Control system for a flexible fuel internal combustion engine

A control system for an engine comprising:

• a first fuel injector;
• a first connection connected with the first fuel injector;
• a first control unit connected with the first connection and programmed to generate a first pulse width, which in operation is delivered to the first fuel injector over the first connection to actuate the first fuel injector to introduce a first fuel;
• a second fuel injector;
• a second connection connected with the second fuel injector;
• a second control unit connected with the second connection and programmed to generate a second pulse width, which in operation is delivered to the second fuel injector over the second connection to actuate the second fuel injector to introduce a second fuel;
• and
• a communication bus allowing the first and second control units to exchange information;
• wherein the first control unit is further programmed to determine a total fuel energy amount to be introduced by the first and second fuel injectors and to transfer the total fuel energy amount to the second control unit over the communication bus,
• wherein the second control unit is further programmed to determine a first fraction of the total fuel energy amount to be from the first fuel and a second fraction of the total fuel energy amount to be from the second fuel, and
• wherein the first control unit transfers the total fuel energy amount to the second control unit over the communication bus, and the total energy amount is one of a first quantity of the first fuel and a second quantity of the second fuel.

A control system for an engine comprising:

• a first fuel injector;
• a first connection connected with the first fuel injector;
• a first control unit connected with the first connection and programmed to generate a first pulse width, which in operation is delivered to the first fuel injector over the first connection to actuate the first fuel injector to introduce a first fuel;
• a second fuel injector;
• a second connection connected with the second fuel injector;
• a second control unit connected with the second connection and programmed to generate a second pulse width delivered over the second connection to actuate the second fuel injector to introduce a second fuel;
• and
• a communication bus allowing the first and second control units to exchange information;
• wherein the first control unit is further programmed to determine a total fuel energy amount to be introduced by the first and second fuel injectors and to transfer the total fuel energy amount to the second control unit over the communication bus;
• wherein the second control unit is further programmed to determine a first fraction of the total fuel energy amount to be from the first fuel and a second fraction of the total fuel energy amount to be from the second fuel, and
• wherein the second control unit transfers at least one of the first fraction and the second fraction to the first control unit over the communication bus.

A control system for an engine comprising:

• a first control unit programmed to generate a first pulse width to actuate a first fuel injector to introduce a first fuel;
• a. second control unit programmed to generate a second pulse width to actuate a second fuel injector to introduce a second fuel;
• and
• a communication line allowing the first and second control units to exchange information;
• wherein the first control unit is further programmed to:
• determine a fuel mass as a function of engine operating conditions representative of a first quantity or the first fuel and a second quantity of the second fuel whereby a first energy amount of the first quantity equals a second energy amount of the second quantity within a predetermined range of tolerance;
• and
• transfer the fuel mass to the second control unit over the communication line;
• wherein the second control unit is further programmed to determine a fuel fraction as a function of at least one of the fuel mass, engine operating conditions, properties of the first fuel and properties of the second fuel, the fuel fraction representative of a third quantity of the first fuel and a fourth quantity of the second fuel, the first energy amount is equal to a sum of a third energy amount of the third quantity of the first fuel and a fourth energy amount of the fourth quantity of the second fuel within a predetermined range of tolerance;
• wherein the first pulse width is determined as a function of the third quantity of the first fuel and the second pulse width is determined as a function of the fourth quantity of the second fuel.