application note: space vector modulation of a 3-phase ac ...space vector modulation of a 3-phase ac...

AN038201-0816MultiMotor

SeriesMultiMotor

Series

Abstract

Space Vector Modulation (SVM) techniques can be applied to AC induction motors (ACIM), permanent magnet synchronous motors, and BLDC motors. A 3-phase ACIM is controlled by creating a rotating voltage reference vector within a hexagon. The speed of rotation of this voltage reference vector determines the frequency of motor rotation. The Space Vector Modulation application discussed in this application note uses the Voltage per Hertz (V/F) control principle with or without a Hall sensor functioning as a tachometer for speed feedback to control an ACIM motor.

Continual cost pressures and increased consumer expectations have driven design engi-neers to seek minimal hardware solutions that extract maximum performance from motors used in consumer goods. This application note demonstrates how Zilog’s Z16FMC MCU can implement an efficient and cost-conscious V/F vector modulation of an AC induction motor.

The source code file associated with this application note, AN0382-SC01, is available free for download from the Zilog website. This source code was tested with version 5.18 of Keil MDK for Zilog’s Z32F138 ARM Cortex MCUs. Subsequent releases of this software may require you to modify the code supplied with this application.

Z32F128 Series Flash Microcontrollers

The Z32F128 Series of Flash MCUs is based on Zilog’s advanced 32-bit ZNEO32! CPU core allowing simultaneous operation of two inverter bridges. The MCUs in this series are optimized for motor control applications and support control of single- and multi-phase variable-speed motors. Target applications include consumer appliances, HVAC systems, factory automation, refrigeration, and automotive applications.

Figure 1 shows a block diagram of the Z32F128 MCU.

Note:

AN038201-0816

Application Note

Space Vector Modulation of a 3-Phase AC Induction Motor with the Z32F128 Microcontroller

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http://www.zilog.com/docs/appnotes/an0382-sc01.zip

Space Vector Modulation of a 3-Phase AC Induction Motor with the Z32F128 MCUMultiMotor Series Application Note

To rotate a 3-phase motor, three AC voltage signals must be supplied and phase-shifted 120° from each other. To control a 3-phase motor, the MCU must provide six Pulse Width Modulation (PWM) outputs. The Z32F128 MCU features a flexible PWM module with three complementary pairs – or six independent PWM outputs – supporting deadband insertion and fault protection trip input. These features provide multiphase control capa-bility for multiple motor types and ensure that the motor operates safely by effecting an immediate shutdown of the PWM during a fault condition.

Discussion

An electric motor consists of a stator and a stationary frame in which a rotating compo-nent, or rotor, is mounted on a shaft and bearings. In a 3-phase ACIM motor, the stator is laced with three sets of inductor windings energized by three AC voltage inputs that are phase-offset 120° from each other to produce a rotating field of magnetic flux. This stator

Figure 1. Z32F128 MCU Block Diagram

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flux field induces a voltage onto the rotor which also generates a rotor flux field which then interacts with the stator flux field, resulting in torque on the output shaft.

In a 3-phase motor control application, the input to the motor is produced by a 3-phase inverter bridge consisting of six switching devices. This inverter bridge forms three legs, each operating in complementary PWM. Each leg or MOSFET pair connects to either the ground voltage or the bus voltage depending on the ON/OFF state of the MOSFETS, which are controlled by the PWM signals from the Z32F128 microcontroller. The micro-controller applies sinusoidal changing PWM signals to this inverter bridge to generate three approximately-sinusoidal AC waveforms on the bridge outputs to which the ACIM motor is connected, with the required 120° phase offset.

The duty cycle of each microcontroller’s PWM output is varied, to control the period and amplitude of the generated AC signal, which in turn determines the speed and torque of the motor.

Theory of Operation

When a constant ratio of applied frequency and voltage is maintained, a constant flux throughout a wide operating range is created in the air gap between the rotor and the sta-tor. This control method is referred to as Voltage per Frequency, or V/F control.

In this application, using the V/F method, space vector modulation is the means by which a rotating magnetic field is created in the stator, and via induction, ultimately in the rotor. Space vector modulation techniques utilize an additional fifteen percent of the available bus voltage, thereby increasing the efficiency of the motor. The space vector modulation scheme applied here is referred to as alternate-reverse switching. This technique mini-mizes inverter switching and therefore, linear switching power losses. Intrinsic to ACIM motors is the slip frequency, which is the difference between the synchronous speed of the stator and rotor flux fields. This slip frequency must be controlled with a V/F profiler as discussed later in this document.

Using ordinary sinusoidal PWM techniques, the neutral point of the phase voltages are confined to Vbus/2, as shown in Figure 2.

The advantage of space vector modulation is that the neutral point of the phase voltages is not constrained to one-half of the bus voltage, as illustrated in Figure 3.

Figure 2. Neutral Point Confinement of Sinusoidal PWM Phase Voltages

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Additionally, unlike sinusoidal PWM, which generates sinusoidal currents separately in each push/pull stage of the inverter, the Volt per Hertz (V/F) space vector modulation technique operates the entire inverter as a single unit to produce sinusoidal currents. In doing so, the inverter is operated in eight different states within the hexagon. Two of these states are referred to as zero vectors because they produce no voltages. The remaining six states produce non-zero voltages. The rotating reference voltage VS within this hexagon, shown in Figure 4, is represented by a space vector VS in Equation 1, which follows.

