Generator type of Micro hydroelectric Generator

Micro hydroelectric synchronous generator, carbon brush generator and permanent magnet generator

There are two kinds of Micro hydroelectric Generator for micro hydro turbine station: synchronous generator and induction generator/asynchronous generator. Now people mostly use synchronous generator, only a handful of small capacity is to use asynchronous generators.

Synchronous generator has two kinds:

• one is the traditional synchronous generator of the rotor with excitation winding shaft, slip ring and excitation device, this kind of generator normally with two type of carbon brush excitation generator and brushless excitation generator;
• Another one is permanent magnet synchronous generator(PMG) with the rotor of permanent magnet material.
• Generator also is divided into single-phase generator or three-phase generator. Single-phase generator only two wire transmission, transmission is convenient, but is only applicable to small capacity of generator, now is generally under 55kw for micro hydroelectric generator. Three-phase generator with high efficiency, large capacity and it is suitable for some kind of motorized equipment like compressor, pump etc.

 The structure of the synchronous micro hydroelectric generator of micro hydropower

Micro hydroelectric generator mainly compose with:

1. Micro hydroelectric Generator stator, including stator core, stator winding, base, junction box, etc.;
2. Micro hydroelectric Generator rotor, including the rotor core, magnetic pole, exciting winding, rotor, slip rings, carbon brush, blades, etc.;
3. Micro hydroelectric Generator end cover, including the front and back end cover, bearing cap and brush device, etc.;
4. Micro hydroelectric Generator excitation device.

Micro hydroelectric Generator is composed of stator and rotor of two parts, including the stator core of the stator, the stator coil and frame sections and stator core is fixed on the frame.

Three-phase generator stator coil with A, B, C three-phase, electrical Angle 120 ° apart each other, each phase coil has two end, there are six points in three-phase.

• generally A phase end with that symbol D1, D4;
• B phase end with that symbol D2, D5;
• C phase end with symbol D3, D6.
• Smaller generators typically uses star line connection, D1, D2, D3, three-phase line for ABC, D4, D5, D6 connect a neutral line, becomes a three phase four wire Micro hydroelectric Generator system power supplying lines. Rotor including the rotor iron core, excitation coil, and through the core shaft parts, at one end of the shaft with the slip ring and brush, by the excitation source of direct current (dc) can pass the carbon brush and slip ring into a magnetic field pole coil.

This kind of generator with slip rings, carbon brush friction parts, require constant maintenance and excitation device of the rectifier element is also easy to damage, accessories should be prepared at ordinary times, so HS Dynamic Energy here only offer Brushless synchronous type Micro hydroelectric Generator for our customer without using such kind of carbon brush unit, and don’t need to worry about this problem.

Some small self-excited constant-voltage synchronous generator pole coil is installed on the frame is not rotating, produce a phase alternating current coil is rotating, known as the rotating armature of synchronous generator, the structure of this generator with small capacity.

Permanent magnet synchronous generator of Micro hydroelectric Generator

Structure between permanent magnet synchronous generator and normal synchronous generator are basically the same, the biggest difference is that permanent magnet synchronous generator only has the permanent magnets on the rotor and without the magnetic coil, slip ring, excitation device; that is just with the rotor’s permanent magnet. It may reduce a lot of failure and higher reliability. This kind of generator cost is higher than common synchronous generators as carbon brush type, but its reliability is greatly increased. The technology behind the remote areas of the user use is very good and important, because the remote user maintenance cost is very high.

Go to know more about HS Dynamic Energy’ Micro water turbine Generator