With the gradual improvement of the consumption level of domestic consumers, dishwashers are rapidly entering the era of popularization. Based on Microchip's dsPIC33 series MCUs, Beyond International develops a dishwasher water pump solution, which effectively realizes the sensorless sinusoidal control of the brushless motor. This solution has the advantages of low cost, small size, and easy adaptation to various brushless motors. The scheme design has a fast startup speed, a built-in startup failure detection mechanism, and a high startup reliability.

The dishwasher has a built-in water spray pump, usually composed of a brush motor, an induction motor or a brushless motor. Due to the characteristics of long life, quiet, high efficiency and low electromagnetic radiation, brushless motors will gradually replace other motors and become the preferred motor for dishwasher pumps in the future.

Functional block diagram 

Features 

•   Output power: 50W ~ 100W

•   Control mode: FOC sine control

•   Starting method: no sensor

•   Control algorithm: SMO (refer to Microchip AN1078)

•   Modulation method: SVPWM

•   Current sampling method: dual resistance sampling

•   Modulation frequency: 20KHz

•   Motor speed: 3200RPM @ 3 pole pair

•   Water spray volume: 30L / MIN

•   Protection function: blocking, over-current, under-voltage, over-voltage, over-temperature protection, etc.

•   Industrial grade devices ( -40 ~ 85 degrees Celsius)

•   Main features: fast and reliable start-up, high efficiency and low noise

Application field 

• Dishwasher pump