REXRTOH VT-HPC Digital Pump Control

REXRTOH VT-HPC Digital Control Electronic Equipment: The Intelligent Core of Modern Hydraulic Pump Control Systems

In high-performance hydraulic transmission systems, the variable displacement piston pump, as the power source, directly determines the performance upper limit of the entire system in terms of control accuracy, dynamic response, and energy efficiency level. The traditional simulation control method is no longer able to meet the needs of modern industrial equipment in terms of flexibility, integrability, and intelligence. The VT-HPC (Hydraulic Pump Control) digital control electronic device launched by Bosch Rexroth is a revolutionary product designed to address this challenge. It is designed specifically for the A4VS series axial piston pump (with HS5 adjustment mechanism), deeply integrating a digital intelligent control core with powerful network communication capabilities, providing a standardized and high-performance solution for system integration from single pump control to complex hydraulic power units.

Product positioning and core features: the culmination of digital pump control

VT-HPC is not a simple driver or amplifier, but a highly integrated digital control system. Its core mission is to achieve closed-loop control of the displacement angle (inclined plate angle) and output pressure of the variable displacement pump, and integrate torque limiting function to achieve power management of the pump.

Its eye-catching core features include:

Fully digital control: using digital signal processing and advanced control algorithms to replace traditional analog circuits, achieving higher control accuracy, stability, and repeatability.

Open multi bus integration: The device comes standard with support for mainstream industrial real-time Ethernet protocols such as Sercos III, PROFINET RT, EtherCAT, EtherNet/IP, POWERLINK, and can also choose PROFIBUS DP. Switching between bus slave mode and service interface (TCP/IP) can be easily integrated into any automation architecture through parameters.

Scalable software features: Standard features include pressure and displacement angle control. By selecting different software licenses and SD cards, the variable frequency speed control function (HSS), PLC function based on IEC 61131-3 standard, and even advanced applications such as master/slave control and drag function can be activated.

Comprehensive monitoring and diagnosis: Built in comprehensive fault detection mechanism, including power undervoltage, communication errors, analog sensor cable breakage, output short circuit, and internal electronic component temperature monitoring, to ensure the reliable operation of the system.

Compliant with strict standards: The product bears the CE mark, complies with the EMC Directive 2004/108/EC, and meets the electromagnetic compatibility requirements of industrial environments.

Working principle and system architecture: precise control of hydraulic power

The core object of VT-HPC controlling A4VS pump is the electrically controlled proportional valve on the pump. The proportional valve drives the regulating piston of the pump, thereby changing the angle of the inclined plate. The core of the entire closed-loop control lies in two key feedbacks:

Displacement angle feedback: Measure the actual position of the inclined plate through a swing angle sensor.

Pressure feedback: Measure the output pressure of the pump through a pressure sensor.

The controller software of VT-HPC receives real-time set values from the upper system (via bus or analog input) and the actual feedback values mentioned above. After high-performance pressure controller and displacement angle controller calculations, it outputs control signals to drive the proportional valve. Its uniqueness lies in a minimum value selector, which ensures that at any working point, the most "urgent" controller (such as the pressure controller taking priority when reaching the pressure setting) always dominates, thereby achieving smooth control and seamless switching between pressure and flow. The actual torque value is calculated from real-time pressure and displacement angle to achieve precise torque limitation.

Deep Analysis of Hardware and Interfaces: Born for Industrial Connectivity

The hardware design of VT-HPC reflects a high degree of integration and connectivity flexibility.

1. Electrical specifications and power supply:

Working voltage: 24 VDC (range 20-28 VDC), please pay attention to the maximum allowable ripple.

Power consumption: No load current 0.2-0.4A, maximum load current 0.9-2.6A, requires external configuration of 4A delay fuse for protection.

Power loss: less than 15W (at 24V).

2. Core control performance:

Scanning cycle: The minimum scanning time of the displacement angle/pressure controller is only 0.5 milliseconds, providing a foundation for high dynamic hydraulic systems.

Start time: Less than 15 seconds from power on to control system readiness.

3. Rich I/O interfaces (provided through connectors XG20/XG21):

Digital input (4 channels): used for external commands, enable signals, etc., high level 11V-UB, each channel consumes 2-15mA of current.