Brushed motors use carbon brushes for commutation, offering simplicity but lower efficiency (75-80%) and shorter lifespans (~1,000-3,000 hours). Brushless motors use electronic controllers, achieving higher efficiency (85-90%), longer lifespans (10,000+ hours).
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The average lifespan of brushed motors ranges from 1,000 to 5,000 hours, while brushless motors can operate for 10,000 to 50,000 hours, making brushless motors 2 to 10 times more durable than their brushed counterparts. Brushed motors require frequent maintenance, with brushes needing replacement every 500 hours, whereas brushless motors extend their maintenance intervals to over 5,000 hours.
A factory reported five instances of downtime in one year due to brush replacements in brushed motors. After switching to brushless motors, downtime decreased to one instance, boosting production efficiency and reducing annual idle losses by 12%. Brushless motors typically operate with an efficiency of 85% to 90%, compared to 70% to 75% for brushed motors.
For a 1,000-watt motor running continuously for 1,000 hours, a brushless motor saves approximately 150 kWh of energy compared to a brushed motor. The lifespan of a brushed motor is about 3 to 5 years, while brushless motors reliably last 8 to 10 years. Products using brushless motors have a return rate of less than 5%, whereas products with brushed motors experience return rates as high as 15%.
Although brushless motors have an initial cost 1.5 to 3 times higher than brushed motors, their total ownership costs are lower. The average annual maintenance cost for a brushed motor is $100, while brushless motors cost only $30 annually for maintenance.
Brushless motors are now used in 65% of industrial equipment, with market demand growing at 8% annually. By 2030, brushless motors are expected to account for over 80% of the global motor market. The average lifespan of brushed motors has decreased by 30%. Electric vehicles equipped with brushless motors can run over 200,000 kilometers, while those with brushed motors typically last less than 100,000 kilometers.
Rotational Speed
The rotational speed of brushed motors is generally limited to 3,000 to 5,000 RPM (revolutions per minute). In contrast, brushless motors are designed to easily reach speeds of 10,000 to 100,000 RPM.
A 1,000-watt brushed motor operating at 3,000 RPM achieves an efficiency of approximately 70%, whereas a brushless motor under similar conditions achieves 85% to 90% efficiency at 10,000 RPM. High-speed cutting tools equipped with brushless motors increase cutting speed by 40% while reducing energy consumption by about 15%.
At speeds exceeding 6,000 RPM, the brush temperature in brushed motors rises above 120°C. Brushless motors, with their brushless design, maintain stable operating temperatures below 70°C even at speeds over 10,000 RPM, ensuring reliable long-term performance.
In continuous operation, a brushed motor running at 5,000 RPM has a lifespan of approximately 1,000 hours, while a brushless motor running at 10,000 RPM can operate for over 10,000 hours. This 10-fold difference makes brushless motors more attractive for high-load and high-speed applications.
When load increases by 10%, the rotational speed of brushed motors may drop by 15%, whereas brushless motors typically experience a speed reduction of less than 5%.
Brushed motors produce greater mechanical vibration at high speeds due to friction between brushes and the commutator, with vibration amplitudes reaching up to 0.5 mm. Brushless motors, however, have vibration amplitudes typically below 0.1 mm. A household appliance manufacturer reduced washing machine noise from 72 dB to 58 dB by adopting brushless motors.
Thanks to the electronic commutation in brushless motors, their acceleration response time is typically less than 0.1 seconds, compared to over 0.3 seconds for brushed motors. A race car equipped with a brushless motor accelerates from 0 to 10,000 RPM in just 1.2 seconds, while a brushed motor requires over 3 seconds.
Efficiency
Brushed motors typically operate at an efficiency of 70% to 75%, primarily limited by friction losses between brushes and the commutator. In contrast, brushless motors achieve efficiencies of 85% to 90% or higher. This 10% to 15% efficiency gap significantly reduces energy costs in long-running equipment.
A 1,000-watt device running for 100 hours consumes approximately 130 kWh with a brushed motor but only 110 kWh with a brushless motor, saving 15% energy. Under full load conditions, brushed motors experience heat losses exceeding 20% of input energy, while brushless motors limit heat losses to 5% to 10%.
In electric vehicles, those equipped with brushless motors can typically travel 30% farther per charge compared to vehicles with brushed motors. For instance, a brushed motor-powered electric vehicle might have a range of 100 kilometers per full charge, while switching to a brushless motor extends the range to 130 kilometers.
When the load increases from 50% to 100%, brushed motor efficiency drops by about 12%, whereas brushless motor efficiency decreases by less than 5%. Modern brushless motor controllers have an error rate below 1%, compared to brushed motors, which often exhibit error rates as high as 5% due to mechanical commutation.
Brushed motors generate noise from contact friction between brushes and the commutator, typically ranging from 60 to 70 decibels. In contrast, brushless motors, with their brush-free design, produce noise levels of only 40 to 50 decibels.
The efficiency of brushed motors decreases as brushes wear down, often dropping to 65% after 500 hours of operation. Brushless motors, however, maintain nearly consistent efficiency over 10,000 hours. An industrial equipment manufacturer reported a 25% improvement in overall efficiency and a 60% reduction in maintenance frequency after transitioning to brushless motors.
