DC motors, every brushless motor requires a âdriveâ to supply commutated current to the motor windings .... This condition is like a reverse bus voltage is applied to the winding and the current decays at a fast rate. ... In the above equation, a
the BLDC motors. In BLDC motor, the commutation of a BLDC motor is controlled electronically. To rotate the BLDC motor the stator windings should be energized in a sequence. It is important to know the ... P controller, PI controller, PD controller a
cancel each other. This strategy was first suggested by. Ackermann . Finite element simulations of this technique yield a multiplicity of zero-cogging solutions, as shown in Figure 5. 0. 2. 4. 6. 8. 10. 12. 14. 16. 18. 20. 0. 2. 4. 6. 8. 10. 12. 1
Jul 19, 2010 - BLDC motors, also called Permanent Magnet DC Synchronous motors, are one of the motor types ... The brushless DC motor is a synchronous electric motor that, from a modelling perspective, looks ..... intervals and aligned properly with
but any reference to ATmega48 in this document also applies to ATmega88/168. 8-bit. Microcontrollers. Application Note. Rev. 8012A-AVR-10/05 ...
synchronous motor. Keywords: Operational; characteristics; bldcm. 1. Introduction. Brushless dc motors are rapidly gaining popularity in the appliance, ... Three-phase brushless dc motors are operated by energizing two of its three phase windings at
technique used in a permanent magnet brushless sensorless drive. Various existing ... (2), where L is self inductance, Î» represents flux linkage due to permanent magnet attached to the rotor which .....  C. Uang, Z. Ho, P. Wang and S. Liu, Senso
In this chapter, the basic structures, drive circuits, fundamental principles, ... Fig.2 Brushless dc motor = Permanent magnet ac motor + Electronic commutator.
hybrid bicycle powered by re-chargeable lead acid batteries. The aim of this paper is to design an electronic control unit for brushless DC (BLDC) motors in an ...
shape, voltage and current limits, an arbitrary phase winding connection, a simple eddy current loss model, and a trade- off between power loss ... Keywords: brushless DC motors; permanent magnet synchronous motors; optimal control; convex optimizati
This paper presents an educational tool developed for neural network (NN) control of brushless. DC (BLDC) motors. Neural networks courses are widely offered at the graduate and under- graduate level due to the successful applications of neural networ
Mar 19, 2002 - Multi-domain dynamic simulation is becoming an is- sue in the design of high performance mechatronic systems, where advances are foreseen only if the mu- tual interaction of different parts of the system is well understood. The modelli
Physics 101. â Some things we all knew at one time but forgot. â¢ Motors 101. â Pre-reqs Circuits 101 and Physics 101. â Motors 101 Lab .... DC gearhead motors ...
machine took the form of a 6-pole brushless permanent- magnet servo motor. The machine operated under ac control. The machine was tested using the fitted ... Axial section. Fig. 5. SPEED link in Motor-CAD. D. Experimental Validation. Fig. 6 shows the
In the following, a complete model-based control scheme is presented which avoids the latter disadvantages. Fig. 2 shows the overall scheme of the developed ...
copper losses, power interrupter losses, stator iron losses in the tooth and in the yoke, ... losses in three-phase outside brushless D.C. motors is reported.
module. The sample time used to realize the real implementation of the the position control is 100Âµs, and the processor used for the real tests is a floating point PowerPC at 1MHz, located in the real time DS1103 hardware of dSpace. This target inco
Engineering and Computer Sciences (E C S No. 2) www.sustech.edu. Optimal Speed .... adaptive or self-tuning of conventional PID controller gains. Tuning PID ...
prevent and control these diseases, which hinder economic progress and affect the well-being of populations ...... require a long course of pentavalent antimony - meglumine antimoniate or sodium stibogluconate. The ..... Depending on the local mosqui
The above 4 equations (Eq. 2.6 - 2.9) constitute a dynamic model of the induction motor on a stationary (stator) reference frame in space ... Ïa Ls. Lm p Ïa Lm. Iqsa . Vdsa =. -Ïa Ls. Rs + Ls p. -Ïa Lm. Lm p. Idsa . (3.2). 0.. Lm p. ( Ïa - Ï
analysis of converter's dynamic behaviour for design and implementation of converter control ... a) active and passive switch in DC/DC converter (BJT and diode).
Jun 18, 2014 - Abstract: Capacitive De-Ionization (CDI) is becoming a suitable alternative for desalination. The low ... depolarization energy stored in the first module, thus continuing with the water desalination. This ... has developed nanoporous
Jan 21, 2011 - in Patna and Nalanda, where IRS was occasional and on focal basis ..... Das ML, Roy L, Rijal S, Paudel IS, Picado A, Kroeger A,. 25. et al.
