How to Reduce Inefficiency in Motors

Inefficiency is a constant issue in mechatronics and the wider motion control industry with companies continually striving to improve on it year after year. There are still a few important steps that can be taken to help make your setup as efficient as it can be…

1. Choose the right motor and controller

It might sound obvious but component selection is arguably the most important factor in determining the overall efficiency of the system. In the same way that if you select and amplifier that is not powerful enough to drive your speakers it will get hot and eventually blow, so too with motors. Make sure you’re always looking at running or nominal power and try and get something that has plenty of ‘headroom’ for your application. If not you run the risk of placing excessive load on the motor. Excessive load can start to damage bearings, causes excess heat within the motor coils (don’t forget that when it comes to motors, wherever there is heat there is wasted energy). Therefore, choose a motor that has what it takes to deliver the torque and speed you need with ease.

Likewise with the controller – ensure you have plenty of headroom wherever possible. One of the biggest enemies of electronics is heat. Place too much load on a controller and it will start to get hot. Where there is heat, there is inefficiency and reduced life. As parts wear and are further damaged then the controller will not function as well as it could do. If you’re not sure on any of these factors you can always give us a call, we’re happy to go through any of these issues or help you make the right decision.

2. Only use a gearbox if you absolutely have to

Gearboxes are typically 75% efficient so adding a gearbox to a motor is going to significantly reduce the overall efficiency of the system. There are obviously some applications in which a gearbox is the only way that you can deliver the required mechanical performance but if possible you should avoid adding a gearbox.

3. Choose the best possible quality of component

Lower quality motors means lower quality bearings and build quality. Lower quality bearings and build quality means more friction. More friction means more inefficiency. Choose the best possible motors you can within your budget and this can make a big difference in delivering the most efficient outcome for your project.

4. Think carefully about the type of motor you use

There are applications where motor type is pretty much already decided by the key requirements of the project. If this is you then ignore this point. However, in other cases there are applications where there may be a number of different options. Brushed DC is often lower cost but a brushless DC motor will not only be more efficient but it will also last 5-10 times longer on average than the brushed DC alternative. Similarly with stepper motors – it may be that a brushless DC system could deliver the performance you need at significantly increased efficiency.

5. Lots to think about

As you can probably see from this very simple introduction to the subject, there is a lot to think about when considering efficiency in motors and controllers. For more detail on efficiency in motors, controllers and gearboxes you can read more here. Alternatively, if you have a specific project that you’re working on now and would like to discuss some of your options with us then please contact us here and we’d be happy to help.