At ambient temperatures of 40°C, brushed motor efficiency may decrease by more than 10%, whereas brushless motors exhibit less than a 5% decline. Upgrading to brushless motors raised motor efficiency from 72% to 88%, saving approximately $50,000 annually on electricity costs and reducing the payback period by two years.
Noise
Brushed motors generate noise levels of 60 to 70 decibels during operation, whereas brushless motors operate much quieter, typically below 50 decibels. For example, vacuum cleaners with brushless motors produce 15% to 20% less noise than those with brushed motors.
At speeds of 5,000 RPM, brushed motors produce noise exceeding 75 decibels, while brushless motors maintain noise levels below 55 decibels, even at speeds above 10,000 RPM. Production lines relying on brushed motors often require additional soundproofing at a cost of around $50,000. Switching to brushless motors reduces noise levels by 20 decibels, eliminating the need for such measures.
After 500 hours of operation, brushed motor noise levels may increase by 15%. After 1,000 hours, noise levels for brushed motors can rise from 65 decibels to 72 decibels, whereas brushless motor noise remains steady at 50 decibels.
Brushless motors reduce vibrations through precise electronic control, with amplitudes typically below 0.1 millimeters, compared to brushed motors with amplitudes up to 0.3 millimeters. Power tools using brushed motors often exceed noise levels of 80 decibels under full load, while brushless motor tools maintain levels around 65 decibels.
When ambient temperatures rise from 25°C to 40°C, brushed motor noise can increase by 5 decibels, while brushless motors exhibit almost no change. New low-noise brushless motors with coreless designs have noise levels reduced to below 40 decibels. By 2030, low-noise brushless motors are expected to account for more than 75% of the market.
An electric vehicle brand upgraded its drive system to brushless motors, reducing driving noise from 70 decibels to 50 decibels. This improvement directly boosted sales, with an annual growth rate of 12%.
Torque
A standard brushed motor can deliver an initial torque of 2 Nm, but after 500 hours of operation, its output may drop to 1.6 Nm, representing a torque reduction of up to 20%. In contrast, brushless motors consistently provide over 2 Nm of torque, with performance degradation typically less than 5% even after 10,000 hours of operation.
Brushless motor systems can achieve rated torque output within 0.2 seconds, compared to about 0.5 seconds for brushed motors. This difference enhances dynamic performance, reducing vehicle acceleration times by approximately 10%. Brushed motors have a maximum torque efficiency of around 75%, while brushless motors achieve efficiencies exceeding 90%, delivering 20% more usable torque.
When the load increases by 20%, brushed motors often experience a torque drop of 15% to 20%, whereas brushless motors show a decline of less than 5%. On an automated production line, switching to brushless motors improved equipment productivity by 12%.
Brushed motors exhibit torque fluctuations of up to 10%, while brushless motors maintain torque stability with fluctuations typically below 1%. When ambient temperatures rise from 25°C to 40°C, brushed motor torque may decrease by 10%, whereas brushless motors, due to their non-contact design, exhibit torque variations of less than 2%.
A 500-watt brushless motor typically has 30% higher torque density than a brushed motor. Brushed motors, with torque decreasing over time, require carbon brush replacement every 1,000 hours, whereas brushless motors offer greater torque stability, extending maintenance cycles to over 5,000 hours.
Cost
Brushed motors have lower initial costs, typically 50% to 70% of the price of equivalent brushless motors. A 500-watt brushed motor costs approximately $50, while a brushless motor of the same specification costs between $75 and $100.
Brushed motors require periodic brush replacements every 500 to 1,000 hours, with maintenance costs ranging from $30 to $50 per service. Equipment using brushless motors incurs 40% lower average annual maintenance costs compared to brushed motor systems.
Brushed motors typically operate at 70% to 75% efficiency, while brushless motors achieve 85% to 90% efficiency. For a 1,000-watt device running 100 hours, a brushed motor consumes approximately 133 kWh, while a brushless motor consumes only 111 kWh, saving 22 kWh. At an electricity rate of $0.1 per kWh, this translates to $2.2 in energy savings over 100 hours.
Brushed motors have a lifespan of 1,000 to 5,000 hours, whereas brushless motors last 10,000 to 50,000 hours. An industrial company that switched its production line to brushless motors reduced total costs by approximately 30% over 10 years.
An electric vehicle equipped with a brushed motor requires motor replacement every three years, while vehicles with brushless motors can run for 8 to 10 years, saving at least two replacement cycles. With each motor replacement costing $500, using a brushless motor saves over $1,000 in total.
Switching to brushless motors reduces operational waste by approximately 90%. By 2030, the average price of brushless motors is expected to decrease by 20%, further narrowing the cost gap with brushed motors.
A market research firm found that brushless motor adoption in commercial equipment has exceeded 60% and is projected to grow to over 80% within the next five years. Over a five-year lifecycle, the total cost (including purchase, maintenance, and energy consumption) of a brushed motor is approximately $300, compared to $250 for a brushless motor.
