Unleashing The Power of Engineering Excellence

Rhombus is the “Power House” of Power Electronics engineering knowledge and experience. We have the expertise, experience, history, talent and track record necessary to provide innovative solutions to the market. Our DNA has been shaped by the early years of electric/hybrid vehicle technology development for the automotive industry. Robust, systems approach is our cornerstone.

Technologies We Provide

Advanced Power Electronics

Rhombus designs and develops advanced power electronics products for electrical energy conversion and control. Designs are base on the latest solid-state power semiconductors, proprietary topologies and algorithms, digital signal processors (DSP) based control architecture, and advanced communication and data management processes. Our products are optimized from a total system perspective by carefully balancing conflicting priorities of size, cost, efficiency, isolation, thermal management, reliability, distortion, and capability.

Energy Management & Controls Software

We utilize advanced closed loop controls in our converters running on ultra fast DSP. The DSP takes in multiple signals (voltage, current, frequency, thermal, etc.) to continuously process and output signals to control multiple power switches. It is not uncommon for a machine to have multiple DSPs running tens of thousands of lines of embedded firmware to manage the complexities involved in an advanced power converter. How this firmware gets implemented and tuned is the core IP for Rhombus.

We also have an embedded controller in each machine that runs the data acquisition logging, data bases, external communications and power applications. The combined hardware and software is called VectorStatTM. VectorStat operates in a peer-to-peer configuration allowing multiple machines to communicate as a system. The computer processing capabilities enable complex optimization algorithms and provide intelligent communications over smart power networks. The distributed design ensures all electrical demand is satisfied while maximizing efficiency and eliminating single points of failure.

Energy Storage

Batteries provide critical energy storage for on-grid and off-grid applications. As renewable sources become a larger percentage of the electrical power consumed, batteries are needed to buffer the intermittent supply and demand. Power converters enable batteries to be used by converting power from AC to DC to charge batteries and from DC to AC to use the energy stored in batteries. Every energy storage system (ESS), depending on type of batteries, operates at different voltage ranges and charge / discharge rates. Our power converters are a core part of an ESS, and are tuned to optimize each ESS.


Microgrids are defined as having at least one energy storage system, at least one source of energy and at least one load of energy. As the number of nodes increase, so does the complexity of managing the flow and balance of energy in the system. Our power inverters operate at the hub of a microgrid, controlling the flow of energy between multiple supply and demand nodes.

Regenerative Testing

Batteries, internal combustion engine generator sets (Gen-Sets) and power supplies all need to be life time tested and cycled for engineering evaluations or for production testing. Traditionally, static loads were used for these applications wasting significant electrical energy in the process. Our power converters, configured for testing, can be used in place of static loads providing rigorous dynamic testing and regenerate 80% of the energy back to the grid. Our DC and AC dynamic loads can be used in multiple testing applications with enhanced bandwidth, and come with sophisticated programmable user interfaces.

How can we help you?

Rhombus Services your energy management needs

Rhombus understands that selecting the correct power converter and integrating it into a larger system can be a daunting task.

Let us help you. We offer a wide range of products that may perfectly suit your requirements. In many cases, we can make minor modifications to existing standard products without significant additional cost.

Learn More About Product Sales Suport

Rhombus has a large staff of experienced engineers in multiple disciplines.

Whether you need us to critique your product design, provide innovative alternative approaches to a system, or conduct simulations or thermal studies; we have the flexibility to complement your engineering team and add tremendous value on compressed time schedules. Let us be an extension of your engineering team, giving you more technical capabilities to complete your projects on time and within budget.

Learn more about technical consulting

Rhombus is a collaborative advance power system design & development team.

We approach each opportunity from the needs of the customer, understanding the program and ensuring we are addressing the right challenges early in the process. We take a phased approach to product development with a small, focused team that integrates with your group for win-win solutions. We are adaptive and flexible, whether it is customizing a standard product or developing the next generation product from the ground up. We can help you accelerate innovative products to market.

Learn more about product design

Rhombus has tremendous experience in global manufacturing and assembly of power systems.

We use the best DfX methods and can help you seamlessly transfer products from a prototype stage to high volume manufacturing.

Learn More About Manufacturing Support

Rhombus provides high-powered test capabilities for inverters and other power conversion products.

Our High-Power Energy Lab in Dearborn, Michigan contains sophisticated equipment for product development, testing and validation of regenerative grid-tied or island-mode power conversion devices. The lab has 4 test bays each with 350kVA capacity or can be combined for higher loads. Capable of testing to UL and California Energy Commission (CEC) efficiency standards, the lab allows us to test the limits of power converter and battery designs to readily and quickly adapt to evolving state, national and international regulations.

Learn More About High Power Energy Labs

Our Process

Consider Rhombus an extension of your product development team and your confidential innovation engine.


Our team is quick to understand the problem and provide multiple paths to a robust solution. We do not “sell” a solution or product that is not in your best interest.

Customized Solutions

The success of our programs is determined by a thorough evaluation of the product requirements, scope, and responsibilities. Once this step is completed we will accurately estimate the cost.


Rhombus takes an open book approach when developing innovative products. We involve the customer in all aspects, and every step of the way, working side-by-side with your team to eliminate that ‘Not Invented Here’ mentality.


We transfer product knowledge, documentation and ownership to our customers. We will support the initial production build, certifications, and testing validation.

How We Work


We offer standard or customized products for optimized solutions. Our experience reduces risk & provides innovative ideas to solve problems.


We have 20 years of algorithm development for every operational requirement and offer budget flexibility by applying only the resources you require.

Our Clients & Partners

  • Underwriters Laboratories
  • University of St Thomas
  • Cummins
  • OutBack Power
  • Alpha
  • EnerSys
  • Johnson Controls
  • Ametek