Braking wind speed generally has only two aspects, one is the safe wind speed, and the other is the wind speed that reaches magnetic saturation and cannot generate electricity.
Safe wind speed is a structural characteristic of the fan. When the wind speed is high and the vibration is severe, it will cause damage.
The wind speed without generating electricity is the nominal cut-out wind speed. Because the rotation speed is fast, a large amount of heat will be generated under the action of magnetism, which in turn affects the performance of the magnets. In addition, the generated current is large, which acts inversely on the magnets, thus achieving a balance, unable to generate electricity.
The efficiency of AC permanent magnet generator is actually only about 50%, generally 65-80%. When the magnet speed is above 400/min, it is more than 80% under light load. It depends on this. The magnet material used in the generator generally rotates at 1,000 revolutions per minute. It will output full power only when the water power and rated speed are met. The experiment you mentioned shows that the voltage is constant at more than 50 volts, and the current fluctuates greatly, and it is periodic. 'I don't know what the rated voltage, speed and model are indicated on the signboard. The current changes with the load power and speed. Inductive loads are different from purely resistive loads. To accurately measure the data, I recommend using six Diodes form a three-phase full-wave rectifier, and with the same DC load, if you use 1000W, the power will drop a lot, which means that your water power and speed cannot be reached. From what I can infer, your water power is not up to par. Measure the benefits to see if the problem lies in the turbine or the generator itself. Since the application places of this type of generator are different from ordinary generators, its technical requirements have its own particularities, and their performance must be good with wind turbines. Matching, at 65% of the rated speed, the no-load voltage of the generator should not be lower than the rated voltage; at 150% of the rated speed, the generator should be able to run overloaded for 2 minutes at the rated voltage; under no-load conditions, the generator should It can withstand 2 times the rated speed for 2 minutes, so pay attention to safety when operating at high speed and with light load.
Commonly used small (within 1kw) low-speed generators (within 300 rpm). The wind wheel of this device is directly coupled to the generator shaft. The wind drives the wind wheel to rotate and converts wind energy into mechanical energy. , the wind wheel drives the generator to rotate, converting the mechanical energy into electrical energy, which is also output after gear acceleration and rectification. The main manufacturers include Shanghai Micromotor Research Institute, Guangxi Liuzhou Liuzhengfa Power Distribution Equipment Factory, especially my company In Shenzhen, there are many rare earth magnets called "NdFeB magnets" with high magnetic energy product, which are called the contemporary "King of Permanent Magnets". Permanent magnet generators made of high-carbon and strong magnetic steel are particularly good and highly efficient.
When the speed of a permanent magnet generator is higher, the voltage and power are higher. When the speed, power, and temperature are higher than the rated values, the magnetic saturation occurs, and the efficiency curve decreases. It's a bit cold today, so I'm replying to you from bed, so it's inconvenient to make curves. If you really need it, call me at 157621910. I hope the above rough description is of some use to you.