Field-Oriented Control Systems Shape Future Designs of Cordless Power Tools

In recent times, building supply stores across the globe have seen some sweeping changes, especially in the garden appliance and power tool sections, for products such as saws, drills, lawnmowers, and vacuum cleaners among others.

The first major change which was introduced to the global power tools market was the cordless devices that were powered through portable batteries. This was followed by the inclusion of technological innovations such as brushless direct current motors and full-bridge drivers for brushed motors, which were aimed towards extending battery life and adopting very complex schemes for equipment control that integrated sensors with power drivers and controllers to manage switching sequences seamlessly.

Furthermore, recent innovations even provide power tools to be tracked wirelessly through a form of low energy Bluetooth connectivity, providing end-users with easier tracking of inventory and deterring theft of valuable devices. In the latest development, manufacturers have made revolutionary changes in the core design of microcontrollers and motor-control algorithms, which are increasingly being incorporated into various power tool designs.

Field Oriented Control Changes Brushless Direct Current Control Methods

Unlike brushed motors that make use of permanent-magnet stators, mechanical commutation, and wound armature, the brushless direct current (BLDC) stators comprise windings that are sequentially powered to generate a rotating electro-magnetic field. The BLDC rotor follows the movement of this field acting as a permanent magnet. Standard configurations comprise 6 symmetrical coils that are arranged into 3 distinct phases at intervals of 120-degrees.

The BLDC system is essential for switching electrical currents to the windings in a sequential manner for maintaining the movement of the rotor, which can be achieved with either trapezoidal commutation, or sinusoidal control, or the newest method which makes use of electro-magnetic field oriented control (FOC).

The FOC method was initially considered to be unsuitable for low cost applications, owing to costly sensors and high power consumption. However, improvements in the field have generated optimized opportunities for inclusion in different types of power tools.

FOC Provides Unique Advantages for Power Tool Designs

 Compared to other methods of commutation, FOC offers users with a number of exclusive advantages such as superlative dynamic behavior, improved operational efficacy, complete motor torque capabilities even at low speeds, decoupled flux and torque control, four quadrant operations, and overload capabilities for short periods of time.

The system offers optimal torque control through achieving constant phase lag at 90 degrees to the stator, under different loads, while simultaneously calculating rotor flux angles several times each second to optimally modulate the current, in comparison to the limited commutation options offered by conventional methods.

While FOC had many potential applications, it was largely considered to be impractical owing to the lack of accuracy in simple power tool devices to make use of the system in the right way. However, recently manufacturers have claimed to have developed a sensor-less version to circumvent this issue.

InstaSPIN Eliminates Complexities in Development of FOC Technologies

FOC systems are especially effective when used in power tools that integrate centrifugal mechanisms, scientific instrumentation, or high speed blowers or compressors, or those that are used in heat sensitive or portable applications. However, the complexity of developing algorithms to meet the requirements of every unique motor is a major challenge for designers.

InstaSPIN is a new FOC algorithm building tool by U.S. based Texas Instruments that, simplifies this challenge significantly, by providing ready to use blocks of algorithm functions that can be used by skilled developers to easily optimize power tool motor performance over a wide variety of operational conditions.

Torque/velocity control or position/velocity motion control is performed through automated identification of the type of motor being used, and the tuning of the torque controller without needing mechanical rotor sensors.

FOC Finds Extensive Use in Electric Drives in Power Tools

Field-oriented control (FOC) varies significantly from ordinary control mechanisms for electric motors by enabling enhanced precision in control capabilities on the basis of speed and torque. These aspects are highly relevant for modern electric motors that are being used in the numerous power tools and their applications.

Field of Control mechanisms can be utilized for durable, very reliable and supremely energy-efficient designs for motors in various power tool segments. Motors can be utilized at their optimal range of torque and speed in any situation, while simultaneously offering users very accurate and and fast regulation of motor speeds, which is very crucial for uses that are commonly impacted by dynamic load changes, in devices such as ventilators or pumps.

FOC also enables significant reductions in fluctuating torque, which leads to a much smoother rotation of motor components. As a result devices that make use of FOC emit lower levels of noise, which is especially important for electrically powered power tools that normally do not have a loud motor assembly. In addition, the smoother operations of such motors also noticeably reduces the wear and tear of the devices bearings, resulting in greatly enhanced robustness and reliability, enhancing the demand in the power tools market.

The field-oriented control method has been viewed by device designers as a very desirable combination to improve on performance features. However, the system was considered too expensive for low cost applications. However, with the introduction of Piccolo microcontrollers, and the internal InstaSPIN FOC module, FOC is finding widespread application in power tools.

On the other hand, the usage of FOC in power tools also has a number of disadvantages. The most impactful of these being the costs associated with the implementation of rotor sensor components, which is implemented either mechanically or in the form of a complex software, which so far have been considered to be the most unreliable part of such power tools. The unreliability of these components results in increasing costs or higher error rates, which is why the InstaSPIN development is of such importance.

Searching for new insights on the global power tools industry? For reliable and actionable forecast information on the terms of location and product, visit Future Market Insightsrecent study on the global power tools market. This report also talks about factors such as the competitive environment, key market share holders, industry hierarchy, and popular strategies.

About Sandali 225 Articles
A former journalist, Sandali is a content marketer with over 5 years of writing experience, across various industries including Food Innovation, Healthcare, and IoT and Technology. Sandali has been weaving corporate stories for organizations through different forms of impactful marketing content. Her key aim is to strategically align well-crafted narratives with business objectives, translating into a powerful communications platform for the company.