1, magnetic field properties. The permanent magnet motor can maintain the magnetic field without external energy after it is made; Ordinary motors need current to generate magnetic fields.
2. Rotor structure. A permanent magnet pole is arranged on the rotor of the permanent magnet motor; The excitation coil is installed on the rotor of a common motor.
3. Applicable occasions. Permanent magnet motors are usually used in low power occasions; Ordinary motors, especially excitation motors, are often used in high-power occasions.
Motor refers to an electromagnetic device that realizes electric energy conversion or transmission according to the law of electromagnetic induction. It is represented by the letter M in the circuit, and its main function is to generate driving torque as the power source of electrical appliances or various machines.
Permanent magnet motor is a kind of motor which uses permanent magnets to establish magnetic field.
Question 2: What is a permanent magnet motor? Compared with electrically excited motors, permanent magnet motors, especially rare earth permanent magnet motors, have the advantages of simple structure and reliable operation. Small size and light weight; Low loss and high efficiency; The shape and size of motor can be flexible and diverse, so it has a wide range of applications, covering almost all fields of aerospace, national defense, industry and agriculture, production and daily life.
This book is the collation and summary of the scientific research results of permanent magnet motor research and development in Shenyang University of Technology in recent ten years. This book expounds the research and analysis methods of permanent magnet motors suitable for computers in recent years, mainly based on the analytical solution of equivalent magnetic circuit, combined with modern design methods such as numerical calculation of electromagnetic field. This book analyzes the working principle, structure, calculation method and design characteristics of many basic types of modern permanent magnet motors. This book focuses on permanent magnet motors, but its basic contents are also applicable to other permanent magnet motors such as Al-Ni-Co permanent magnets and ferrite permanent magnets.
This book strives to implement the principle of integrating theory with practice, not only to clarify the basic principles and concepts, but also to provide basic formulas, reference data and curves needed in design, manufacture and operation, and at the same time to reflect the new technologies, new achievements and practical application trends of permanent magnet motors. There are four basic types of permanent magnet motors and practical electromagnetic computer programs and examples. Here are two kinds of permanent magnet motor electromagnetic computer source programs.
This book can be used as a reference for scientific and technical personnel engaged in the research, design, manufacture, test and operation of permanent magnet motors. It can also be used as a teaching material for graduate students majoring in electrical machinery and electrical appliances in colleges and universities; It can also be used as teaching reference books or continuing education materials for teachers, students and related technicians majoring in electrical engineering and automatic control.
Question 3: What permanent magnet generator 5 points Chinese name: permanent magnet generator English name: permanent magnet generator definition: a generator with permanent magnet excitation instead of electric excitation. There are no excitation windings, brushes and slip rings. Permanent magnets are generally arranged on the rotor, and permanent magnet generators are usually used as auxiliary exciters for turbo-generators.
See: baike.baidu/view/549871.
Question 4: What is a permanent magnet alternator? The rotor itself is a magnet, and the generator itself generates alternating current, which needs to be obtained through a rectifier.
Question 5: What are the advantages of permanent magnet generators? A permanent magnet generator refers to a generator that generates an excitation magnetic field by a permanent magnet. Permanent magnet is not only a magnetic source, but also a part of motor magnetic circuit. Permanent magnet generators have the following advantages: 1. Simple structure and high reliability. The permanent magnet generator omits the structure of excitation winding, brush and slip ring, and the whole machine is simple in structure, which avoids the shortcomings of easy burning of excitation winding and easy wear of brush and slip ring of excitation generator, and has reliable performance. The permanent magnet generator with small volume and high specific power adopts simplified rotor structure, including parallel magnetic field structure and series magnetic field structure. The rotor with parallel magnetic field structure is cast and pressed, with embedded permanent magnets and high speed. The rotor with series magnetic field structure adopts steel structure, and permanent magnets are embedded in the surface, so the rotor surface has strong magnetic induction and the overall structure is firm and reliable. Due to the simplification of the rotor structure, the internal structure of the generator is compact, the moment of inertia of the rotor is small, and the practical speed is improved, so the specific power (the ratio of power to volume) is improved. 3 Good low-speed power generation performance The permanent magnet generator has good low-speed power generation performance and high output power. When idling, the output power of permanent magnet generator is twice that of excitation generator. 4. High efficiency and energy saving. Generally, the average efficiency of an excited generator is only about 50% in the speed range of 1500~6000r/min. The average efficiency of permanent magnet generators can reach 75% ~ 80%. So the permanent magnet generator is more energy-saving. 5. High voltage stabilizing accuracy can prolong the service life of the battery. The permanent magnet generator adopts the mode of switching rectification and voltage stabilization, and uses small current pulse charging, which avoids the possibility of damage to the battery caused by overcurrent charging and can prolong the service life of the battery. 6. There is no wireless interference. There is no brush, slip ring and electric spark in the operation of permanent magnet generator. Therefore, there is no wireless interference and the performance is greatly improved. However, due to the high price of rare earth permanent magnet materials, the manufacturing cost of permanent magnet generators is generally higher than that of excitation generators, and the price of the whole machine is relatively higher.
