Temperature control simulation method and apparatus

• US 6,711,531 B1
• Filed: 08/09/1999
• Issued: 03/23/2004
• Est. Priority Date: 08/13/1998
• Status: Expired due to Fees

• Current Assignee: Kokusai Electric Co., Ltd.
• Original Assignee: Kokusai Electric Co., Ltd.
• Inventors: Tanaka, Kazuo, Urabe, Kenzo, Yamaguchi, Hideto
• Primary Examiner(s): Jones, Hugh
• Assistant Examiner(s): FERRIS III, FRED O
• Application Number:
  US09/369,926
• Time in Patent Office: 1,688 Days
• Field of Search: 700/31, 703/2, 703/6, 703/7
• US Class Current: 703/6
• CPC Class Codes: G06G 7/66 for control systems for optimisation G06G7/122

Abstract

A temperature control simulation method and apparatus for forming a temperature system simulation model on a computer, provide substantially the same response or simulation characteristics as a temperature change in an actual furnace, whereby a temperature control algorithm can be developed and the method or manner of manipulating the temperature control can be learned without using an actual furnace. A transfer function is determined which represents a relationship between a heater input and a temperature output. A temperature control simulation for a heating furnace is executed using the transfer function of a heating furnace as a transfer function that a temperature system simulation device uses.

Claims

1. A temperature control simulation method for simulating temperature control on a heating furnace equipped with a heater by using a temperature system simulation device, said method comprising:

determining transfer function means representative of a relationship between an input to said heater and a temperature of said heating furnace;

simulating temperature control on said heating furnace by using said transfer function means as a transfer function means of said temperature system simulation device; and

obtaining a temperature output as a temperature control result based on said input to said heater without using an actual furnace;

wherein said transfer function means comprises a parameter which changes over time in accordance with a temperature control process, and

wherein said temperature control process comprises a process of controlling a temperature of said heating furnace during a time when a boat is loaded into said heating furnace, and said parameter of said transfer function means which changes over time comprises a time constant.

2. The temperature control simulation method of claim 1, wherein said parameter which changes over time comprises a second order delay curve.

6. The temperature control simulation method according to claim 1, wherein said transfer function means comprises a plurality of transfer functions corresponding to a plurality of different temperature zones, and

wherein said plurality of transfer functions are switched to select an appropriate one corresponding to each of said plurality of temperature zones.

3. A temperature control simulation method for simulating temperature control on a heating furnace equipped with a heater by using a temperature system simulation device, said method comprising:

determining transfer function means representative of a relationship between an input to said heater and a temperature of said heating furnace;

simulating temperature control on said heating furnace by using said transfer function means as a transfer function means of said temperature system simulation device; and

obtaining a temperature output as a temperature control result based on said input to said heater without using an actual furnace,

wherein said heating furnace comprises a plurality of heating zones, and said heater comprises a plurality of heaters provided one for each of said plurality of heating zones, and said transfer function means comprises interference between said heating zones.

4. The temperature control simulation method according to claim 3, wherein said transfer function means is determined by:

measuring an output of said heating furnace when a stepped input is applied to one of said plurality of heaters;

repeating an operation of measuring an output of said heating furnace for all remaining heaters of said plurality of heaters; and

calculating said transfer function means based on said measured outputs of said heating furnace.

5. The temperature control simulation method according to claim 4, wherein said transfer function means is calculated from a stepped response of each of said plurality of heaters comprising:

measuring a temperature output of said heating furnace when a stepped input is applied to each of said plurality of heaters;

measuring a temperature output of each of said heaters when a constant input is applied to each of said heaters at the same point of time as when said stepped input is applied to calculate a change over time of said temperature output of each of said heaters; and

calculating said transfer function means based on said temperature output response value which is subtracted by said change over time of said temperature output of each of said heaters to cancel variations in a power supply which supplies electric power to said heaters.