What are AC and DC Servo Motors? Their Features and Differences

Servo motors are divided into two categories: AC servo motors and DC servo motors. In this week’s blog post, we will discuss AC servo motors and DC servo motors. Throughout the article, we will answer questions such as “What is an AC servo motor?” and “What is a DC servo motor?” After presenting the features of AC servo motors and DC servo motors, we will list the differences between AC and DC servo motors. Additionally, we will provide guidance on the prices of AC and DC servo motors. We hope you find this article useful and wish you a pleasant read.

What is an AC Servo Motor?

AC servo motors, also known as brushed servo motors, are a type of servo motor that is preferred in projects requiring high power and frequency values. The most distinctive feature of AC servo motors, i.e., brushed servo motors, is that the magnetic field remains stationary while the coils move. AC servo motors are widely used in industrial automation and robotic systems, providing precise position, speed, and torque control. These motors use feedback devices (usually encoders or resolvers) to adjust the correct current and voltage to reach the desired position, speed, or torque. They are preferred in applications that require high precision, efficiency, and dynamic performance. They provide position, speed, and torque control in applications requiring high precision, respond quickly to sudden load changes, offer high energy efficiency, and monitor and optimize motor performance through feedback systems. They can operate across a wide range of speeds and torques for various applications and are commonly used in automation systems requiring high precision, such as CNC machines, robotic arms, and automated assembly lines.

Key Features of AC Servo Motors

The main features of AC servo motors (brushed) are as follows:

• AC servo motors are preferred in projects requiring high power and frequency values.
• AC servo motors with high-energy magnetic fields offer significant advantages in terms of efficiency in the areas where they are used.
• It enables fast and sequential positioning in applications requiring motion control.
• AC servo motors, a type of high-speed motor, continue to operate without compromising their stability even under demanding working conditions.
• AC servo motors are classified as induction motors.
• AC induction motors are manufactured in two-phase and three-phase versions.

Advantages of AC Servo Motors

The main advantages offered by brushed servo motors are as follows:

• Ensures high reliability
• Low maintenance requirements
• No electrical contacts while in motion

Disadvantages of AC Servo Motors

The main disadvantages of brushed servo motors are as follows:

• Low efficiency
• High heat dissipation and the resulting need for a fan motor
• Requirement for a square wave AC power supply

AC Servo Motor Prices

In AC servo motors, which provide high efficiency in terms of sensitivity, the lower the amount of rotation angle, the higher the sensitivity. AC servo motor prices also vary depending on the technical specifications of the motor. The servo motor and its driver should be determined according to the energy required by the project where the (brushed) AC servo motor will be applied.
We have briefly outlined the benefits that AC servo motors provide in terms of precision and power. You can select the type that suits your needs in terms of AC servo motor prices and specifications and use them in your applications.

What is a DC Servo Motor? What are its Features?

Also known as a brushless servo motor, the DC servo motor is a type of motor used in systems requiring high power, speed, and torque. It converts electrical energy into mechanical energy, enabling the system to operate. The most significant difference between it and AC servo motor types is that it is a brushless motor type.

DC Servo Motor Types

Brushless DC servo motors are divided into different types:

• Brush DC motor
• Brushless DC motor
• Shunt DC motor
• Series DC motor
• Compound DC motor

DC Servo Motor Advantages

The main advantages offered by brushless DC servo motor types are as follows:

• Brush and commutator elements are present and require minimal maintenance.
• They consume less energy.
• The motor shaft diameter is longer compared to standard motors.
• Friction that may occur during operation does not occur in brushless DC servo motors.

DC Servo Motor Disadvantages

The disadvantages of brushless DC servo motor types are as follows:

• Requires regular maintenance of the commutator.
• The bristle version cannot be used in clean areas due to dust generated by friction.
• Inability to achieve high speed and torque due to its commutator structure.

Things to Consider When Choosing a DC Servo Motor

Those wishing to purchase a DC servo motor should consider the following characteristics of the motor they wish to purchase:

• Motor shaft rotation speed
• Terminal voltage ratio
• Continuous current level
• Continuous torque level
• Continuous output power level

Key Features of DC Servo Motors

The main features of brushless DC servo motors can be listed as follows:

• It can reach high torque values for short periods. This increases operational efficiency.
• It can generate high energy even at low speeds.
• During operation, the coils remain stationary and the magnetic field is in motion.
• It has a feedback system.
• Brushless DC servo motors automatically perform control and fault repair operations.
• DC servo motors are commonly used in X-ray machines, automatic doors, fans, air conditioners, and similar applications.
• DC motors that operate with PWM can be analog or digital.
• DC motors are longer than standard electronic motors.

DC Servo Motor Prices

Brushless DC servo motor prices vary depending on the technical specifications of the motor. The main technical specifications that determine the price include the motor’s power, torque, speed, and flange size. Choosing the appropriate DC motor for the application will prevent problems in the systems where the motor will operate.
We have reached the end of our blog post on brushless DC servo motors. You can access detailed information about DC servo motor prices and types through the Şahin Rulman website, which sells mechanical and electronic products online, and place an order after learning about DC servo motor prices.

AC Servo Motor – DC Servo Motor Comparison

AC servo motors are known as brushless DC servo motors. In systems using servo motors, if you are using a DC servo motor, you will need to check its brushes in case of malfunctions. This is because the brushes become dirty during operation and cause problems over time. As usage time increases, the efficiency of the servo motor will decrease proportionally due to this dirtiness. One of the biggest contributions of AC servo motors to projects where they are used is that they are brushless. We can say that AC servo motors are preferred more because they do not require much maintenance.
During servo motor operation, the brushes create friction. This directly affects the efficiency obtained from the operation. Since AC servo motors are brushless, they offer a better frictionless environment compared to DC servo motors. DC servo motors are longer than AC servo motors due to their brushes and collectors. AC servo motors can be used in projects requiring both high and low power, while DC servo motors are used in applications requiring high power. AC servo motors are preferred more often because they can meet both needs.
Servomaster servo motors, manufactured by Şahin Rulman, are produced as AC servo motors. Servomaster servo motor prices vary depending on the technical specifications of the motor, such as torque and moment. You can purchase the servo motor with the power suitable for your project online from the Şahin Rulman website.