Can the stepper motor replace the servo drive successfully? The answer may seem obvious: "No". Stepper motor will not meet the requirements of applications with high dynamics, will lose steps, will not give us information about its position. Most stepper drives acts like that. Not everyone is yet aware that there are solutions operating like a hybrid of a stepper motor and servo motor. In some areas they are an excellent alternative to popular servos.
A few words about classic stepper drives
The design of traditional steppers is very simple, apart from the motor they do not consist of an encoder, controller or driver, they do not have a closed loop, they consume a lot of energy, because they always work with maximum power. This makes classic stepper motors work best in applications that do not require high velocity and high accelerations, often in simple CNC machines and when working on setting axes. The biggest advantage of these solutions is their low price. However, apart from the low cost of production and purchase, the old generation stepper motors cannot withstand the competition with servo motors.
Among specialists of the machine-building industry, sometimes there is a conviction that the servo will always be better than the stepper motor. As a result, projects tend to be “oversized” – the parameters exceeds the needs.
Remedy for the disadvantages of stepper motors
A few years ago, the stereotype about the superiority of servos over steppers was overthrown by the Danish company JVL – a manufacturer of both stepper motors and servo motors. They decided to develop a hi-tech, integrated solution that combines the features of both types of motors, while still being affordable.
The result is a series of ServoStep integrated stepper motors that JVL started to sell two years ago. The ServoStep is still conquering the market. It is particularly appreciated by designers, integrators and end users of machines who value innovation, simplicity of assembly, control and use.
ServoStep Series – what makes it stand apart?
JVL ServoStep motors are drives consisting of a stepper motor, a hallsensor, electronics and an encoder that together form an enclosed, compact unit. The driver and controller are also mounted inside the motor in a closed section. The JVL integrated stepper motors can be delivered in torque range of 0.36 to 25 Nm and a flange size from 43 mm to 110 mm. They are characterized by very high resolution – up to 409,600 steps per revolution. It is a cost-effective alternative to servo drives, in applications where very high work dynamics is not required.
The choice of ServoStep motors also means much better protection against electrical noises due to the lack of any cables between the motor and the controller.
Interestingly, that the safety function STO (Safety Torque Off), typical for servo drives, is also an option in ServoStep motors.
In addition, the innovative JVL stepper motors cooperate with all available interfaces, and thanks to the built-in nanoPLC, you can download any logic to them. The switch, on the other hand, allows direct connection between motors.
More about the ServoStep integrated stepper motors under Products and on the manufacturer’s website: