FR2807200A1 - METHOD AND DEVICE FOR CONTROLLING AT LEAST ONE ELECTROMAGNETIC CONSUMER - Google Patents

Abstract

Method and device for controlling an electromagnetic consumer such as an electromagnetic valve supplied from a power supply installation (9) and from an element such as a capacitor (20) storing a charge. The state of charge of the element (20) is detected and used. This state of charge (UC) of the element (20) is detected and exploited before the actuation of a consumer (2-5), during it or after it.

Description

The present invention relates to a method of

  control of at least one electromagnetic consumer, in particular an electromagnetic valve or valve supplied by an energy supply installation and by an element accumulating an electric charge, process according to which

  tect the state of charge of the element and we use it.

  The invention also relates to a device for

  control of at least one electromagnetic consumer, in particular

  an electromagnetic valve supplied from a

  power supply installation and an accumulator

  mulating an electric charge, including an installation

  to detect and exploit the state of charge of the element.

  STATE OF THE ART Processes and devices are known

  type defined above. They are used to order a consumer

  electromagnetic sensor including a solenoid valve, for

  order the fuel dosage in an internal combustion engine. To allow the consumer to be connected in an accelerated manner, an element storing an electric charge is provided, in particular a capacitor. For

  the consumer's energy supply after the branch-

  Accelerated, an energy supply installation is used, in particular the vehicle's on-board battery. In the known device, the state of charge of the element is detected between the end of a first actuation and the start of the following actuation; this information is used to conclude that the control malfunctions. However, it was found that one could have in all cases an unequivocal distinction between the different defects of

  operation in all cases. Such malfunctions

  tction can be caused for example by the detachment

  supply lines with respect to the consumer, which creates an idle market or even a ground contact between the supply line and / or the consumer. If the consumer is a solenoid valve and if as already indicated

  used to control the metering of fuel in a gasoline engine

  internal bustion, it is important to be able to distinguish unequivocally these two malfunctions. While it is possible to continue operating the vehicle if the solenoid valve is operating without load, without causing any

  difficulty, in the event of a short circuit, continue to operate

  operating the vehicle risks with a high probability of damaging the engine. To avoid this situation, in both cases we advise against malfunctions,

  continue driving with the vehicle.

  Advantages of the invention The aim of the present invention is to remedy the drawbacks of known solutions and to this end relates to a method of the type defined above, characterized in that the state of charge of the element before a

  activation, during and / or after this activation of the consumer

  mateur. The invention also relates to a device of the type defined above, characterized in that the installation detects and uses the state of charge of the element before a

  activation, during and / or after this activation of the consumer

mateur.

  The invention offers the advantage of allowing

  safely tingling between an idle failure and a short circuit failure, which allows

  continue to operate safely when idling.

  This increases the availability of the vehicle.

  According to an exemplary embodiment, provision is made to compare the states of charge of the element before, during and / or after actuation of the consumer. This makes it easy to see if it is a no-load operation, since the state of charge of the element has practically not changed

  since the consumer does not take energy from the element.

  If moreover we compare the state of charge of the element during

  and / or after actuation of the consumer, at a limited value

  predetermined mite (threshold), which represents a certain state of discharge of the element, which it would have if the consumer functioned perfectly, we can also guarantee that it

there is a short circuit.

  According to other advantageous characteristics of the invention: - the consumer is supplied at the start of actuation during an accelerated connection phase from the element, after the connection phase during an attraction phase and after the phase attraction during a maintenance phase from the energy supply installation; we detect and use the state of charge of the element at

  start of actuation, at the start of the branch phase-

  ment and during the attraction and / or maintenance phase;

  - the state of charge of the element is determined by the detection

  tion and exploitation of the instantaneous voltage level of the element.

  Particularly advantageously, we de-

  tecte and we exploit the state of charge of the consumer between

  an attraction phase and a consumption maintenance phase

  tor. If there is a short circuit at the level of the consumer or of his supply line, the element will not be recharged between the attraction phase and the maintenance phase because the consumer short circuit cannot supply energy back to the element. This allows to conclude unequivocally

  and guaranteed to short circuit.

  Drawings The present invention will be described below from

  in more detail using exemplary embodiments

  shown in the accompanying drawings in which: - Figure 1 shows a device for controlling at least one electromagnetic consumer, - Figure 2 shows different timing diagrams of signals from the

Figure 1 device.

