Foc motor control bldc

This platform has been designed to help you to achieve your business goals. We will provide end-to-end support from prototyping to production-grade projects related to the Electric Vehicle EV product development.

This platform can be integrated with our ready-to-deploy and reusable software stacks UDS, J, OBD and othersas per your requirements. Vinu is always ready to take on new challenges. An avid supporter of innovation and learning, Vinu is also associated with projects that have led to disruptive innovations at Embitel. A person with calm and composed demeanor, Aneesh always leads from the front.

This Base Software can be customized for integration with your Application layer, helping you save substantial development time and cost approximately months. As an additional value-add, a critical software module of the Application layer, which is Field Oriented Control FOC algorithmhas also been implemented and can be readily integrated with your system.

For an organization, that plans to develop a prototype of motor control ECU for electric vehicles, this configurable platform is an ideal solution. The design and development of this motor controller for electric vehicle, adheres to the guidelines of the ISO Standard for Functional Safety in Automotive.

We have a dedicated team of Functional Safety Consultants and Engineers. This team has in-depth knowledge of the ISO standard and has also delivered successful Consulting and Implementation projects for our Global Automotive Customers.

We will also extend all the necessary support; in order to help you achieved the compliance for the required ASIL value, for your EV project. How do you tune or optimize your FOC algorithm before testing it on the bench? In order to minimize the bench testing and tuning efforts in the FOC algorithm, we tune it using Plant Model simulation.

On which hardware platform have you designed this ECU solution? Can you provide support for development on other Microcontroller Platforms? In order to help you develop the system on a different microcontroller, we will provide support for the necessary customization of the low-level drivers, of our base software module. The existing Hardware Abstraction Layer designed by our team can be reused completely. For all the applications in which these motors are integrated in an Electric Vehicle, our motor control system can be leveraged to demonstrate your PoC.

One of the most widely implemented use-case is the Drivetrain of Electric Vehicles both two-wheelers and cars.

foc motor control bldc

We have implemented certain diagnostics and fault-handling capabilities in the motor control system ECU. Following algorithms for diagnostics are implemented in the application layer:.

We have a team of hardware engineers who can take care of the implementation of the application, HAL and LLD in the vehicle phase. We can carry out this activity on-site or support from our premise. Please share the skill-set of the engineers involved in the development of this solution Ans. The skill set of Engineers who have developed the motor control system is as follows:.

Work with us People at Embitel Life at Embitel. This website doesn't store cookies. Enjoy the experience, without worrying about your data! Great, thanks!The AMT is ideal for ceiling fans, pedestal fans, bathroom exhaust fans and home appliance fans and pumps. A field-oriented control FOC algorithm is fully integrated to achieve the best efficiency and acoustic noise performance.

The device optimizes the motor startup performance in a stationary condition, a windmill condition, and even in a reverse windmill condition. Closed-loop speed control is optional, and RPM-to-clock frequency ratio is programmable. A simple I2C interface is provided for setting motor-rated voltage, rated current, rated speed, resistance, and startup profiles. Check out our device offerings and packages across all of our product families in this PDF selection guide. Current Sensing.

Switches and Latches. Hall Effect Latches Bipolar Switches. Dual Hall-Effect Latches. Three Wire Hall Effect Switches. Two Wire Hall Effect Switches. Micropower Switches Latches. Special Purpose Devices. Linear and Angular Position. Angular Position Sensor ICs. Linear Position Sensor ICs.

How the Brushless motors are made (BLDC)

Magnetic Speed. Camshaft Sensor ICs. Crankshaft Sensor ICs. Transmission Sensor ICs. Wheel Speed Sensor ICs. Multiple Output Regulators.So what these people are calling their commutations are based on the diagram of the motor current output.

Since there is no high current fast switching within FOC mode, there is simply no high pitch sound you usually hear from BLDC commutation. Logically since FOC is modulating the phases, it maximizes the torque output at any point due to that the ABC phase are always charged and each of them are using only as much as what do they require for each rotor position within the motor.

