Designing Smarter Motor Drive Systems. Wison Zuo Application Engineer Motor Driver Business Unit Texas Instruments

Transcription

1 Designing Smarter Motor Drive Systems Wison Zuo Application Engineer Motor Driver Business Unit Texas Instruments 1

2 Electric Motor System Overview Motor Control Gate Driver Power Stage Microcontroller Manages the control system, motor commutation, driver settings, fault handling IGBT or MOSFET gate driver Level shifts logic control signals Power stage fault detection and handling IGBT or power MOSFET Interface main power rail to electric motor Often in half-bridge, H- bridge, or inverter configuration Feedback Signals from motor Position, torque, voltage, current 2

3 Designing a Smarter Motor Drive System We now have a basic understanding of the motor drive system, right? But there are many pitfalls to avoid, knobs to adjust, timings to tune, circuits to implement and debug. + V GATE V BST DRVxxxxx R SOURCE OC Detect V DS Monitor + - V SUPPLY + V SUPPLY INH Q: Are there any tools that can make the process simpler, more efficient? V GATE C BST R SINK D SINK R PD V DS Monitor To Load A: Yes, the IC has given the ability to integrate this system into a single chip and even add additional features outside of the typical motor drive system INL OC Detect R SOURCE R SINK D SINK R PD + - TI Smart Gate Drivers 3

4 Designing a Smarter Motor Drive System Q: What do TI DRV gate drivers do? DRV8305 A: See this section and Application Report for more details Challenge: Designing multiple power supplies for the motor drive system Solution: TI gate drivers are single supply devices that generate all the necessary voltages for the motor drive system From the motor supply (PVDD) the device (DRV8305 generates the highside (VCPH) and low-side (VCP_LSD) gate driver supplies, the analog (AVDD) and digital (DVDD) circuitry supplies, and an has uncommitted LDO (VREG) for an external MCU 4

5 Designing a Smarter Motor Drive System Gate driver supplies support full enhancement (10 V) of high-side and low-side n-channel power MOSFETs Supports logic level and standard level MOSFETs High-side gate drive supply Low-side gate drive supply DRV8305 5

6 Designing a Smarter Motor Drive System Challenge: Proper dead time insertion and cross conduction (shoot-through) protection Solution: Incorporate automatic handshaking so that the optimal dead time is utilized regardless of slew rate, voltage, MOSFET, and temperature The handshake is a multi step process that ensures that optimal dead time is utilized and cross conduction does not occur V GS Monitors V SUPPLY 1. Receive signal to switch from high to low-side MOSFET 2. Disable high-side MOSFET and monitor the V GS to determine when the MOSFET is disabled Internal Handshake & Dead Time Insertion Insert any dead time specified by the external controller and then enable the low-side MOSFET - 6

7 Designing a Smarter Motor Drive System Challenge: Reduce voltage transient on MOSFET gate due to dv/dt coupling Solution: Enable a strong current sink on the MOSFET opposite of the slewing MOSFET Gate Driver OFF -> ON I SOURCE V SUPPLY As outlined earlier when the MOSFET enables and the switch-node voltage slews, charge can couple into the gate of the opposite MOSFET through a parasitic capacitance V DS C GD By providing a strong current pulldown on the opposite MOSFET during the slew, the gate driver can reduce the parasitic voltage seen at the opposite gate Gate Driver V GS I PULLDOWN 7

8 Designing a Smarter Motor Drive System Challenge: Protect the system against overcurrent events related to motor stall, short circuits, and component failures Drain Solution: Incorporate V DS monitors that can measure the voltage between the MOSFET drain and source pins OC Detect Gate Drain Current V DS Trip Point Source Can take advantage of the fact that the MOSFET acts as a fixed resistance (with variation for temperature) at a given V GS (think sense resistor) The driver uses monitors for both the high and low-side MOSFET to determine if an overcurrent has occurred Current trip point can be set through device registers or external resistor 8