  Description of the exemplary embodiments

  The device according to the invention is preferably applied to internal combustion engines and in particular engines whose ignition is not controlled. In that case,

  the fuel is metered by electromechanical valves

  magnetic (or electromagnetic injectors) called here

  generally after "consumers". However, the invention is not limited to such an application; on the contrary she

  can be used for all electromagnetic consumers

ques switching quickly.

  In its application to internal combustion engines, in particular engines with uncontrolled ignition, the opening and closing times of the solenoid valve define the start of the injection or the end of the injection

fuel in the cylinder.

  Figure 1 gives all the elements of the device

  according to the invention necessary for the description. The mode of

  illustrated embodiment relates to a device applied to a

  four-cylinder internal combustion engine. At each con-

  a summator is associated with an injector and with each injector, a cylinder of the internal combustion engine. For internal combustion engines with a larger or smaller number of cylinders, there will be a corresponding number of injectors,

  switching elements and diodes.

  Figure 1 shows a device 1 for controlling at least one electromagnetic consumer. In the example of

  realization we have represented four consumers 2, 3, 4, 5.

  A first terminal 6 of consumers 2-5 is connected by a first switching element 7 (also called "high side" switch) and a diode 8 to a supply line in

energy 9.

  The diode 8 is mounted with its anode connected to the switching element 7 and its cathode connected to the first terminal 6 of consumers 2-5. The switching element 7 is preferably a power semiconductor; he can

  be a field effect transistor.

  The second respective terminal 10 of consumers

  2-5 is connected each time by a second switching element

  tion 11, 12, 13, 14 to a first terminal 15 'of a resistor 15. The switching elements 11-14 are preferably power semiconductors and in particular transistors with

  field effect. The switching elements 11-14 are equally

  called "low side" switches. The second terminal 15 '' of the resistor 15 is connected to the power supply terminal

in energy 9, here its mass.

  Each consumer 2-5 is associated with a diode

  16, 17, 18, 19. The anode terminal of diodes 16-19 is re-

  linked each time to the connection point V between the consumer 2-5 and the second switching element 11-14. The terminal of the cathode of diodes 1619 is connected to an element 20 storing

  an electric charge as well as a third element of commu-

  tation 21. The element 20 storing an electric charge is in particular a capacitor. The cathode terminals of the diodes

  16-19 are connected to the first terminal 21 'of the third element

  switching element 21. The second terminal 21 '' of the switching element 21 is connected by a diode 22 to the first terminal 6 of the consumers 25. The diode 22 is connected so that its anode is connected to the third switching element

  21 and its cathode at the first terminals 6 of consumers 2-

  5. The switching element 21 is preferably a semi

  power conductor and in particular a transistor with effect of

  field. This switching element 21 is also called commu-

  tator-amplifier. The terminal of the element 20 not turned towards the cathode of the diodes 16-19 is connected by the resistor 15 to the energy supply installation 9 in particular at

  the earth terminal of this power supply.

  The switching element 7 receives a signal

  control AH of a control unit 23. The switching element

  tion 11 receives a control signal AL1 from the control unit

  request 23; the switching element 12 receives a control signal AL2; the switching element 13 receives a signal

  AL3 command; the switching element 14 receives a

  control AL4 and the switching element 21 an AC control signal; all these signals are supplied by circuit 23. The first terminal 6 of consumers 2-5 and the

  cathode of diode 8 are connected to diode 24, the ca-

  thode is connected to the cathode of diode 8. The anode of the

  diode 24 is connected to the power supply installation

  gie 9 in particular at its earth terminal. Resistor 15 allows

  to determine the current flowing respectively through the

  summers ordered 2-5. For this, the control unit 23

  has an intensity measurement installation 25 with two

  connected to the two terminals 15 ', 15' 'of the resistor 15.

  The assembly shown makes it possible to measure the intensity using the resistor 15 when one of the switching elements

  11 to 14 is closed. You can also measure the current when

  that the switching elements 11-14 are open, because the closed switching means 7 allows current to pass through the consumers 25 and the corresponding diodes 16-19 and the element 20 through the resistor 15. Another resistor 26 is provided between a terminal of the installation

  power supply 9 and the switching element 7.

  Connections connect the two terminals of resistor 26 to

  another current measuring installation 27.

  The mounting of the consumer switching elements

  tors, diodes and capacitors is given only as

example.

  The process described below can also

  apply to other assemblies of the elements.

