Texas Instruments Hybrid/Electric Vehicle Charger Solutions

Energy Efficiency For more than 20 years, TI has been committed to helping customers design high-performance power conversion products to meet stringent energy efficiency specifications. TI can help customers quickly occupy the market through advantageous energy-saving designs. TI provides point-of-load DC/DC converters, offline power supplies and digital power management solutions, helping customers meet low standby power requirements through various light-load efficiency improvement functions. As energy-saving and environmentally friendly new energy vehicles - hybrid vehicles/pure electric vehicles. TI has also been committed to providing customers with more complete and excellent automotive solutions. Here, Electronic Enthusiasts Network has brought you several solutions of TI in hybrid vehicles/pure electric vehicles for your reference.

E-Bike Solutions from Texas Instruments (TI)

Design Considerations

Electric bicycles are becoming an increasingly popular choice for people who live close to work or who are looking for an alternative to more expensive motor-controlled transportation. As battery and motor technology advance rapidly, the speed and range of electric bicycles are also increasing. Electric bicycles can use a variety of components based on expected cost and design complexity.

The kernel subsystems include:

Controller:

Typically includes detection, A/D conversion, and output comparison components. Ultra-low power microcontrollers can be used for low-end systems, while C2000 digital signal processors can be used for complex systems with more functionality.

Motor:

E-bikes typically use either a brushed or brushless DC motor. Although brushless motors are more reliable and efficient, they add weight to the bike.

Battery:

Battery types have evolved from lead-acid to lithium-ion. Lead-acid batteries are widely used due to their low cost, but they are larger, heavier, and less environmentally friendly than lithium-ion batteries.

Power Management:

Provides the power required to run functional blocks and monitors battery activity. For low-end e-bikes, a host controller with comparators and discrete devices can be used to manage lead-acid batteries. More complex e-bikes use specific ICs that provide battery protection, monitoring, and fuel gauging to provide users with safety and important information about lithium-ion batteries.

EV HEV Level 1 and Level 2 charger block diagram (SBD) using TI digital power controllers, communication devices, high-performance drivers and interface devices.

Design Considerations

Plug-in Hybrid Electric Vehicles (PHEVs) and Battery Electric Vehicles (BEVs) are two rapidly emerging technologies that use powerful electric motors and high-voltage battery packs as a source of power and energy. Due to the limited capacity of the batteries, PHEVs and BEVs must be recharged periodically, which is usually done by connecting to the power grid in some form. For most users, Level 1 charging (120 VAC at 15A-20A) will be the most available power source, and since all users have easy access to the onboard charger, it should be able to handle all onboard chargers. In its current state, most users prefer to take advantage of the faster Level 2 charging (240 VAC at 40A). Level 2 charging takes less time to charge than Level 1 charging, but requires a larger power source to supply the corresponding current and voltage. By being able to take advantage of both charging options, you provide customers with greater flexibility in charging options, as well as more locations where charging can be provided.

Level 1 and 2 charging systems for these vehicles contain an AC/DC converter that generates a DC voltage from the AC line. These input supplies need to undergo power factor correction (PFC) to improve the power factor to meet regional regulatory standards. At the heart of the inverter is a real-time C2000 microprocessor. This controller is programmed to execute control loops to implement all required power management functions, including AC/DC with PFC and DC/DC to create the required battery charging profile. The C2000 controller contains advanced peripherals such as high-precision PWM outputs and ADCs that can read the ADC and adjust the PWM in a single clock cycle, enabling real-time control.

For safety reasons, it is also necessary to isolate the processor and the current and voltage, as well as the communication bus to the outside world. TI digital isolators have logic input and output buffers, which are separated by TI silicon dioxide (SiO2) isolation barriers that provide 4kV isolation. When used with isolated power supplies, these devices can block high voltages, isolate grounds, and prevent noise currents from entering the local ground and interfering with or damaging sensitive circuits. High-performance analog parts can also provide important system functions such as MOSFET drivers, sensor feedback, chip power supplies and communication transceivers.

Communications for Level 1 and Level 2 onboard charging systems are application specific. It depends on whether the consumer needs such a system to connect to the grid. Level 1 charging may be less common in the public sector and most widespread in the home charging sector. Level 2 charging, on the other hand, will benefit from the integration of power line communications (PLC) or wireless protocols to enable direct communication between the charging station and the utility company. Both charging levels offer users the option of connecting to smart meter type applications or logging data to their home area network (HAN) for personal use via PLC or wireless protocols. Other communication options provide users with greater flexibility to take advantage of the full benefits of plug-in vehicles.

EV HEV Level 3 charger block diagram (SBD) using TI digital power controllers, communication devices, high-performance drivers and interface devices.

Design Considerations

Plug-in Hybrid Electric Vehicles (PHEV) and Battery Electric Vehicles (BEV) are two rapidly emerging technologies that use powerful electric motors and high-voltage battery packs as a source of power. Due to the limited capacity of the battery, PHEVs and BEVs must be recharged periodically, which is usually done by connecting to the power grid. When this is done, some form of communication (PLC, wireless, or RFID) can be used to manage charging activities and help identify and authenticate the car or be used by the owner for billing purposes. Level 3 charging will play an important role in the public charging field to reduce charging time and enable users to benefit from mobile charging.

The Level 3 charging system for these cars consists of an AC/DC converter that generates a DC voltage from the AC line. These input sources need to undergo power factor correction (PFC) to improve the power factor to meet regional regulatory standards. At the heart of the inverter is a real-time C2000 microprocessor. This controller is programmed to execute the control loop to implement all required power management functions, including AC/DC with PFC and DC/DC to create the required battery charging profile. The C2000 controller includes advanced peripherals such as high-precision PWM outputs and ADCs that can read the ADC and adjust the PWM in a single clock cycle, enabling real-time control.

While the C2000 manages power, the host controller is responsible for driving the display and communicating directly with the onboard battery pack using information provided by the communications modem and temperature sensing. Necessary information for the charging profile is sent to the power controller, while important charging diagnostics and battery status are sent to the display of the 3-level charging system.

For safety reasons, it is also necessary to isolate the processor and the current and voltage, as well as the communication bus to the outside world. TI digital isolators have logic input and output buffers separated by TI's silicon dioxide (SiO2) isolation barrier, which can provide 4kV isolation. When used with isolated power supplies, these devices can block high voltages, isolate grounds, and prevent noise currents from entering the local ground and interfering with or damaging sensitive circuits. High-performance analog parts can also provide important system functions such as MOSFET drivers, sensor feedback, chip power supplies and communication transceivers.

Communications on a single system can be handled by a single processor. More sophisticated systems with complex displays and online billing/reporting (e.g., Level 3 charging) may also require a controller. Implementing a low-frequency narrowband PLC (LF NB PLC) solution will provide the best fit for bandwidth, power and cost requirements. Operating in the narrowband domain (up to 500kHz) ensures data integrity while minimizing system cost. To do this, the standard will leverage existing power line infrastructure and provide a cost-effective way to integrate intelligent monitoring and control into new automotive electronic systems. Data rates range from 1.2kbps to hundreds of kbps, depending on existing standards. TI's PLC software is available through the plcSUITE library, allowing developers to support multiple modulations and standards in a unique design. Developers can implement SFSK IEC61334, PRIME and G3 standards, use FlexOFDM for custom OFDM implementations, and can also be upgraded for future standards. For more information, visit our PLC applications page. Additionally, wireless communication and/or RFID may be required as a second communication protocol and a means of identification and billing.