Abstract A multiplex control system including a plurality of controllers, the main controller being arranged by hardware, while the subsidiary controller being accomplished by software. Each of the controllers has a PID operator for calculating the proportional, differential and integral components of process data, and the difference of the integral components of both PID operators is processed through a first-order time lag operator and the result is used to correct the error of the output from the PID operator of the subsidiary controller. In the occurrence of abnormality, control of the control object is switched from the main controller to the subsidiary controller using the first-order time lag element attached to the switch unit thereby preventing the tracking of control data.
Inventors
👤 Masahiko Yamawaki
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-10-24 16:43
CPC Classifications
G; G05; G05B; G05B9/00; G05B9/02; G05B9/03
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
131 words
A multiplex control system including a main controller and subsidiary controller with different control characteristics connected through a switch unit to a control object, said main controller comprising an analog circuit and said subsidiary controller comprising a digital circuit, each of said main and subsidiary controllers comprising a PID operator for calculating proportional, differential and integral components; said system including a compensation means for eliminating output error caused by differences of the control characteristics between said main controller and said subsidiary controller; and said compensation means being so arranged that the integral term of said PID operator of said main controller is processed through a time lag operator of first order and added to the integral term of said PID operator of said subsidiary controller thereby to compensate an output error.
Claim 2
Dependent Claim
131 words
A multiplex control system including a main controller and subsidiary controller with different control characteristics connected through a switch unit to a control object, said main controller comprising an analog circuit and said subsidiary controller comprising a digital circuit, each of said main and subsidiary controllers comprising a PID operator for calculating proportional, differential and integral components; said system including a compensation means for eliminating output error caused by differences of the control characteristics between said main controller and said subsidiary controller; and said compensation means being so arranged that the integral term of said PID operator of said main controller is processed through a time lag operator of first order and added to the integral term of said PID operator of said subsidiary controller thereby to compensate an output error.
Claim 3
Dependent Claim
55 words
A multiplex control system according to claim 1, wherein said switch unit is additionally provided with a time lag element of first order so that said system is prevented from tracking the output signal from the PID operator of said main controller when said signal is interrupted momentarily during the operation of said switch unit.