Equation 1

Figure 3. Space Vector Modulated Phase Voltages not Confined to a Neutral Point

Figure 4. The Rotating Reference Vector VREF Within The Hexagon

V4 (011) 180 degree

V3 (010) 120 degree

V2 (110) 60 degree

V5 (001) 240 degree

V6 (101) 300 degree

V1 (100) 0 degree V0 (000)

V7 (111)

r1

r2

Θ

Vs

VSVmagVbus---------------- e×

jθ=

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The ejθ part of Equation 1 can be represented by Euler’s identity in Equation 2, which states that the VS vector is comprised of a real component and an imaginary component.

Equation 2

This VS vector is formed, as shown in Equation 3, in which sinusoidal voltage changes present at each motor phase winding produce sinusoidal currents in each phase to generate magnetic flux fields, as shown in Equation 4.

Equation 3

Equation 4

In Equation 4, NS is the number of inductor turns, μ0 is the permeability of space, and Lg is the air gap.

The reference vector VS must be converted to the appropriate switching signals and applied to the inverter bridge using Equation 5.

Equation 5

As indicated in Equation 5, to generate this rotating vector VS, the angular position within any two base vectors, the base vectors themselves, and the scalar coefficients r1 and r2 must be known, as shown in Figure 4.

After obtaining the angle theta of rotation and the adjacent base vectors within the hexa-gon, the scalar coefficients for the adjacent base vector r1 and r2 must be calculated to time-modulate the base vectors V1 and V2 to generate the rotating voltage reference vector VS within the hexagon. This space vector can be located anywhere between any of the base vectors V1 to V6. This commutation scheme is different from the six-step commutation scheme which has six distinct commutation steps per electrical revolution.

Figure 5 shows the location of the reference vector VS, which is located between base vec-tors V1 and V2.

ejθ θ( ) j θ( )sin+cos=

VS t( ) Va t( )× ej0× Vb t( )× e× j120

Vc t( ) ej240×+ +=

BS t( )NS μ0×2 Lg×

--------------------- ia t( ) ej0× ib t( ) e

j120× ic t( ) ej240×+ +

=

VS r1 v1×( ) r2 v2×( )+=

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After the angular information is obtained, the scalar quantities r1 and r2 are calculated by equations 6 and 7.

Equation 6

Equation 7

In the above equations, m is the magnitude of the rotating space vector VS within the hexa-gon and θ is the angle of the reference vector VS with respect to the base vectors V1 and V2.

The time duration for which the adjacent base vectors are modulated to obtain the refer-ence vector is calculated by using equations 1, 2, and 3 to compute equations 8 through 10.

Equation 8

Equation 9

Figure 5. The Location of Reference Vector VS Between Base Vectors V1 and V2

r2V2

60 degree

Θ

Vs

r1V1 V1

V2

r2 m 3 Δθ( )sin×=

r1 m 3 60 Δθ–( )sin×=

T0 1 r1– r2–( ) T×=

T1 r1 T×=

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Equation 10

In these equations, T is the sum of T0, T1, and T2 and cannot be greater than the time period of the PWM. Next, T0 becomes the time period for which either or both zero vec-tors are applied in combination with T1 and T2, as shown in Figure 6.

To find the time values T0, T1, and T2, the angles are determined by using V1 as the refer-ence axis going counterclockwise to find the base vector angle to be subtracted from the angle of the reference vector.

For example, using Equation 1, if the bus voltage is 24 V and the desired reference vector magnitude is 12 V, then the reference vector VS is calculated using Equation 11.

Equation 11

In Equation 11, the angle is 190° and the adjacent base vector is V4, which is 180°. There-fore, r1 and r2 are calculated by using equations 6, 7, and 8 to compute equations 12 and 13.

Equation 12

Equation 13

If the PWM period is T = 50 μs, then the time duration for either zero vector V0, V7 is shown in equations 14 through 16.

Figure 6. The Switching Times for Base Vectors V1, V2, and Zero Vectors

T2 r2 T×=

VS

VmagVbus--------------- e

j190×=

r1 31224------× 60 190 180–( ) ]–[sin× 0.663= =

r2 31224------× 190 180–( )sin× 0.15= =

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Equation 14

The time duration for T1 is calculated using Equation 15.

Equation 15

The time duration for T2 is obtained from Equation 16.

Equation 16

Space vector modulation has an advantage over ordinary sinusoidal modulation because it allows for different switching combinations. For example, using T1 and T2 based on the choice of the null vectors which are applied for duration of time T0 and applying the zero vectors V0, V7, or both, results in different switching patterns to generate either less total harmonic distortion or to reduce linear switching power losses in the switching devices. V0, V7 zero vectors may be used to obtain the regenerative braking effect, especially when using ACIM.

For example, to reduce linear switching losses, either of the V0 or V7 zero vectors can be applied in sequence. V0 is applied as the zero vector in the sequence T1–T2–T0; the V7 zero vector is used in the same sequence. In either case, each of the three phases in the inverter does not switch for one third of the duration of a cycle.

