In the current closed loop control

In the current closed loop control, accurate phase current information often by current transformer, hall effect sensor or magnetic resistance sensor, such as the provision of, but these element was bulky and expensive, and is not suitable for automatic assembly. At low power motor control can use simple shunt resistance, and measuring the resistance at the ends of the pressure drop, but this also need complex and precision of the signal processing circuit will typical voltage range is only (200 mv small pressure drop into digital controller can be used in the form of this circuit is the most difficult part is to rotary joints as high as 600 v to 1200 v common mode offset and the phase output node place high dv/dt cause switch noise environment tolerance ability.

An ingenious solution is to rotary union use HVIC technology integration difference measurement circuit and analog to digital converter, has the common mode noise and dv/dt noise suppression Ji Φ mother eye socket groove cabled order  frequency Bian Finn about ammonia Wen Zheng faded  catch 刂 broken Mao benzene of flood wall male lotus root fat yu groove Bian return take H bean? An example is shown in IR2175 phase current sensor chip. IR2175 input for a (260 mv linear range of differential voltage, and the common mode offset voltage can be as high as 600 v, dv/dt can be as high as 50 v/ns. IR2175 output for low voltage side PWM signal, the carrier frequency for 130 KHZ, duty ratio and differential voltage level in proportion.
When the input beyond linear scope limitation, can pass an additional pin output flow signal, over current signal delay only 2 milliseconds, thus provides a relatively quick shutoff channel to protect IGBT prevent short circuit conditions. 3: high pressure integrated chip technology make the space saving of the current sensor chip IR2175 IR2175 can and digital control chip direct docking, through the digital control chip direct calculation make IR2175 PWM output into 10 resolution digital quantity. Integrated design platform Comprehensive MCE in digital control, HVIC in analog circuit and the power module IPM's various advantages can with lower cost to realize higher performance of new motor control integrated design platform. Due to the increase in the integration, and components number can be reduced, and help to fiber optic rotary joint simplify the manufacturing process, especially can simplify the power device assembly and heat dissipation problem and so on. Development support including ServoDesigner configuration tools and in a single circuit board on the set all chipset assessment system, and therefore can be by reducing software development task quantity, and play MCE control engine deterministic advantage, and a unified design and test digital, analog and power chip mutual compatibility, advantages, build give a kind of low risk design environment.
More importantly, with special hardware resources to execute operation intensive algorithm can make the solution for extra performance. If again with the aid of an external MCU application layer to execute tasks, the integrated design platform is enough to support a complete set of system control implementation scheme.