Boost control apparatus based on output current change rate
A boost control apparatus is provided with: a controlling device configured (i) to perform first duty control by a first control parameter if output current that flows through a reactor is not near zero, and (ii) to perform second duty control by a second control parameter if the output current is near zero, during one-side element control for driving only one of a first switching element and a second switching element, each of which is connected to a reactor in series. A rate calculating device is provided that is configured to calculate a change rate of the output current to a change amount of a duty value in the first duty control and the second duty control. A control determining device is also provided that is configured to control the controlling device to perform the second duty control regardless of the output current, if the change rate is less than a predetermined value.
1. A boost control apparatus that can realize one-side element control for driving only one of a first switching element and a second switching element, each of which is connected to a reactor in series, said boost control apparatus comprising:
a controlling device configured (i) to perform first duty control by a first control parameter if output current that flows through a reactor is not near zero, and (ii) to perform a second duty control by a second control parameter if the output current is near zero;
a rate calculating device configured to calculate a change rate of the output current to a change amount of a duty value in the first duty control and the second duty control; and
a control determining device configured to control said controlling device to perform the second duty control regardless of the output current, if the change rate is less than a predetermined threshold such that even if the value of the output current is not near zero, the second duty control is performed during zero crossing if the calculated change rate of the output current is less than the predetermined threshold.
2. The boost control apparatus according to claim 1 , wherein said control determining device is to control said controlling device to perform the first duty control regardless of the output current, if the change rate is not less than the predetermined threshold.
3. The boost control apparatus according to claim 1 , wherein said controlling device is to perform control for increasing continuity of the first control parameter and the second control parameter when switching between the first duty control and the second duty control.
4. The boost control apparatus according to claim 3 , wherein the first duty control and the second duty control include proportional integral control, and said controlling device is to add a difference between the first control parameter and the second control parameter to an integral term in the proportional integral control, thereby increasing the continuity of the first control parameter and the second control parameter.
5. The boost control apparatus according to claim 1 , wherein the first duty control and the second duty control include feedback control, and said controlling device is to switch a gain of the feedback control when switching between the first duty control and the second duty control.
6. A boost control apparatus that can realize one-side element control for driving only one of a first switching element and a second switching element, each of which is connected to a reactor in series, said boost control apparatus comprising:
a controlling device configured (i) to perform first duty control by a first control parameter if output current that flows through a reactor is not near zero, and (ii) to perform a second duty control by a second control parameter if the output current is near zero;
a rate calculating device configured to calculate a change rate of the output current to a change amount of a duty value in the first duty control and the second duty control; and
a control determining device configured to control said controlling device to perform the second duty control regardless of the output current, if the change rate is less than a predetermined threshold such that even if the value of the output current is not near zero, the second duty control is performed during zero crossing.
7. The boost control apparatus according to claim 6 , wherein said control determining device is to control said controlling device to perform the first duty control regardless of the output current, if the change rate is not less than the predetermined threshold.
8. The boost control apparatus according to claim 6 , wherein said controlling device is to perform control for increasing continuity of the first control parameter and the second control parameter when switching between the first duty control and the second duty control.
9. The boost control apparatus according to claim 8 , wherein the first duty control and the second duty control include proportional integral control, and said controlling device is to add a difference between the first control parameter and the second control parameter to an integral term in the proportional integral control, thereby increasing the continuity of the first control parameter and the second control parameter.
10. The boost control apparatus according to claim 6 , wherein the first duty control and the second duty control include feedback control, and said controlling device is to switch a gain of the feedback control when switching between the first duty control and the second duty control.