3 Functional description
High voltage power supplies of the device class EPS are supplied from a DC voltage and generates a stable output voltage up to
the nominal voltage.
The units can be controlled via the specified connector with analogue and digital signals. The INHIBIT function is used to disable
and block the generation of high voltage.
In the following, the working principle of the power supply will be described. Next to the DC input there is a EMI/RFI filter, which
feeds the DC link. The DC link voltage is buffered by electrolytic capacitors. An inverter with a connected resonance circuit
transforms the DC link voltage into a controllable sinusoidal voltage. The HV transformer and HV rectifier provide an output
voltage corresponding to the external set voltage. Output voltage and current are measured by high precision voltage dividers
and a shunt and are fed back to the control circuit. A damping resistor connected to the output capacitance limits the output
current during a load change or ARC.
High voltage power supplies of this class work with a fixed switching frequency. The output parameters are controlled via a pulse
width modulation (PWM). The control circuit controls and limits the output voltage and current corresponding to the set values.
Normalized monitor voltages for voltage and current are provided for read back. The control circuit is also monitoring the input
voltages, auxiliary voltages and the temperatures of cooling air and single components.
Optionally, the device can be equipped with:
•
the option capacitor charger (CLD – very low overshoot of the output voltage),
•
an interlock safety loop, which safely interrupts the HV generation,
•
an ARC management with fixed parameters, which protect the device against overload in the event of permanent
arcing,
•
lower ripple and noise of the output voltage (VLN – very low noise).
3.1 Electrical wiring of the high voltage output
Figure 1: Electrical wiring of the high voltage output
EPS High Voltage Power Supply series | Last changed on: 2020-12-02 |
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