  FIG. 2a shows the timing diagram of the control signal AC of the switching means 21 as a function of time t. FIG. 2b shows the control signal AH of the switching means 7 as a function of time t. FIG. 2c shows the timing diagram of the control signal AL of one of the elements of

  switching 11-14. Figure 2d shows the intensity Iv cross

  the corresponding consumer 11-14. FIG. 2e shows the voltage Uc across the terminals of element 20 storing an electric charge as a function of time. We have represented here a cycle

  dosing performed by a solenoid valve.

  Each dosing cycle is subdivided into different

  your phases. In a rest phase R, the consumer 2-5 is cut by its switching element 11-14. The control signals AC, AH and Al are then at low potential. The switching elements 7, 21 and 11 to 14 are open so that the flow of current is blocked. No current flows through consumers 2-5. Element 20 is loaded at its

  maximum charging voltage U1. This corresponds for example-

  ple at a value of 80 volts while the voltage of the power supply installation 9 corresponds to a value of about 12 volts. In this connection phase E

  which follows the rest phase R, at the start of the control of the

  summing device, the switching means 11-14 are controlled

  prayed. For the start of the connection phase E, the signal AL intended for the low side switch 11-14 is set to high level. At the same time, the control line AC emits a high level signal to unlock the switching element 21, that is to say close it. The switching element 27 is not yet controlled (Figure 2b). The high side switch 7 always remains closed. This command causes the element 20 storing

  a load supplies a current passing through the switching element

  tation 21 also called amplifier switch, to the corresponding consumers 2-5, the switching element 11-14 associated with the consumer and the resistor 15. In this connection phase, the consumer current Iv increases very rapidly due to the voltage high applied to

  consumer. The connection phase E ends for example

  ple when the voltage Uc applied to element 20 reaches

  a U2 value lower than the U1 value. This branching phase

  E can also stop when the current Iv of the

  consumer reaches a predetermined value.

  In the attraction phase A which follows the connection phase, the consumer is supplied with energy by the energy supply installation 9 since the control signal AH has closed the switching means 7. The

  consumer can then be supplied alternately from

  shooting of the supply installation 9 and by the element 20.

  In the attraction phase A, the control signal AC of

  the switching element 21 is deleted so that this element

  switching 21 is blocked. The control signal AH of the switching element 7 is set high. The signal

  control element AL of the switching element 11-14 remains at the

  calf high so that this 11-14 switching element stays

  open. A current thus flows through the supply system.

  tation 9 through the resistor 26, the switching element 7 and the diode 8 to supply the consumers, the element

  switching 11-14 corresponding and resistor 15 and re-

  come to the power plant 9. By ordering

  dence the switching element 7 by the control signal AH the current Iv can be detected using the resistor 15 to set a predetermined value of the attraction current

  IA. This means that when the attraction current of the con-

  summator reaches the setpoint intensity IA, the switching element 7 is controlled to block it. When the current goes below the lower threshold, the side switch

high becomes again passing.

  When the switching element 7 is blocked, the circuit is coasting. The current then passes through the

diode 24.

  The attraction phase A ends when the control unit 23 notes the end of the attraction phase A. This can for example be the case when a switching instant is detected indicating that the armature of the electromagnet is in its new end position. If the detection of the switching instant does not find in a predetermined period that the armature of the electromagnet is in its end-of-travel position,

we consider that there is a defect.

  In the third phase, also called rapid extinction phase S, the control signal AL for

  the switching element 11-14 is set low. A neck-

  rant then passes through the diode 16-19 associated with the user, to the charge storage element 20;

  the energy supplied to the consumer is converted into this element.

  ment 20. The switching element 7 is thus controlled in

  its embodiment shown since it remains closed.

  In this rapid extinction phase S, the consumption current

  mateur IV decreases from the intensity of attraction IA to

  the intensity of maintenance IH. At the same time the voltage Uc increases

  mente, applied to element 20 at a value U3 higher than the value U2 but significantly below the value

  U1. The rapid extinction phase S ends when

  turns on the setpoint IH of the holding current.

  The energy released during the passage of the attraction current IA to the holding current IH is thus stored in the element 20. In a particularly advantageous manner, the passage of the

  attraction current to the holding current is rapid-

  because of the rapid extinction.

  This first rapid extinction phase S continues with a holding phase H. As for the attraction phase A, the control signal AL of the switching elements 11-14 remains at its high level, ie to say that the

  low side switch 11-14 associated with the consumer remains closed

  me. By opening and closing the switching element

  tion 7, regulate the current passing through the consumers 2-5

  at the holding value IH. The holding phase H remains

  served until the end of the injection, i.e. the duration

consumer activation.