Jan 25, 2010 - massive spraying and mechanical control (like the destruction of breeding sites) can be efficient, to stop or contain the ... sprayers can be used to disperse the adulticide. This is done at night (be- ... rain gutters, old tires, buck
Optimum Vector Control for Brushless Motors Hardware and Software Design for Highest Performance and Lowest Whole-Life Cost
Field Oriented Control, or Vector Control, is preferred in systems using brushless motors; a number of microcontroller vendors offer FOC software as an aid to motor-control development. A new gen-
rotor, several commutation techniques are applicable to adjust the current in each phase to produce a net stator field in quadrature with
eration of MCUs that incorporate hardware-based FOC processing
now simplifies design challenges as well as achieving higher per-
> Brushless Motor Control Brushless DC motors offer several advantages over traditional brushed AC and DC motors, including lower materials costs, greater reliability, and longer lifetime. However, since brushless motors do not self commutate, torque control, which is fundamental to successful operation of any servo system, presents a more complex challenge. Several strategies have evolved for controlling torque in brushless motors, which perform commutation on the motor’s behalf as well as calculating the optimal current for each stator to produce the maximum torque.
Torque control for a brushless motor seeks to maximise torque by adjusting the current in the stator windings to produce a net magnetic field that is orthogonal – or in quadrature - to the rotor field. Any component of the stator field acting parallel to the rotor’s field will produce a force that has no turning effect. This direct component wastes energy and places additional stress on the rotor bearings. While maximising the quadrature component, torque control aims to minimise or, ideally, eliminate the direct component to ensure optimal efficiency and reliability. For controlling three-phase brushless motors, having three stator phases positioned at 120-degree intervals around the axis of the
Figure2: ARM® CortexTM-M3 microcontroller with integrated hardware based vector engine and analog circuit.
formance at lower operating frequencies.
Brushless DC motor
Figure1: Typical prinzip of a 3-phase BLDC motor; each phase is positioned on a 120° interval arround the axis.
the rotor field. Common to each method of commutation, the motor current is sensed and compared with the desired torque, and a proportional-integral (PI) function then acts on the resulting error signal to generate a correction. This correction signal is subsequently pulsewidth modulated and used to control the output bridge of the motor driver. In trapezoidal motor control, also known as 6-phase motor control, the stator currents have equal magnitude in the two phase pairs either side of the rotor, while the third stator is disconnected from the power source. Rotor-position data from three Hall sensors located in between each pair of stator phases determines which phase is to be disconnected. As the rotor turns the current in each phase is switched between the maximum positive value, zero, and the maximum negative value. The resulting trapezoidal current approximates to a sinusoidal waveform. Although the average stator field in any period is in quadrature
TMPM370FYFG with respect to the rotor field, the instantaneous net stator field can lead or lag by up to 30 degrees. At low rotor speeds this results in imprecise control, as well as high levels of audible noise.
> Sinewave Control Sinusoidal control produces smoother torque by applying sinusoidal current waveforms to the stator windings. The currents are mutually phase shifted by 120 degrees, so that the vector sum of the stator field is orthogonal to the rotor field. Compared to trapezoidal control, more accurate rotorposition information is required to generate the sinusoidal current waveforms. This may be achieved Voltage
Figure3: PWM motor supply voltage and sinusoidal winding current.
using an angular encoder or, alternatively, using sensorless position detection based on analysis of instantaneous motor current. However, accurate torque control is dependent on rapid computation of the required current value as soon as the rotor position is sensed. At high rotor speeds the limited bandwidth of the PI function results in an increasing lag between the calculated stator current and the actual rotor position, leading to ineffi-
Field Oriented Control (FOC): Mathematical technique utilized for achieving a separate control (decouple) of the field producing and the torque producing portions of the currents in a three-phase machine. In this scheme Stator current IS is decomposed into: Q-axis > Magnetizing current Id, producing a magnetic field > Quadrature current Iq, which controls torque.
