TI DRV8312和Stellaris MCU三相BLDC马达驱动方案

2012年04月01日 14:27 发布者：1770309616

TI公司的三相BLDC马达驱动套件DK-LM3S-DRV8312采用DRV8312三相马达驱动器和Stellaris MCU,是中电压数字马达控制(DMC)套件,能驱动三相BLDC和永磁同步马达,输入电压最大52.5V,每相连续输出电流最大3.5A,峰值电流6.5A,驱动器开关频率高达500kHz.本文介绍了DRV8312/32主要特性,系统框图,三相应用框图和DRV8312应用案例电路图,以及DK-LM3S-DRV8312主要特性, 马达驱动系统框图, DRV8312评估板电路图和PCB布局图.

The DRV8312/32 are high performance, integrated three phase motor drivers with an advanced protection system.

Because of the low RDS(on) of the power MOSFETs and intelligent gate drive design, the efficiency of these motor drivers can be up to 97%, which enables the use of smaller power supplies and heatsinks, and are good candidates for energy efficient applications.

The DRV8312/32 require two power supplies, one at 12 V for GVDD and VDD, and another up to 50 V for PVDD. The DRV8312/32 can operate at up to 500-kHz switching frequency while still maintain precise control and high efficiency. They also have an innovative protection system safeguarding the device against a wide range of fault conditions that could damage the system.

DRV8312/32主要特性:

High-Efficiency Power Stage (up to 97%) with Low RDS(on) MOSFETs (80 m/uploads/solution/201203/20120331132725732.gif at TJ = 25°C)

Operating Supply Voltage up to 50 V (70 V Absolute Maximum)

DRV8312 (power pad down): up to 3.5 A Continuous Phase Current (6.5 A Peak)

DRV8332 (power pad up): up to 8 A Continuous Phase Current ( 13 A Peak)

Independent Control of Three Phases

PWM Operating Frequency up to 500 kHz

Integrated Self-Protection Circuits Including Undervoltage, Overtemperature, Overload, and Short Circuit

Programmable Cycle-by-Cycle Current Limit Protection

Independent Supply and Ground Pins for Each Half Bridge

Intelligent Gate Drive and Cross Conduction Prevention

No External Snubber or Schottky Diode is Required

DRV8312/32应用:

BLDC Motors

Three Phase Permanent Magnet Synchronous Motors

Inverters

Half Bridge Drivers

Robotic Control Systems

图1.DRV8312/32系统框图

图2.DRV8332三相应用框图

图3.DRV8312三相应用框图

图4.DRV8312应用案例电路图

采用DRV8312和Stellaris MCU的三相BLDC马达驱动套件DK-LM3S-DRV8312

The Medium Voltage Digital Motor Control (DMC) kit (DK-LM3S-DRV8312), shown in Figure 5, provides a great way to learn and experiment with digital control of medium voltage brushless motors to increase efficiency of operation. This document describes the DRV8312 hardware, and explains the functions and locations of jumpers and connectors present on the board.

图5. DK-LM3S-DRV8312外形图(Stellaris®版本)

图6.DRV8312基板外形图

DK-LM3S-DRV8312主要特性:

• Three-Phase Power Stage, DRV8312 capable of driving three-phase brushless DC motors and Permanent Magnet Synchronous Motors 52.5 V DC max input voltage

6.5 A peak with a 3.5 A max continuous output current per phase Up to 500 khz driver switching frequency

• 24 V switching power supply with on-board regulation for powering other analog and digital circuitry

• Isolated CAN and SPI communication (controlCARD support-dependent)

• Closed-loop digital control with feedback using the Stellaris microcontroller’s on-chip PWM and ADC peripherals

JTAG connector for external emulators (not used with Stellaris microcontrollers) Quadrature Encoder Interface (QEI) available for speed and position measurement Hall-Sensor Interface for sensored three-phase motor control

High precision, low-side current sensing using the Stellaris microcontroller’s high-performance ADC, Texas Instruments’ OPA365A high-speed op-amps, and Texas Instruments’ REF3025 high precision voltage reference chip

Three PWM DACs generated by low-pass filtering the PWM signals to observe the system variables on an oscilloscope to enable easy debug of control algorithms

Over-current protection on the inverter stage, DRV8312