Controller for electric power steering
13 March 2019
The new Curtis Model 1220E brushed DC permanent magnet motor controller for electric power steering and steer-by-wire systems fully meets EN1175 1:1998+A1: 2010 standards.
This controller is exclusively designed for Curtis Vehicle Control Language (VCL) enabled AC-traction controllers. The steering motor functions as an actuator to change the angle of the wheels thereby changing travel direction. Model 1220E interprets the steering command input and wheel position feedback, to steer the vehicle. Intended applications are class-3 material handling vehicles such as pallet trucks, stackers and similar industrial vehicles.
The controller features absolute and relative position control modes. Model 1220 e has 20 kHz Pulse Width Modulation (PWM) switching frequency to ensure silent operation. Advanced PWM techniques produce low motor harmonics, low torque ripple, and minimised heating losses, resulting in high efficiency. Powerful features include configurable homing methods, centre offset, and end-stop protection. Model 1220e, with CANopen system communication, operates with 24V and 36/48V nominal supply voltage and 60A 1-minute current rating. Hour meter and diagnostic log functions are integrated.
The Curtis 840 Spyglass can be connected to show traction and steering information such as BDI, hour meter, fault, traction speed, and steered wheel angle. Model 1220 e is designed for maximum safety with dual redundant configuration of all safety relevant parts. Fault output can be used to turn off traction controller’s main contactor and EM Brake. The new controller provides Separate input paths to each micro for all input and feedback signals. Following error check ensures the wheel position tracks the steering command.
Model 1220e meets or complies with relevant US and international regulations:
• EMC: Designed to the requirements of EN12895:2015.
• EN1175- 1:1998+A1:2010.
• UL recognised per UL583.
• Designed to the EN13849 standard achieving a PL=d, Category 3 for all Safety Functions.
• Electronics sealed to IPX4.