The European Union (EU) is comprised of twenty-seven member countries representing more than 500 million citizens and 33% percent of the world's gross domestic product. As the executive branch of the EU, the European Commission (EC) is responsible for proposing legislative acts or directives, regarding commerce, transit, and even energy efficiency. With the union's roots in technical innovation, the EC is well-recognized throughout the world for its development of progressive, energy-saving directives. Many countries, including China and the U.S., use the EC's directives as templates for their own energy policies.

Although these directives often appear as unnecessary obstacles during product design, they are the catalysts that promote the innovation of eco-friendly products that lead to a healthy environment and conserve natural resources. Throughout the world, governments strive to enact legislation that will reduce greenhouse gas emissions, decrease the need for building more power generation facilities, and ultimately keep electrical power affordable for consumers and industry. Mandating residential, commercial, and industrial equipment to perform at higher efficiencies is the most cost-effective and timely path to achieve these goals.

In an attempt to make consumers and businesses more cognizant of the importance of energy efficiency in common appliances, EC Directive 92/75/EEC was developed. This directive defines a standardized label format which includes efficiency data and anticipated annual energy usage. These labels openly disclose the necessary information to enable the consumer to make informed purchases considering both initial purchase price and estimated cost of ownership due to energy consumption. The voluntary Energy Star program allows efficient appliances to carry the Energy Star logo. These products have been demonstrated to use between 10 and 66 percent less energy and/or water than standard models while maintaining the desired features and reliability. Energy Star appliances can save 20 to 30 percent in annual energy costs. Energy-saving potential
The energy-saving potential of this legislation has lead to the development of supplemental directives and amendments which mandate minimum efficiency requirements for various types of residential and commercial equipment. Efficiency labeling for refrigerators, freezers, washing machines, dryers, dishwashers, ovens, water heaters, air-conditioners, and lighting sources is required. Labeling remains optional for televisions, computers, printers, and other small devices. The figure below illustrates the distribution of annual electricity consumption by U.S. households. Electric motors are responsible for 20, 50, and nearly 75% of the electricity used in the U.S., China, and India respectively. Worldwide, approximately 57% of the total energy produced is used to power electric motors.

Click on image to enlarge.

In a typical modernized country, a household will consume about 11,000 kilowatt-hours (kWh) of electricity per year at a cost of nearly 1,000 euros. A significant amount of this energy is consumed operating electric motors in clothes washers, air-conditioners, heating units, ceiling fans, etc. In the U.S., this accounts for nearly 100 Terawatt-hours of electricity and costs consumers $8B euros annually. At this scale, a 5% improvement in efficiency represents a remarkable energy savings of 5 billion kWh, saving consumers $425M euros per year. Commercial and industrial savings are equally impressive.

For decades, the alternating current induction motor (ACIM) has been the motor of choice for household appliances and industrial applications due to its traditionally inexpensive materials, minimal maintenance, and excellent reliability. It is estimated that 90% of the installed motors worldwide are induction motors. Over the past few years, the cost of copper and steel has considerably increased while new technologies have led to the availability of less expensive magnets. This trend has given new life to permanent-magnet-based motors such as the brushless DC (BLDC), permanent magnet synchronous motor (PMSM), and many others. The development of innovative and sophisticated control systems allows BLDC, PMSM, and even ACIM motors to operate at their maximum potential. Motor efficiency factors
Electric motor efficiency is affected by a number of factors including supply voltage, load level, control and modulation scheme, duty cycle, and even temperature. Most ACIMs are designed to perform at peak efficiencies of approximately 70% when operated from 75-90% of their rated load. At light loads, ACIM efficiency decreases significantly. It is estimated that 44% of motors used in commercial and industrial applications are operating at less than 40% of their rated load. For applications that routinely use these motors at a fraction of their rated load, investment in high-efficiency controls and motors can pay-off in as little as two years.

State-of-the-art electronic motor controls employ advanced techniques such as adaptive phase timing, stator/rotor field modeling, bus compensation, and power factor correction to coax every last percent of efficiency out of the connected motor. Peak efficiency typically comes at a cost of decreased peak torque, poor speed range, or excessive control circuitry losses. Modern electronic controls that allow motors to operate over a wide range of speed and load combinations are called variable-speed drives (VSDs). Intelligent VSDs are capable of automatically adapting to an application's needs by providing efficient operation, peak speed, and peak torque as needed. VSDs using the latest semiconductor technologies can perform at double the efficiency of some motor-only systems.

Power semiconductor companies have invested countless millions of dollars and years in the development of components and technologies that allow appliance and machine designers to implement high-efficiency electronic motor controls with a minimum R&D expense and significantly decreased time to market. Fairchild Semiconductor's Smart Power Module (SPM) technology integrates the bulk of the power components required in every motor-control design into a small, eco-design-friendly package. These highly-integrated solutions include full, 3-phase MOSFET or IGBT power bridges, high-voltage gate drivers, bootstrap diodes, thermal protection, and over-current detection circuitry. Power Factor Correction (PFC) modules are also available using Fairchild's SPM technology.

Designed specifically for ACIM, BLDC, PMSM, and switch-reluctance (SR) motors, SPMs support motors from 10W to 7.5kW. Using the latest Field-Stop technologies, these modules are optimized for reduced EMI and low switching/conduction losses. These cost-effective modules allow appliance and system designers to expediently incorporate the latest efficiency-improving technologies into their motion-control products. The figure below shows the simplified diagram of a three-phase drive based on SPM technology. Smart Power Modules are definitely engineering-friendly!

Click on image to enlarge.

Although VSDs can simplify mechanical systems and enhance system reliability and long-term efficiency, some characteristics of these traditional drives prevented them from being considered as effective solutions in fixed-speed applications in the past. Advanced control algorithms and state-of-the-art electronics are now able to overcome most of these concerns. For example, Field-Oriented Control (FOC) algorithms allow an ACIM to perform in applications that previously required brush DC motors. This is due to their improved response to dynamic changes in load and improved torque at low speeds. Only recently, has the cost of an ACIM and control begun to approach that of a brush DC motor and control. These trends will continue to introduce new motor topologies into mainstream applications that were previously served by brush DC motors and drives.

With every passing year, countless irresistible electronic gadgets appear on the market and find their way into homes around the globe. The worldwide demand for electricity is growing at an unprecedented and alarming rate. New technologies must be developed and integrated into these gadgets to ensure that future energy supply meets our demands at a cost which is not prohibitive to the average consumer. To date, only a fraction of the existing high-efficiency motor and control technologies are found in a typical appliance or industrial system. Companies, like Fairchild Semiconductor, are focusing on providing innovative, efficient solutions that are engineering-friendly.