Elgar - Solar Array Simulator (SAS) - Photovoltaic Emulation

Overview
Specifications & Details
Datasheets & Downloads
Videos

Spin mode is a dynamic mode intended to provide a simulation of a spinning satellite.
Enhanced Eclipse mode is a dynamic mode that allows the user to easily program and initiate an eclipse event with total control over all of the V-I curve parameters and dwell times.
Operates with Sequential Shunt Regulators and Maximum Power Point Trackers
Multiple redundant OVP/OIP layers

Manufactured By: AMETEK Programmable Power

A spacecraft solar array is subjected to large temperature excursions, varying insolation (the amount of sunlight falling on the array), mechanical changes and aging, which substantially effect both its short and long term performance. In order to test the spacecraft's power environment, a cost-effective solution for ground based testing is to utilize a solar array simulator.

The Elgar SAS system reproduces all possible solar array outputs, based on the wide variety of input conditions that an array faces, including orbital rotation, spin, axis alignment, eclipse events, beginning-of-life and end-of-life operation. The SAS also provides complete programmable control of all the parameters that shape the solar cell I/V output curve. By being able to accurately simulate solar panels under various space conditions with complete control, a system developer can comprehensively verify design margins and quickly test, in production, spacecraft power systems and their associated electronics.

Each Solar Array Simulator is a fully integrated, turn-key system complete with Windows NT graphical user interface and hardware control software. It can be remotely controlled and addressable as a single device when integrated into a customer's test system. This control is accomplished via a standard ethernet or optional GPIB interface using standard SCPI format commands.

As a very important consideration in spacecraft testing, discrete hardware protection systems are a standard part of every SAS. These include subsystems that can remove power at the output of the SAS in under 10 microseconds. Each SAS string has an electronic circuit breaker and relay disconnect, so faults are localized and minimize disruption of the last process. SAS systems have been designed and delivered ranging from desktop, 2 channel, R&D units to systems capable of controlling two 64 channel SAS systems simultaneously. AMETEK's Engineered Solutions Group can assist in defining special requirements and customize each system using a standard building block approach. This allows each customer to get exactly what id needed while minimizing costs.

Total Control Of I/V Behavior. AMETEK's Fast Profiling Current Source (FPCS) provides the ability to simulate real world solar array power more accurately than other technologies by allowing programmable control of all four parameters necessary to independently control the characteristic I/V diode output curve, or profile, of each FPCS channel.

In addition, the user may choose the nonparametric mode of operation and program I/V curves unique to the application. The basic building block of an Elgar SAS is the FPCS. Each FPCS module simulates either one or two array strings, or can be series or paralleled with other FPCS modules to simulate larger array segments.

Each FPCS channel delivers 450W or 500W of power; 2 channels are housed in a single 5-1/4" chassis. Open circuit voltage and short circuit current are scaled to meet a customer's

Total control of I/V behavior
Designed to operate at the knee
Fast profiling current source
Bus overvoltage protection
Hardware shutdown system
Multiple master SAS systems can be connected to create very large SAS systems
Customer defined output connectors

Output Ratings
450W or 500W per channel with two channels housed in a single 5-¼ inch chassis
900W or 1000W per channel with one channel per chassis
Output voltages available from 60V to 200V

Input AC Power
AC Input	208V L-L, 3 phase 60 hertz 400V L-L, 3 phase 50 hertz
Programming Accuracy	- at 25˚C ± 5˚C
Voltage	0.1% of full scale voltage
Current	0.5% of full scale source current

Readback Accuracy - at 25˚C ± 5˚C
Voltage	0.2% of full scale
Current	1.0% of full scale source current

Accumulator Accuracy
State of Charge	±2.5%

RMS Ripple and Noise
Voltage	0.5% of maximum output voltage
Current	0,1% of maximum output current

Transient Response

Load Switching Recovery Time
less than 2.5 microseconds to recover to within 90% of programmed value when switched from a short to a load.

Sensor Simulator Options
Cell Open and Short
Switch Closures
Cell Voltage Simulation
Heater Loads
Voltage Monitors	The voltage monitors are A-D converters that can monitor any voltage up to 100VDC
Thermistor	The Thermistors are programmable 12-BIT resistive ladder circuits designed to emulate the readings that a battery thermistor would provide. They are manually programmable from the Sensor Simulator GUI or remotely through the BSS system's remote control input.
Strain Gauge Outputs	The strain gauge outputs are programmable D-A outputs that emulate a battery strain gauge output. The sensor simulator software will cause the output of the strain gauge to output a signal when an excitation voltage is provided by the spacecraft.
Strain Gauge Excitation Sensing	This is an input signal is received from the spacecraft.