Texas Instruments Corporation

Toshiba International Corporation

Raptor Lift Solutions, LLC

Mohammed Arefeen

Mark Douglas Rayner

Jim Childers

Wajiha Shireen

An electrical ride-through (ERT) unit is configured to apply a voltage to a drive circuit during disruptions of line voltage to the drive circuit. The ERT unit includes a capacitor on an ERT circuit that is prevented from applying the voltage to the drive circuit during normal operation of the drive circuit, and applies the voltage to the drive circuit during a voltage drop on the drive circuit.

Method and apparatus for riding through power disruptions of a drive circuit

Apparatuses and methods are described for implementing adjustable speed drives. For instance, an apparatus may comprise an inverter circuit configured to drive a multi-phase electrical load, the inverter configured to be powered by first and second direct-current (DC) bus lines, a fan drive circuit configured to be powered by the first and second DC bus lines, a fan configured to be controlled by the fan drive circuit and having a plurality of windings coupled together at an electrical node, a first capacitor having a first terminal coupled to the first DC bus line and a second terminal coupled to the electrical node, and a second capacitor having a first terminal coupled to the second DC bus lines and a second terminal coupled to the electrical node.

Use of cooling fan in adjustable speed drives

A portable diagnostic module may use a standardized physical interface to connect to a series of sensors. The module can be configured to accept different types of sensor outputs, and to collect the sensed data for use in local or networked analysis to help identify errors and faults before they occur.

Microcontroller-based diagnostic module

This invention detects a stall in a stepper motor by determining a motor winding current for each stepper pulse and determining if the winding current of a particular stepper pulse meets predetermined criteria. The motor winding current may be determined by measuring a voltage across an ON field effect transistor during a stepper pulse and calculating a winding current using an assumed ON field effect transistor resistance. The predetermined criteria may by a calculated motor winding current greater than a predetermined threshold, greater than prior pulse by more than a predetermined threshold or greater than a prior pulse by more than a predetermined factor.

Method of stall detection for stepper motor system

A modified PWM space vector technique is described which includes a DC ripple voltage measurement scheme supplying feed-back to a DSP controller which then computes and generates the instantaneous PWM drives required for ripple voltage cancellation in a lightly filtered line voltage node, and executes the interface to the multi-phase power inverter circuitry. This preferably becomes a part of a closed loop motor speed control process. Use of the modified PWM drive in this manner greatly reduces the value of the filter capacitor required, allowing for the use of non-electrolytic capacitors having greater reliability and being available at lower cost.

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Houston, TX, United States of America

Mohammed Arefeen