Yaskawa Frequency Drives: Technology, Applications, and Comparisons

Understanding Variable Frequency Drives (VFDs)

A Yaskawa frequency drive, commonly referring to Yaskawa's variable frequency drives (VFDs), is a type of electronic controller used to adjust the speed and torque of AC electric motors. In essence, a VFD protects and controls an AC motor by varying the frequency and voltage of the power supplied to that motor. By converting fixed utility AC power to DC and then inverting it back to AC at a desired frequency and amplitude, VFDs can smoothly ramp motors up to speed or down to stop. This ability to precisely regulate motor speed not only provides process control but also yields significant benefits in energy efficiency and mechanical wear reduction. Unlike across-the-line starters that slam a motor directly to full speed, a VFD can soft-start a motor by limiting inrush current and gradually accelerating the load, greatly reducing torque shocks to belts, gears, and couplings. Likewise, controlled deceleration prevents water hammer in pumping systems and other abrupt stops that could damage equipment. In short, VFDs (also known as adjustable frequency drives) give engineers fine-grained command over motor-driven systems, which is invaluable for optimizing performance in industrial applications.

Yaskawa's Leadership in Variable Frequency Drives

Yaskawa Electric is widely recognized as a global leader in drive technology. In fact, Yaskawa is the world's largest manufacturer of AC variable frequency drives for industrial automation and OEM applications. The company's portfolio spans from tiny fractional-horsepower microdrives to high-power units driving thousands of horsepower. Today, Yaskawa's industrial AC drive family alone covers ratings from 1/8 HP up to 2250 HP, encompassing virtually every automation need. This broad range reflects over a century of expertise – Yaskawa was founded in 1915 – and a track record of innovation. Notably, Yaskawa developed the world's first transistor-based PWM inverter drive in 1974, a breakthrough that helped usher in the modern era of solid-state motor drives. The company has continued to push the envelope with new technologies and was the first to ship over 10 million VFD units (as of 2008), representing roughly 14% of the global market at that time. Such adoption is a testament to Yaskawa's reputation for quality and reliability. Field data has shown extremely low failure rates for Yaskawa drives (on the order of only 0.0062% field failures), attributed to rigorous manufacturing standards and a culture of continuous improvement. In practical terms, end users experience exceptional longevity and uptime from these drives.

Yaskawa's current product lineup is organized to target different needs while maintaining a high level of performance across the board. Their General Purpose drives (e.g., the GA800 series) are full-featured workhorses up to 1000 HP, suitable for most industrial tasks. Microdrives like the GA500 and earlier V1000 series cover lower power ranges (fractional horsepower up to 25–40 HP) in very compact packages, ideal for space-conscious installations. For HVAC and pumping systems, Yaskawa offers dedicated Fan & Pump drives such as the FP605 and P1000, which are optimized for variable torque loads. Yaskawa even provides specialty designs; for example, the company's U1000 Matrix Drive uses a matrix converter topology (direct AC-to-AC conversion) to achieve low input harmonics and full regenerative braking capability, without the need for a DC bus capacitor or separate regen module. The U1000 series, available up to 800 HP, is a unique solution for applications requiring ultra-clean power and energy recapture. Yaskawa has also explored multi-level inverter technology; its earlier G7 drive was the only low-voltage VFD of its time to use a 3-level neutral-point clamped architecture. This 3-level design (available through 500 HP) dramatically reduced dV/dt and common-mode voltage on long motor leads, mitigating issues like motor insulation stress and bearing currents. These examples illustrate Yaskawa's engineering focus on solving real-world problems (harmonic distortion, regeneration, long-lead effects, etc.) through innovative drive hardware.

