WPG Group launches 250W micro-inverter solution based on Microchip products

On June 20, 2023, WPG Holdings, a leading international semiconductor component distributor dedicated to the Asia-Pacific market, announced that its subsidiary Pinjia has launched a 250W micro inverter solution based on Microchip's dsPIC33CK256MP505 chip.

Figure 1- A display board of the 250W micro inverter solution of WPG based on Microchip products

With the unstable supply of traditional fossil energy and the introduction of carbon neutrality standards, the demand for renewable energy such as solar energy and wind energy has increased sharply. In the current application of renewable energy, PV (photovoltaic power generation) systems have significant advantages. They can be used as independent power generation systems or connected to existing power grids, and have high flexibility and adaptability. In PV systems, inverters are core equipment, which directly affects the safety and stability of power transmission. Among all inverter types, micro inverters are popular due to their high energy utilization and easy maintenance, and have broad market prospects. In this context, GLP Power has launched a 250W micro inverter solution based on the Microchip dsPIC33CK256MP505 chip, which can accelerate the construction of solar power generation.

Figure 2-Application scenario of 250W micro inverter solution of GPON based on Microchip products

The core of this solution uses Microchip's dsPIC33CK256MP505 digital signal controller, which is equipped with a 100MHz dsPIC DSC® core and integrates DSP and enhanced on-chip peripherals. It has an internal flash program memory that is readable, writable and erasable during normal operation (over the entire VDD range). In addition, the product has an on-chip phase-locked loop (PLL) that can increase the operating frequency of the selected internal/external oscillator source.

Figure 3 - Block diagram of the 250W micro-inverter solution from WPG based on Microchip products

In addition to the high-speed computing MCU, this solution also uses industrial-grade components such as Microchip's MCP14E4-E/SN, MCP16301T-I/CHY, MCP1700T-3302E/MB, MCP9700-E/LT, MCP6022T-I/SN, Infineon's IPB60R190C6, IRFS4321TRLPBF and National's LM5008 AMM/NOPB. The circuit composed of these excellent products can reduce the cost of PV system design, while achieving a more refined maximum power point tracking function, further improving the overall power generation efficiency of the system.

Core technology advantages:

dsPIC33CK256MP505 Advantages:

 High-speed DSP operation: The main controller Microchip dsPIC33CK256MP505 is a high-performance digital power supply dedicated controller, the DSC operating frequency is 100MHz, and it runs in a single instruction cycle;

High resolution PWM.

Circuit design advantages:

Interleaving flyback converters can reduce the RMS ripple current through the bulk input electrolytic capacitors, thereby extending the life of the capacitors;

Interleaved operation can also reduce the output current ripple, thereby reducing the THD of the output current;

Measure the grid voltage, which is required for phase-locked loop (PLL), output current control and system islanding operation. To synchronize the inverter output voltage with the grid voltage and detect the system islanding effect, the inverter output voltage must be measured first;

Measure the grid current to ensure that the sinusoidal current provided by the inverter is in phase with the grid.

Program Specifications:

 Input power: 250W (Max);

Output power: 215W (Max);

Open circuit PV voltage: 53Vdc;

Maximum power point tracking: 99.5%;

MPPT voltage: 25~45Vdc;

 AC output voltage range: 210Vac~264Vac (230Vac), 90Vac~140Vac (120Vac);

Output TDD: <5%;

Output power factor: 0.95;

Peak efficiency: 94.5% (230Vac unit-nominal Condition).