Different combinations of switching sequences can be applied, but may have different, and perhaps undesirable effects on the inverter circuit, depending on the size of the boot-strap capacitors used for the high- and low-side drivers. However, space vector modula-tion allows for a variety of switching schemes to obtain the desirable effect and meet customer-specific requirements. This application note uses the alternate reverse switching mode, in which each column corresponds to vectors one through six, as shown in Figure 7.

In the reverse switching mode, only one inverter leg at a time switches to reduce linear power-switching losses. The null vectors are alternated upon each space vector modula-tion sequence in reversed order after each zero vector, as shown in Figure 8.

Figure 7. Example of PWM Timings Using an Alternate-Reverse Switching Mode

T0 1 r1– r2+( ) T 9.3μs=×=

T2 r1 T× 33.2μs= =

T2 r2 T 7.5μs=×=

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Application

To apply the space vector theory, the Z32F128 microcontroller’s PWM module is config-ured to operate in three complementary output pairs. Each output pair controls one com-plementary source/drain transistor pair in the inverter bridge. The PWM module is configured to insert a deadband between ON states to prevent leakage that might occur if one transistor in a pair turns on before the other is fully off. Each PWM output pair pro-duces a stream of complementary on/off pulses to activate the corresponding source or drain transistor in the inverter bridge. The voltage of each bridge output varies with the source/drain pulse duty cycle. The input to the space vector modulation software function is the angle and the magnitude.

The period of each PWM cycle is configured to be 50 μs and generates an interrupt request at the end of each cycle to process the speed integration to form the angle, the vector decomposition based on the angle, and the space vector modulation voltages based on the magnitude. This data is then loaded into the three PWM registers for Phase A, Phase B, and Phase C.

The simplest way to control an ACIM is via the V/F method without any sensing feedback of the rotor. The speed demand comes from a potentiometer to calculate the frequency demand with a constant proportional frequency to voltage ratio. However, if the Hall sens-ing feedback option is desired, then a single Hall sensor is used as a tachometer to deter-mine the speed of the motor. Additionally, the motor can be operated in either open loop or PI closed loop control. With the PI closed loop method, the Timer 0 ticks are captured at every rising edge of the Hall and compared to the requested speed received through a UART terminal or potentiometer, when in Standalone Mode. The frequency of the rotat-ing vector is calculated as shown in Equation 17.

Equation 17

In the above equation, the Look-Up Table (LUT) offset value is a 16-bit integer index of which only the upper byte is used to select the LUT entries. The synchronous speed of the rotor is calculated as shown in Equation 18.

Equation 18

The Timer 0 ticks captured for the PI loop are calculated as shown in Equation 19.

Figure 8. space Vector Modulation Sequence

Frequency Look-Up Table offsetPWM period Look-UpTable size×-------------------------------------------------------------------------------------------=

RPM 120Frequency

Poles-------------------------------×=

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Equation 19

To change the frequency of the motor, the upper byte of a 16-bit interpolating sine table index is used to fetch the next PWM sine value from the LUT. Assuming the sine fre-quency is 60 Hz, the offset value for the sine table pointer is calculated as shown in Equa-tion 20.

Equation 20

In the above equation, 20000 is the PWM frequency.

The (rounded) offset value represents the frequency demand, which is integrated to form the (theta) angle of the rotor. The upper byte of the theta value then becomes the index to the 256 sine value table.

Depending on the frequency demand, the values of the upper byte of the sine index can change with higher granularity, hitting each sine array value more or fewer times while the sine index continuously rolls over. Using this method, the lowest period using a16-bit pointer to a 256-element sine table is represented by Equation 21.

Equation 21

Because of the interpolating index method, the increment values in the upper byte of the sine table index will be small, changing only in fractions to achieve higher frequencies.

Speed Calculations

The angular time periods of the rotor are represented by elapsed timer ticks and are cap-tured upon each rising edge of the Hall interrupt as described in the previous section. These timer ticks are then compared with the demand speed coming from a potentiometer in Standalone Mode, or from the UART when in Terminal Mode. The captured timer ticks period represents the actual speed of the motor and is compared with the demand value for closed-loop operation.

The angular speed is represented by Equation 22.

Equation 22

TimerTicks

MCU clockTimer0 prescaler------------------------------------------------

LUToffsetPWM period LUTsize×--------------------------------------------------------------------------------------------------------------------------------=

SineIndexOffset 60 65536×20000

----------------------------- 196= =

65535 50μs 3.277 ondssec=×

ω ddt----- θ×=

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In the above equation, θ is

The RPM of the motor in this application is calculated using Equation 23.

Equation 23

In the above equation, N is the number of poles and F is the frequency. By substitution, use Equation 24 to obtain the RPM.

Equation 24

Voltage per Hertz ControlAs shown in Figure 9, the base frequency is at the maximum flux field with the speed at full armature current and voltage.

The software algorithm ensures that the ratio of voltage and frequency remains constant over the full speed range to maintain a constant flux field in the air gap of the motor. A boost voltage, or minimum voltage and frequency limit, is implemented to avoid high cur-rents through the motor windings at very low speeds in which the complex reactance of the motor windings is very low. In this application note, the total reactance of the motor is represented by Equation 25.

