By
As an important power device, motors are widely used in industrial production, transportation, household appliances, and other fields. Under certain conditions, motors may face the problem of not being able to operate normally, which has an important impact on work efficiency and equipment reliability. Understanding the impact of these constraints on motor performance, and taking appropriate measures to counteract them, is critical to ensuring reliable motor operation.
Effects of high altitude on motors
Unduly altitude is one of the common limiting factors that can affect the proper operation of a motor. As the altitude increases, the atmospheric pressure as well as the oxygen level in the air decreases. This will directly affect the dissipation of heat and the cooling effect of the motor. This is because, in a low oxygen environment, the efficiencies of both the fan and the cooler inside the motor are reduced, which culminates in higher temperatures inside the motor. Besides that, motors are also typically exposed to higher ambient temperatures compared to lower altitudes, which further aggravates the problem of difficult heat dissipation.
Constrained by atmospheric pressure and oxygen levels, the motors cannot dissipate the heat through natural cooling. In other words, the motor requires a more powerful cooling system to maintain a normal temperature. Otherwise, an overheated motor will cause damage or shutdown to the equipment.
Starting and operating motors may be problematic for starting and running at high altitudes. Because the air is thin, oxygen inside the motor is poorly served, which negatively affects its combustion efficiency. This makes it impossible for the motor either to start or to operate erratically. The amount of load carried by a motor at high altitude is lower, which also affects operating efficiency.
Solutions that can be employed to work in conformity with constraints imposed by high altitude are as follows:
Adopt a better heat dissipation system: With the heat-dissipating effects of motors in high altitudes, improved heat-dissipation systems can be used, which include increased fans or the use of a liquid cooling mechanism.
Increase motor power accordingly: usually, because of the thin air, the output power of the motor is reduced; one can increase the power of the motor appropriately to try and make it up to enable the motor to operate normally.
Optimize the system of motor control: within high-altitude areas, by optimizing the motor control system, the accuracy and reaction speed of the motor can be improved toward improving the starting and operation performance of the motor.
Effects of low temperature on motors
Low temperatures are one of the ordinary limiting factors the motors have to stand under specific environments. Under low temperatures, the inner mechanical parts within the motor, like the bearings or gears, tend to get worn and deformed easily. All these are major because of the reason that these mechanical parts turn fragile, and become brittle, thereby decreasing the load-carrying capabilities of the same parts.
When the temperature of the working environment is too low, the lubricating oil inside the motor will get sticky, which causes loss of its lubricating effect and protecting action. Therefore, internal parts may produce friction and wear, affect the normal operation of motors, and increase the burden at the startup of motors. Furthermore, with a drop in temperature, the current utilized by the motor increases, hence an increase in energy consumption by the motor.
To avoid further deteriorating the impact of low temperatures on motor operation, the following can be implemented:
Adopt high-quality lubricant: In a low-temperature environment, the lubricant inside the motor is easily broken. Using a high-quality lubricant will reduce friction and wear, thus protecting the normal operation and life of mechanical parts.
Keep the temperature of the motor stable: During work in a low-temperature environment, the temperature of the motor will affect the normal operation of the motor. Using heating-up equipment and insulation materials, etc., the temperature of the motor can be kept stable to avoid overcooling of the motor and affecting the normal operation of the motor.
Ensure that the motor is sufficiently preheated: If working in a low-temperature environment, then the motor should be allowed to preheat adequately to ensure that the burden during start-up is less and, hence, enhances the starting success rate. The actual preheating time, which depends on the given circumstances, shall not be less than 30 minutes in an alow-temperaturee environment.
Effects of light load on the motors
Light load refers to when the operation of the motor is subjected to a little load and operates under a light load. Though the light load might not have a massive adverse effect on the motor, it prohibits the engine from operating at an optimum condition.
When the motor is operating under light load conditions, its output power is relatively low, and the fixed losses of the motor itself, such as iron loss and copper loss, are related to the rated power of the motor. Thus, the efficiency of the motor decreases under light load conditions. That is to say, it needs to consume more power to accomplish the same task, thus increasing the waste of energy.
Under light loads, output power is low, meaning the speed of rotor motion is low, hence leading to a lower rate of change of the magnetic field. Eddy currents are those induced currents inside metal parts due to changes in the magnetic field, consuming a part of electrical energy and heating up. Therefore, eddy current losses of a motor increase under light load conditions.
Following are a few measures that we may consider to overcome the influence of light load on motors:
Speed adjustment of the motor by using a frequency converter: a frequency converter may be used to adjust the motor speed based on actual load demand to make the motor work under a better load condition, which may improve efficiency and energy saving for the motor.
Regular check and maintenance: It is necessary to constantly observe the operating condition and temperature of the motor to keep the motor running normally. Ensuring that insulation and ventilation are in good condition can decrease the motor temperature and reduce losses.
Run in parallel or use multiple motors: If the load varies over a large range, consider running multiple motors in parallel to maintain the motors in a much higher load range. That can improve overall efficiency and reduce problems at light loads.
Conclusion
These limiting factors have to be learned so that necessary measures can be taken for the proper and reliable operation of motors. It is only by learning the impact of these constraints on motor performance that one can take appropriate measures for the reliable operation of motors and improve their efficiency and life span, thus satisfying practical needs.
