Anti-rebounding control apparatus and method in an electrical swing system of a hybrid excavator

Patent metadata

Field	Value
Publication number	US-9024565-B2
Application number	US-201114002039-A
Country	US
Kind code	B2
Filing date	Mar 23, 2011
Priority date	Mar 23, 2011
Publication date	May 5, 2015
Grant date	May 5, 2015

Abstract

An anti-rebounding control apparatus is provided, which includes an anti-rebounding controller outputting a first command for setting a torque limit value to “0” if an electric motor speed value is equal to or smaller than an upper threshold value and equal to or larger than a lower threshold value in the case where a speed command value of “0” is input and outputting a second command for setting the torque limit value to a maximum value if the electric motor speed value is smaller than the lower threshold value, a torque regulator setting the torque limit value to “0” when the first command is input and setting the torque limit value to the maximum value when the second command is input, and an electric motor inverter intercepting a power that is supplied to an electric motor if the torque limit value is set to “0” and re-supplying the power to the electric motor if the torque limit value is set to the maximum value. Accordingly, the same performance as an anti-rebounding system that is used in a swing system of an existing hydraulic excavator can be implemented even in a system that performs a swing operation using an electric motor such as a hybrid (or electric) excavator.

First claim

The invention claimed is:

1. An anti-rebounding control method in an electric swing system of a hybrid excavator, comprising:
comparing an electric motor speed feedback value that is a speed value fed back from an electric motor with a preset upper threshold speed value and a preset lower threshold speed value if an input speed command value is “0” (if an operator intends to stop a swing operation of an upper swing structure);
setting a torque limit value to “0” if the electric motor speed feedback value is equal to or smaller than the upper threshold speed value and equal to or larger than the lower threshold speed value as the result of comparison, and setting a torque limit value to a maximum value so that a power is re-supplied to the electric motor if the electric motor speed feedback value is smaller than the lower threshold speed value (just before the electric motor stops); and
intercepting the power that is supplied to the electric motor if the torque limit value is set to “0” and re-supplying the power to the electric motor if the torque limit value is set to the maximum value.

2. The anti-rebounding control method according to claim 1 , wherein the step of setting the torque limit value to “0” or the maximum value sets a predetermined rate limit (slope) and changes and sets the torque limit value to “0” or the maximum value in proportion to the set rate limit (slope), and
the step of intercepting or supplying the power to the electric motor according to the set torque limit value intercepts or supplies the power in proportion to the set rate limit (slope).

3. An anti-rebounding control apparatus in an electric swing system of a hybrid excavator, comprising:
an anti-rebounding controller outputting a first command for setting a torque limit value to “0” if an electric motor speed feedback value that is a speed value fed back from an electric motor is equal to or smaller than an upper threshold speed value and equal to or larger than a lower threshold speed value in the case where an input speed command value is “0” (in the case where an operator intends to stop a swing operation of an upper swing structure), and outputting a second command for setting the torque limit value to a maximum value so that a power is re-supplied to the electric motor if the electric motor speed feedback value is smaller than the lower threshold speed value (just before the electric motor stops);
a torque regulator setting the torque limit value to “0” when the first command is input and setting the torque limit value to the maximum value so that the power is re-supplied to the electric motor when the second command is input; and
an electric motor inverter intercepting the power that is supplied to the electric motor if the torque limit value is set to “0” and re-supplying the power to the electric motor if the torque limit value is set to the maximum value.

4. The anti-rebounding control apparatus according to claim 3 , wherein the anti-rebounding controller comprises:
a speed value comparison unit comparing the electric motor speed feedback value that is the speed value fed back from the electric motor with the preset upper threshold speed value and the preset lower threshold speed value if the input speed command value is “0” (if the operator intends to stop the swing operation of the upper swing structure); and
a command output unit outputting the first command for setting the torque limit value to “0” if the electric motor speed feedback value is equal to or smaller than the upper threshold speed value and equal to or larger than the lower threshold speed value as the result of comparison and outputting the second command for setting the torque limit value to the maximum value so that the power is re-supplied to the electric motor if the electric motor speed feedback value is smaller than the lower threshold speed value (just before the electric motor stops).

5. The anti-rebounding control apparatus according to claim 3 , wherein the torque regulator changes and sets the torque limit value to “0” or the maximum value in proportion to a set rate limit (slope), and
the electric motor inverter intercepts or supplies the power in proportion to the set rate limit (slope).

Assignees

• Kim Ji-Yun
• Volvo Constr Equip Ab

Inventors

• Kim Ji-Yun

Classifications

• H02P3/02 Primary

  Details {of stopping control} · CPC title

• B60W20/00 Primary

  Control systems specially adapted for hybrid vehicles {(hybrid vehicle design, B60K6/00; electric vehicles B60L)} · CPC title

• E02F9/123

  Drives or control devices specially adapted therefor (E02F9/125 and E02F9/128 take precedence) · CPC title

• B60Y2200/412

  Excavators · CPC title

• E02F9/2095

  Control of electric, electro-mechanical or mechanical equipment not otherwise provided for, e.g. ventilators, electro-driven fans (control of hydraulic driven equipment E02F9/22) · CPC title