Analysis of three-phase BLDC motor and sharing of two popular development boards

The growing popularity of brushless DC (BLDC) motors is due to the use of electronic commutation. This replaces the traditional mechanism of brushes rubbing against a commutator to energize the windings in the DC motor's armature. While BLDC motors can be built in different physical configurations, these can be configured as single-phase, two-phase, or three-phase motors, depending on the stator windings.

Among them, single-phase induction motors and single-phase brushless DC (BLDC) motors have been around for many years and are widely deployed in household appliances (such as refrigerators), industrial air conditioning systems, and many other applications, providing a relatively cheap way to drive fans. Although the material cost of such applications is very low, this is the wrong way to save money, because the inefficient operation of the motors generally means that the related power consumption will remain high, so the electricity bill will be higher.

In addition, the considerable noise generated by single-phase BLDC motors also has to be considered. Stronger international environmental legislation and more consumers becoming more energy efficient are driving the trend away from fixed-speed single-phase induction motors and toward adjustable-speed synchronous motors.

Based on this, precision three-phase BLDC motors are becoming more and more attractive in today's era of energy conservation. These components do not require a mechanical commutator (which is a prerequisite for brushed motors), so the machinery is not easy to wear, resulting in higher reliability, longer service life, and higher energy efficiency levels. Therefore, the most commonly used is the three-phase BLDC motor with a permanent magnet rotor.

Next, we will introduce two popular development boards from Fengqi.

FT8215Q Development Board Introduction

FT8215Q is a three-phase, sensorless FOC controlled brushless DC motor driver IC with built-in driver MOS. It supports 5V-18V DC power input and can support a maximum operating current of 2A.

The FT8215Q development board is a special test board designed for developers. The development board has power terminals, U/V/W terminals, emulator sockets, and various functional interfaces. Developers can simulate and debug motors and communication IC burning, as well as test PWM/VSP speed regulation, forward and reverse control, FG speed measurement and other functions.

The FT8215Q development kit includes a development board, emulator, debugging manual, data sheet, debugging software, schematic diagram, etc., providing developers with a stable design reference and a complete software development environment, which can effectively help developers improve development efficiency, shorten development cycle, optimize design quality, and accelerate product development and time to market.

Figure 1: FT8215Q development board physical picture

FT8215Q development board pin functions

Table 1: FT8215Q development board pin function description

FT8215Q development board hardware wiring

Figure 2: FT8215Q development board hardware wiring diagram

FT8215Q Development Board Schematic

Figure 3: Schematic diagram of the FT8215Q development board

FT8215Q Development Board PCB

Figure 4: FT8215Q development board layout

Figure 5: FT8215Q development board PCB diagram

FT8215Q chip package

FT8215Q is a QFN24 package with a length and width of 4mm and a thickness of 0.75mm. The chip is highly integrated, with a small package size, few peripheral devices, high drive efficiency, low noise, small torque ripple and low cost.

FT8215Q can realize slow start, speed control, multiple speed regulation modes, multiple protection functions, etc. It supports pre-positioning/initial position detection, supports starting with forward and reverse winds, the chip can be burned multiple times, and is suitable for FOC sinusoidal wave drive control of sensorless three-phase motors.

Figure 6: FT8215 QFN24 (4mm4mm0.75mm)

FT8215Q Functional Block Diagram

FT8215Q is a highly integrated motor control module. It has a built-in driver MOS and few peripheral components. The chip has a built-in EEPROM module that can configure motor parameters, FOC parameters, startup and speed control parameters, etc.

FT8215Q has multiple built-in functional modules: system clock (OSC), ADC sampling, I2C communication, 5V voltage regulation (LDO), current sampling (VScaler), over-current protection (Over Current), over-temperature protection (Thermal), etc. The external pins include U/V/W drive output, SPEED/APSEED speed regulation, FG output, forward and reverse DIR control, etc.

Figure 7: FT8215Q functional block diagram

FT8215Q Functional Description

Table 2: FT8215Q function description

Purchase link of Fengqi Technology FT8215Q development board:

https://www.hqchip.com/p/FT8215Q.html

FT8132Q Development Board Introduction

Based on the test board provided by FT8132Q three-phase motor control IC for developers, MOSFET drive circuits, various current and voltage detection circuits, HALL input circuits, and various functional interface circuits are designed. It can realize the sensorless FOC drive, sensory FOC drive, and sensory SVPWM drive of three-phase motors, support constant speed, constant current, constant power, and voltage loop control modes, support analog voltage, PWM, I2C, CLOCK to adjust the motor speed, support HALL, BEMF detection, and can also realize real-time feedback of speed and control of motors, as well as preliminary research on the development of various application solutions;

The FT8132Q development test board supports 5V-28V power supply voltage, maximum current 10A design, supports analog voltage, PWM, I2C, CLOCK speed regulation, FG/RD signal feedback, etc. The dedicated control IC of Fengqi Technology is highly integrated. Developers only need to use FT8132Q+MOS as the basis to complete the design of motor control related products; at the same time, developers can use the supporting GUI debugging software to directly set parameters and run without programming, shortening the product development cycle and simplifying the product design process;

The development kit provides a dedicated IC user manual, PDF schematics, host computer GUI debugging interface, emulator, etc., providing developers with a stable design reference and a complete software development environment, which can effectively help developers improve development efficiency, shorten development cycle, optimize design quality, and accelerate product development and time to market.

Figure 1: FT8132Q development board

FT8132Q development board basic parameters

Table 1

Figure 2: 3D rendering of the FT8132Q development board

Figure 3: Rendering of the FT8132Q development board

Figure 4: FT8132Q development board schematic

Figure 5: FT8132Q development board functional interface diagram

FT8132 chip introduction

FT8132 is a three-phase brushless DC motor driver IC with built-in Pre-driver. The chip is highly integrated, with few peripheral components, low motor noise and small torque pulsation. The GUI can configure customer motor parameters, startup and speed regulation methods, and store them in the built-in EEPROM. The speed regulation interface can select analog voltage, PWM, I2C, CLOCK to adjust the motor speed. The integrated speed indication function can read the motor speed in real time through the FG pin or I2C interface. The control mode can select constant speed, constant current, constant power and voltage loop control. It integrates multiple protection modes such as overcurrent, undervoltage, overvoltage, external overtemperature, internal overtemperature, stall, phase loss, Hall abnormality, etc., and the sleep current is about 50μA.

Figure 6: FT8132Q sensorless functional block diagram

Figure 7: FT8132Q sensor functional block diagram

Main parameters of FT8132 chip

Table 2