Figure 9. Voltage Per Hertz Control

2 π f××

RPM 120 F×N

-------------------=

RPM120

tableIndexValuePWMperiod SineTableSize×-----------------------------------------------------------------------------------×

N----------------------------------------------------------------------------------------------------=

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Equation 25

In the above equation, R is the real resistance and XL and XC are the inductor reactance and capacitive reactance, respectively.

V/F Profiler and Slip FrequencySlip frequency is intrinsic to AC induction motors. In an AC induction motor, the stator flux field is rotating at synchronous speed according to the sinusoidal frequencies of the currents that produce this stator flux field. The resulting induced flux field in the rotor interacts with the stator flux field and causes a torque to rotate the motor at the synchro-nous speed minus a frequency that is referred to as slip frequency. In effect, the rotor fre-quency is always less than the stator field frequency, which is necessary because only an alternating current field can induce a voltage in the rotor. If the rotor frequency and stator frequency were the same (from the perspective of either stator or rotor), there is no alter-nating field and therefore no voltage is induced to cause a torque from the interacting rotor and stator force field. This electromagnetic behavior is depicted in Equation 26.

Equation 26

In the above equation, the subscript S refers to the stator. This equation states that the rate of change of current through an inductor induces a voltage. This alternating stator voltage induces a voltage onto the rotor to cause an alternating current in the rotor, with a resulting rotating flux field in the rotor.

The interaction of rotor and stator flux fields must be controlled with a V/F profiler. If the Hall sensor option with closed loop feedback is enabled in the firmware, it is possible that the closed loop will adjust the stator frequency faster than the rotor frequency can respond, so that the stator frequency will run off, causing the slip frequency to become too large and subsequently stall the motor. Additionally, if the rate of deceleration is too high, the slip frequency becomes too large while the potentially damaging excessive Back-Electro-motive Force (BEMF) voltage is fed back to the supply, unless the generated BEMF volt-age is desired during deceleration for regenerative braking or battery-charging purposes. To control the slip frequency and its associated effects, a V/F profiler is implemented to control the rate of frequency changes.

If the option to operate the ACIM with Hall sensing feedback and no closed loop speed control is enabled, the slip frequency is dynamically calculated and optimized, based on the rotor frequency information which is provided by the Hall sensor.

The ACIM motor used for this application is a BOSCH 250 V, 2 A motor (500 W) shown in Figure 11 on page 15. However, for development purposes with Zilog’s MultiMotor Con-trol Development Kit, this software was designed to operate the motor at 30 V. Therefore,

Z R2

XL XC–( )2+=

VS LSddt-----× IS×=

Note:

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the V/F profiler may require adjusting for acceleration and deceleration rates when operat-ing a customer ACIM at higher voltages.

Equipment Used

The following equipment is used for the setup to demonstrate the space vector modulation technique. The first four items are included in the MultiMotor Development Kit (ZMULTIMC100ZCOG).

• MultiMotor Development Board (99C1358-0001G)

• 24V AC/DC power supply

• LINIX 3-phase 24VDC, 30W, 3200RPM BLDC motor (45ZWN24-30)

• Opto-Isolated UART-to-USB adapter (99C1359-001G)

• Z32F128 MultiMotor MCU Module (99C1461-001G) – Order separately

• Keil ULINK2 debugger – Order separately

• Digital oscilloscope

• PC with Internet access and at least two open USB ports

Hardware Setup

Figure 10 shows the application hardware connections required to operate the motor with the space vector modulation method.

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Figure 11 displays the BOSCH AC induction motor used for the development of the code for this application note.

Figure 10. MultiMotor Demo Kit and Linix BLDC Motor

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Testing Procedure

Observe the following procedure to test space vector modulation on the Z32F128 MCU Module.

1. Download and install Keil MDK–ARM µVision IDE version 5.20 (or newer) on your PC from the Keil website.

2. Download the AN0382-SC01.zip source code file from the Zilog website and unzip it to an appropriate location on your PC.

3. Connect the hardware as shown in Figure 10.

a. The cables from the Keil ULINK2 debugger and the UART-to-USB adapter must be connected to two of the PC’s USB ports.

b. Download and install the drivers for the Keil ULINK2 and the UART-to-USB adapter, if required.

4. Power up the MultiMotor Series Development Board using the 24 V DC adapter that is included in the Kit.

Figure 11. BOSCH AC Induction Motor

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The order of the phase wire connectivity affects the spin direction of the motor but is oth-erwise irrelevant. The 24 V power supply that is included in the kit may not suffice.

5. Using a serial terminal emulation program such as HyperTerminal, TeraTerm, or Real-Term, configure the serial port to 57600-8-N-1-N. A console screen should appear on the PC which will show the status of the motor and allow changes to the motor’s oper-ation.

6. Launch Keil µVision version 5.20 (or newer), select Open Project from the Project menu, browse to the directory on your PC to which the AN0382-SC01 source code was downloaded, locate the AN0382_SC01.zdsproj file, highlight it, and select Open.

