Laboratory power supplies - High performance laboratory power supply from modular system


The PSI 9000 series sets new standards in laboratory power supply: its modular system enables supplies with a power of up to 90 kW to be achieved with only a few modules. A Master-Slave interface and a Shared Bus allow multiple units to be coupled to provide a total system of up to 300kW.

EA Elektro-Automatik has developed a new series of controllable laboratory power supplies which is so versatile that practically any application can be covered. The basis for this is a flexible output stage developed by EA. This enables a significantly larger operational area as the scalability can achieve a much larger voltage and current window enabling one unit to supply a variety of applications – a space and cost saving solution for limited laboratory facilities.

Numerous voltage and current classes
The performance laboratory power supplies in the PSI 9000 range achieve power of 640W up to 90kW, voltage of 40V up to 1500V and current of up to 3060A. Despite this multiplicity the supplies require only a few performance modules. The manufacturer has attained this with a specially developed modular system: components with 640W, 1.5kW and 5kW can be combined in one unit up to 15kW. Thanks to an intelligent Master-Slave interface and a Shared Bus these units can be combined to give a total system of up to 300kW. The system is controlled and selected by a master device with a HMI unit. The slave extension units require no control panel and no further interfaces, thus reducing the total system cost.

Extensive functionality
In addition to an ordinary laboratory power supply the PSI 9000 series is equipped with a functional and arbitrary generator as well as an automobile start up curve to DIN 40839. Thus, sine, triangular, square and other curve forms can be engaged by keystroke and readily programmed. Furthermore, a sequencing and logging function, a battery management system and the simulation of photovoltaic and fuel cells can be incorporated into the power supply. Many other parameters such as time and limit values for voltage, current, power and resistance are freely configurable.

Intuitive operability
Because of the multiplicity of functions the developers have introduced a new, user-friendly operating concept: with the aid of a high definition TFT display with a capacitance touch screen the units can be intuitively operated. The menu is clearly designed and available in German, English, Chinese and Russian. With few key strokes the parameters can be selected and values entered via encoder or number panel.

Simulation of non-linear characteristic curves
The digital regulation and control is based on a 16 Bit AD/DA converter.  Because of the parallel signal processing of the FPGA the elapsed time of a signal - measurement, calculation and adjustment - is less than 1µs. Thus, a band width of 1 MHz can process current, voltage, power and resistance simultaneously. The user allotted look up tables (LUTs) also work with a band width of 1MHz. In this way, alongside standard linear control, complex non-linear characteristic curves can be simulated, such as those of a battery, fuel cell or a photovoltaic facility. The required tables can be generated in Excel or Text and transferred to the LUTs via USB.