Advanced Control and User-Friendly Design

Crucially, Yaskawa embeds the latest control algorithms and user-friendly features across its range. Even the standard drives incorporate vector control capability, allowing tight regulation of motor speed and torque (including operating closed-loop with encoder feedback, or sensorless in many cases). The drives are known for excellent low-speed performance and high starting torque – necessary for heavy industrial loads. Yaskawa's design philosophy emphasizes out-of-the-box ease of use as well: drives are typically factory pre-programmed with default settings, and an intuitive multilingual LCD keypad facilitates quick setup and diagnostics. For instance, parameters can be easily copied from one drive to another via the keypad's memory or using a portable USB copy device on certain models. All Yaskawa drives include extensive built-in protections (overcurrent, overvoltage, phase loss, overheating, etc.) and self-diagnostic codes to streamline troubleshooting. Additionally, software tools like DriveWizard provide PC-based commissioning, monitoring, and tuning capabilities for Yaskawa drives. In summary, Yaskawa's position as an industry leader comes not just from the volume of drives deployed, but from a combination of wide power range, pioneering technology, high reliability, and user-centric design that has consistently set their products apart.

Key Technical Features and Standards

Modern VFDs, including those from Yaskawa, share a core set of technical features that ensure they can be safely and effectively applied in industrial environments. At a fundamental level, a VFD's power stage is comprised of a rectifier, a DC bus, and an inverter. The rectifier (diode or transistor-based) converts incoming AC line power to DC; the DC bus smooths and stores this energy (often with the help of capacitors and reactors); and the inverter, using high-speed insulated-gate bipolar transistors (IGBTs), chops the DC into a pulse-width modulated AC output of controlled frequency. This architecture gives fine control over motor speed according to the formula N = 120·f/P (where f is frequency and P the number of motor poles). Most industrial drives can output frequencies from near-zero up to about 400 Hz or more, covering a wide speed range including overspeed when needed. (For special cases like spindle drives, Yaskawa even allows up to 1000 Hz output on certain VFD models.) Crucially, the inverter's PWM switching also lets the drive regulate output voltage in proportion to frequency, maintaining the optimal volts-per-hertz ratio or performing field-oriented vector control as required by the motor. This coordination of voltage and frequency is what enables VFDs to deliver constant torque at low speeds and to avoid saturating or under-fluxing the motor throughout the speed range.

Another important aspect of VFD technology is the control algorithm or motor control method implemented. Simpler VFDs operate in open-loop V/Hz mode, suitable for applications that do not demand high precision. More advanced drives (which include essentially all Yaskawa drives and those of other top manufacturers) offer vector control – where the drive actively models the motor's electromagnetic state to modulate torque and speed with high accuracy. Yaskawa's vector control can be used with or without feedback: in closed-loop mode, an encoder on the motor shaft feeds back speed/position, allowing the drive to hold speed within a very tight tolerance or even perform position/torque control. In sensorless mode, the drive's software estimates motor slip and torque from electrical measurements alone, which is highly effective for the majority of use cases. Different companies have proprietary enhancements to vector control; for example, ABB's high-end drives utilize Direct Torque Control (DTC) – a model-predictive approach that adjusts motor flux and torque in real time without a fixed PWM carrier frequency. DTC is ABB's signature technology and provides extremely fast torque response and accuracy, even at near-zero speed, across various motor types (induction, permanent magnet, etc.). In practice, both Yaskawa's implementations and competitors like ABB, Siemens, or Rockwell achieve excellent performance – but these control philosophies can be a differentiating factor. The upshot is that modern VFDs can maintain stable motor operation under rapidly changing loads or commands, and can often deliver 150% or more of rated torque for short periods to overcome breakaway loads or provide a hard acceleration when needed.