7. Ensure that the RUN/STOP switch on the Z32F128 MCU Module is in the STOP position.

8. In Keil µVision, compile and flash the firmware to the Z32F128 MCU Module by selecting Rebuild All target files from the Project menu. Next, select Debug →

Start/Stop Debug Session, followed by Debug → Run.

Figure 12. Motor Phase Wire Connections

J1J5J4

Note:

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9. Set the RUN/STOP switch on the Z32F128 MCU Module to RUN. The motor should begin turning.

10. In the GUI terminal console, enter the letter U to switch to UART control; a menu similar to the example shown in Figure 7 should appear. As a result, commands can now be entered using the console to change the motor’s operation.

11. On the open terminal window, enter the letter U on your keyboard to enter UART Control Mode to control the motor by entering commands on the computer keyboard. Figure 14 shows the console display in UART Control Mode.

Figure 13. Console Display in Hardware Control Mode

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12. In the window that appears, enter the letter S to start the motor operation, and enter any of the available operation options.

13. A data logger is used to report vital motor control data, as shown in Figure 14. The data displayed includes:

– Operating temperature

– Speed

– Operating current

– Total run time

– Spin direction

14. Upon entering D, recorded data is displayed in a continuous fashion. To stop this data display from continuing, enter a Ctrl + C command, as shown in Figure 15.

Figure 14. Console Display in UART Control Mode

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You can now add your application software to the main program to experiment with addi-tional functions.

Results

Three oscilloscope probes were connected to the MultiMotor Series Development Kit to Phase A, Phase B, and Phase C to show three alternate reverse switching patterns. Scope probes were connected to the BEMF voltage dividers to monitor the generated BEMF voltages and to view the associated switching pattern waveforms.

Figures 16 through 18 show the alternate-reverse space vector modulation pattern on Phase A, Phase B, and Phase C at three different time instances.

Figure 15. Enter a Ctrl + C Command to Stop the Display of Recorded Data

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Figure 16. Alternate Switching Pattern at Time 1


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Figure 19 shows the three phase voltages and one of the three current wave forms (shown in green).

Alternate-reverse voltage wave forms have been measured with the oscilloscope at the BEMF voltage dividers consisting of R24, R29, C30 (BEMF_A), R25, R30, C31 (BEMF_B), and R26, R31, C32 (BEMF_C).

Code Execution Time of Relevant FunctionsThe time required for code execution of relevant functions is listed in this section. Execu-tion times are based on the external 80 MHz clock frequency.

PWM interrupt service code: ~2µs


Figure 19. Three Phase Voltages and One Current Wave Form (Green)

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Tachometer interrupt service: ~1.2µs

SVM decomposition function call (SVM timing calculations): ~0.5µs

Compiler Optimization SettingsEnsure that the following Compiler Optimization options are set:

• Optimization: Level 1 and optimized for time

Summary

The purpose of this application note is to demonstrate the operation of an ACIM-type machine using the Space Vector Modulation technique with the Voltage per Hertz (V/F) principle. To obtain a constant flux in the air gap, the ratio of voltage and frequency is held constant throughout the speed range of the motor. To generate sinusoidal voltages and cur-rents, a voltage reference vector is rotated 360° within a hexagon. Each of the six sectors within this hexagon creates unique switching patterns for space vector modulation. Space vector modulation has the advantage of utilizing about fifteen percent more of the avail-able bus voltage and the freedom to implement multiple forms of SVM switching patterns to meet design-specific requirements. The space vector modulation scheme discussed here uses an alternate-reverse switching pattern.

Formulas are shown to calculate the space vector modulation timings and resulting motor frequency. Because the frequency calculations include the PWM period, all space vector sinusoidal wave constructions are executed in the PWM interrupt service routine. The exe-cution time for the sine wave reconstruction in the PWM interrupt service routine is approximately 2 μs. The execution time of the tachometer interrupt service routine is approximately 1.5 μs. Both of these execution times are based on a 80 MHz internal clock. The tachometer interrupt service routine captures the Timer 0 ticks upon each rising edge interrupt of the Hall for open- and closed-loop speed calculations. The calculated speed value from the timer ticks is integrated in the PWM interrupt service routine to form the interpolating 16-bit theta angle variable, of which only the high byte is used to fetch the next value from the sine LUT.

In essence, all speed calculation values are offset to the interpolating 16-bit sine LUT index. Depending on the demand speed, these values will increase or decrease the fre-quency of rotation of the reference vector. Space vector modulation has the advantage of commutating the ACIM with less acoustical and electrical noise and, depending on the switching scheme, fewer linear power switching losses. The effects of total harmonic dis-tortions and linear switching power losses can be further manipulated by applying differ-ent space vector modulation switching schemes. This technique allows for higher life expectancy of ripple current capacitors and ball bearings because the sinusoidal commuta-tion approach causes virtually no torque or current ripple in an ACIM motor.

A simple V/F profiler and slip frequency is also discussed, and a V/F profiler is imple-mented to account for the rates of frequency increase and decrease to control the slip fre-quency.

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The example application and techniques described in this document should prove helpful for anyone who intends to develop motor control applications based on the Z16FMC series of microcontrollers.

References

To learn more about this topic and the ZNEO32! Series of motor control products, refer to the documents listed in Table 1.

