The starter motor on the excavator is an important component of the excavator power system. They are responsible for starting the excavator engine and ensuring that the excavator can start and operate smoothly under various working conditions. The following is an introduction to several common starting motors on excavators:
1. Three phase asynchronous motor
Working principle: A three-phase asynchronous motor is a type of motor that is powered by a 380V three-phase AC power supply simultaneously. It rotates in the same direction but at different speeds as the stator rotating magnetic field, resulting in a slip rate, hence it is called a three-phase asynchronous motor.
Structure: Mainly composed of stator, rotor, bearings, outlet box, etc.
Characteristics: Three phase asynchronous motors have the advantages of simple structure, reliable operation, and easy maintenance. It is suitable for starting excavators with various power and speed requirements.
2. Permanent magnet synchronous motor
Working principle: The permanent magnet synchronous motor uses the magnetic field of the permanent magnet to establish magnetic field interaction with the current, causing the rotor to rotate and drive the excavator to move.
Characteristics: Permanent magnet synchronous motors have advantages such as high efficiency, high power factor, and high torque density. It is one of the most commonly used types of motors for pure electric excavators.
3. AC asynchronous motor
Working principle: The working principle of an AC asynchronous motor is to use the electromagnetic induction effect of current between the rotor and stator to generate torque, thereby driving the excavator to move.
Characteristics: AC asynchronous motors are suitable for industrial applications with low power and large speed changes. It has the advantages of simple structure and relatively low price.
4. DC motor
Working principle: The working principle of a DC motor is to use the interaction between magnetic flux and current to generate torque, thereby driving the excavator to move.
Characteristics: DC motors have advantages such as high starting torque and good speed regulation performance. It is suitable for situations that require quick start and reverse, such as certain auxiliary equipment of excavators.
5. Servo motor
Working principle: A servo motor is a special type of motor that can achieve precise position, speed, and force control by controlling current and voltage.
Features: Servo motors have advantages such as high precision, high response speed, and high stability. Used in some modified electric excavators, it has higher energy efficiency compared to ordinary motors.
6. Explosion proof motor (explosion-proof motor)
Working principle: The working principle of explosion-proof motors is similar to that of ordinary motors, but special explosion-proof measures are adopted in their design and manufacturing process.
Features: Explosion proof motors can operate safely in flammable and explosive gas environments. It is usually used in places with explosive hazards such as coal mines, metal mines, non-metallic mines, etc.
matters needing attention
Choosing the appropriate motor: When selecting the starting motor for an excavator, it is necessary to choose the appropriate motor based on the model, power, speed, working environment, and usage requirements of the excavator.
Maintenance: Regularly maintain the starter motor, including checking the appearance of the motor, cleaning the motor surface, lubricating bearings, etc., to ensure the normal operation of the motor and extend its service life.
Fault handling: In case of motor failure or abnormal situation, the machine should be stopped for inspection in a timely manner and professional maintenance personnel should be contacted for maintenance and handling.
In summary, there are various types of starting motors on excavators, each with its own characteristics. When selecting and using, comprehensive consideration should be given to the actual situation to ensure the normal operation and efficient operation of the excavator.
The common starting motors on excavators, such as three-phase asynchronous motors, permanent magnet synchronous motors, DC motors, and servo motors, each have unique advantages and disadvantages. The following is a detailed analysis of the advantages and disadvantages of these motors:
Three phase asynchronous motor
advantage
Simple structure: Three phase asynchronous motors do not have complex components such as rectifiers, and their structure is relatively simple, making them easy to manufacture and maintain.
High reliability: Three phase asynchronous motors have a long service life, low failure rate, can work in harsh environments, and have high reliability.
Stable operation: The three-phase asynchronous motor runs smoothly with low noise and is not easily affected by load changes that affect its performance.
Strong adaptability: Three phase asynchronous motors can adapt to different power and speed requirements, and are widely used in various fields such as industry, transportation, and household appliances.
shortcoming
Low power factor: When the load is small, the power factor of three-phase asynchronous motors is lower.
High starting current: When starting a three-phase asynchronous motor, a large current is required, which can easily cause impact on the power grid.
Low efficiency: usually around 80%, compared to other types of motors, the efficiency is lower.
Poor speed regulation performance: The speed regulation range is narrow and not suitable for situations that require high-precision control.
Permanent magnet synchronous motor
advantage
Small size and light weight: The rotor and stator of the permanent magnet synchronous motor are made of lightweight materials, making the entire motor lighter in weight and relatively smaller in size.
Good operational stability: It can maintain high efficiency even at high speeds and has good operational stability.
Low noise: The noise generated during operation is relatively low, suitable for situations that require a low-noise environment.
Simple construction: easy to produce and maintain.
shortcoming
High cost: The manufacturing process requires the use of expensive permanent magnet materials, resulting in relatively high manufacturing costs.
Performance limitations: In certain specific scenarios, such as high power output and high-speed operation, the performance of permanent magnet synchronous motors may not be as good as asynchronous motors.
DC motor
advantage
Good torque characteristics: The relationship between speed and torque is simple and clear, making it easy to achieve speed regulation and load balancing.
Easy to start and reverse: It has good ability to start and reverse, and can accelerate from a stationary state to a set speed in a very short time.
Easy to control: Its output torque and speed can be controlled through current control, achieving precise control.
Efficient and energy-saving: It is an efficient electric motor with features such as high efficiency, low power consumption, low noise, and low vibration.
shortcoming
Short lifespan of electric brushes: When using electric brushes for power supply, the wear of the brushes is severe, resulting in a short lifespan.
High maintenance costs: The complex structure and wear of electric brushes result in high repair and replacement costs.
Electromagnetic interference: Significant electromagnetic interference is generated during operation, which may have a negative impact on surrounding electronic devices.
Need for DC power supply: A separate DC power supply is required, which increases the cost and difficulty of use.
servo motor
advantage
High precision: It realizes a closed-loop control system for position, speed, and torque, with high precision and high response speed.
Good speed regulation performance: It has good speed regulation performance and can adapt to changes in speed and load.
Strong adaptability: able to withstand loads up to three times the rated value, especially suitable for situations with instantaneous load fluctuations and specified rapid start-up.
Smooth operation: When running at low speeds, it is not easy to cause operating conditions similar to stepper motors, making it suitable for situations with high speed response requirements.
shortcoming
High cost: Due to its high precision and performance requirements, the manufacturing and maintenance costs are relatively high.
There are requirements for the usage environment: although it can be used in places that will be eroded by water or droplets, it cannot be completely moisture-proof or oil proof, and special attention should be paid to the usage environment.
In summary, different types of starting motors have different advantages and disadvantages on excavators. When choosing, it is necessary to comprehensively consider factors such as the specific usage scenario, performance requirements, and cost budget of the excavator.