Logically since sinusoidal control are creating smooth wave form instead of spikes like BLDC and Trapezoidal, the peak point of each amplitude is less than BLDC mode and or trapezoidal mode.

foc motor control bldc

Therefore it has slightly less top speed. In general this is what I understand as a beginner. I might be wrong on certain things, but the general explanation in performance factors and diagrams are surely why they are named after each other. Except one thing is bugging me. Does that seem right? Yea, pretty much. BLDC is simply switching on and off classic 6-step commutationin FOC the Mosfets are also switching on and off but the algorithm behind is different.

The principle is similar to PWM but with angles instead of voltages. So now the angle can be adjusted but the length of the vector still needs to be modified aswell. I wrote that there are 8 switching possibilities of the Mosfets, on two of them the motor windings are shorted, so there is no voltage drop on the windings. Of course the math behind is much more complex than in BLDC. My diploma thesis was about that stuff. You can read all this on wikipedia, I just tried to shorten it and to explain it in a more practical way.

Since it now switches at a much higher frequency by my undersatnding than bldc? The FOC algorithm uses Park and Clarke transformations… some years ago I thought Laplace and Z- transformations were difficult but suddenly this hits you lol.

Field Oriented Control

Jinra Yes, the high switching frequency is needed to get greater efficiency and a more quiet motor. The switching frequencies in FOC are usually around kHz, interestingly, above around 60 kHz the switching losses caused are bigger than the gained advantages because increased switching frequency decreases drive efficiency. But this usually very dependent on the system motor inductance etc.

Usually at least what I always did was selecting it as high as possible to reduce noise in the audible frequency range, so usually between 14 and 20 kHz but he BLDC drivers limit you anyway…. In contrast, trapezoidal generates some strange shaped current waveforms.

In theory, a lot of people draw them like modified square waves but in practice I usually find that they look more like curly "w"s. Almost every motor controller will use PWM. Sinusoidal and FOC use PWM to generate their roughly sinusoidal voltage waveforms which in turn generate roughly sinusoidal current waveforms.

Any 4 of these sensor methods can be used with trapezoidal, sinusoidal, or FOC!!! In addition to rotor angle sensing, sinusoidal and FOC also require phase current sensors. These are usually pretty straightforward and inexpensive to include on a motor controller. Stick with trapezoidal at low speeds if you have hall sensors.

Each of these control schemes can use sensorless, hall sensor, encoder, or resolvers methods to detect rotor position, but in practice sinusoidal and FOC are pretty crap without an encoder or resolver.Performance Motion Devices, Inc.

Westford, MA P: Of these, BLDC and step motors are 'multi-phase', meaning they require some type of external coil excitation to keep the motor moving. This deep dive article will examine the most popular techniques for multi-phase motor control, with an eye toward determining what control techniques, including field-oriented control FOCwork best for a given application in positioning and high-speed spinning applications.

For Brushless DC motors, magnetic fields are generated by magnets mounted directly on the rotor and by coils in the stator. The stator windings generally come in a 3-phase configuration and are arranged to be electrical degrees apart from each other. It is the sum of the force generated by these three phases that will ultimately generate useable motor rotation.

Depending on how the individual magnetic coils are phased, they can interact to create force that does not generate rotational torque, or they can create force which does drive rotation. These two different kinds of force are known as quadrature Q and direct Dwith the useful quadrature forces not to be confused with quadrature encoding scheme for position feedback devices running perpendicular to the pole axis of the rotor, and the non-torque generating direct forces running parallel to the rotor's pole axis Fig.

The trick to generating rotation is to maximize Q quadrature while minimizing D direct torque generation. If the rotor angle is measured using a Hall sensor or position encoder, the direction of the magnetic field from the rotor is known. Six step commutation is a simple technique that reads Hall sensors and excites the coils in a specific sequence.

The downside to this technique is that for many motors it gives up some efficiency and is not as smooth as more advanced techniques. This is because the output control signal for each coil changes abruptly when a new Hall state is read, which occurs every 60 electrical degrees. That kind of performance is fine for simple spinning applications, or applications where the motor is geared way down.

But for systems that need smoother motion and higher performance, two advanced techniques : sinusoidal control and field oriented control FOCprovide a jump in performance.

foc motor control bldc

It resembles sinusoidal commutation, but adds a major mathematical twist. Figure 2: Sinusoidal Commutation. Figure 3: Field Oriented Control. Figure 3 shows control schemes for both sinusoidal commutation and field oriented control.