Harmonic Mitigation and Power Quality

Harmonic mitigation and power quality is another key technical area for VFD applications. By nature of their rectifier front-end, standard drives draw current from the supply in a non-sinusoidal manner, which can introduce harmonic distortion (typically the 5th, 7th, 11th, etc. harmonics of the line frequency). Excessive current harmonics can overheat transformers and disturb other equipment, so industry guidelines like IEEE 519 set limits on allowable distortion at the point of common coupling. To help users meet these standards, drive manufacturers build in various mitigation features. Yaskawa, for instance, designs many of its drives with DC link reactors (chokes) or offers them as options. All Yaskawa drives 30 HP and above include a 3% impedance DC bus reactor as standard, and smaller drives up to 25 HP can be ordered with internal 3% or 5% reactors. This added inductance smooths the current waveform and typically cuts input current THD significantly (often into the 35%–45% range from an uncontrolled ~80% THD). For more stringent requirements, Yaskawa and others provide multi-pulse rectifier configurations. Some Yaskawa models are built with dual 6-pulse diode bridges that can be fed in a 12-pulse arrangement (using phase-shifting transformers) to cancel many lower-order harmonics. They even offer factory-integrated 18-pulse drive packages, which include a built-in phase-shifting transformer – these can reduce current distortion to ~5% or less, satisfying very strict IEEE 519 compliance needs. Competing manufacturers likewise have solutions: e.g., ABB's ultra-low harmonic drives use active front-end IGBT rectifiers to actively shape the line draw, and Eaton's drives include options for input filters or 18-pulse arrangements. Yaskawa's aforementioned Matrix Drive (U1000) takes a different approach by eliminating the rectifier/DC-bus stage entirely – it inherently draws near-sinusoidal line currents with very low harmonic content while also enabling regeneration of energy back to the source when a motor is overhauling. For applications like cranes or elevators that frequently brake, regenerative capability can be a huge advantage (energy is returned to the grid or reused, rather than wasted as heat in braking resistors). In summary, users have a toolkit of harmonic reduction strategies available in modern VFD product lines, and a well-chosen drive can meet power quality requirements without need for extensive external filtering.

Communication, Integration, and Safety Features

All major VFDs also come with extensive communication and integration features. It is now standard for an industrial drive to support network communication protocols so that it can interface with PLCs, SCADA systems, or building automation. Yaskawa offers a full suite of fieldbus options – from traditional serial protocols to Ethernet-based networks. For example, Yaskawa drives can be outfitted with or directly support Modbus, EtherNet/IP, PROFINET, EtherCAT, DeviceNet, PROFIBUS, and others for seamless integration. Many of Yaskawa's newer drives (like the GA800) even include built-in Ethernet IP connectivity by default, reflecting a trend across the industry. Eaton's PowerXL DG1 series similarly has standard Ethernet/TCP-IP communications on every unit, so no extra option cards are needed. Besides network comms, VFDs come with a complement of analog and digital I/O for local control: typically analog inputs for speed reference, digital inputs for start/stop and preset speeds, relay outputs for indicating status, etc., all of which are programmable. Additionally, safety integration has become important – most modern drives include an input for Safe Torque Off (STO), which is a functional safety feature that can disable the drive's output to prevent the motor from delivering torque, without completely removing power to the drive. Using STO, systems can achieve compliance with safety standards (e.g., an emergency stop circuit) in a simpler way than using contactors. Yaskawa's drives, for example, can reach up to SIL3 (Safety Integrity Level 3) / PL e (Performance Level e, Cat. 3) ratings for safe stop functions when wired appropriately. This means they're approved for even high-risk safety applications according to IEC 62061 and ISO 13849 categories. From a regulatory standpoint, Yaskawa VFDs carry all the expected approvals: CE marking (meeting the Low Voltage Directive via IEC/EN 61800-5-1 and the EMC Directive via EN 61800-3), UL and cUL listing for use in the US and Canada (tested to UL 61800-5-1 standards), and typically RoHS compliance and others. They are offered in various enclosure ratings – open chassis (IP20) for mounting inside control cabinets, UL Type 1 general-purpose enclosed, and up through NEMA 4X/IP66 washdown enclosures for harsh environments. As one example, Yaskawa's V1000-4X version comes in a NEMA 4X housing suitable for food processing areas, with a protective coating to resist cleaning chemicals. Users should always match the drive's enclosure and environmental specs to their application (temperature, dust or moisture exposure, etc.), but the major manufacturers provide options for nearly every scenario.

Efficiency and Performance

In terms of efficiency, VFDs themselves are highly efficient power converters – usually on the order of 95–98% efficient at full load. The small losses in the drive are far outweighed by the process improvements and motor energy savings they enable. It's worth noting that running a motor on a VFD does induce some additional heating in the motor (due to the non-sinusoidal waveform), but most standard induction motors are now designed as “inverter-ready” with insulation that can handle the voltage pulses. When applications involve long cable runs, output filters (dV/dt filters or sine wave filters) can be added to further protect motor insulation – Yaskawa and others offer these as accessories. Overall, a properly applied VFD system is efficient, robust, and compliant with modern electrical standards. It will save energy, reduce mechanical and electrical stress, and provide a new level of controllability for motor-driven equipment.