Table 1. List of References

Topic Document

Z32F128 Evaluation Kit Z32F128 Evaluation Kit User Manual (UM0277)

Z32F128 MCU Z32F128 MCU Product Specification (PS0345)

Motor Control Vector Control and Dynamics of AC Drives (Monographs in Electrical and Electronic Engineering); D.W. Novotny and T.A. Lipo.

Short Course on Electric Drives: Understanding Basics to Advanced Control & Encoderless Operation: a recording of the Internet-based short course presented on May 12, 2005 by Professor Mohan and edited to fit on a DVD; Ned Mohan, University of Minnesota, 2005.

Lehrstuhl fuer Elektrische Antriebssysteme und Leistungselectronik; Ralph Kennel, Technische Universitaet Muenchen.

Electric Machinery; Peter F. Ryff.

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http://www.zilog.com/docs/devtools/UM0277.pdf

http://www.zilog.com/docs/PS0345.pdf

AN0382 of 29

on Motor with the Z32F128 MCUltiMotor Series Application Note

Appe

BOO se

.

ut

PWML0PWMH0

PWMH1BEMF_A

BEMF_BPWML1

PWMH2

HSBHSC

PWML2BEMF_C

HSA

PWML0U_LPWMH0U_H

V_H PWMH1BEMF_A

BEMF_BPWML1V_L

PWMH2W_HW_L PWML2

CS1+BEMF_C

CS1- CS_ACS2+ CS_BCS2- CS_C

TEMP

SCK

MOSI

VCC_3v3

MISO

SS-

VCC_3v3

C

0.

J4

HDR/PIN 1x16

12345678910111213141516

U2

S25FL032P

GND4

VCC8

CS1

WP3

SO2

HOLD7

SCK6

SI5

J2

DR/PIN 2x15

1357911131517192123252729 30

282624222018161412108642

J3

123

01-0816

Space Vector Modulation of a 3-Phase AC InductiMu

ndix A. Schematic Diagrams

Figures 20 and 21 show the schematic diagrams for the Z32F128 MCU Module.

Figure 20. Z32F128 MCU Module, #1 of 2

ONVBUS CTRL

MCU

T

SPEED CONTROL

Since this chip does not have an input for differential amplifier we have to ua single-ended current measurement So, on the main board R15 and R20 should be replaced with 0 Ohm resistorsNow CS- = GND, and CS+ is an input to AN3 - we can configure it with or withoAmplifier

PROTECTION

OVERVOLTAGE

RESET

NMI

R18 = Big Wheel or R28 = Small Wheel

ONLY ONE SET OF SHUNT 1&2, 4&5, 7&8 OR2&3, 5&6, 8&9SHOULD BE PRESENT

1 2 34 5 67 8 9

J13

XOUT

VBUS_M

ENABLE

HSBHSC

Vbus_MENABLE

HSA

ENABLEVbus_Ctrl

VCC_3v3

XIN

TxD0RxD0

nRESET

TCKTMS

TDO

PRTIN0OVIN0

PWMH0PWML0PWMH1PWML1

PWMH2PWML2

TDOnRESET

nTRSTTDITMSTCK

NMI

nRESET

NMI

TDI

nTR

ST

BEMF_ABEMF_BBEMF_C

MISOMOSISCK

SS-

CS1+

HSA

HSBHSC

Vbus_MTEMP

Vbus_Ctrl

OVIN0

PRTIN0

CREF1CREF0

CS_A

CS_CCS_B

PA2/AN2/CP2

PA1/AN1/CP1

PA0/AN0/CP0

VCC_3v3

VCC_5VM

VCC_3v3

VCC_3v3

VCC_3v3

VCC_3v3

VCC_3v3

VCC_3v3

RXD0TXD0

REDYELGRNDIRPC9

1

1uF

R1010K

SH4

shunt

Y1

8 MHZ

C6

0.1uF

C4680pF

C11

0.01uF

R3 10K

SH3

shunt

C13

1000pF/1nF

C9

0.01uF

J12

12

R285K 1

3

2

J5

123

C5

0.1uF

SW3B3U-1000P

1 2

R81K

R12 10K

R9 10K

R6 10K

SW1B3U-1000P

1 2

R210K

R16 10K

R5 10K

SW4B3U-1000P

1 2

SH2

shuntR17 0 ohm

R110K

C12

0.01uF

R7 10K

SW2B3U-1000P

1 2

C8

0.01uF

7

1

8

3

954 62

HDR/3x3

J13

1 2 34

5

67

8

9

H

R4 10K

C2680pF

C3680pF

R19 1KC10

0.01uF

J1

HDR/PIN 2x10

12345678910

11121314151617181920

R185K

13

2

R1110K

U1

AC33M6128L

GN

D1

PA

0/A

N0/

CP

02

PA

1/A

N1/

CP

13

PA

2/A

N2/

CP

24

PA

3/A

N3/

CP

35

PA

4/A

N4/

T0O

6

PA

5/A

N5/

T1O

7

PA

6/T2

O/A

N6/

CR

EF0

8

PA

7/T3

O/A

N7/

CR

EF3

9

AG

ND

10

AV

DD

11

PA

8/A

N8

12

PA

9/A

N9

13

PA

10/A

N10

14

PA

11/A

N11

15

PA

12/S

S0/

AN

1216

VDD17GND18PA13/SCK0/AN1319PA14/MOSI0/AN1420PA15/MISO0/AN1521PB0/MP0UH22PB1/MP0UL23PB2/MP0VH24PB3/MP0VL25TEST26SCANMD27PB4/MP0WH/T9C28PB5/MP0WL/T9O29PB6/PRTIN0/WDTO30PB7/OVIN0/STBYO31PB8/PRTIN1/RXD332

