Variable frequency drive overvoltage protection
First Claim
1. A method comprising:
- operating a variable frequency motor drive including an AC/DC converter electrically coupled with an AC power source, a DC link electrically coupled with the AC/DC converter, and a DC/AC converter electrically coupled with the DC link;
receiving information indicative of a voltage of the DC link at a microprocessor-based controller;
processing the received information to model a condition of at least one power electronics component of the variable frequency motor drive; and
disconnecting the AC/DC converter from the AC power source if the modeled condition meets a protection criterion;
wherein the disconnecting comprises performing a shunt trip operation performed in response to an evaluation of a DC bus voltage relative to a threshold, the shunt trip operation occurring without occurrence of an overcurrent condition.
1 Assignment
0 Petitions
Accused Products
Abstract
Overvoltage protection apparatuses, systems and methods for variable frequency motor drives are disclosed. In an exemplary embodiment, a variable frequency motor drive system including a rectifier, a DC bus electrically coupled with the rectifier, and an inverter electrically coupled with the DC bus is provided. A protection device electrically coupled with the rectifier and configured to interrupt power supply to the system based upon fault conditions is provided. A controller is provided and configured to receive information indicative of a voltage of the DC bus, process the received information to model a condition of at least one component of the variable frequency motor drive, and control the protection device to interrupt power supply to the variable frequency motor drive if the modeled condition meets a fault criterion.
33 Citations
22 Claims
-
1. A method comprising:
-
operating a variable frequency motor drive including an AC/DC converter electrically coupled with an AC power source, a DC link electrically coupled with the AC/DC converter, and a DC/AC converter electrically coupled with the DC link; receiving information indicative of a voltage of the DC link at a microprocessor-based controller; processing the received information to model a condition of at least one power electronics component of the variable frequency motor drive; and disconnecting the AC/DC converter from the AC power source if the modeled condition meets a protection criterion; wherein the disconnecting comprises performing a shunt trip operation performed in response to an evaluation of a DC bus voltage relative to a threshold, the shunt trip operation occurring without occurrence of an overcurrent condition. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A system comprising:
-
a variable frequency motor drive including a rectifier, a DC bus electrically coupled with the rectifier, and an inverter electrically coupled with the DC bus; a protection device electrically coupled with the rectifier and configured to interrupt power supply to the variable frequency motor drive based upon a received triggering signal; a controller configured to receive information indicative of a voltage of the DC bus, process the received information to model a condition of at least one component of the variable frequency motor drive, and provide a triggering signal to the protection device to interrupt power supply to the variable frequency motor drive if the modeled condition meets a fault criterion, the triggering signal being effective to interrupt power to the drive in response to an evaluation of a DC bus voltage relative to a limit and without regard to presence or absence of an overcurrent condition. - View Dependent Claims (12, 13, 14, 15, 16)
-
-
17. An apparatus comprising:
-
a non-transitory computer readable medium configured with instructions executable by a computer to; determine a model state of at least one component of a variable frequency drive system including an AC/DC converter, a protection device electrically coupled between the AC/DC converter and the AC power source, and a DC link electrically coupled with the AC/DC converter based upon sampled DC link voltage information; and control the protection device to perform a shunt trip in response to a DC bus voltage condition and irrespective of an overcurrent condition, the shunt trip operation being effective to disconnect the AC/DC converter from the AC power source and to disconnect the motor from the AC input based upon the determined model state. - View Dependent Claims (18, 19, 20, 21, 22)
-
Specification