Marco Giandalia

An integrated fault detector in high voltage technology for motor drive applications

In this paper, an integrated solution of fault detector for motor drive applications is presented. The circuit is developed in monolithic high voltage technology. The goal of the IC is the detection of different types of fault which can affect the three phase inverter or the motor in electrical drive systems. The fault condition is detected sensing a shunt resistor put on the DC+ bus of the inverter and can be communicated to the DSP using an open drain output pin of the chip. The proposed IC represents a versatile and inexpensive solution, requires few external passive elements and can be used in applications with the inverter DC+ bus up to 600 V. The circuit does not need any external supply. It offers the possibility to regulate the voltage threshold for the fault detection using two external resistors and guarantees the response time required by the considered applications. The designed circuit, its characteristics and its performances are reported and discussed.

Fast-responding over current detector circuit in high voltage technology for motor drive applications

A monolithic over current detector for motor drive application in high voltage technology is here presented. The goal of the IC is the detection of different types of faults which can affect a triphase inverter used in motor drives applications. The over current condition is detected sensing a shunt resistor put on the DC+ bus of the inverter and is communicated to the DSP using an open drain output pin. The proposed IC represents an integrated and inexpensive solution, has a very simple structure and can be used in application with the inverter DC+ bus up to 600 V. The circuit is self-supplied and exploits the possibility to easily regulate the voltage threshold for the over current detection. The designed circuit and the most significant simulations are reported. The circuit has been diffused in a test chip: measurements demonstrates the validity of the proposed solution.