) or at t (I s t S en rr Cu
Torque (Iq) Flux (Id)
> Field Oriented Control Field Oriented Control (FOC), also known as Vector Control, overcomes the poor low-speed accuracy of trapezoidal control as well as the high-speed inefficiency of sinusoidal control. By manipulating the motor currents and voltages with reference to the rotor’s direct and quadrature axes, FOC maintains a constant stator field in quadrature with the rotor field irrespective of any bandwidth limitations of the PI controllers. In FOC, the sensed stator currents are translated into rotor direct (D) and quadrature (Q) components by a transform function. To achieve maximum torque, the D and Q currents are then compared respectively with zero and the torque requested by the application. The resulting error signals are input to the two PI blocks, which
generate signals in the D-Q reference plane. These must then be transformed into the stator domain to generate the PWM signal for each stator phase. Figure 4 illustrates the functional blocks of a generic FOC function. Because the inputs to the PI functions are constant, FOC maintains high efficiency at all rotor speeds regardless of any limitations on PIcontroller bandwidth. However, to perform FOC in real time requires fast execution of the functions that first transform the sensed stator current signals into the rotor domain and subsequently transform the static PI values into the voltage-control signals for the output bridge. Software-based FOC places maximum demands on CPU performance and operating frequency, to complete the loop within an acceptable time period in relation to rotor speed. Other factors such as integration challenges and any licensing issues must also be borne in mind when developing a motor controller using softwarebased FOC.
> Hardware-Based FOC Performing time-critical FOC computations in hardware can increase the speed of the control loop, as well as reducing operating frequency and freeing valuable processor cycles to be used for application-level functions. Figure 5 illustrates a re-partitioned FOC function taking advantage of the hardware-based vector-control engine embedded in the Toshiba Figure4: Functional block of a generic FOC with sensorless back EMF detection.
TMPM370 and TMPM372 MCU for brushless-motor control. In this scheme, all FOC processing tasks that are fixed and independent of the application are performed in hardware. To perform these functions the MCU’s embedded vector engine implements functions including decoding, a scheduler for event and priority control, and calculation resources including a multiply-accumulate (MAC) block for computationally intensive operations. Two vector-control units implement the PI controllers and associated functions. By offloading the complex and time-critical processing to the vector engine, the TMPM370 restricts the software component of FOC to application-dependent tasks such as ω calculation and speed control. These are performed in the device’s 32-bit ARM Cortex™-M3 core. With these processing resources, the TMPM370 is able to complete the control loop within each PWM period, resulting in better control stability for PWM frequencies up to 100kHz. Even when operating at 40MHz (max. 80MHz), this MCU is not only capable of controlling two brushless Motor 1
Oscillation Frequency Detector (OFD): TMPM370 group is equipped with an Oscillation Frequency Detector (OFD) which supports IEC60730 class B regulation for Conformity Testing to Standards for Safety of Electrical Equipment. The oscillation frequency detector function is a hardware to Detection reset monitor CPU clock. This 32kHz L-freq OFDOUTn function automatically deOSC OFD tects abnormal clock opCPU eration without a complex 80MHz H-freq software and secures save OSC operation. budget and EMI. By complying with the one-MCU-for-one-motor convention, designers can use the TMPM372 operating at 40MHz to take advantage of cost and size savings without affecting performance. Both M372 and M370 are suitable for high-end motor control applications including next generation of appliances, pumps, industrial machinery, compressors, and HVAC (heating ventilation airconditioning) systems. Permanent magnet brushless AC/DC, stepper and 3-phase AC induction motors are all suitable for both devices.
Vdd TMPM370 About x 1.5 ~10
ADC Unit A
SW Shunt Resistance x3
Change monitor level low or high range
Shunt Resistance x1
ADC Unit B
Figure 5: 3-shunt and 1-shunt method supported, integrated op-amps and two seperated ADC units.
motors simultaneously, but also has been shown to outperform software-based vector control using a conventional MCU operated at 80MHz, thereby reducing challenges associated with thermal management, system power
Additionally, the TMPM370 and M372 both feature an oscillation frequency detector (OFD), which enables them to meet the IEC60730 class B safety standard. As well as the vector engine, inte-6-
> Conclusion FOC/VC overcomes the low-speed imprecision of trapezoidal motor control, as well as the high-speed inefficiency experienced with conventional sinusoidal control. in addition to reducing energy consumption, FOC delivers advantages such as lower audible noise, reduced wear, constant torque over the complete speed range including zero-speed operation, and good velocity control under varying load conditions.
grated analogue IP fulfils specific requirements for FOC such as 2x 11-channel 12-bit ADCs for fast current sensing and shutdown capability. An ADC-timing network including op-amp and comparator functions is also integrated, which enables precise measurement over the full positive and negative current range of the motor without requiring an external op-amp to perform level shifting.
Hardware-based execution of the computationally intensive FOC calculations, as well as built-in analogue IP optimised for motor control, avoids the complications and performance limitations experienced when implementing FOC in software.
TMPM370FYFG Starter and Evaluation Kit The BMSKTOPASM370(HI) is a ready-to-use starter and evaluation kit for motor control solutions requiring field oriented control algorithm. The kit provides an evaluation board, a 18V 3-phase BLDC test-motor, power supply and cables and a comprehensive package of software tools, application samples and documentation.
