The EL+ vHF series was specially developed for avionics applications and forms a regenerative, bidirectional load platform for high-frequency networks from 360-900 Hz. It realistically simulates linear and non-linear loads as well as grid-connected devices and enables high-precision testing with minimal energy requirements thanks to regenerative energy recovery.
General features
- Bidirectional & regenerative: energy consumption and feed-in, significant reduction in test energy requirements.
- Clean mains input: THDi < 3 % and power factor > 0.98 on the mains.
- HF operation 360-900 Hz: ideal for emulating 400 Hz on-board systems and variable frequency.
- Power range: five models from 15 kW to 50 kW, switchable in parallel to increase power.
- Fine control & dynamics: fast transients, harmonic generation up to 50th order (per phase incl. freely selectable harmonics), independent phase configuration.
- Versatile operating modes: constant current (CC), constant power/apparent power (CP/CS), impedance (CZ) as well as step/interference profile tests with µs resolution.
- User-friendliness & openness: 4.3" touch, Modbus TCP/Ethernet, optional analog/digital I/Os, LabVIEW support.
- Master/slave: fibre optic network of several devices, simple scaling from the software.
- Safety & protection: emergency stop, interlock, freely parameterizable alarms/threshold values.
Typical applications include the testing of aircraft generators with variable frequency, the emulation of onboard consumers (linear and non-linear), anti-islanding tests on grid-connected converters, the generation of defined interference profiles (flicker, dips) as well as power and impedance tests on AC systems in the avionics environment.
Model in focus: EL+15 vHF
The EL+15 vHF variant presented here is the compact entry-level model in the series for high-frequency tests. It combines all the software and hardware features of the EL+ vHF family with a particularly handy form factor - ideal for laboratories, test benches and qualification tests with medium power levels.
Power data & suitability
- Nominal power: 15 kW
- Nominal AC current (rms): 20 A (3-channel) / 60 A (1-channel)
- Dimensions (W×D×H): 450 × 770 × 1100 mm
- Weight: approx. 155 kg
- HF range: 360-900 Hz (like all vHF models)
Comparison within the series
Compared to the larger variants EL+20 vHF (20 kW, 26/78 A), EL+30 vHF (27 kW, 40/120 A), EL+40 vHF (40 kW, 52/156 A) and EL+50 vHF (50 kW, 65/195 A), the EL+15 vHF offers the same features:
- Advantages: lower weight/volume, easier integration into existing test benches, cost-efficient solution for typical avionics load cases up to 15 kW.
- Same platform features: identical RF frequency range, identical software interface, identical operating modes (CC/CP/CS/CZ), same power quality (PF/THDi) and protection functions.
- Scalability: if required, master/slave parallelization of several units to increase power.
Product features of the series:
- Mains side (input): 3×400 Vrms + N + PE, voltage range +15 % / -20 %, 48-62 Hz
- Mains quality: THDi < 3 % at rated power, power factor > 0.98 at rated power
- Efficiency (typ.): ≥ 91 % (from 15 kW, depending on model)
- Output (HF-AC, EUT side): 1- or 3-phase operation; permissible voltage up to ±400 Vpk; approx. 35-277 Vrms ph-N / 35-480 Vrms ph-ph; "HV" option up to approx. 295/510 Vrms
- Frequency range (HF): 360-900 Hz
- Modes: CC (program current), CP/CS (power/apparent power), CZ (impedance R/L/C), steps/disturbance profiles
- Dynamics (typ.): Rise times in the ms range (load/power steps), fine 10 mA/1 W setpoint resolution
- Harmonics: Generation up to 50th order per phase incl. freely selectable harmonics; non-linear load emulation
- Phase configuration: Independent setting values per phase (current, phase angle, harmonic content)
- Overload capacity: up to 125 %/10 min, 150 %/1 min, 200 %/2 s (depending on model)
- User interface & interfaces: 4.3" touch, open Modbus TCP/Ethernet interface, optional RS485/CAN/RS232 gateways; analog/digital I/Os
- Master/Slave: fiber optic network of up to 8 units (AC parallel; DC parallel/serial/serial-parallel depending on mode)
- Safety & measurement: emergency stop, interlock, freely configurable alarms; measured values incl. U/I/P (rms), frequency, temperatures, data logging
- Environment: 5-40 °C, up to 95 % r. h. (non-condensing), forced ventilation
- Acoustics (typ.): < 52 dB(A) for models up to 60 kW
- Dimensions/weight (typ. Cabinet up to 60 kW): approx. 450 × 770 × 1100 mm; ~200 kg (depending on model; EL+15 vHF ~155 kg)
- Standards/compliance: CE, EN-50178/EN-62040-1 (safety), EN-62040-2 (EMC), RoHS
