User Guide

6 of 38

2021-01-29

The reference board at a glance

User guide for REF-22K-GPD-INV-EASY3B

A reference design for a general purpose drive

for controlling the speed and torque of the motor. During braking or deceleration of the motor, energy is

transferred back into the DC-link capacitor increasing the DC bus voltage. Therefore, a brake chopper is

included that absorbs this energy by switching an external brake resistor across the DC bus capacitors. The

three-phase input rectifier, the six pack as well as the brake chopper are all included in one power module, the

Easy3B IGBT FP100R12W3T7_B11. All IGBTs are switched using EICE™ drivers, the 1ED3131MC12H. The isolation

coordination details of the unit can be found in Section 2.2.2.

The current measurement of the three-phase output current is done with TLI4971-A120T5 current sensors. The

current signals are used for the motor control; additionally, these sensors are used to detect an external short

circuit for the IGBT’s. To protect the module against an internal short circuit, a fourth current sensor is

integrated between the DC-link capacitor and the IGBT module.

The auxiliary voltage for the inverter is generated with a DC/DC switch mode power supply (SMPS) converter.

The CoolSiC™-MOSFET IMBF170R1K0M1 is used in a flyback topology. More details about the flyback SMPS are

listed in Section 2.2.4.

The reference inverter uses two microcontrollers; one for control and one for communication. For control the

XMC4800-F144F2048 is used, for communication the XMC4300-F100K256 AA is designed in. Both

microcontrollers communicate via an UART interface. The communication microcontroller allows the inverter

to be controlled via a touch-screen or a PC-GUI. More details on the communication interface can be found in

Section 2.2.1.

A simplified block diagram is shown in Figure 2. The block diagram shows the main components of the boards,

the DC/DC SMPS converter, the low-voltage interface board (SELV board), high-voltage logic board (FELV

board), the IGBT module incl. the gate driver IC, and the output phase current measurement. Also the main

Infineon components used in the specific blocks are listed in the diagram.

-_

high voltage

logic board

(FELV board)

low voltage

interface board

(SELV board)

rectifier

DC/DC converter

EMI filter

six pack

3Ph

Motor

user

interfaces

front

display

sensor

interfaces

3 phase

AC Input

3 phase

AC output

brake chopper

DC-Link

brake resistor

pre charge

resistor/relay

FP100R12W3T7_B11

1ED3131MC12H

curr

3 ph

TLI4971

IMBF170R1K0M1

XMC4800

XMC4300

Figure 2

Simplified block diagram of the inverter