Key Features: • Cortex™-M3 core based 32-bit Microcontroller • Programmable Motor Drive by hardware • Vector Engine for sensored and sensorless field oriented motor control • Three shunt and one shunt resistor method supported • Supporting 3-phase BLDC and AC induction motors • Low speed vector control • High torque at zero speed Kit content:
BMSKTOPASM370(HI) BLDC motor control evaluation kit
• TMPM370 Evaluation board • 18V 3-phase BLDC Motor as test system • J-Link ARM Lite emulator via USB • 24V Power Supply (100 to 230V input) • 18V low voltage motor control provided on board • Designed for high voltage motor control with available material list • Safety control functions • Full isolation to communication circuit • Small LCD for stand-alone evaluation • GUI control via PC • Software package incl. BSP • Circuit diagram and pcb layout files • Application notes, documentation and source codes
Graphical user interface
Application examples: > Air conditioner
> Water pumps
> Home appliances
> Kitchen hood
> Heating pumps
> Fuel pumps
> Industrial motors
In addition to above selection, you can find out more about TOSHIBAs motor control solutions at: http://www.toshiba−components.com/motorcontrol -7-
Motor Control Solutions TMPM370FYFG Cortex-M3 based Vector Control MCU
Field-Orientated (Vector) Motor Control Sensored and Sensorless Sine Wave Programmable Motor Drive For 3-phase BLDC and AC induction motors Hardware based motor control
Your vector control solution High Performance Motor Control The TMPM370FYFG is a high-performance ARM Cortex™-M3 based 32-bit microcontrollers that offers accurate, hardware-based vector control of high-end, three-phase motor applications. Ideal for motion control in home appliances and industrial applications it reduces the need for additional components while providing significant benefits over software-based vector control running on a microcontroller. It is a compact, highly efficient device that can simplify applications requiring precision control of sensored and sensorless three-phase brushless DC (BLDC) motors or three-phase AC induction motors.
TMPM370FYFG CPU core (ARM Cortex-M3) > Max. operating freq.: 80MHz (PLL x8) > Operating voltage: Peripheral I/O = 4.5V ~5.5V > Debug circuit: JTAG or SWD > Power Saving operation > Clock gear (for dividing clock to 1/2, 1/4, 1/8 or 1/16) > Standby mode (IDLE/STOP) Built-in functions > PMD3+ (Programmable Motor Control) > Timer for motor control: 2 channel > Vector engine: 1 unit > Encoder input: 2 channel > OP-Amplifier: 4 units > Comparator for emergency stop: 2 units > 12-bit A/D converter: 2unit (22ch) > 16-bit timer counter: 8 channel > Serial interface: UART/SIO: 4channel > Power On Reset (POR) > Voltage Detection (VLTD) > Oscillation Frequency detector (OFD) > External Interrupt: 16ch
PMD / ROM RAM VE (kB) (kB)
TMPM373FWDUG* 1 / 1
*) Under planning / development
TMPM370FYFG Key Features FEATURE
Programmable Motor Drive
Hardware based motor control like a co-processor requires less software development and system power. A flexible register control provides automatic settings or a customized control of 3-phase BLDC or induction AC motors. The PMD unit provides a 3phase complementary PWM signal. Up to 150.000 rpm can be supported.
Dual or Single Motor Control
The combination of the 80 MHz CPU with hardware vector calculations and autonomous PWM channels give the M370 MCU the throughput needed to control two motors at the same time.
Vector Engine (FOC)
Field-oriented control of AC motors require extensive mathematical calculations to translate between Id/Iq space and the physical state of the motor. The M370 MCU manages this translation in hardware, freeing up the CPU to run the motor models.
Integrated programmable gain operation amplifier for back EMF detection, comparator for emergency stop and an incremental encoder for rotation direction and position detection, noise filter and three phase sensor input.
Dual 12bit ADC unit
Two A/D converter units with 11 channels each with internal trigger, single/ repeat and monitoring function. Fast conversion speed of 2µsec (@40MHz)
Single and three shunt resistor method
For sensorless motor control the motor current has to be measured. TMPM370 is supporting the one shunt and three shunt resistor method.
Oscillation Frequency Detector
Hardware clock monitoring in order to support IEC/EN 60730 classB security standard.
Toshiba‘s proprietary embedded NANO FLASHTM. Quick write/erase and response time; no wait states up to 100MHz.
5V operation voltage
5V single operation voltage supporting industrial and home appliance requirements.
Serial Wire JTAG interface
Debugging interface with an In-Circuit-Emulator (ICE) and the Embedded Trace MacrocellTM (ETM) unit for instruction trace functionality.