9 Designing a Smarter Motor Drive System Challenge: Adjust MOSFET slew rate in order to optimize switching performance Solution: Provide simple method to adjust slew rate by creating gate drivers with variable current settings Gate Drive (Internal) V GATE V GATE V GATE 12.5 ma 25 ma 100 ma OFF ON OFF OFF MOSFET (External) V GATE V DRAIN 150 ma I SOURCE V DD 25 ma 50 ma 200 ma OFF OFF OFF OFF 300 ma Gate Drive R SOURCE R SINK RPULLDOWN Adjustable gate drivers remove the need for multiple external components traditionally used for slew adjustment Allows for experimentation of different slew rates with the change of a register bit by the external controller 9

10 Designing a Smarter Motor Drive System Example of slew rate adjustment with the DRV ma 20 ma 30 ma 40 ma 50 ma 60 ma 70 ma V DRAIN V DS + MOSFET V DS I GATE V DS - Persistence capture to obtain slew rate with different gate drive settings (10-70 ma) 10

11 Designing a Smarter Motor Drive System Examining difference between 20 ma and 70 ma settings Miller region Gate current (20 ma) Gate current (70 ma) MOSFET V DS MOSFET V GS I GATE 20 ma 70 ma V DRAIN V DS + Enable received, start gate drive Remaining gate charge Miller region Remaining gate charge I GATE V GS + V GS - V DS - 11

12 Designing a Smarter Motor Drive System DRV8305 DVDD AVDD VCP_LSD CP2H CP2L CP1H CP1L Challenge: Minimize board area and component count DRV8305 triple half-bridge gate driver WAKE DVDD DVDD LDO AVDD VREG AVDD LDO VCP_LSD Low Side Gate Drive LDO High Side Gate Drive 2-Stage Charge Pump VCPH VCPH PVDD PVDD Solution: Provide single IC that replaces functionality of traditional gate drive architectures VREG/VREF PWRGD EN_GATE INH_A INL_A VREG LDO + VDS - + VDS - VDRAIN VCPH HS VCP_LSD LS Phase A Pre-Driver VDRAIN VDRAIN GH_A SH_A GL_A SL_A PVDD INH_B INL_B INH_C Digital Inputs and Outputs Core Logic VDRAIN VCPH + HS VDS - VCP_LSD GH_B SH_B INL_C Control + VDS - LS GL_B SL_B nfault Configuration Phase B Pre-Driver PVDD VDRAIN VCPH SCLK Timing + VDS - HS GH_C SH_C nscs SDI SPI Protection + VDS - VCP_LSD LS GL_C SL_C x3 SDO SO1 Thermal Sensor Voltage Monitoring VREG Ref/k Phase C Pre-Driver AVDD Current Sense Amplifier 1 SN1 SP1 SO2 SO3 VREG Ref/k AVDD Current Sense Amplifier 2 SN2 SP2 VREG Ref/k AVDD Current Sense Amplifier 3 SN3 SP3 GND GND PowerPAD 12

13 Designing a Smarter Motor Drive System TI s DRV Gate Driver Family DRV8301/2/3: 6 to 60 V Brushless DC Motor Gate Driver DR8307/8: 8.5 to 32 V Brushless DC Motor Controller DRV8711: 8 to 52 V Stepper Motor Gate Driver DRV8701: 5.9 to 45 V Brushed DC Motor Gate Driver DRV8305: 4.4 to 45 V Brushless DC Motor Gate Driver DRV8305-Q1: 4.4 to 45 V Automotive Brushless DC Motor Gate Driver 13

