Long Step-Out, High Frequency Drive System

High Frequency

Upwing’s VSDs are designed to drive high-speed machines and machines with low impedance. This is achieved by utilizing silicon carbide (SiC) MOSFET technology on the switching devices of the motor drive inverter. The technology, initially developed for space applications, enables switching at a frequency that is synchronized to the fundamental frequency of the machine. Consequently, the fundamental frequency of the machine can be high without incurring a large distortion in the current that is drawn by the machine.

In addition, Upwing’s high frequency drives include a simple inductance filter, which reduces the distortion of the current that is drawn by the machine. In fact, the filter limits the maximum distortion of the machine currents. In other words, the drive does not need to rely upon the machine inductance to limit the distortion in the currents that are drawn by the machine. The combination of high switching frequency that is synchronized to the fundamental frequency of the machine, dynamic deadtime insertion and a simple inductance filter make Upwing’s high frequency variable speed drives an ideal choice for low-impedance and high-speed machines.

Active and Passive Grid Rectifiers

Upwing’s VSD is designed with both active and passive grid rectifier options built in. Based on the grid condition, the rectifier option can be selected through the control settings. The ability to choose between these two options is a distinguishable feature of Upwing’s VSDs, which are not offered or incorporated by commercial VSD manufacturers. The advantage of an active rectifier is that it offers very low current distortion to the grid; also, it can operate at a wide input voltage range.

In remote areas, the grid is typically soft, and in most cases, is generated by simple single phase to three phase rotary converters. An active rectifier at the front end of the VSD provides low harmonics but in some cases can result in unstable input voltage. In such installations, a passive option can be enabled to prevent oscillations if the grid can tolerate higher harmonics.

High Reliability

Reliability and long operating life are at the forefront of importance in the design of Upwing’s power electronics drives. This is obtained by keeping the electrical and thermal stresses on the components within the drive to reasonable levels. The reliability of Upwing’s drives is further increased by reducing the parts count in the drive. In particular, the avoidance of requiring position feedback from the machine and voltage feedback for the machine greatly increases the robustness of the drive. All Upwing drives go through rigorous electrical and thermal testing before they leave our factory, minimizing manufacturing and component infant mortality issues. High reliability, reasonable stress levels and rigorous testing result in the long product life spans of our variable speed drives.

Customization

Upwing’s variable speed drives are re-programmable in order to meet the requirements of applications. This is achieved through the use of generic embedded software and unique parameter files that are customized for a particular application. Typical drive characteristics, such as current limits, overspeed limits and acceleration rates are readily changeable. For applications that require unique capabilities, the embedded software also can be modified. The ability to re-program the embedded controllers coupled with the ability to customize the drive hardware allows our drives to meet the needs of different applications.

Autonomous Control

The data interface and communication channels of Upwing’s VSDs also enable autonomous control of our downhole rotating devices. The VSD control has ground fault protection. In the event of a ground fault, the control will shut down. External protective relays, such as Beckwith or Basler protective relays, can also be used.