Hamilton Sundstrand Corporation

Sridhar Katakam

Nageswara Rao Kalluri

Pravinsharma Kaliyannan Eswaran

Surendra Somasekhar Valleru

Rajkumar Perumal

Somasekhar Valleru

David Frederick Brookes

Rodrigo Fernandez-Mattos

Ashish Vijay

Sesh Mohan Rao

Priya Kakarla Naga Lakshmi

Shobha Ramanjani

Shobhit Agrawal

A circuit calibration system can include a calibration voltage source, a calibration output line, and a variable voltage system connected between the calibration voltage source and the calibration output line. The variable voltage system can be configured to provide a variable calibration voltage to the calibration output line.

Circuit calibration systems

A switch control system includes a first voltage source configured to output a first source voltage on a first voltage line. The system includes a first gate driver, a second gate driver, a third gate driver, and a fourth gate driver. Each of the gate drivers includes shoot through protection (STP) configured to prevent a first switch and a second switch of the system from ever both being closed at once thereby preventing shoot voltages from a DC bus to ground through the first and second switches.

Shoot through protection in motor drives with single supply gate drives

A switch control system can include a voltage source configured to output a source voltage on a voltage line, and a first gate driver connected to a gate control signal line to receive a gate control signal from a controller. The first gate driver can be connected to the voltage line to receive the source voltage, and the first gate driver can be connected to a first terminal line to output a first gate voltage signal to a first terminal of a switch. The system can include an inverter connected to the gate control signal line configured to receive the gate control signal and output an inverted gate control signal. The system can include a second gate driver connected to the inverter to receive the inverted gate control signal from the inverter. The second gate driver can be connected to the voltage line to receive the source voltage, and the second gate driver can be connected to a second terminal line to output a second gate voltage signal to a second terminal of a switch.

Bipolar gate drive systems

A resistance temperature detector includes a single channel analog to digital converter (ADC) comprising a first channel input and a reference voltage input. The detector also includes a resistance temperature detector (RTD) element connected to the first channel input and a current sense element in series with the RTD element. The current sense element is connected to the reference voltage input. The detector also includes a power source connected to the RTD element and a controller configured to: receive an output of the single channel ADC to determine a temperature at the RTD element. The output of the single channel ADC comprises a bit representation of a ratio between a first voltage across the RTD element and a reference voltage across the current sense element.

High accuracy computational method in resistance temperature detector measurements

A motor speed monitoring system can include a monitor channel having an input configured to connect to an inverter output of an inverter to receive motor command signals from the inverter, and an intelligence module configured to determine a motor speed based on the motor power signals from the inverter.

Motor speed measurement systems

A motor drive system includes a direct current (DC) bus that provides a DC link voltage across a DC link capacitor, and a split DC link mid-point circuit connected in parallel with the DC link capacitor. The split DC link mid-point circuit establishes a mid-point reference based on the DC link voltage. A power inverter is in signal communication with the DC bus. The power inverter includes one or more gate driver units configured to drive one or more corresponding switches. Each gate driver unit includes a mid-point ground connection that is connected to the mid-point reference. The split DC link mid-point circuit can define a voltage divide that establishes the mid-point reference and can be used to monitor the DC link voltage.

Gate drive grounding scheme in motor drive systems for wide input DC link voltage

A holdup energy arrangement can include a motor control module configured to connect to motor power electronics to operate an inverter to control a motor. The motor control module can operate at a lower voltage than the motor power electronics. The arrangement can include a power supply operatively connected to the motor control module and configured to provide power the motor control module and a converter operatively connected to the power supply and configured to be electrically connected to a DC link capacitor of the motor power electronics. The arrangement can also include a logic control module configured to control the converter to selectively allow energy to flow from the DC link capacitor, through the converter, and to the power supply to provide holdup energy to the power supply with energy from the DC link capacitor.

Holdup energy arrangements

A system and method for testing a resolver circuit is provided. Aspects include a resolver circuit including an excitation signal output, a sine signal input, and a cosine signal input, a switching matrix comprising an excitation input connected to the excitation signal output, a first output connected to the sine signal input, and a second output connected to the cosine signal input, wherein the switching matrix further includes a set of switches configured to route an excitation signal from the resolver circuit to mimic a sine and cosine signal output corresponding to a specified angle for a resolver sensor, a controller configured to operate the resolver circuit to output an excitation signal, determine an angle value based on a sine signal received and a cosine signal received from the switching matrix, and compare the angle value to the specified angle to determine a fault condition in the resolver circuit.

Standalone resolver angle verification

A voltage measurement system and method is provided. Aspects include a comparator having a positive and a negative input terminal, a processor configured to supply a reference voltage signal to the negative input terminal, wherein the positive input terminal receives an input voltage, setting the reference voltage signal to a zero voltage signal, determine a line frequency of the input voltage based on a timing signal from the comparator and determining a first pulse width of the input signal based on the timing signal, set the reference voltage to a PWM signal with a fixed duty cycle, receive the timing signal from the output of the comparator, determine a rising edge and a falling edge associated with the input voltage based on the timing signal, and determine a peak value of the input voltage based on a second pulse width between the rising and falling edge.

Alternative voltage measurement over extended operating conditions

An intelligent architecture system is provided. The intelligent architecture system includes an input line, an output line and an intelligent architecture operably interposed between the input line and the output line. The intelligent architecture is configured to control a voltage of the output line in accordance with a voltage of the input line.

Intelligent architecture for actuator motor drive powered from wide-input high-voltage direct current

System and methods for accuracy improvement of an LVDT are provided. Aspects include determining a first voltage from the first PGA and a second voltage from the second PGA, wherein the first voltage is determined from a PGA coupled to a first secondary winding, and wherein the second voltage is determined from a second PGA coupled to a second secondary winding, iteratively performing: analyzing the first voltage to determine a gain correction is needed for a first gain for the first PGA, the gain correction comprising change to the first gain, and analyzing the second voltage to determine a gain correction is needed for a second gain for the second PGA, the gain correction comprising change to the second gain, based on determining a gain correction is not needed for the first gain and the second gain, calculating a position based on the first voltage and the second voltage.

Accuracy improvement in linear variable differential transformer based position measurements

A threshold detection system can be configured to monitor a location (e.g., a DC link) for overcurrent. The threshold detection system can be configured to generate a pulse width modulated signal with a duty cycle that is proportional to current through the DC link. The threshold detection system can be configured to determine whether the duty cycle exceeds a selected threshold.

Threshold detection systems

Aspects include a hold-up capacitor charging circuit for a power supply. The hold-up capacitor charging circuit includes a voltage boosting charge pump circuit with a hold-up capacitor electrically coupled to a voltage source. The hold-up capacitor charging circuit also includes a fly-back circuit. The fly-back circuit includes a transformer with a primary winding electrically coupled to the voltage source and a secondary winding electrically coupled to a load. A switch is electrically coupled to the primary winding and the voltage boosting charge pump circuit. A controller is operable to open and close the switch to control energy transfer from the primary winding to the secondary winding and charge the hold-up capacitor responsive to voltages of the voltage source, the voltage boosting charge pump circuit, and a reflected voltage of the secondary winding at the primary winding.

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Bengaluru, India

Sridhar Katakam