14 MDBU BLDC/BDC Solution in Robot BLDC Electronic Speed Control (Per Propeller): MSP430 C2000 DRV8301/2/3 6 to 60 V BLDC gate driver w/ 2 current DRV8305 shunt amplifiers 4.4 to 45 V BLDC gate driver w/ 3 current shunt amplifiers NexFET BLDC Motor DRV9x BLDC gate driver w/ integrated MSP430 NexFET BLDC Motor Solution 1 Solution 2 BLDC Control (Per Axis): MSP430 DRV to 60V 2.5A Brushless DC Motor Driver DRV to 38 V Digital Latch Hall Effect Sensor BLDC Motor MSP430 DRV to 11V 1.8A Dual ½ Bridge Motor Driver DRV to 38 V Digital Latch Hall Effect Sensor x2 BLDC Motor Solution 1 Solution 2 BDC 1S to 2S LiPo Electronic Speed Control (Per 2x Propeller): MSP430 DRV to 5.5 V, 5 A, Dual ½ Bridge Motor Driver BDC Motor BDC Motor MSP430 DRV to 11 V, 1.5 A, Dual H-Bridge Motor Driver BDC Motor BDC Motor Solution 1 Solution 2

15 New DRV8x for Brushed, Stepper 15

16 Brushed, Stepper Driver DRV8880 (8881, 8885) Supper easy to use; AutoTune for Decay; Supper low noise; Supper smooth running DRV8870 (8871, 8872) Supper easy to use; Current regulation; 8-pin; Rsense Free for DRV

17 DRV8880: Great AutoTune feature! Get the following waveform the first time you start the stepper in 1 min 17

18 TI Designs Providing comprehensive design examples 18

19 TI Design TIDA to 30 V, 15 A, High Performance Brushless DC Propeller Controller Overview: Putting theory into practice The TIDA reference design is a 4.4 to 30 V brushless DC motor controller for high power propeller, fan, and pump applications. It uses the Texas Instrument s DRV8305 brushless DC motor gate driver, CSD17573Q5B 30V NexFET TM power MOSFETs, TPD4E05U06 TVS protection IC, C2000 motor control MCU, and LMR V buck converter. It utilizes InstaSPIN TM -FOC for sensorless field oriented motor control and commands the motor speed through an external reference signal from a central controller. This design is focused on demonstrating a highly efficient and high power BLDC motor system. Features: 4.4 V to 30 V input voltage range 15 A RMS, 23 A peak output current capability Small form factor (L x W): 2.2 x 1.0 Speed control with single reference signal Onboard 3.3 V, 0.6 A buck converter Motor control through InstaSPIN-FOC TM sensorless field oriented control Wide array of system protection features including MOSFET V DS overcurrent and supply undervoltage protection Visit: ti.com/tidesigns Part number:tida Complete BLDC motor controller in 2.2 x 1.0 form factor 19

20 TI Design TIDA to 30 V, 15 A, High Performance Brushless DC Propeller Controller Visit: ti.com/tidesigns Designed for compact (space constrained), high efficiency propeller applications Part number:tida TIDA Block Diagram 20

21 TI Design TIDA to 30 V, 15 A, High Performance Brushless DC Propeller Controller Motor Control Gate Driver Power Stage TIDA Microcontroller Manages the control system, motor commutation, driver settings, fault handling IGBT or MOSFET gate driver Level shifts logic control signals Power stage fault detection and handling IGBT or power MOSFET Interface main power rail to electric motor Often in half-bridge, H- bridge, or inverter configuration Feedback Signals from motor Position, torque, voltage, current 21

22 TI Design TIDA to 30 V, 15 A, High Performance Brushless DC Propeller Controller Motor ramping from 0 RPM to 7000 RPM in less than 1.5s 22

23 TI Design TIDA to 24 V, 27 A, High Power Brushed DC Motor Reference Design Overview: Putting theory into practice The TIDA reference design is a 12 to 24 V brushed DC motor controller for power tool, pump, fan, and robotics applications. It uses the Texas Instruments DRV8701 brushed DC motor gate driver, CSD18540Q5B 60 V NexFET TM power MOSFETs, LMT86 temperature sensor, and MSP430G2553 microcontroller. The reference design takes advantage of the high efficiency NexFET power MOSFET and DRV8701 to deliver peak performance with no external heatsinking. The system is managed by the MSP430G2553 which monitors feedback signals from the motor, motor driver, and remaining system. Visit: ti.com/tidesigns Part number:tida Features: 12 V to 24 V input voltage range 27 A RMS output current capability Small form factor (L x W): 76 mm x 38 mm User configurable gate drive current Integrated 3.3 V, 30 ma LDO Integrated motor current regulator for startup and stall currents Wide array of system protection features including MOSFET V DS overcurrent and supply undervoltage protection 23

