Control of variable geometry turbochargers
Systems, methods, and computer-program products can pertain to a variable geometry turbocharger (VGT) control and can comprise: determining using a processor, whether a coast flag is set indicating that a work machine is coasting; holding the VGT at a current vane configuration as long as the coast flag is set; and returning the VGT to normal operation thereof upon a determination that the coast flag is reset.
1 . A work machine comprising:
an internal combustion engine;
a variable geometry turbocharger (VGT) having displaceable vanes; and
control circuitry constructed to:
determine the work machine is coasting without use of look-ahead data,
assert a coasting flag upon a determination that a gear threshold, a throttle threshold, a grade threshold, and a speed threshold have been met, and
output control signaling to maintain a current VGT vane configuration as long as the coasting flag is asserted.
2 . The work machine of claim 1 , wherein the determination that the work machine is coasting is achieved by a null position of an accelerator control.
3 . The work machine of claim 1 , wherein the coasting flag is held as long as the gear threshold, the throttle threshold and the grade threshold are met.
4 . The work machine of claim 1 , wherein the current vane configuration is held through a debounce period subsequent to the coasting enable flag being reset.
5 . The work machine of claim 4 , wherein the current vane configuration is ramped at a reset rate to meet a new vane configuration dictated by normal VGT operation.
6 . An internal combustion engine of a work machine comprising:
a variable geometry turbocharger (VGT) constructed to modulate intake air density of the internal combustion engine;
electronic machine control circuitry constructed to assert a coasting flag upon a determination that the work machine is coasting; and
VGT control circuitry constructed to maintain a current VGT vane configuration while the coasting flag is asserted and through a debounce period subsequent to the coasting flag being reset.
7 . The internal combustion engine of claim 6 , wherein the determination that the work machine is coasting is achieved by a null position of an accelerator control.
8 . The internal combustion engine of claim 6 , wherein the current vane configuration is ramped at a reset rate to meet a new vane configuration dictated by normal VGT operation.
9 . The internal combustion engine of claim 6 , wherein the determination that the work machine is coasting is achieved without use of look-ahead data.
10 . An internal combustion engine of a work machine comprising:
a variable geometry turbocharger (VGT) constructed to modulate intake air density of the internal combustion engine;
electronic machine control circuitry constructed to assert a coasting flag upon a determination that the work machine is coasting,
the coasting flag being asserted upon a determination that a gear threshold, a throttle threshold, a grade threshold, and a speed threshold have been met; and
VGT control circuitry constructed to maintain a current VGT vane configuration as long as the coasting flag is asserted.
11 . The internal combustion engine of claim 10 , wherein the coasting enable flag is held as long as the gear threshold, the throttle threshold and the grade threshold are met.
12 . A method of variable geometry turbocharger (VGT) control comprising:
determining, in real time, using a processor, whether a coast flag is set indicating that a work machine is coasting;
holding the VGT at a current vane configuration as long as the coast flag is set; and
returning the VGT to normal operation thereof upon a determination that the coast flag is reset, wherein returning the VGT to normal operation includes:
holding the current vane configuration through a debounce period; and
returning the VGT to normal operation subsequent to the debounce period.
13 . The method of claim 12 , further comprising ramping the current vane configuration to a new vane configuration per the normal operation of the VGT subsequent to the debounce period.
14 . The method of claim 12 further comprising setting the coasting flag upon a determination that a gear threshold, a throttle threshold, a grade threshold, and a speed threshold have been met.
15 . The method of claim 14 , wherein the coasting flag is held as long as the gear threshold, the throttle threshold and the grade threshold are met.
16 . The method of claim 12 , further comprising, before the holding the VGT at the current vane configuration as long as the coasting flag is set, configuring the VGT according to the current vane configuration from a previous vane configuration.
17 . The method of claim 12 , wherein the determination that the work machine is coasting is achieved without use of look-ahead data.