Three independent phases
Voltage, phase angle and programmable routines can be defined separately for phases A, B and C.
ESA – Configurable High-Power AC Power Supply up to 10 MVA
For custom test systems with independently controlled phases, programmable grid events and optional regeneration.
The ESA Series is a modular three-phase AC power source with configurable voltage, current and power ranges. With the -R option, it operates in four quadrants as a regenerative grid simulator; further options add regenerative load, DC output and line-impedance functions for demanding test systems.
Reproduce grid disturbances
Sequences, harmonics, interharmonics and LVRT/HVRT profiles reproduce defined grid events repeatably.
Source and load
The -R and -LD options add regenerative power flow and regenerative AC load modes.
Ready for automation
LAN, RS485, SCPI, Modbus and stored test sequences support integration into automated test systems.
Personal project consultation
Do you need support selecting the right power supply? Our technical specialists will provide personal advice tailored to your application.
Select the appropriate technical configuration or access product documentation directly.
ART. NO.
Description
Current [A]
Power [P]
Voltage [V]
ESA 45-300-68
|
Description
ESA 45-300-68 Bidirectional programmable AC source, 45 kVA, 300 V L-N, 68 A/phase
|
Current [A]
91
|
Power [P]
45000
|
Voltage [V]
300
|
AC Source/ Load (1/3ph)
Technical Data
Product category
AC Bidirectional
AC Electronic Load
AC Power Supply
Type of AC Load
Regenerative Load
Type of AC source
Source + Load
Grid simulator
Single-/Three-phase
ESA 60-300-91
|
Description
ESA 60-300-91 Bidirectional programmable AC source, 60 kVA, 300 V L-N, 91 A/phase
|
Current [A]
182
|
Power [P]
60000
|
Voltage [V]
300
|
AC Source/ Load (1/3ph)
Technical Data
Product category
AC Bidirectional
AC Electronic Load
AC Power Supply
Type of AC Load
Regenerative Load
Type of AC source
Source + Load
Grid simulator
Single-/Three-phase
ESA 180-300-273
|
Description
ESA 180-300-273 Bidirectional programmable AC source, 180 kVA, 300 V L-N, 273 A/phase
|
Current [A]
273
|
Power [P]
180000
|
Voltage [V]
300
|
AC Source/ Load (1/3ph)
Technical Data
Product category
AC Bidirectional
AC Electronic Load
AC Power Supply
Type of AC Load
Regenerative Load
Type of AC source
Source + Load
Grid simulator
Single-/Three-phase
ESA 240-300-364
|
Description
ESA 240-300-364 Bidirectional programmable AC source, 240 kVA, 300 V L-N, 364 A/phase
|
Current [A]
364
|
Power [P]
240000
|
Voltage [V]
300
|
AC Source/ Load (1/3ph)
Technical Data
Product category
AC Bidirectional
AC Electronic Load
AC Power Supply
Type of AC Load
Regenerative Load
Type of AC source
Source + Load
Grid simulator
Single-/Three-phase
ESA 300-300-455
|
Description
ESA 300-300-455 Bidirectional programmable AC source, 300 kVA, 300 V L-N, 455 A/phase
|
Current [A]
455
|
Power [P]
300000
|
Voltage [V]
300
|
AC Source/ Load (1/3ph)
Technical Data
Product category
AC Bidirectional
AC Electronic Load
AC Power Supply
Type of AC Load
Regenerative Load
Type of AC source
Source + Load
Grid simulator
Single-/Three-phase
ESA Custom
|
Description
ESA Customized Customized bidirectional AC source, project-specific configuration
|
Current [A]
10000
|
Power [P]
10000000
|
Voltage [V]
50000
|
AC Source/ Load (1/3ph)
Technical Data
Product category
AC Bidirectional
AC Electronic Load
AC Power Supply
Type of AC Load
Regenerative Load
Type of AC source
Source + Load
Grid simulator
Single-/Three-phase
ESA Series overview
The ESA Series is a modular three-phase AC power source for grid simulation, power-electronics development and automated testing. Standard models cover 45 to 300 kVA at 0 to 300 V L-N; voltage, current, power and input connection are configured for the project. Three DC/AC power channels generate independent phase outputs. Standard operation provides AC output, CV and CC control, sequences, harmonics, interharmonics, user-defined waveforms, measurement functions and both local and PC-based operation.
The -R option adds four-quadrant operation with bidirectional energy flow, turning the ESA into a regenerative grid simulator. -LD expands this configuration with regenerative AC load modes, while -DC adds DC and AC+DC output. Further options cover line-impedance simulation, single-phase operation, islanding scenarios and customer-specific frequency ranges. The hardware can therefore be configured for the specific test task without treating optional functions as standard equipment.
Key benefits
Bidirectional grid operation
With -R, the ESA operates in four quadrants and returns absorbed energy. This supports tests with changing active-power direction.
Fast voltage transitions
Voltage rise and fall times are below 1 ms in the standard configuration, enabling dynamic dips and recovery profiles.
