An automotive motor control solution-IPM

IPM (Intelligent Power Module) has built-in drive and protection circuits, making the system hardware circuit simpler and more reliable. It not only shortens the system development cycle, but also improves the self-protection capability under faults. IPM will be the mainstream solution for motor control in the future .

With the annual growth of automobiles, the control of the electric parts of automobiles has also increased, such as automobile high-voltage auxiliary motors, compressors, oil pumps, water pumps, turbochargers, various fans, etc. Although the traditional discrete type can also meet the needs, the integration is not high, the parameter selection is cumbersome, the pre-drive and drive are combined, and the overall design is relatively complex. ZLG has launched a three-phase 650V 30A/40A/50A IPM motor control solution for automobiles based on ON's intelligent power module , as shown in Figure 1. Compared with ordinary IGBTs, IPM has been further improved in system performance and reliability.

Figure 1 Motor control solution

1. Introduction of Solution Chip

The figure below is ON's 650V intelligent power module for automobiles. It is divided into 30A, 40A, and 50A current levels. This article mainly introduces the 50A version. IPM is an advanced automotive SPM module that provides full-featured, high-performance inverter output for hybrid and electric vehicles. The module integrates a built-in IGBT optimized gate drive to minimize EMI and losses, while also providing a variety of in-module protection functions, including undervoltage lockout, overcurrent shutdown, driver IC thermal monitoring, and fault reporting. The built-in high-speed HVIC requires only one power supply voltage and converts the input logic level gate input into the high-voltage, high-current drive signal required to properly drive the IGBT inside the module. The internal structure is shown in Figure 2.

Figure 2 IPM internal block diagram 

2. IPM has the following characteristics:

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• Available in automotive SPM 27-pin DIP package;

• Automotive-grade chips (AEC-Q100/101 and LV 324);

• 650 V / 50 A three-phase IGBT inverter with integrated gate driver and protection;

• Has stable EMI performance;

• Using the excellent thermal resistance of AIN DBC substrate, the heat dissipation efficiency is higher;

• Built-in LVIC temperature sensor to save BOM cost;

• Heatsink Isolation Rating: 2500 Vrms / 1 min;

• Lead-free and RoHS compliant;

3. Motor Control Solution Design

The solution adopts ON flyback topology, high-voltage and low-voltage isolation, pre-driver and IGBT integrated in IPM, and combines MCU to realize over-temperature, over-voltage/under-voltage, over-current and other protection functions. The solution block diagram is shown in Figure 3. In addition, there is a special visual online debugging and monitoring software that can quickly adjust and optimize motor parameters, automotive digital and motor control library, providing you with product-level, high-performance solutions.

Figure 3 Solution diagram 

4. The solution has the following characteristics:

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• Flyback switching power supply to achieve high voltage and low voltage isolation;

• High voltage overvoltage/undervoltage detection;

• High voltage overcurrent and short circuit protection function;

• IPM internal linear temperature sensor;

• IPM error output;

• Voltage and current sampling to achieve joint protection of device safety by software and hardware;

• Isolate CAN communication function, complete CAN protocol interface, support CAN speed regulation;

• Improved FOC algorithm to reduce startup time and increase maximum speed;

• Ramp-down strategy for stopping the motor.