5 Introduction

Brush Less DC (BLDC) motors are fitted with digital Hall sensors that provides rotor information for commutation of phases. The Hall sensors are used for block commutation of BLDC phases and provide rotor position with poor resolution. Block commutation has drawbacks like torque ripple and reduced efficiency. It is proven that vector control gives the best performance for the BLDC motor in terms of efficiency and torque ripple. However, because of poor angle resolution Hall sensors cannot be used for vector control. The Hall interface block generates high resolution angle from the low resolution angle provided by Hall sensors. It also computes the speed of the motor based on Hall signals.

Summary

The following table provides a summary of the Hall Interface characteristics.

Table 5-1. Hall Interface Characteristics
Core VersionThis document applies to Hall Interface v4.2.
Supported Device Families
  • PolarFire® SoC
  • PolarFire
  • RTG4™
  • IGLOO® 2
  • SmartFusion® 2
Supported Tool FlowRequires Libero® SoC v11.8 or later releases.
LicensingComplete encrypted RTL code is provided for the core, enabling the core to be instantiated with SmartDesign. Simulation, Synthesis, and Layout are performed with Libero software. Hall Interface is licensed with encrypted RTL that must be purchased separately. For more information, see Hall Interface.

Features

Hall Interface has the following key features:

  • Computes the raw angle from the hall inputs
  • Computes the filtered speed from the angle

Implementation of IP Core in Libero Design Suite

IP core must be installed to the IP Catalog of the Libero SoC software. This is done automatically through the IP Catalog update function in the Libero SoC software, or the IP core is manually downloaded from the catalog. Once the IP core is installed in the Libero SoC software IP Catalog, the core is configured, generated, and instantiated within the SmartDesign tool for inclusion in the Libero project list.