Flow rate control using mass flow rate control device

A flow rate control device for controlling flow of a gas flowing through a flow path, comprising:

• a flow rate sensing unit that senses as a sensed flow rate a mass flow rate of a gas flowing through a flow path;
• a flow rate modifying unit that controls a flow rate of gas flowing through the flow path;
• and
• a control unit that performs feedback control of the flow rate modifying unit based on the sensed flow rate, and a target flow rate that is a target value for mass flow rate of the gas flowing on the flow path;
• a control data generating unit that generates the control data;
• wherein, while referring to first and second characteristic data,
• the first characteristic data including a plurality of first characteristic parameters respectively associated with mutually different mass flow rates wherein the first characteristic parameters reflect characteristics of the each flow rate control devices premised on a use of a prescribed gas designated as a standard,
• the second characteristic data that including a plurality of second characteristic parameters respectively associated with mutually different mass flow rates, wherein the second characteristic parameters reflect characteristics depending on the type of the gas premised on standard characteristics of the flow rate control devices,
• the control data generating unit generates the control parameter based on the first and second characteristic parameters in order to generate the control data;
• a first storage unit that stores the first characteristic data;
• and
• a second storage unit that stores the second characteristic data, wherein, data on the second storage unit can be swapped or updated more easily than that on the first storage unit;
• generating a corrected sensed flow rate based on the sensed flow rate and a control parameter that is determined based on at least one of the sensed flow rate and the target flow rate from among the plurality of control parameters;
• and
• wherein
• while referring to control data prepared individually for each of the flow rate control devices according to a type of the gas flowing through the flow path and including a plurality of control parameters respectively associated with mutually different mass flow rates, the control unit controls the flow rate modifying unit using a control parameter determined based on at least one of the target flow rate, the corrected sensed flow rate, and the sensed flow rate from among the plurality of control parameters.

A computer program product for controlling flow rate of a gas flowing on a flow path, wherein the computer program product includes:

• a computer-readable storage medium;
• and
• a computer program recorded onto the storage medium;
• wherein the computer program includes a module that, in a flow rate control device having a flow rate modifying unit that controls a flow rate of gas flowing through the flow path, and being configured to perform feedback control of a flow rate of a gas flowing on a flow path based on a target flow rate that is a target value for mass flow rate of the gas flowing on the flow path, and sensed flow rate that is a sensed mass flow rate of the gas flowing on the flow path, accomplishes a function by which, while referring to control data prepared according to a type of the gas flowing through the flow path and including a plurality of control parameters respectively associated with mutually different mass flow rates, wherein the control data is obtained by
• (i) providing first characteristic data that includes a plurality of first characteristic parameters respectively associated with mutually different mass flow rates, wherein the first characteristic parameters reflect characteristics of the provided flow rate control device premised on a use of a standard gas and saving the first characteristic data to a first storage unit of the flow rate control device provided in the step (a);
• (ii) providing second characteristic data that includes a plurality of second characteristic parameters respectively associated with mutually different mass flow rates, wherein the second characteristic parameters reflect characteristics depending on the type of the gas premised on standard characteristics of the flow rate control device;
• (iii) saving the second characteristic data to a second storage unit on which data can be swapped or updated more easily than that on the first storage unit;
• and, with reference to the first and second characteristic data,
• (iv) generating the control parameter based on the first and second characteristic parameters in order to generate the control data;
• (v) reading the first characteristic data from the first storage unit;
• (vii) reading the second characteristic data from the second storage unit;
• and
• (viii) generating a corrected sensed flow rate based on the sensed flow rate and a control parameter that is determined based on at least one of the sensed flow rate and the target flow rate from among the plurality of control parameters;
• and
• the flow rate modifying unit is controlled using a control parameter determined based on at least one of the target flow rate, corrected sensed flow rate, and the sensed flow rate from among the plurality of control parameters.