Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
230 words
An electric motor control apparatus in which a load current modulated in a pulse form and flowing in an electric motor is detected, and said load current is controlled by varying a pulse width of said load current so that an average value of said load current follows a command value, said electric motor control apparatus comprising: switching means for modulating a direct current supplied to said electric motor from a DC power supply in said pulse form; a current detector for detecting said load current flowing in said electric motor; an average load current detecting means for detecting the average value of said load current by inputting from said current detector the load current at a time point after said switching means is rendered conductive and after the lapse of a predetermined time which varies in accordance an "on" time of said switching means, and by assuming said inputted load current as the average value of said load current to be detected; an "on" time calculating means for determining the "on" time of said switching means in the next period based on the average value of said load current detected by said average load current detecting section and the command value; and a switching control means for on-off controlling said switching means in accordance with a commanded period and the "on" time calculated by said "on" time calculating means.
Claim 2
Dependent Claim
230 words
An electric motor control apparatus in which a load current modulated in a pulse form and flowing in an electric motor is detected, and said load current is controlled by varying a pulse width of said load current so that an average value of said load current follows a command value, said electric motor control apparatus comprising: switching means for modulating a direct current supplied to said electric motor from a DC power supply in said pulse form; a current detector for detecting said load current flowing in said electric motor; an average load current detecting means for detecting the average value of said load current by inputting from said current detector the load current at a time point after said switching means is rendered conductive and after the lapse of a predetermined time which varies in accordance an "on" time of said switching means, and by assuming said inputted load current as the average value of said load current to be detected; an "on" time calculating means for determining the "on" time of said switching means in the next period based on the average value of said load current detected by said average load current detecting section and the command value; and a switching control means for on-off controlling said switching means in accordance with a commanded period and the "on" time calculated by said "on" time calculating means.
Claim 3
Dependent Claim
17 words
An apparatus according to claim 1 wherein said switching means is a chopper circuit including a thyristor.
Claim 4
Dependent Claim
14 words
An apparatus according to claim 1 wherein said current detector includes an A/D converter.
Claim 5
Dependent Claim
16 words
An apparatus according to claim 1 wherein said switching control means is a pulse generating circuit.
Claim 6
Dependent Claim
36 words
An apparatus according to claim 1 further comprising a timer for generating an interrupt signal at each control period, and a further timer for generating an interrupt signal for read timing of said average load current.
Claim 7
Dependent Claim
12 words
An apparatus according to claim 5 wherein said both timers are programmable.
Claim 8
Dependent Claim
40 words
An apparatus according to claim 5 wherein said both timers are formed into a single timer for generating the interrupt signal at each control period and for generating the interrupt signal for the read timing of the average load current.
Claim 9
Dependent Claim
34 words
An apparatus according to claim 1, wherein said average load current detecting means, said "on" time calculating means, said switching control means, said A/D converter, and said timers are formed in an one-chip microcomputer.
Claim 10
Dependent Claim
34 words
An apparatus according to claim 3, wherein said average load current detecting means, said "on" time calculating means, said switching control means, said A/D converter, and said timers are formed in an one-chip microcomputer.
Claim 11
Dependent Claim
34 words
An apparatus according to claim 5, wherein said average load current detecting means, said "on" time calculating means, said switching control means, said A/D converter, and said timers are formed in an one-chip microcomputer.