VD

D33

GN

D34

TXD

3/O

VIN

1/P

B9

35M

P1U

H/P

B10

36M

P1U

L/P

B11

37M

P1V

H/P

B12

38M

P1V

L/P

B13

39M

P1W

H/P

B14

40M

P1W

L/P

B15

41G

ND

42V

DD

43S

WC

LK/T

CK

/PC

044

SW

DIO

/TM

S/P

B1

45N

MI

46V

DD

47G

ND

48

SWO/TDO/PC249

TDI/PC350

nTRST/PHA0/T0C/PC451

PHB0/T1C/RXD1/PC552

PHZ0/T2C/TXD1/PC653

T3C/SCL0/PC754

SDA0/PC855

T8C/CLKO/PC956

nRESET/PC1057

T8C/BOOT/PC1158

TXD0/PC1559

RXD0/PC1460

XOUT/PC1361

XIN/PC1262

VDD63

GND64

AN0382 of 29


STOP/RUN

DIRECTION

EMOVE SHUNTHEN OBSERVINGCLKOUT

VCC_3v3

R24100K

SW6

EG1218

1

32

SW5

EG1218

1

32

J7

R25100K

01-0816


Figure 21. Z32F128 MCU Module, #2 of 2

3.3 OK

SCLKOUT

RWS

VCC_5VVCC_5V

VCC_3v3

VCC_3v3

VCC_5V

VCC_5V

VCC_5VM

VCC_5VL RED

YEL

GRN

DIR

RXD0TXD0

PC9

D3

YELL

21

J10

1x6 RT-ANGL

123456

R22

330

D1

PMEG3020

32

1

C17

0.1uF

C14

0.1uF

R27

100 ohm

U3

NCP551SN33T1G

Vin1

Enable3

GND2

NC4

Vout5

C15

4.7uF

R26

100 ohm

R21330

J11

12

J6

1 2 3

D61N4448W

R20

330

1 2 3

R23

330

J9HDR/PIN 1x3

1 2 3

SH1

shunt

J8

123

D2

RED

21

D4GREEN

21

C16

4.7uF

D5

GREEN

21

AN0382 of 29


FOR USE WITH AC MOTOR

Phase_C

HSCHSBHSA

Phase_APhase_BPhase_C

GC_L

GC_H

VCC_3v3

ENABLE

R6150K

R2310K

R13150K

C110.1uf

C5

0.1uF, 50V

N055T

C8

0.1uF, 50V

N055T

Q3

IXTY64N055T

1

23

4

Q6

IXTY64N055T

1

23

4

J5

2 POS

12

R2110K

J3

5-POS

12345

J1

3-POS

123

D4

BAS16V

4

1

3

5

6

2

01-0816


Figures 22 and 23 show the schematic diagrams for the MultiMotor Main Board.