Comparing Major VFD Manufacturers

While Yaskawa is a top player, it's important to recognize that the VFD market includes several other leading manufacturers, each with broad product offerings and particular strengths. ABB, for example, is another global leader in drives. ABB's standard low-voltage AC drive family (such as the ACS580 and ACS880 series) covers power ratings from around 0.75 HP up to 1700 HP in single-drive configurations – similar in span to Yaskawa's lineup. ABB drives are known for features like the previously mentioned Direct Torque Control, which provides extremely precise motor control without encoders. ABB also emphasizes ease of use (graphical assistant panels, built-in wizards) and offers many specialized variants, including regenerative drives and ultra-low-harmonic versions for applications with stringent power quality needs. In terms of market presence, ABB and Yaskawa are often considered neck-and-neck globally, and both brands have a reputation for high quality in industrial environments.

Hitachi is another established manufacturer of VFDs, though their drive line is somewhat more focused on small to mid-size applications. Hitachi's AC drives range from about 1/4 HP up to 600 HP at the top end. They produce compact sensorless vector drives (e.g., the WJ200 series) and heavy-duty models (like the SJ series) that are popular for general industrial use. Hitachi VFDs are often praised for their reliability and value – marketing materials highlight their "unbeatable performance, reliability, and flexibility," as well as energy-saving design to reduce power consumption in fans, pumps, and other equipment. In practice, Hitachi units provide much of the same functionality (network comms, vector control, etc.) as other brands in their class. The slightly lower upper power range (max 600 HP) suggests that Hitachi targets the majority of applications, while very high-power drives (in the thousands of HP) are left to the likes of ABB, Yaskawa, or specialist suppliers.

Eaton is a major drives player particularly in North America, with its PowerXL series of VFDs. The Eaton PowerXL drives (formerly known by names like Cutler-Hammer or IDT drives historically) now include the DG1 general-purpose series, which spans up to 1000 HP at 480 V and around 800 HP at 600 V. Eaton drives are designed with a heavy focus on user-friendly features and integration into broader electrical systems (given Eaton's background in switchgear and protection). For instance, all models of the DG1 come standard with embedded Ethernet/IP connectivity for easy integration. Eaton also markets an energy-optimizing function called Active Energy Control on their drives, which automatically reduces motor flux at lighter loads to improve efficiency and reduce heat. In terms of performance, Eaton's drives offer sensorless vector control and optional closed-loop control, comparable to others. The company's portfolio ranges from compact HVAC drives to larger MD series for high horsepower. Many OEMs and panel builders choose Eaton VFDs when they want a one-stop solution integrated with Eaton breakers, contactors, and panels.

Lenze (including the Lenze AC Tech brand in the US) provides a range of drives that have a strong following in certain industries, such as packaging, material handling, and plastics. Lenze's drives are often chosen for their simplicity and compact form factor. For example, the Lenze i500 series inverters cover about 0.33 HP up to 175 HP in a very streamlined, modular design. These drives emphasize easy scalability and commissioning – the i500 has plug-in option cards and a software tool that makes setup relatively straightforward. Lenze/AC Tech also produce the SMV series of washdown drives and the larger 8400 series for more power or higher performance needs. While Lenze's max power might not reach the highest of ABB or Yaskawa, they offer everything needed for small to mid-range systems and are known for a very user-friendly approach (often appealing to smaller machine builders or retrofit projects). One real-world example of Lenze drive usage is in precision manufacturing: a plastics extrusion plant implemented Lenze AC Tech drives on extruder and winder motors to improve speed regulation, which resulted in a 10% reduction in product scrap by achieving more consistent line speed and tighter thickness control. This underscores that even for challenging process control tasks, these drives can deliver excellent results.

