Power converters in which the input power coupling times are adjusted in conjunction with cycle skip counts
AssigneeFyresStorm, Inc.
InventorsMilton D. Ribeiro, Kent Kernahan
Life of this patent
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Abstract
In a power converter, an input power source (98) is intermittently coupled to provide a current flow (Icoil) in consecutive cycles (T) to generate an output voltage (Vo). The coupling durations (Tp) are adjusted in conjunction with a cycle skip count (112CNT) which is the count of cycles in which no coupling occurs. In some embodiments, the adjustments are performed to keep the coupling durations near the maximum efficiency range (between TLOW and THIGH), and the skip count is adjusted at the same time to obtain the desired output voltage in the presence of load current variations. The coupling frequencies are kept in a desired range to avoid interference with other circuit elements.
Claims60
A method for regulating an output voltage of a power converter, the method comprising intermittently coupling an input power source to provide a current flow to generate the output voltage, wherein in consecutive time cycles T1, T2, . . . Tn, . . . the input power source is coupled for respective time durations Tp≧0 where Tp=Tp(T1), Tp(T2), . . . Tp(Tn), . . . in respective cycles T1, T2, . . . Tn, . . . , the method further comprising determining the durations Tp, wherein determining Tp comprises:
- (1) obtaining a cycle skip count representing a number of cycles with Tp=0 between cycles with Tp>0;
- (2) for at least one cycle Ti for which Tp(Ti)>0, determining whether or not a condition 1 holds true, wherein the condition 1 is either (i) a condition that Tp(Ti) is below a predetermined value TLOW, or (ii) a condition that Tp(Ti) is less than or equal to TLOW, or (iii) a condition that a predefined increasing function of Tp(Ti) is below TLOW, or (iv) a condition that said increasing function of Tp(Ti) is less than or equal to TLOW;
- (3) if the condition 1 holds true, then:
- (3A) increasing Tp(Ti);
- and
- (3B) increasing the skip count.
A method for regulating an output voltage of a power converter, the method comprising intermittently coupling an input power source to provide a current flow to generate the output voltage, wherein in consecutive time cycles T1, T2, . . . Tn, . . . the input power source is coupled for respective time durations Tp≧0 where Tp=Tp(T1), Tp(T2), . . . Tp(Tn), . . . in respective cycles T1, T2, . . . Tn, . . . , the method further comprising determining the durations Tp, wherein determining Tp comprises:
- (1) obtaining a cycle skip count representing a number of cycles with Tp=0 between cycles with Tp>0;
- (2) determining whether or not a condition 1 holds true, wherein the condition 1 is either (i) a condition that Tp(Ti) is above a predetermined value THIGH, or (ii) a condition that Tp(Ti) is above or equal to THIGH, or (iii) a condition that a predefined increasing function of Tp(Ti) is above THIGH, or (iv) a condition that said increasing function of Tp(Ti) is greater than or equal to THIGH;
- (3) if the condition 1 holds true, then:
- (3A) decreasing Tp(Ti);
- and
- (3B) decreasing the skip count.
Dependencies are inferred from the claim text.