Figure 22. MultiMotor Development Board, #1 of 2

J16 SETTINGS:1-2 AC MOTOR2-3 BLDC MOTOR

GA_H

GA_L

Phase_B

Phase_A

GA_H

GA_L

GB_L

GB_H

GC_L

GC_H

Phase_B

B_H

B_L

C_L

CS1+

CS1-

Vbus_M

Phase_CPhase_BPhase_A

BEMF_A

PD4HSC PD5

Vbus_M ANA4ENABLE PE7

A_LPC7_PWML0A_HPC6_PWMH0

B_HPD0_PWMH1BEMF_A

BEMF_BB_LPD1_PWML1

C_HPD2_PWMH2C_LPD7_PWML2

CS1+BEMF_C

CS1-CS2+CS2-TEMP

HSA PD3

TEMP

GB_L

GB_H

C_H

Phase_A

PD4HSB

BEMF_B BEMF_C

A_H

A_L

Phase_C

VCC_12V

VCC_3v3

VCC_5VM

VCC_3v3

VBUS_B

Q1

IXTY64N055T

1

23

4

C9

0.1uF

TR3210K

Q4

IXTY64N055T

1

23

4

R5150K

R28100 ohm

C4

0.1uF

J2

HDR/PIN 2x15

1357911131517192123252729 30

28262422201816141210

8642

R4150K

R10 22.1 ohm

C1

0.1uF

R35 10 ohm

1 2

Q2

IXTY64

1

23

4

Q5

IXTY64

1

23

4R9 22.1 ohm

C32

0.01uF

SH2

shunt

J6

12

C7

0.1uF, 50V

R24150K

R2 22.1 ohm

D3

BAV19WS

2 1

C31

0.01uF

R3 22.1 ohm

C30

0.01uF

R34 10 ohm

1 2

J4

1 2 3

R2910K

R2210K

D2

BAV19WS

2 1

D1

BAV19WS

2 1

R1 2.2 ohm

U3

NCP5106B

VCC1

IN_HI2

IN_LO3

GND4

DRV_LO5

BRIDGE6

DRV_HI7

VBOOT8

R15 10K

U2

NCP5106B

VCC1

IN_HI2

IN_LO3

GND4

DRV_LO5

BRIDGE6

DRV_HI7

VBOOT8

R20 10K

R19 22.1 ohm

R14 2.2 ohm

U1

NCP5106B

VCC1

IN_HI2

IN_LO3

GND4

DRV_LO5

BRIDGE6

DRV_HI7

VBOOT8

R1710K

R16 22.1 ohm

D9

BAV19WS

2 1

D8

BAV19WS

2 1

R180.100 ohm, 2W

D7

BAV19WS

2 1

C120.1uf

R2710KR26

150KR25150K

R7 2.2 ohm

R3110K

C10

0.1uF

C6

0.1uF

R3010K

+ C3220uF, 50V

R8150K

R12150KR11

150K

C2

0.1uF

R36 10 ohm

1 2

Q7MMBT3904

3

1

2

AN0382 of 29


5V

SHU1-22-3

USE HEATSINK VCC_5VM

VBUS_B

U5

150-5

OUT3

GN

D2

IN1

J12

123

C17

0.1uF+ C15

10uF

12

01-0816


Figure 23. MultiMotor Development Board, #2 of 2

24VDC

GND

GND

12V

EXTERNAL VBUSUP TO 48VDC

holder

NT POSITION EXTERNAL VBUS INTERNAL VBUS

50V

USE HEATSINK

VBUS

VCC_24VVCC_12V

VCC_12V

VBUS

ENABLE

J14

123

J8

123

HS1

TO-220

11

22

D6BAS16

13

2

D51N4007

21

FH1

250V/5x20

12

F1

FUSE/250V/2A

+ C1410uF

12

Q8MMBT3904

31

2

J13

123

J11

123

MIC29

J9

HDR/PIN 1x3

123

J10

123

C16

0.1uF

P1

PJ-003A

1

23

R33

2K

+ C1310uF

12

RL1

JS1A-12V

13

52

U4

MIC29150-12

OUT3

GN

D2

IN1

J7

2 POS

12

SH1

shunt


Appendix B. Flow Charts

Figure 24 presents the flow of the space vector modulation routine.

The Hall sensor for Tacho feedback can be disabled for sensorless V/F control.

Figure 24. Space Vector Modulation Flow Chart

No

Theta <Vector2?

Theta <Vector3?

Theta <Vector4?

Theta <Vector5?

Theta <Vector6?

No

No

No

No

Decompositionroutine:

Calculate T1Calculate T2Calculate T0

Yes

Apply newreference vector

voltages tophaseAphaseBphaseC

NoNoMAIN

Check SpeedDemand

CalculateSetspeed

OrOpen loop speedV/F profiler with

slip controlcalculations

PWMinterrupt?

TachoInterrupt?

Yes

Integrate Speedto obtain rotor

theta

No

Yes

Calculate rotorperiod

Slipcontrol

SVM BLOCK

Note:

AN038201-0816 of 29


Customer Support

To share comments, get your technical questions answered, or report issues you may be experiencing with our products, please visit Zilog’s Technical Support page at http://support.zilog.com.

To learn more about this product, find additional documentation, or to discover other fac-ets about Zilog product offerings, please visit the Zilog Knowledge Base at http://zilog.com/kb or consider participating in the Zilog Forum at http://zilog.com/forum.

This publication is subject to replacement by a later edition. To determine whether a later edition exists, please visit the Zilog website at http://www.zilog.com.

DO NOT USE THIS PRODUCT IN LIFE SUPPORT SYSTEMS.

LIFE SUPPORT POLICY

ZILOG’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS PRIOR WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF ZILOG CORPORATION.

As used herein

Life support devices or systems are devices which (a) are intended for surgical implant into the body, or (b) support or sustain life and failure to perform when properly used in accordance with instructions for use provided in the labeling can be reasonably expected to result in a significant injury to the user. A critical component is any component in a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system or to affect its safety or effectiveness.

Document Disclaimer

©2016 Zilog, Inc. All rights reserved. Information in this publication concerning the devices, applications, or technology described is intended to suggest possible uses and may be superseded. ZILOG, INC. DOES NOT ASSUME LIABILITY FOR OR PROVIDE A REPRESENTATION OF ACCURACY OF THE INFORMATION, DEVICES, OR TECHNOLOGY DESCRIBED IN THIS DOCUMENT. ZILOG ALSO DOES NOT ASSUME LIABILITY FOR INTELLECTUAL PROPERTY INFRINGEMENT RELATED IN ANY MANNER TO USE OF INFORMATION, DEVICES, OR TECHNOLOGY DESCRIBED HEREIN OR OTHERWISE. The information contained within this document has been verified according to the general principles of electrical and mechanical engineering.

ZNEO32! and Z32F128 are trademarks or registered trademarks of Zilog, Inc. All other product or service names are the property of their respective owners.

Warning:

AN038201-0816 of 29

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application note: space vector modulation of a 3-phase ac ...space vector modulation of a 3-phase ac...

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