It's worth noting that virtually all major VFD brands adhere to the same international standards and offer similar core capabilities – competition drives them to keep adding features and improving ease-of-use. Other notable manufacturers in the VFD space include Siemens, Schneider Electric (Altivar drives), Danfoss, Mitsubishi, and Rockwell Automation (Allen-Bradley PowerFlex drives). Each has its particular niches: for instance, Danfoss VLT drives are very popular in HVAC and refrigeration, Siemens has strong presence in high-power and regenerative drives (with their SINAMICS line), and Rockwell's PowerFlex is often chosen in the Americas for integration with Rockwell/Allen-Bradley control systems. In terms of capabilities, one could generalize that a VFD from any leading brand in 2025 will support: vector control, multiple motor types (induction, permanent magnet, even synchronous reluctance motors), network communications, functional safety options, low-harmonic solutions, and a range of enclosure and cooling options. Selecting the right drive is therefore often about matching the specific application requirements and considering practical factors like local support, compatibility with existing systems, and personal or organizational experience with a brand's programming style. For example, an engineer might choose ABB or Yaskawa for a high-performance industrial drive – both would work, but if they prefer ABB's DTC control or have ABB software tools on hand, that might tip the scale. Likewise, if an urgent replacement is needed and a certain brand isn't immediately available, an equivalent from another top brand can usually be substituted with confidence that it will perform equivalently in the system. This interchangeability is reflected in how distributors and service providers operate: companies like Precision Electric carry multiple major brands (Yaskawa, ABB, Eaton, Lenze, etc.) and will recommend a suitable alternative if it meets the customer's requirements and time frame.

Real-World Benefits and Applications

VFDs have become ubiquitous in a range of industries due to the compelling benefits they offer. A primary advantage – and one that often justifies the entire investment in drives – is energy savings. This is especially pronounced in variable torque applications like fans, pumps, and blowers, where the load's power draw drops dramatically with reduced speed. According to the affinity laws, the flow (of air, water, etc.) is roughly proportional to motor speed, but the power required is proportional to the cube of the speed. In practical terms, if you run a centrifugal fan at 50% of its maximum speed, it may consume only about 1/8 (12.5%) of the power compared to full speed. This nonlinear relationship means even modest speed reductions yield large energy cuts. By replacing throttling dampers or valves with speed control, VFDs eliminate the wasteful dissipation of excess energy. Studies and real-world implementations consistently report 20–60% energy reduction after adding VFDs in flow control systems. For example, an ABB analysis in marine applications showed that using VFDs on pumps and fans "can cut the energy consumption by as much as 60%" in those systems. In a municipal water treatment facility in Columbus, a retrofit project that replaced fixed-speed pumps with VFD-driven pumps achieved roughly a 30% reduction in energy usage for those pumps, translating to significant annual electricity savings for the city. Another case study by ABB documented that pairing a variable-speed drive (ACS580 series) with a wastewater pump yielded a 48% drop in yearly energy consumption, while also extending the pump's seal life by an estimated two years due to gentler operation. Similarly, in a Midwest grain handling facility, upgrading old across-the-line conveyor drives to modern Eaton PowerXL VFDs cut the conveyor motors' energy use by about 42%, which was enough to avoid a costly utility service upgrade that would otherwise have been needed to support the previous system's peak demand. These examples demonstrate that VFDs often pay for themselves through energy savings alone, especially on large motors running many hours per year. The return on investment can be very quick – sometimes under 1–2 years for heavy-duty pump/fan installations – and after that, the energy cost reduction goes straight to the bottom line.

Beyond energy efficiency, VFDs provide process improvements and equipment longevity benefits. Because a drive offers full speed adjustability, processes can be optimized in ways that were not possible with fixed-speed motors. Manufacturers in sectors like food & beverage, textiles, or plastics have used VFDs to improve product quality by dialing in ideal speeds and ramps for their machines. We mentioned the plastics extruder example where tighter speed control cut scrap by 10% – in that case, the precise PID control loop within the drive kept the line speed much steadier than the old manual method, resulting in more consistent product thickness and less waste. In another instance, a pulp and paper mill undertook a drives modernization: they replaced twenty aging VFDs (ABB ACS550 models) with newer-generation drives. After this upgrade, the mill observed that unplanned drive failures "plummeted by 76%" according to maintenance records, significantly improving uptime. The new drives' improved design and diagnostics meant fewer shutdowns, and the plant benefited from both increased production and lower emergency repair costs. This highlights a common scenario – when you replace decades-old drives or motor starters with modern VFDs, you inherently reset the clock on reliability and take advantage of the robust electronics and protective features of current designs. Moreover, many new drives have predictive maintenance functions (like tracking accumulated run hours, monitoring internal temperature, capacitor health, cooling fan run-time, etc.) which can alert users to service the drive or motor before a failure occurs. This kind of condition monitoring helps avoid unexpected downtime.