24 TI Design TIDA to 24 V, 27 A, High Power Brushed DC Motor Reference Design Visit: ti.com/tidesigns Part number:tida TIDA Block Diagram 24

25 TI Design TIDA to 24 V, 27 A, High Power Brushed DC Motor Reference Design 25 A to Motor 27 A to Motor 25

26 TI EVMs Enabling Customer Designs All Texas Instrument s DRV motor driver and gate drivers are supported by comprehensive evaluation kits (EVM) Allow customer to connect their motor and power supply and instantly begin evaluating the DRV device with a simple GUI or hardware controls 26

27 TI EVMs Enabling Customer Designs Also, recently added to the TI BoosterPack lineup.ti Motor Drive BoosterPacks Support for main DC motor types (brushless, brushed, stepper) Compatible with TI MCU LaunchPads BOOSTXL-DRV8301 BOOST-DRV8848 New BOOST-DRV8711 BOOSTXL-DRV8305EVM 27

28 Integrate Motor Control Solution 28

29 Architectural Benefits Discrete Solution Software and hardware design Significant board space Higher component count Control (MCU, DSP, FPGA ) Gate Drive Current Feedback Protection FETs DRV10x Fixed Function Single chip solution Smallest board space Code-free development State Machine Controller + Driver Gate Drive Feedback Protection FETs 29

30 DRV10x Fixed Function Motor Controller Overview Family Feature Overview Digital Core BLDC motor control state machine Hall-sensored & sensorless True sine, pseudo-sine & enhanced trap Configurable for optimal performance Motor Drive Stage Gate driver w/ internal charge pump Integrated half-bridges Start-up / stall current limit (no current sense resistor required) Target Applications & Customer Benefits Battery/System Voltage Speed DRV10x Fixed Function Motor Controller M Motor Feedback Further Integration PWM interface Configuration interface (I2C or hardware) Hall comparator for Hall-sensored devices BEMF handling for sensorless devices Power management Full suite of protection Target Applications Appliances White goods Small appliances (air purifiers, vacuums, pedestal fans etc.) Fan / pump motor modules Personal & enterprise compute Laptops Servers General purpose BLDC motor module Customer Benefits Optimal efficiency, ultra-low acoustic noise, minimal vibration Code free tunability Minimum design efforts Highly reliable

31 DRV10x Fixed Function BLDC Roadmap Trap Sine Trap Sine Sensored Sensorless DRV to 5.5V BLDC controller w/ external config DRV to 5.5V BLDC controller DRV to 5.5V 150 BLDC controller DRV to 18V configurable BLDC controller DRV to 16V 150 BLDC controller DRV to 18V configurable BLDC controller DRV10983-Q1 Up to 45V BLDC Controller DRV to 28V configurable BLDC controller Up to 6V Up to 20V Up to 50V 31 Production Sampling Development Concept

32 DRV V, 3-phase Sensorless BLDC Motor Driver Features 3-Phase Brushless DC Motor Controller & Driver Supply voltage: Output Current: RDSON (LS + HS): 180 sensor-less control 8 to 28V 2A RMS / 3A Peak 250mΩ Highly configurable spin up profiles Analog, PWM, and I2C control I/F options On-chip, 100mA, 5V/3V step down buck FG output provides TACH feedback Ultra-low 180uA sleep current available on DRV10983Z Fully protected with detailed fault reporting Short Circuit / Open load Rotor Lock / Stall Applications Thermal / UVLO / Shoot-through Cooling Supply fans, Pumping ceiling fans, Overvoltage blowers Pumps 1K Pricing: In Production DRV10983: $1.95 DRV10983Z: $ x 6.4mm, 24-pin TSSOP package Benefits Highly Integrated Integrates VREG, Control, Gate drive, and FETs No hall sensors or sense resistor / minimal BOM Ultra Quiet Operation Patented 180 sinusoidal control algorithm Customize spin up profile for quiet & reliable start-up Code Free Tunability Tune motor for optimal efficiency, performance, and reliable start up. No MCU codding required. Fully Protected Advanced on-chip protection reduces design complexity and enables higher system reliability. Direction Speed FG Output I 2 C +8 to 28V DRV10983 Fan FAN/PUMP / Pump Controller 100mA Buck M

