New Industry Products

Programmable Power Sources Handle Variety of Grid-level Applications

December 12, 2022 by Mike Falter

New Sequoia and Tahoe Series generate precision AC and DC power signals for regenerative load simulation and complex power system development.

AMETEK Programmable Power has released two new families of precision programmable AC and DC sources under its California Instruments brand. The Sequoia Series is a grid simulator with an optional mode that allows it to function as a regenerative electronic load simulator for EVSE (electric vehicle supply equipment), V2G (vehicle to grid), and other AC power generation system testing. Tahoe is a series of high-power sources capable of delivering up to 90 kilowatts (KW) of simulated three-phase grid power from a single unit or up to 1 megawatt (MW) when using multi-unit configurations.


Sequoia and Tahoe precision programmable sources.

Sequoia and Tahoe precision programmable sources. Image used courtesy of AMETEK


Both platforms integrate the latest silicon carbide (SiC) power-switching technologies for improved efficiency and performance at high voltage. The new series are positioned as potential upgrades to AMETEK’s existing MX, RS, and BPS Series.

The sources are highly configurable and can be programmed for a range of test conditions. Besides grid power levels, the sources can also generate lower, single-phase AC voltages at frequencies approaching 1 kilohertz (kHz) with 0.02 percent accuracy. High and low ranges are also available for generating DC signals from 0 to 440 volts DC. This configurability makes Sequoia and Tahoe suitable for a wide range of system test applications including power generation, avionics, EVSE, and manufacturing line equipment.


Wind Turbine System Development

A good example of where these programmable supplies are useful is in wind turbine system development. A typical wind turbine power plant is a complex system with multiple power conversion steps that ultimately translate kinetic energy from the wind into usable grid power.

In a typical wind power system, “dirty” AC power is generated from the spinning turbine through a gearbox and generator mechanism. This AC power is not suitable for the grid and needs to be converted to DC power for longer-term storage (batteries etc.), or to be inverted back to clean, grid-capable AC power. 

Each phase of this power conversion process needs to be designed for precision, independently tested, and evaluated. Precision sources, including the Sequoia and Tahoe series, can generate AC and DC power signals needed to simulate and test each phase of the power system, ensuring they work together seamlessly.



Wind turbine power generation.

Wind turbine power generation. Image used courtesy of AMETEK

Q&A With AMETEK Product Manager

EE Power had the opportunity to ask John Hernandez, AMETEK AC product manager, to share some of his insights on the new Sequoia and Tahoe supplies:

EE Power: These new products are designed as upgrades to your existing MX, RS, and BPS Series. What are some of the key feature improvements over those existing products?

Hernandez: The product refresh was focused on three aspects: 

  1. Add the Programmable, Regenerative eLoad capability

  2. Modernize the power-switching architecture and reduce material/manufacturing costs while retaining all of the features, functions, and capabilities that our customers have grown accustomed

  3. Align the appearance with the ASTERION product family

EE Power: Do you have any early adopters for either the Sequoia or Tahoe series? If yes, what applications and/or customer requirements are leading the move to these newer products?

Hernandez: Early adopters are in the EV (electric vehicle) charger space. Their requirements include grid simulation for V2G (vehicle-to-grid) testing.

EE Power: What efficiencies can be achieved when returning power to the grid?

Hernandez: There will always be a limited supply of energy, and therefore, the cost of energy will always be high. Historically, power test applications have dissipated energy in the form of heat. By returning energy to the grid, users can now reduce their losses in the form of dissipation and therefore reduce their overall test costs.


Power Regeneration Becoming Essential

As systems such as EV chargers and bidirectional onboard chargers (OBC) for V2G applications continue to increase in power, it is no longer practical or affordable to simply dissipate this energy as heat during system load testing. Costs include direct energy costs and costs associated with cooling systems (fans, etc.) needed to remove heat from the local environment. The ability to store and return energy used during testing to the grid will be essential for manufacturers of high-power systems to meet product and development cost goals.



EV bidirectional charging.

EV bidirectional charging. Image used courtesy of AMETEK