VFDs also markedly reduce mechanical wear on motors and driven machinery. By soft-starting, they avoid the high torque shocks of DOL (direct-on-line) starts that can crack shafts or shear keys. Conveyor belts, for example, greatly benefit from gentle acceleration – it prevents belt slipping and stretching. Pumps started with a VFD ramp up without pressure surges, protecting pipes and valves. Even stopping under controlled deceleration can prevent products from toppling or fluids from hammering. All of this translates to longer life for mechanical components and less maintenance. Motor bearings and couplings see less strain, and the motors run cooler on VFD at partial speed/load (reducing insulation stress). It's true that high-frequency voltage from a drive can introduce bearing currents in large motors (potentially causing EDM pitting in bearings over time), but mitigation techniques like 3-level inverters (as in Yaskawa G7) or simple shaft grounding brushes can address that. On balance, the consensus is that a properly applied VFD extends the lifespan of the overall motor-driven system.

Another benefit worth mentioning is the ability of some drives to provide braking and hold control. With optional dynamic braking resistors or regenerative units, drives can decelerate heavy loads quickly or hold a motor at zero speed, which is useful for cranes, hoists, elevators, and unwinders. In multi-motor coordinated systems, VFDs offer the ability to synchronize speeds or manage tension (for instance, multiple conveyors in a production line can be synchronized to avoid pileups, or a dancer-controlled winder can maintain constant tension on material). These advanced functions were once the realm of complex control systems, but now often come built into the drive's firmware logic.

In terms of industries, Yaskawa frequency drives (VFDs) and their counterparts are found virtually everywhere: HVAC systems (fans, blowers, chillers, cooling tower pumps), water/wastewater (booster pumps, aerators), manufacturing (conveyors, mixers, extruders, machine tools, robots), oil & gas (compressors, drills), renewables (wind turbine pitch and yaw drives), and many more. They are a cornerstone technology for achieving energy efficiency and precise motion control, both of which are high priorities in modern operations. Using drives, facilities not only save on energy costs but also reduce their carbon footprint – a significant factor as sustainability goals become integral. For example, large retail chains retrofitting HVAC drives have documented energy consumption drops of around 20–30%, translating to millions of kWh and dollars saved annually, plus sizable CO2 emission reductions. Utilities and governments often incentivize VFD installations through rebates because of these clear energy and demand-side management benefits.

Conclusion and Future Trends

Finally, from a maintenance and operations perspective, having VFDs can improve overall system flexibility. Speed can be adjusted on the fly to adapt to process changes (no need for mechanical gearbox changes or pulley swaps). Many drives support remote monitoring – either through a plant network or even cloud-based systems – so technicians can observe performance and get alerts if something is off nominal. And in the event of a problem with a motor or pump, the drive's fault logs provide a starting point for troubleshooting (e.g., indicating if there was an overcurrent trip, undervoltage event, etc.). The value of this information cannot be overstated when trying to reduce downtime. There's also an emerging trend of digital twins and IIoT (Industrial Internet of Things) connectivity: drives can feed data into analytic platforms to predict failures or optimize processes in real time.

To sum up, Yaskawa frequency drives exemplify the many advantages of modern VFD technology – energy savings, process optimization, extended equipment life, and high reliability – and they do so across a vast array of applications. Yaskawa's products, alongside those of other major manufacturers like ABB, Hitachi, Eaton, and Lenze, have become indispensable tools in contemporary engineering. When properly applied, a VFD is often a "win-win" solution: it saves money by trimming energy and maintenance costs, while also giving engineers superior control over their systems. As industry moves further toward automation, efficiency, and smart factories, the role of VFDs is only becoming more central. Yaskawa and its competitors continue to evolve drive technology (with trends toward higher power density, better connectivity, and smarter control algorithms), but the fundamental benefits that frequency drives deliver will remain a cornerstone of industrial and commercial systems for the foreseeable future.

