The Role of Forward Converters

Forward converters—also referred to as forward-converter transformers or transformers for forward-mode topology—are used in DC-DC conversion applications to provide voltage transformation and circuit isolation. They increase or decrease the voltage levels of DC input, depending on the duty cycle and number of windings. Compared to alternative topologies, they offer greater design simplicity, multiple isolated output potential, and ease of use.

The following article provides an overview of forward converters, outlining the types available, how they compare to flyback transformers, and typical end applications.

Types of Forward Converters

There are three main types of forward converters available:

Active Clamp Forward Converters

Active clamp forward converters have compound gates that move quickly to reduce switching losses during power conversion cycles. When voltage passes through the primary transformer coil, energy immediately transfers from the primary component to the secondary component, prompting current to pass from the output unit to the connected load.

Both forward converters and flyback converters can integrate clamp mechanisms in their designs—forward converters employ active clamps, while flyback converters utilize resistor-capacitor-diode (RCD) clamps. Despite similarities in the terminology, these clamps function and perform differently. For example, active clamps reclaim a large majority of leakage energy and recover almost all magnetizing energy. They also experience smaller energy losses during zero voltage switching and no voltage spike when turned off.

Fig.1: Typical Active Clamp Forward Converter Circuit Diagram

Fig.2: Current Flow w/ Q1 Closed, Q2 Open

Fig.3: Current Flow w/ Q2 Closed, Q1 Open

Single Switch Forward Converters

Employing the design principles used in buck topology, single switch forward converters focus on providing galvanic isolation in applications involving power levels of less than 200 watts. In these converters, closing the active switch connects the supply to the primary, which prompts the rectifier to conduct the current and pass it through the output inductor to the connected load. Until the switch reopens, the current rises linearly. Once the switch is opened, any energy stored in the inductor transfers directly to the load through the secondary diode.

Fig.4: Typical Single Switch Forward Converter Circuit Diagram

Fig.5: Current Flow w/ Switch Closed

Fig.6: Current Flow w/ Switch Open

Two Switch Forward Converters

As the name suggests, two switch forward converters feature two switches that open and close together when prompted. Closing both switches allows energy to transfer from the primary into the secondary. Within the secondary, a tertiary diode conducts energy into the output inductor and the load. Once the switches are opened, energy flowing the tertiary and quaternary diodes flows back into the source. Compared to the single switch topology, the two-switch topology does not require the use of a snubber circuit or demagnetizing winding.

Fig.7: Typical 2-Switch Forward Converter Circuit Diagram

Fig.8: Current Flow w/ BOTH Switches Closed

Fig.9: Current Flow w/ BOTH Switches Open

Differences Between Forward Converters and Flyback Transformers

While forward converters and flyback transformers may look similar, there are several key differences between them. For example:

• Forward converters use transformers to transfer energy, while flyback transformers store energy.
• Forward converters feature a more complex circuit topology as compared to that of flyback transformers.
• Forward converters are suitable for applications that require greater energy efficiency and higher power outputs (100 to 200 watts), while flyback transformers are suitable for power outputs up to 120 watts.

Typical Applications of Forward Converters                              

Fig. 10: Typical Flyback Converter Circuit Diagram

Forward converters find use in the power supplies of a wide range of equipment and systems, including those for the following industries:

• For the military: Military manufacturers use forward converters in unmanned aerial vehicles (UAVs), stun guns, dipole antennas, and more.
• For aerospace: Aircraft have forward converters in their lighting systems, entertainment devices, searchlights, and cameras.
• For renewable energy (i.e., solar power): Forward converters help prepare solar energy for storage and distribution by standardizing the output voltages. These components are in inverters and grid monitors in solar panel systems and built into electrical drive systems, storage inverters, and battery chargers.
• For computers: Forward converters can be found in a variety of powered computer equipment, including laser printers, laptops, and IP routers. Home entertainment systems with set-top boxes that receive digital television broadcasts also use them.

Forward Converter Solutions From MPS Industries

Forward converters allow industry professionals to transform DC input to higher or lower voltage levels to suit the output demands of the end application. Compared to flyback transformers, they are more efficient and accommodate higher power outputs. Available in several different designs, they can meet a variety of power requirements and restrictions.

At MPS Industries, one of our core specialties is the production of forward transfers and output inductors for forward converters. By working closely with customers, our expert team designs and delivers quality magnetic solutions tailored to their exact needs.

We’re proud to serve the following industries:

• Aerospace
• Automotive
• Computers
• Medical 
• Military
• And more

For additional information about our forward converters or our other products and services, contact us today.