Question 6: What are the advantages of permanent magnet generators? Permanent magnet is not only a magnetic source, but also a part of motor magnetic circuit. Permanent magnet generators have the following advantages:
1, simple structure and high reliability.
The permanent magnet generator omits the structure of excitation winding, brush and slip ring, and the whole machine is simple in structure, which avoids the shortcomings of easy burning of excitation winding and easy wear of brush and slip ring of excitation generator, and has reliable service performance.
2. Small size and high specific power.
The permanent magnet generator adopts simplified rotor structure, including parallel magnetic field structure and series magnetic field structure. The rotor with parallel magnetic field structure is made by casting and pressing, and permanent magnets are embedded in it, which has high speed. The rotor with series magnetic field structure adopts steel structure, and permanent magnets are embedded in the surface, so the rotor surface has strong magnetic induction and the overall structure is firm and reliable. Due to the simplification of the rotor structure, the internal structure of the generator is compact, the moment of inertia of the rotor is small, and the practical speed is improved, so the specific power (the ratio of power to volume) is improved.
3. Good low-speed power generation performance
The permanent magnet generator has good low-speed power generation performance and high output power. When idling, the output power of permanent magnet generator is twice that of excitation generator.
4. High efficiency and energy saving
Generally, the average efficiency of an excited generator is only about 50% in the speed range of 1500-6000 r/min. The average efficiency of permanent magnet generators can reach 75% ~ 80%. So the permanent magnet generator is more energy-saving.
5. High voltage stabilizing accuracy can prolong the battery life.
The permanent magnet generator adopts switching rectifier and voltage stabilizing mode and small current pulse charging, which avoids the possibility of battery damage caused by over-current charging and can prolong the service life of battery.
6. No wireless interference
The permanent magnet generator has no brush, no slip ring and no electric spark in operation, so there is no wireless interference and its performance is greatly improved.
However, due to the high price of rare earth permanent magnet materials, the manufacturing cost of permanent magnet generators is generally higher than that of excitation generators, and the price of the whole machine is relatively higher.
Question 7: What do you mean by an integrated generator with permanent magnets? The generator adopts permanent magnet rotor structure and uses armature claw to control output voltage, which has high reliability. It is installed on small motor vehicles without batteries as lighting and signal power supply, and the voltage is basically unchanged when the engine speed changes for 3 ~ 4 times. Especially when the vehicle is driving at a low speed, better lighting effect can be obtained.
The utility model relates to an integrated permanent magnet constant voltage generator for tractors. The motor consists of rotor, stator and control module. The rotor is an excitation rotor composed of permanent magnets, and the stator is a conventional stator. The control module has a zero current blocking electronic parallel regulating circuit, which is integrated with the generator. The motor can still output rated voltage at the lowest working speed of tractor, with novel structure, reliable operation and low cost.
Question 8: The difference between permanent magnet motor and permanent magnet synchronous motor Broadly speaking, permanent magnet motor refers to the motor using permanent magnets. This kind of motor does not need excitation, which can be roughly divided into: permanent magnet DC motor (with commutator), brushless DC motor (DC motor characteristics, electronic commutation), permanent magnet synchronous motor (AC motor characteristics) and so on.
Permanent magnet synchronous motor is just a classification of permanent magnet motor.
In addition, the classification of motors can be analyzed from many angles. In principle, it can be roughly divided into three categories: voltage control (direct torque control), such as brushed DC motor and brushless DC motor; Frequency control (direct speed control), such as induction motor and synchronous motor; Magnetic field frequency control (using alignment principle), such as stepping motor.
Question 9: What is a permanent magnet motor? What is an excitation motor? What is the difference? What are their advantages? Thank you. A permanent magnet is a permanent magnet motor, and an excitation coil is an excitation motor.
Permanent magnet motor itself can provide enough magnetic field without consuming energy, but excitation motor needs to convert external energy into magnetic field through excitation coil to provide enough magnetic field, so its efficiency is relatively low. The efficiency of permanent magnet motor can reach above 90%.
Excitation motor also has its advantages, that is, the manufacturing cost is relatively low and the process is simpler than that of permanent magnet motor, so in the ordinary market, excitation motor is widely used now.
If you don't understand upstairs, you don't have to pretend to understand. Synchronous motor means that the rotating magnetic field speed of the excitation motor is synchronized with the rotor speed of the motor in the working state. Asynchronous motor means that the rotating speed of magnetic field is ahead of the rotating speed of rotor by a certain amount, but the rotating speed of rotor is the same as that of magnetic field.
Question 10: Efficiency of permanent magnet generators Let's talk about some excitation winding generators. The DC power used by the excitation winding is supplied to the excitation winding after rectification of the main winding, thus generating a magnetic field, which will consume a certain amount of electric energy of the main winding. If this magnetic field is replaced by a magnet, this part of electric energy will be saved, so more electricity will be transmitted to the outside and the efficiency will be higher. This kind of generator is generally used in places with low power, with simple structure and not easy to break down.