Programmable power quality
Harmonics up to the 50th order and interharmonics are programmed per phase by amplitude and angle.
Voltage at the DUT
Remote sense feeds the load voltage back into the control loop, compensating for voltage drops in the connection leads.
Repeatable test profiles
Multi-step routines combine setpoints, ramps and dwell times. Settings can be saved and imported for recurring tests.
Measurement and waveform recording
DSP/FPGA control supports real-time measurements plus waveform display and storage at a 10 k/s sampling rate.
How the three-phase AC power source works
In the standard topology, the three-phase mains input is followed by a transformer, filters and a PWM AC/DC stage. The resulting DC link supplies three DC/AC power modules that generate phases A, B and C independently. Voltage or current is regulated in CV or CC mode; frequency and phase angle are programmable. The topology of a unit with -R is designed for bidirectional energy flow and differs from the standard configuration.
STD mode is used for individual operating points. SEQ and List modes link multiple steps with ramps, dwell times, phase angles and optional waveform components. The graphical user interface runs on the front Windows touch panel and can also be used on a connected PC. Measurements, status, faults and input/output waveforms are displayed centrally.
Power range and standard models
The following standard models provide an AC output up to 300 V L-N. Current is specified per phase; dimensions and weight refer to the respective cabinet configuration.
| Model | Power | Voltage L-N | Current per phase | W × D × H | Weight |
|---|---|---|---|---|---|
| ESA 45-300-68 | 45 kVA | 300 V | 68 A | 800 × 800 × 2,000 mm | 770 kg |
| ESA 60-300-91 | 60 kVA | 300 V | 91 A | 800 × 800 × 2,100 mm | 980 kg |
| ESA 120-300-182 | 120 kVA | 300 V | 182 A | 1,600 × 900 × 1,700 mm | 1,400 kg |
| ESA 180-300-273 | 180 kVA | 300 V | 273 A | 1,600 × 900 × 2,100 mm | 1,800 kg |
| ESA 240-300-364 | 240 kVA | 300 V | 364 A | 1,800 × 900 × 2,100 mm | 2,100 kg |
| ESA 300-300-455 | 300 kVA | 300 V | 455 A | 2,000 × 1,000 × 2,100 mm | 2,700 kg |
Check the configuration: The model code follows ESA AAA-BBB-CCC-DDD/EEE for power, voltage, current per phase, options and input connection. Customer-specific units may differ; the quotation, nameplate and project-specific design define the delivered configuration.
Dynamics, accuracy and regulation
| Characteristic | Value / condition | Relevance |
|---|---|---|
| Voltage rise, 0–90% | <1 ms standard; <2 ms with -TR | Dynamic setpoint changes and ride-through profiles |
| Voltage fall, 90–0% | <1 ms standard; <2 ms with -TR | Defined dips and shut-down transitions |
| Load regulation | 0.2% FS | Limited output deviation during load changes |
| Line regulation | 0.1% FS | Limited output deviation during input variation |
| Output-voltage THD | <1% FS with resistive load at 50/60 Hz | Defined sinusoidal reference conditions |
| Programming accuracy | Power 0.3% FS; voltage 0.1% FS standard / 0.2% FS with -TR; current 0.2% FS | Classification of programmed setpoints |
| Frequency / phase | 0.01 Hz; ±0.3° at 50 Hz | Precise frequency and phase control |
| Resolution | 0.1 kW; 0.01 V; 0.1 A; 0.01 Hz; 0.1° | Fine increments for programmed test parameters |
Operating modes and options
| Function | Configuration | Operation and use |
|---|---|---|
| CV / CC | Standard | Regulates AC output voltage or current for individual operating points and programmed routines. |
| STD, SEQ and List | Standard | Single-step, multi-step sequence or freely combined command lists with ramps, dwell times and loops. |
| Four-quadrant operation | -R | Sources and absorbs AC power for regenerative grid simulation and bidirectional testing. |
| Regenerative AC load | -LD together with -R | CR, CC, CP and rectifier modes for resistive, inductive, capacitive and nonlinear load profiles. |
| DC and AC+DC | -DC | Adds DC output and a DC component to the three phase channels. Up to 50% output power is available in DC mode; current is derated below 30 Hz. |
| Line impedance | -IMP | Simulates R and L at the output; Rmax = 0.2 × Urated / Irated, Lmax = Rmax / 314. |
| Single-phase output | -1P | Parallel connection of the three phase outputs raises available single-phase current to the sum of the channels. |
| Islanding detection | -62116 | RLC load simulation for anti-islanding tests with a sine waveform and 50/60 Hz input. |
| Active/reactive power control | -PQ | Decoupled P and Q setpoints for energy-flow and power-system research. |
| Extended frequency | -HFXXX | Customer-specific extension of the AC frequency range in CV mode. |
Typical applications
Grid-connected generation systems
With -R, the ESA generates voltage and frequency deviations, phase jumps, unbalance and LVRT/HVRT profiles for compliance testing.