Top Automation Processes Used in the Automotive Industry Today

Many industries have adopted automated technologies, such as AI or machine learning. While much of this technology is still in its early stages, it is already doing impressive work—automation in the automotive industry, for example, has led to a steep increase in productivity, even in complex tasks. Here, we’ll discuss four high-tech automation processes utilized by the automotive industry today.

Machine Vision

Machine Vision (MV), also known as “computer vision,” helps automakers to create safer, more robust vehicles that justify higher price points. In fact, the automotive industry was one of the first to adopt this high-end technology.

MV works by using numerous imaging processes to photograph the surfaces of the vehicle that needs to be inspected. These images are processed by analysis software, which typically utilizes the principle of Finite Element Analysis (a computerized technique used to simulate how a product would fare in a real-world scenario of vibrations, forces, extreme temperatures, fluid flow, and other conditions).

In addition to conventional imaging, other images that MV can capture include:

• X-ray imaging
• 3D imaging
• Infrared imaging
• Hyperspectral imaging
• Line scan imaging

This technology saves costs for automakers while allowing them to increase their price points and stay competitive.

Collaborative Robots

Also known as “cobots,” these robots may initially sound like machines that work with humans, but this is generally not the case. In fact, cobots frequently work independently. Per ISO 10218, there are four main types of cobots:

• Safety Monitored Stop
• Hand Guiding
• Speed and Separation Monitoring
• Power and Force Limiting

Designed around their necessary end function, cobots increase speed and productivity by taking on certain tasks normally done by human technicians. Many cobots are designed to multitask alongside technicians, automatically shutting down when the tasks are completed. Cobots can also pause when technicians enter their workspace, meaning that humans can easily take over any aspects of the task as the need arises.

Artificial Intelligence for Driverless Cars

At its core, Artificial Intelligence (AI) is a system that can achieve goals by reacting to its environment. This is particularly beneficial for driverless cars. In this scenario, AI uses smart sensors—including radar and sonar—to create and store an internal map of its surroundings. This allows it to interact with its environment, plotting out the best trajectory and communicating with the vehicle’s actuators.

AI for driverless cars utilizes a number of technologies, including:

• Predictive modeling
• Coded driving protocols
• Obstacle avoidance algorithms
• Smart object discrimination

Use of these technologies enables the AI to differentiate between various objects on the road, navigate around obstacles, predict behavior, and follow traffic laws at all times.

Cognitive Computing in IoT Connected Cars

While AI functions independently in driverless cars, Cognitive Computing (CC) makes use of both AI and signal processing. CC utilizes a variety of technologies, such as:

• Dialog and narrative generation
• Human-computer interaction
• Human language processing
• Reasoning
• Machine learning

Benefits of Cognitive Computing

Driverless cars utilizing AI need to drive alongside vehicles without AI, and are unable to communicate with other cars on the road. The main benefit of CC in IoT connected cars is it can use the Internet to connect to other CC vehicles on the road, making traffic significantly safer and more predictable.

Although this technology is still new, it could prove to be much more advanced than current driverless car systems. Certain automotive companies, including IBM and BMW, are already working on inventing autonomous cars using CC in IoT vehicles. If all cars eventually adopt this technology—allowing them to communicate with each other and recognize human driving patterns—car accidents may be able to be entirely eliminated.

How Magnetic Components Factor In

Magnetic components power much of the technological advances we have outlined above. There are four types of magnetics to be aware of:

• Low frequency: These magnetics range from 50 to 500 Hz. Devices using these magnets include 115V AC equipment such as HVACs and electricity meters.
• High frequency: Ranging from 16kHz to MHz, these magnetics are often used to charge cell phones.
• Non-isolated: This type of magnetic component decreases electric noise.
• Isolated: Isolated magnetics prevent electric shocks.

Aiding Industry Growth

The automotive industry is expected to grow drastically in the upcoming years. Research into materials helps the auto industry grow and continue to find brand-new solutions and uses for various vehicle components, including transformers. Magnetic components also aid in the development of electric cars, as their motor control systems make use of magnetics that draw energy from batteries. As battery quality continues to develop, magnetic parts will also continue to improve.

Automotive Magnetic Components at MPS Industries

The ongoing development of automation in the automotive industry is leading to increases in productivity and, eventually, decreases in accidents and fatalities. At MPS Industries, we offer magnetic components designed specifically to assist the automotive industry in its growth, including:

MPS transformers and inductors are included in the design of the following product applications:

• DC/AC Inverters
• Fuel Pumps
• Backup Sensors
• DC-DC Boost Converter
• Electric and Hybrid Vehicles
• Power Converter Modules
• Particulate Matter Sensors
• Trailer Brake Power Modules

MPS engineers custom-build these magnetics using our automotive clients’ unique electrical specifications. Contact us to learn more about how we can help meet your goals.