23 February 2022
EPC adds 3-phase BLDC motor drive inverter for e-bikes, drones and robotics
Efficient Power Conversion Corp (EPC) of El Segundo, CA, USA – which makes enhancement-mode gallium nitride on silicon (eGaN) power field-effect transistors (FETs) and integrated circuits for power management applications – has announced the availability of the EPC9167, a 3-phase BLDC (brushless DC) motor drive inverter using the EPC2065 eGaN FET. It operates from an input supply voltage of 14-60V (nominal 48V) and has two configurations – a standard unit and a high-current version:
- The EPC9167 standard reference design board is a 3-phase BLDC motor drive inverter board featuring the EPC2065 eGaN FET rated at 3.6mΩ maximum RDS(on), 80V maximum device voltage. This standard configuration uses single FETs for each switch position and can deliver up to 20ARMS maximum output current.
- The EPC9167HC high-current configuration version of the reference design uses two paralleled FETs per switch position with the ability to deliver up to 42Apk (30ARMS) maximum output current.
Both versions contain all the necessary critical function circuits to support a complete motor drive inverter including gate drivers, regulated auxiliary power rails for housekeeping supplies, voltage, and temperature sense, accurate current sense, and protection functions. The boards also feature ST Microelectronics’ STDRIVEG600 smart motor drive GaN half-bridge driver.
The EPC9167 boards measure just 130mm x 100mm (including connector). The boards can also be configured for multi-phase DC–DC conversion and support both phase and leg shunt current sensing.
Benefits of a GaN-based motor drive with these reference design boards are said to include lower distortion for lower acoustic noise, lower current ripple for reduced magnetic loss, lower torque ripple for improved precision, and lower filtering for lower cost. The EPC9167 boards’ lower weight and size enable incorporation of the drive into the motor housing and supports low-inductance, higher-power-density motors.
EPC provides full demonstration kits, which include interface boards that connect the inverter board to the controller board development tool for fast prototyping that reduce design cycle times.
The default setting for the GaN-based motor drive kit is 100kHz switching frequency and 14ns deadtime. While the kit is designed to be programmed for different frequencies and deadtimes, operation at high frequency around 100kHz allows for the elimination of electrolytic capacitors and the use of lower capacitance, and reduce the motor losses. Operating the boards with very small deadtime of around 14ns allows higher torque per ampere. The joint effect is to improve inverter and motor system efficiency of more than 7% versus a silicon MOSFET solution which typically operates at 20kHz and 500ns deadtime.
“GaN-based inverters increase motor efficiency while reducing their cost and delivering the same performance as an expensive motor using a silicon MOSFET-based inverter,” says CEO Alex Lidow. “This enables motor systems that are smaller, lighter, less noisy, have more torque, more range, and greater precision.”
The EPC9167 reference design board is priced at $611.58 and the EPC9167HC reference design is priced at $678.78. Both are available for immediate delivery from distributor Digi-KeyCorp.