A power optimizer is a component-level DC/DC converter for PV DC input/output. One or two PV modules are connected to a power optimizer with maximum power point tracking (MPPT) function. The power optimizer is generally installed on the backplate of the module, which can connect the PV current in series and into the combiner box or PV inverter according to the need of the modules in series to realize the module-level control. The widespread use of power optimizers can make full use of rooftop resources, recover power generation losses, and generally increase the power output by 5% to 25%. It realizes rapid shutdown at the component level to ensure safe operation, and also monitors and maintains PV modules to timely detect and prevent abnormal problems. 

Based on the APM32F407 series MCU, the power optimizer solution obtains the voltage and current of PV input/output through the ADC module. The PV input voltage and current are mainly used to implement the MPPT algorithm, control system loops, and auxiliary software protection. After the MPPT algorithm obtains the voltage of the maximum power point, the real-time tracking of the voltage of the maximum power point is realized through the output duty cycle controlled by the loop. The MCU's advanced timer module can output PWM waveforms with specific duty cycle control of the circuit as required to realize the function of a power optimizer. At the same time, it interacts with the outside world and receives scheduling through its communication interface.

APM32F407 Power Optimizer Solution Advantages

•  32-bit Arm® Cortex®-M4 core, with a maximum frequency of 168MHz, supporting MPPT algorithm and DC/DC loop control.

•  Built-in three 12-bit high-precision ADCs, each with up to 21 external channels, supporting DMA to meet the needs of the power optimizer's 2-channel voltage and current acquisition.

•  Two 16-bit advanced timers TMR1 and TMR8 that can provide 7-channel PWM output, supporting functions such as dead zone generation and brake input and meeting the control requirements of the 4 switching devices of the power optimizer. The brake input can quickly stop the device in case of an emergency to prevent damage.

•  Four USART communication interfaces to meet the interaction requirements of the battery and the upper system.

•  Flash capacity up to 1MB and SRAM capacity up to 192KB to meet program storage and computing requirements, with redundancy for program expansion.

•  The 4KB backup register can flexibly save control parameters without external EEPROM.

Geehy APM32 series industrial-grade MCU has shown great flexibility and application innovation in terms of performance, power consumption, peripherals, and packaging. The APM32F407 industrial-grade high-performance MCU not only has the high computing and high security required for complex applications in new energy but also offers a variety of ways to simplify the complex design.