Anti-islanding tests on PV inverters
The -62116 option reproduces an RLC load in two parameter modes and measures islanding protection time at 50 or 60 Hz.
Solid-state transformers and microgrids
With -PQ, active and reactive power are set independently to investigate power transfer and load balancing between grid sections.
Motor drives and power electronics
Independent phases, programmable frequency and user-defined waveforms supply converters and assemblies under repeatable conditions.
Automated production testing
Remote setpoints, sequences, SCPI/Modbus plus status and fault feedback integrate the power source into automated test stands.
Power-quality research
Harmonics, interharmonics, unbalance and user-defined waveforms enable controlled investigations of three-phase DUTs.
Interfaces, software and automation
| Equipment | Availability | Function |
|---|---|---|
| LAN | Standard | Remote control from a PC in the same network segment; local touch-panel communication uses separate internal LAN ports. |
| RS485 | Standard | Remote control and noise-resistant multidrop communication over a two-wire link with signal ground. |
| SCPI / Modbus | Supported protocols | Programmed setpoints, operating modes, measurement queries and status control. |
| RS232 | -232 | Point-to-point remote control through the optional serial interface. |
| Analogue input | -ATI | External output-voltage setpoint control through BNC connectors. |
| TTL output | Standard | Provides an observable trigger signal when voltage or frequency changes. |
| Remote sense | Standard | Regulates voltage at the DUT connection point rather than only at the instrument terminals. |
| Windows GUI | Standard | Operation on the at least 12-inch touch panel or a PC, measurement display, waveform capture, storage and fault display. |
Parallel operation and scaling
Units of the same model can operate in parallel with the -MS option. One unit is configured as Parallel Master and the other as Parallel Slave; communication uses optical fibre. Input and output connections are wired in parallel accordingly. Setpoints are entered at the master, while each unit's measurement page displays its local values.
System design: Parallel operation requires identical units, the intended master-slave connection and project-specific AC/output cabling. Confirm the permitted unit count and total power for the specific configuration.
Installation and infrastructure
| Characteristic | Requirement / configuration |
|---|---|
| AC input | Depending on the order: 380, 400 or 480 V L-L ±10%, as 3P+N+PE or 3P+PE; check the actual configuration on the nameplate. |
| Input frequency | 47–63 Hz |
| Output | Three-phase N/A/B/C; standard range 0–300 V L-N |
| Cooling | Forced-air cooling; water cooling with -W. Allow at least 600 mm clearance from walls or other equipment for ventilation. |
| Operating temperature | 0–40 °C |
| Humidity | 20–90% relative humidity, non-condensing |
| Connections | Cable entry from below; input and output busbars plus PE connection are designed for the project's voltage, current and cooling configuration. |
Before installation, check the model, voltage and current ratings on the nameplate. Protective earth, AC supply cable, output wiring, upstream switching equipment and floor space must be sized for the specific cabinet configuration.
Protection and safety functions
The ESA monitors overcurrent, overvoltage, overpower and overtemperature. The user interface also provides settings for undervoltage, peak-current limitation, and voltage and current ramps. If a configured OCP, OVP or OPP threshold is exceeded, the output is switched off; status and faults are shown in the GUI.
An emergency-stop button is located on the front panel. An external emergency-stop interface is also provided for connection of a customer-side switch. These instrument functions do not replace the risk assessment and protective architecture of the complete test stand.
ESA FAQ
Is every ESA configuration bidirectional?
No. Four-quadrant operation with regenerative energy flow is provided by the -R option. Standard and optional equipment must match the individual configuration.
Which standard models are documented?
The standard overview contains six models from 45 to 300 kVA, each up to 300 V L-N and with 68 to 455 A per phase.
Can the three phases be set independently?
Yes. Voltage, phase angle, sequence, harmonic and interharmonic parameters can be defined individually for each phase.
Can the ESA operate as a regenerative AC load?
Yes, with -LD together with -R. CR, CC, CP and rectifier modes are available; the phase angle in CC/CP ranges from +90° to -90°.
Is DC output available?
The -DC option provides DC and AC+DC operation. Up to 50% output power is available in DC mode; current is derated below 30 Hz.
How is voltage drop in the load leads compensated?
Remote sense measures voltage at the DUT input and feeds it back to the control loop. The factory terminal link is rewired accordingly.
Can the ESA perform grid-fault and ride-through tests?
With -R, the ESA generates voltage and frequency deviations, dips, unbalance and LVRT/HVRT profiles for grid-connected DUTs.
Can the ESA support anti-islanding tests on PV inverters?
With -62116, the ESA simulates an RLC load for anti-islanding tests. This function is limited to a sine waveform and 50/60 Hz input.
How is the ESA integrated into automated test stands?
LAN, RS485, SCPI and Modbus control setpoints and read measurements or status data. Sequence and List modes implement repeatable development and production routines.
Technical consultation and project enquiry
To select an ESA configuration, provide power, voltage and current per phase, input supply, frequency range and required operating modes. Also specify dynamics, waveform, load or grid-simulation functions, interfaces, cooling and the planned parallel configuration.
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