Which expert can give me some scientific knowledge?

LB_YJY

Which expert can give me some scientific knowledge? [Copy link]

 

Hello everyone: I want to DIY a flying machine, powered by lithium batteries, and I am stuck in choosing a motor. I searched on Baidu and found that they all talk about the basic principles of motors, but what I want to know most is the motor efficiency itself. For example, under the same conditions, what are the efficiency, weight, and torque? Assuming the speed is 2000 rpm, and mechanical transmission loss and driver board loss are not considered at room temperature, which motor has the highest work efficiency at the same voltage and current? The motors currently selected are stepper motors, brushless DC motors, and brushed DC motors. Please help!

maychang

Stepper motors can be ruled out. Stepper motors are not very efficient, and the drive is complex, so the drive will have a lot of losses.

qwqwqw2088

Search on Baidu, all the knowledge is fragmented, systematic learning, find a book to read

ddlxiaoxu

You can see that many quadcopters use brushless DC. There are also brushed DC motors, such as toy helicopters, and hollow cup DC motors, which have low power.   

chunyang

Efficiency is not the most important indicator here. Instead, the relationship between weight and output torque within the budget should be considered. The goal is to achieve greater output torque at the lightest possible weight. The motor type should be selected comprehensively within the range of brushless and brushed.

LB_YJY

maychang posted on 2019-1-10 09:31 Stepper motors can be ruled out. The efficiency of stepper motors is not high, and the drive is complex, so the drive will have a lot of losses.

Thank you! I also learned this from the TI official website.

LB_YJY

qwqwqw2088 posted on 2019-1-10 10:18 Search on Baidu, it’s all fragmented knowledge. Find a book to read carefully for systematic learning

Thank you!

LB_YJY

ddlxiaoxu posted on 2019-1-10 11:01 You can see that many quadcopters use brushless DC. There are also brushed DC ones, such as toy helicopters, and those with hollow cups...

Thank you! It seems that I have to use brushless motors. The EMI of BDC is more difficult to deal with, and it interferes with my analog circuits!

LB_YJY

chunyang posted on 2019-1-10 11:37 Efficiency is not the most important indicator here, but the relationship between weight and output torque within the budget should be considered, and the pursuit of the lightest weight possible...

chunyang Correct answer! Thank you! Can you recommend a few motor models? The weight, efficiency and torque indicators are relatively good! The diameter is controlled within 15mm, and the price is excluded first.

chunyang

LB_YJY published on 2019-1-10 20:57 Chunyang correct answer! Thank you! Can you recommend a few motor models? Weight, efficiency, torque indicators are relatively good! The diameter is controlled within 15mm, the price...

You need to choose this by yourself, according to the takeoff weight of the whole aircraft and leave an appropriate margin to choose. Within the acceptable range, choose a large one first, because under the same technical conditions, a large one usually has a high torque. Another thing is to pay attention to the magnetic material. The torque of the NdFeB magnet is usually high. If you don’t care about the price and pursue the ultimate performance, then the Nissan micro motor is preferred. If you pursue cost-effectiveness, consider the products of domestic miscellaneous brands. The price difference between the two categories can reach different orders of magnitude.

LB_YJY

chunyang posted on 2019-1-11 11:52 You need to choose it yourself, according to the takeoff weight of the whole aircraft and leave an appropriate margin. Within the acceptable range, choose a larger one first, because the same technology...

Thank you! I learned a lot!