Elevator motor

A typical elevator motor consists of several primary components, which interact to generate the driving force needed to move the elevator:

• Fixed stator: The stator is usually a laminated pack with windings that generates an electromagnetic field of rotation when electrical current is added.
   
• Moving rotor: The rotor is the rotating part of the electric motor. 
  In the rotor of elevator motors designed as permanent magnet excited synchronousmotors, permanent magnets are arranged with alternating poles. The rotational speed is synchronous with the electrical frequency of the stator field. 
  In the case of asynchronous motors, the rotational speed deviates asynchronously from the electrical frequency because the rotor's magnetic field has to respond to the energisation of the stator, meaning that the rotor follows with a delay (slip). The rotor therefore also has windings instead of magnets. The rotor winding is usually a short-circuited winding made of copper or aluminium rods. 
  Depending on the design, the rotor can be mounted inside the stator (internal rotor) or outside and around the stator (external rotor).
   
• Housing: The electrical junction box is located in the housing.

Fundamentally, all rotating electric motors consist of a fixed, non-moving stator and the rotating rotor. 

If a three-phase winding is energised with alternating current, it generates an electromagnetic field of rotation. In between the stator and the rotor, there is a narrow air gap, which forms the interaction surface between the electromagnetic field of rotation and the permanent magnets or the rotor winding. In physical terms, different pole pairs attract one another while identical polepairs simultaneously reject one another. The stator field rotates in the air gap and pulls along the corresponding rotor magnet poles.

Elevator motors designed with external rotors have a significantly larger magnetic interaction area than those with internal rotors and can therefore generally achieve a higher torque in the same volume. Internal rotors, on the other hand, allows for particularly narrow and long designs that are better suited for installation in an elevator shaft.

Regardless of their operating principle, elevator motors can be designed as synchronous or asynchronous motors both on gearboxes and without gearboxes. 
Gearless technology is usually installed in modern elevator systems, as it is particularly low-maintenance, efficient and quiet in operation. At the same time, these designs offer particular benefits for installation in the elevator shaft. 
Since the majority of elevators are installed without a machine room (power pack room), gearless drives have now almost completely replaced elevator motors with gearboxes.

To make sure that the selected system always meets the desired requirements, marks of quality for drive systems include:

• Efficiency: High-quality elevator motors are designed to achieve high energy efficiency, resulting in lower energy consumption and thus lower operating costs. As a positive side effect, resources are saved, which contributes to sustainability.
   
• Precise torque control: To achieve the most efficient level of operation possible with the lowest possible vibration behaviour, the electromagnetic circuit between the stator and rotor must be carefully optimised.
   
• Low-noise operation: To increase passenger comfort and reduce the overall noise level in buildings, high-quality elevator motors are specially designed for low-noise operation.
   
• Reliability: To minimise downtime and ensure the highest level of safety at all times, reliable operation is immensely important. Gearless elevator motors in particular require no maintenance. Only attachments such as traction sheaves and the brake system need to be serviced.
   
• Compatibility and flexibility: High-quality elevator motors or drive systems for elevators can be expanded in a number of ways and used in a variety of applications. For instance, connectivity to cloud-based monitoring platforms allows for real-time analysis, monitoring of sensor data or predictive maintenance notifications.

» Real-time monitoring any time, any place: ZAbluegalaxy for drive technology

In general, the selection of a suitable elevator motor or drive system always depends on the specific requirements of the application, such as load capacity, speed, energy efficiency or sound characteristics, and the existing installation situation (e.g. space restrictions, systems with or without control cabinet, etc.). 

Specially developed design software for elevator machine systems is an essential tool for selecting the ideal combination of elevator machine, frequency inverter and other components for the application situation. 

In all cases, we advise consulting qualified specialist personnel to clarify the individual requirements and find the best possible technical solution.

​» Designing your ideal elevator: ZAlift design software from ZIEHL-ABEGG

An effective elevator retrofit programme gives operators the opportunity to upgrade existing systems and improve their performance, safety and efficiency. 

The upgrade concept should be individually developed for the particular use case and existing installation conditions. 

Retrofit programmes usually include a professional inventory analysis, the selection of suitable components, their installation and startup, as well as training on how to use the new system.

» Increase the efficiency of your elevator system with RETROFITBLUE from ZIEHL-ABEGG