In the sinusoidal control approach, the torque command is 'vectorized' through a sinusoidal lookup table, thereby developing a separate command for each winding of the motor. As the rotor advances, the lookup angle advances in kind. Once the vectorized phase command is generated, it is passed on to a current loop, one for each winding, which attempts to keeps the actual winding current at the desired current value.

An important characteristic of this approach is that as the frequency of motor rotation increases, so does the challenge of maintaining the desired current.

This is because the current loop is affected by the rotation frequency. Lag in the current loop, insignificant at low rotation speeds, generates increasing amounts of D unwanted torque at higher rotation speeds, resulting in a reduction of available torque. The control scheme for field oriented control FOC differs in that the current loop occurs de-referenced from the motor's rotation.

That is, independent of the motor's rotation. The Q torque loop is driven with the user's desired torque from the servo controller. The D loop is driven with an input command of zero, so as to minimize the unwanted direct torque component. The trick to making all of this work is math-intensive transform operations that convert the vectorized phase angle to, and from, the de-referenced D and Q reference frame.In Application ExamplesOur productsTutorials. Students, enthusiasts, or professional engineers can now enjoy our five-part MOOC Massive Open Online Courses to help them master this challenging subject matter.

One of our core competency is the optimization of controllers and power devices responsible for driving motors. Moreover, we just launched yesterday a whole new series of microcontrollers, the STM32G4that integrates new mathematical units and a plethora of analog peripheralsmaking it an exceptional MCU for motor control, among other applications. Our Motor Control MOOC is highly extensive and will benefit a wide range of users as it starts with the fundamentals on brushless DC BLDC motors and goes all the way to troubleshooting a design and the intricacies of field-oriented control.

The first part gives an excellent theoretical overview to ensure students have a strong understanding of the vocabulary and concepts at the heart of motor control.

foc motor control bldc

The course also explains why these measurements are crucial once engineers start developing their applications, ensuring that they get a relatable and real-world experience. It even offers a spreadsheet to help them transition to our motor control SDK.

The lectures start by showing students how to get started, and by the end of the coursework, they will be able to use our FOC library. The lecture below goes into the firmware architecture and APIs as well as what the commands look like once developers call them in their code.

Once students have a strong understanding of motor control applications, Motor Control Part 3 looks into fine-tuning and troubleshooting systems.

It delves into PI regulators and the most common runtime issues. The videos are generally short, and in the example below, teachers go over the steps necessary to diagnose errors and explain in detail the typical solutions available. Students tend to overlook Motor Control Part 4 and vastly underestimate its importance, but choosing the wrong component can break a design, cause massive delays, and potentially harm end users.

Additionally, the knowledge and experience in this course will serve engineers because the point is to help them understand how to read data sheets and look out for what matters. For instance, the ST Op-amp App is a great time saver. The coursework reviews some of the basics to reinforce essential concepts and build a strong foundation to help engineers implement validation processes and optimize their applications.

For instance, the video below looks at braking strategies and the best way to dissipate the kinetic energy to stop operations without damaging the system. Depending on the application, engineers can use a brake resistor or a DC vector, among others.

AMT49406: Code-Free FOC Sensorless BLDC Motor Controller

In Internet of Things. In Application Examples. Motor Control Part 3: Troubleshooting and Fine-tuning Once students have a strong understanding of motor control applications, Motor Control Part 3 looks into fine-tuning and troubleshooting systems.

Motor Control Part 4: Selecting the Right Components Students tend to overlook Motor Control Part 4 and vastly underestimate its importance, but choosing the wrong component can break a design, cause massive delays, and potentially harm end users.Brushless DC motor BLDC replaces the mechanical commutator with electronic commutator, just because of the electronic commutator, the BLDC motor needs a controller to drive the circuit.

The commutation circuit of BLDC motor consists of two indispensable parts: drive and control. Particularly, the two parts are integrated into a single ASIC for low power circuit. What are the advantages and disadvantages of these 3 control methods? In this control method, the phase current waveform of the motor approaches the square wave, so it is called square-wave control. Advantage of square-wave control include: simple control algorithm, low hardware cost, and higher motor speed can be obtained by using ordinary controller.