33 DRV10983: +24V 3-phase Sensorless BLDC Motor Driver 180 Sinusoidal Sensorless Control Programmable Spin Up Profiles Start Up Options: IPD, Align and Go, Forward & Reverse Silent Startup / Acceleration Adjustable Commutation Angle 8 to 28V Supply Operating Range AVS Over-Voltage Protection SDA SCL SW VREG SWGND V3P3 V1P8 GND SPEED DIR U V W I2C communication 3.3/5V regulator V/I sensor 3.3V LDO 1.8V LDO Oscillator Bandgap PWM & Analog speed control Lock Over Current Thermal UVLO ADC Register Logic Core GND VCP Gate driver VCP Gate driver VCP Gate driver EEPROM Charge Pump VCC PGND VCC PGND VCC FG VCC VCP CPP CPN U V W PGND 2A RMS 3A Peak Analog, PWM, Serial Speed Ctrl Tach Output for Closed-Loop Speed Control Advanced Rotor Lock Protection OCP, thermal, UVLO, Shootthrough,& Open Load Protection 3.5mA Standby (DRV10983) 180uA Sleep (DRV10983Z)

34 DRV10983: +24V 3-phase Sensorless BLDC Motor Driver +8 to 28V : AVS Protects against Supply Pumping Optional 3.3/5V 100mA Step Down Buck VCC 10µF 3.3V/5V 1µF 1µF 47µH Interface to microcontroller 0.1µF 0.1µF VCP CPP CPN SW SWGND VREG V1P8 GND V3P3 SCL SDA FG VCC VCC W W V V U U PGND PGND DIR SPEED µF M 2A RMS 3A Peak Serial, PWM, or Analog Speed Control + FG Pin Minimal BOM Count No Sense Resistor

35 DRV5000 Hall Effect Sensors

36 DRV5013, DRV5023, DRV5033, DRV5053 Magnetic Hall Effect sensors for industrial and automotive applications Features 2.5V to 38V operating supply voltage Tolerates -22V and 40V reverse battery and load dump AEC-Q100 Grade 0, Grade 1, and Industrial options 175 C max operating junction temperature Low 2.7mA typical I CC Fast 35 µs power-on time Fast 13 µs propagation delay Two package options: SOT-23 and TO-92 Benefits Most robust operating voltage range in the industry, to withstand transient voltage spikes and reversed-battery. Suitable for the harshest automotive Grade 0 environments. Simple, low-cost, robust, easy motion sensor design Highly reliable magnetic sensors that are immune to wear, environmental contaminants, dirt, and RF noise. Minimal magnetic threshold change across temperature. Pins are fully protected from shorts. Applications Automotive control systems and body closure Brushless DC Motor commutation Power tools Contactless position sensing, limit switches Flow meters Robotics, industrial automation In Production New sensitivity options sampling soon 1k Pricing: $0.27 SOT-23 TO-92

37 DRV5013, DRV5023, DRV5033, DRV5053 Typical Magnetic Sensitivity DRV5013 Digital Latch FA AD AG BC 1.3 mt 2.7 mt 6 mt 12 mt DRV5023 Digital Unipolar Switch FA FI AJ BI * 3.5 mt 3.5 mt 6.9 mt 14.5 mt DRV5033 Digital Omnipolar Switch FA AJ 3.5 mt 6.9 mt DRV5053 Analog Bipolar OA CA PA EA RA VA -11 mv/mt 23 mv/mt -23 mv/mt 45 mv/mt -45 mv/mt -90 mv/mt 37 *Inverted output

38 Questions Wilson Zuo M: Q: Any questions? O:

39 Thanks!!! 39