References

• Yaskawa America – Industrial AC Drives Product Overview – Yaskawa's official catalog of industrial AC VFD products, listing power ranges (1/8–2250 HP) and highlighting the latest technological advancements in motor speed control.
• Yaskawa America – GA700 Drive Standards Compliance Manual – Technical documentation showing Yaskawa GA700 series compliance with CE (IEC/EN 61800-5-1 for safety, EN 61800-3 for EMC) and functional safety ratings up to SIL3, PL e.
• Precision Electric (Craig Chamberlin) – "Yaskawa VFD Drives" – Blog article (2014) describing features of Yaskawa drives, such as built-in DC reactors (3% impedance standard on ≥30 HP) and multi-pulse harmonic mitigation options (12-pulse, 18-pulse) for IEEE 519 compliance.
• Precision Electric (Craig Chamberlin) – "Yaskawa Variable Frequency Drives" – Blog article (2013) providing an overview of Yaskawa as a company (the world's largest AC drive manufacturer) and highlights of specific models like A1000 (closed-loop vector up to 1000 HP) and G7 (3-level inverter for long motor lead applications).
• Control Global – Yaskawa Ships 10 Million Drives – Industry news (2008) noting Yaskawa as the first to ship 10 million VFDs, with historical innovations (first transistor inverter in 1974, first IGBT low-noise inverter in the 1980s) and an exceptional field failure rate of 0.0062%.
• ABB – ACS880 Catalog: ABB Industrial Drives 0.75 to 1700 HP – Product catalog for ABB's ACS880 series drives, demonstrating the wide power range (up to 1700 hp / 1300 kW) and featuring ABB's Direct Torque Control (DTC) for precise motor control.
• Control Components Inc. – Hitachi Variable Frequency Drives – Manufacturer/distributor page for Hitachi drives, indicating Hitachi's drive range from 1/4 HP through 600 HP and their focus on advanced features and eco-friendly, power-saving operation.
• Seagate Controls – Eaton PowerXL DG1 VFD Overview – Product page listing the Eaton PowerXL DG1 drive family capabilities, including supported voltages and horsepowers (e.g. up to 1000 HP on 480 V) and standard features like built-in EtherNet/IP and Active Energy Control.
• Lenze Americas – i500 Inverter Series Brochure – Brochure for Lenze's i500 series drives, noting the power range (0.33 to 175 HP or 0.25–130 kW) and emphasizing the series' scalability, compact size, and suitability for various applications.
• Eaton – Soft Starter vs VFD Application Note – Technical note explaining how VFDs reduce inrush current and mechanical stress by ramping motor speed, and describing the affinity law relationship where reducing speed dramatically cuts power demand (e.g. half speed → one-eighth power).
• ABB White Paper – Using VFDs to Save Energy (ABB Marine) – White paper highlighting energy efficiency improvements from VFDs, stating that in pump and fan applications, variable frequency drives can reduce energy consumption by up to 60% by avoiding throttling losses.
• Precision Electric – Yaskawa VFD Overview & Case Studies (2025) – Comprehensive overview document with comparisons and real-world case studies: e.g. 30% energy savings at a Columbus water plant, 48% savings and longer seal life with an ABB drive on a pump, 42% conveyor energy reduction with Eaton drives, 76% fewer drive failures after upgrades in a paper mill, and a 10% scrap reduction in a plastics line using Lenze drives.

External Links:

• How to choose between a soft starter and a variable frequency drive
• Yaskawa Variable Frequency Drives | VFDs | Precision Electric, Inc
• Industrial AC Drives - Yaskawa
• Yaskawa says it is the first manufacturer to ship 10 million VFDs | Control Global
• Yaskawa VFD Drives
• ABB industrial drives - ACS880, single drives, 0.75 to 1700 hp (0.55 to 1300 kW), Catalog
• Eaton PowerXL DG1 AC Drives | Buy Online at Low Cost
• YASKAWA AC Drive GA700 High Performance General Applications Drive Standards Compliance
• Hitachi Inverters Distributor | AC Variable Frequency Drives | Control Componen
• [PDF] Brochure i500 series frequency inverters - Lenze
• Yaskawa Variable Frequency Drive (VFD) – Overview, Comparisons & Services
• Using Variable Frequency Drives (VFD) to save energy and reduce emissions in newbuilds and existing ships