Disadvantage of square-wave control include: large torque ripple, a certain current noise, efficiency is not up to the maximum. Square-wave control is suitable for occasions where motor rotation performance is not very high.

Sine wave control Sine wave control uses the SVPWM wave and outputs the three-phase sine-wave voltage, corresponding current is sinusoidal current. Obviously, sine wave control has smaller torque ripple and less current harmonics than the square-wave control, its control is more "exquisite".

FOC control Sine wave control realizes the control of voltage vector and indirectly realizes the current control, but it can not control the direction of current. Advantages of FOC control include: small torque ripple, high efficiency, low noise and fast dynamic response. Due to its distinct advantages, FOC control has gradually replaced the traditional control mode in many applications and won great favor in motion control field.

My Account Register Log in Wishlist 0. Back Servo Motors. Back AC Servo Motors. Back AC Gear Motors. Back Variable Frequency Drives. Back Transformers. Back Isolation Transformers. Back Contactors. Back DC Contactors.Permanent magnet synchronous motors like BLDC 3-phase or stepper motors 2-phase are used in various applications and can be controlled in different ways.

Field oriented control FOC is one way to do so. It uses current control to control the torque of 3-phase motors and stepper motors with high accuracy and bandwidth. FOC can be implemented in either hardware or software. Applying current in phase to the magnetic field does not generate torque, but orthogonal applied current does.

FOC is simply a way of dealing with this issue and it is therefore in need for actual current and rotor position information. The field oriented control structure is based on two simple mathematical transformations — Clarke and Park — of the actual phase currents, transforming the actual phase currents from stator-fixed to field-synchronous coordinate systems. The resulting coordinate system has only two dimensions. These two dimensions are orthogonal components that can be visualized as a vector, which is why FOC is also known as vector control.

With FOC, two PI current controllers can be used to control both components of the motor current vector separately.

The transformations are based on the actual rotor angle, which has to be acquired by position sensors like Hall sensors or encoders. This magnetic flux is mainly generated by the rotor, which is why its target value is usually zero.

Servo control adds a speed- and a position controller to this control structure to make it fully functional for positioning applications. All controllers require proper feedback to work at high dynamics and to compensate for unknown load forces. For the current controllers, this means that the coil currents need to be measured. Position can be measured with encoders or roughly with Hall sensors. As velocity sensors are not common, the velocity of the motor is often computed by differentiation of the position signal.

The power stage of the drive is used to convert electrical power from the power supply to generate the required motor currents. Pulse width modulated gate signals allow the power stage to display certain voltages — which is why the servo controller needs a pulse width modulation PWM block.

Control Methods of BLDC Motor

It allows the servo controller to transform voltage needs from the current controller into actual voltage requests at the power stage. The so-called space vector modulation is often used to generate enhanced PWM signals. It also enables a higher voltage utilization when compared to normal modulation, while keeping the cost basically the same in the usual applications. FOC, or vector control was first developed in the s in Germany. The control structure gained currency with the development and spreading of microprocessors in industrial applications and became a standard technology during the s.

Actual research points in the direction of sensor reduction and enhancement of dynamics. With a field-oriented current control with space vector PWM: velocity control loop, and position control loop and ramp controllers, the software builds a complete servo controller stack.

As all control functions are implemented in hardware, embedding all necessary control loops in rugged, reliable state machines, you have a free choice of processor.

Integrated ADCs, position sensor interfaces, and position interpolators enable a fully functional servo controller for a wide range of servo applications such as robotics, pick and place machines, factory automation, e-mobility, lab automation, and blowers. Home Technology Std. Technologies Field Oriented Control. Field Oriented Control.

Field oriented control FOC is a powerful control strategy to control torque of 3-phase AC machines and stepper motors with high accuracy and bandwidth.

It can be implemented in either hardware or software. FOC motor control. What is FOC? Field Oriented Control And why you should use it! Products for Field Oriented Control. More on Motion Control. We live in a physical world. Whenever we need an object on the right time at the right place, we need motion control.


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