Electric motors are limited by the heat they generate. Having a properly sized motor for a specific use is essential to prevent overheating, which could cause damage to the motor or decrease its performance.
Different motor designs were created to dissipate the heat, with different levels of effectiveness.
The most efficient design to dissipate the heat of a motor is the liquid-cooled design. Cooling efficiency is maintained even at lower speeds, which is ideal for constant torque applications.
Combining water and electricity might seem like a bad idea, but it has clear advantages compared to other models. Water cooling can improve the power production capacity of a permanent magnet motor, thus allowing for a smaller-sized motor while being completely safe for users.
Liquid-cooled motors carry a range of benefits over air-cooled types due to better heat dissipation. Nonetheless, they are usually more expensive than air-cooled motors. Therefore, choosing between an air-cooled and a liquid-cooled motor depends on the application.
We’ve identified five situations where liquid-cooled motors are the preferred option compared to non-liquid ones. Let's review them.
When the ambient temperature is high, air-cooled and fan-cooled electric motors can no longer achieve optimal output because the air can no longer absorb the heat sufficiently. Because the effectiveness of water cooling is not contingent on the ambient temperature, liquid-cooled motors do not suffer from performance loss.
Air-cooled motors can suffer from performance issues in dirtier environments such as construction sites. Due to the dust found in those environments, the cooling performance of these motors degrades. Liquid-cooled motors do not suffer the same fate, as they do not dissipate heat the same way.
Liquid-cooled motors are well known for their adaptability compared to standard air-cooled motors, as they offer higher power capacity for the same frame size.
If you are limited in space but need to achieve high power, a liquid-cooled motor is a viable solution. Moreover, liquid-cooled electric motors can be installed close to other components, as there is no overheating risk.
Liquid cooled motors have been designed to optimize energy efficiency and they are also perfectly suitable for variable.
Thanks to liquid cooling, electric motor power can get up to 50% higher than with other cooling methods. This means that liquid-cooled electric motors can be made smaller and also leave a smaller ecological footprint.
Let's now analyze and compare the air-cooled and liquid-cooled versions of the same electric motor model (SMAC 200-052):
Here highlighted in blue the liquid cooling inlets which allows the circulation of the liquid in order to cool the engine
As shown in the above table, a liquid-cooled motor will maintain the same length and the same weight as an air-cooled motor. However, electric motor power will pass from 7.5 kW S2 60 (short-time duty) to 8.0 kW S1 (continuous duty). Efficiency will also improve with the liquid cooling system.
A wide range of liquid-cooled motors are available at e-comer, with low-to-high voltage and IEC, NEMA or SAE interfaces.
Liquid-cooled motors are the right fit in situations where the motor cannot be cooled properly due to external environmental factors like high ambient temperature or dust.
Their use is also relevant when requiring high power density within a limited space.
Many applications require smaller and lighter motors with higher torque density. Since motors have thermal limits, the main challenge in reducing their size is better cooling. Smaller-sized liquid-cooled motors can reach the same torque level as bigger motors without sacrificing performance and efficiency.
If you still wonder what type of motors you should use for your machine, do not hesitate to contact us.
Our team will be pleased to analyze your needs and determine the most optimized electric system for your machine.
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The Canimex Mechanical and Electrical Division is your preferred 360° electrification system integrator in North America. We specialize in integrating and optimizing power transmissions for off-highway applications.
We have experience in electrifying equipment in many markets, including e-mobility, municipalities, material handling, agricultural, construction, marine and many more.
Our solutions include e-axles, e-wheel drives, AC and DC motors, motor controllers, batteries, and many other mechanical & electrical accessories. We make the electrification process easy to help you bring all your projects to life!
