnetic induction effect, there is a certain degree of inductance in the circuit, which can prevent current changes. When a conductor is energized, a magnetic field is generated within a certain range of space it occupies, so all electrical conductors that can carry current have a general sense of inductance. However, the inductance of a long and straight conductor is relatively small, and the magnetic field generated is not strong. Therefore, the actual reactor is a wire wound in the form of a solenoid, known as a hollow reactor; Sometimes, in order to make this solenoid have a greater inductance, an iron core is inserted into the solenoid, called an iron core reactor. Reactance is divided into inductive reactance and capacitive reactance, which are scientifically classified as inductors (inductors) and capacitors (capacitors) collectively referred to as reactors. However, due to the existence of inductors in the past and being referred to as reactors, what people now refer to as capacitors is capacitive reactance, and reactors specifically refer to inductors. Classified by structure and cooling medium, connection method, function, and purpose. 1. According to structure and cooling medium, it can be divided into hollow type, iron core type, dry type, oil immersed type, etc., such as dry type hollow reactor, dry type iron core reactor, oil immersed iron core reactor, oil immersed hollow reactor, clamp type dry hollow reactor, wrapped dry hollow reactor, water mud reactor, etc. 2. According to the connection method: it is divided into parallel reactors and series reactors. 3. By function: divided into current limiting and compensation. 4. By purpose: subdivided according to specific purposes, such as: current limiting reactor, filtering reactor, smoothing reactor, power factor compensation reactor, series reactor, balance reactor, grounding reactor, arc suppression coil, incoming reactor, outgoing reactor, saturation reactor, self saturation reactor, variable reactor (adjustable reactor, controllable reactor), yoke current reactor, series resonance reactor Parallel resonant reactors, etc