VT-VSPD-1-23/V0/0-0-1 REXROTH closed-loop control electronics

5.1 Performance description

The closed-loop control electronics VT-VPCD is part of a control system for the electrohydraulic control of swivel angle and pressure and power limitation of axial piston pumps of type A4VS… with HS4 control as well as axial piston pumps of type A2V… with EO4 control, each fitted with a proportional valve and swivel angle and position transducers for sensing the swivel angle and the valve spool travel. The control electronics VT-VPCD provides all electrical functions required for the control types HS4 and EO4. The control electronics VT-VPCD can be configured using the software BODAC.

5.2 Product description

The figures given in brackets refer to the block circuit diagrams in Chapter 5.2.2 “Block circuit diagrams“ from page 20 on.

The operating principle of the complete system is explained in data sheet RE 30028.

The digital control electronics VT-VPCD consists of a swivel angle controller, a pressure controller and a valve controller as well as of a power limiter. The position of the pump‘s swashplate is sensed by an inductive swivel angle transducer, the actual pressure value is sensed by a pressure transducer. Both actual values are fed to the control electronics and linked to each other by software. The actual power value is formed by the product of actual pressure value and actual swivel angle value.

The controller software ensures with the help of a minimum value comparator that only the controller is active, which is assigned to the relevant working point.

The control electronics is designed as double-sided printed-circuit board in Euro card format 100 x 160 mm. It comprises a switched-mode power supply unit [1], which generates all the internally required voltages.

The central unit is a micro-controller, which controls the entire sequence and realizes the functions of the controller. Configuration data, command values and parameters are saved in a non-volatile FLASH.

VT-VSPD-1-23/V0/0-0-1