  In the second rapid extinction phase 2S which follows the maintenance phase H, we open again

  the switching element 11-14 and the control element is closed

  mutation 7. In this phase of rapid extinction 2S, the cou-

  rant Iv in the consumer drops rapidly to zero. At the same time, the voltage Uc applied to element 20 increases by a lower value than in the rapid extinction phase S. In the two rapid extinction phases S, 2S, the value of the current Iv goes from a high level to a low level. In this phase the associated low side switch 11-14

  each time the consumer is ordered to block the pass-

  current wise. The energy released by the consumer is

  thus transferred to element 20.

  During the attraction phase A and the

  hold H, the intensity regulation is done by the

  clocked command of the switching element 7. When the switching element 7 is blocked, the freewheeling diode 24 is active. In these phases, the consumer current Iv

  slowly decreases. This results in a frequency of com-

weaker mutation.

  In phase Z or cylinder change phase

  After the second rapid shutdown phase 2S, there is no fuel metering. This means that the control signal AC for the switching element 21, the control signal AH for the switching element 7 and the control signal AL for the switching element 11-14 remain at one

  low voltage level and thus all switching elements

  tion are blocked. The current flowing through the consumer 2-

  thus remains equal to zero and the voltage across the element 20 remains at its value. In the end of cadence phase N, known per se,

  which follows the cylinder change phase Z, by the com-

  switching element 7 and side switch

  bottom 11-14 corresponding, element 20 recharges. In order

  dant cadence the switching element 11-14, the current Iv in the consumer is adjusted so as not yet to activate the consumer 2-5. The current can thus be measured using the resistor 15 and the current measuring installation 25. The switching element 11-14 is controlled in cadence until the voltage across the element 20

  step by step again reaches the value U1.

  Then there is a phase during which all the control signals are deleted and all the elements

  remain in their blocked state. This phase cor-

  again responds to the rest phase R. To determine the state of charge Uc of the element, the device 1 includes means 28 for determining the state of charge. This means 28 can be integrated into the control unit 23. The means 28 for determining the state of charge by

  example in the form of a voltage measurement installation, is

  linked to the element 20 in particular to the central socket 29 of a voltage divider 30; this voltage divider is connected by

  a terminal on the line between element 20 and the control element

  mutation 21 and its other terminal is connected to ground. Thus, on the voltage divider 30, the voltage Uc of the element 20 can be taken according to the division ratio established by the two resistors 31, 32. If the means for determining the load 28 resists an appropriate voltage, it is also possible to

  remove the voltage divider 30.

  By measuring and using the state of charge of

  element 20, we can then determine in a particular way

  particularly advantageous if there is contact with ground at

  level of a consumer and if for example the first branch

  chement 6 is no longer connected to the switching element 7. In this case of a fault also called idling, the control signals AC, AH, AL will be sent as described above but there will be no current Iv in the consumer. In addition, the voltage Uc across the element 20 remains at its ni-

  calf equal to U1 when the switching phase E begins.

  If on the contrary there is a contact with the ground in the branch on the bottom side of the consumer as indicated by an arrow in figure 1, the current Iv in the consumer increases, the voltage Uc across the element

  drops to its U2 value during the connection phase.

  As the consumer current Iv escapes however di-

  directly to ground, in the rapid extinction phase S which follows the attraction phase A, there can be no

  return of electrical energy to element 20. In the event of a short-

  circuit, the voltage Uc across the element 20 thus remains at the value U2. This makes it possible to know in a simple manner by entering and exploiting the state of charge of the element if there is a malfunction in the form of a step.

  no load or short circuit. It is also planned to detect

  ter and exploit the state of charge of element 20 before

  actuation, i.e. at the start of the branch phase-

  ment E during and / or after actuation of the consumer.

  The state of charge is entered in the

  start of connection phase E; it takes a second sai-

  at the latest at the end of the H maintenance phase.

  By paring these two values of the state of charge of the element 20, it can be determined whether the two values are different. In addition, it is also possible to compare the second value of the state of charge with a predetermined limit. The moments

  to determine the state of charge of the element 20 can thus

  if coincide with the start of the command of a low side switch 11-14 and the switching off of the corresponding switching element 11-14. We can also determine the state of

  charge after actuation of the consumer 2-5 also during

  during the attraction phase A, the rapid extinction phase S and the maintenance phase H. To compare the states of charge of the element

  , the device 1 includes a comparator 33 which can also

  They are also part of the control unit 23. The means of determining the state of charge 28 provides the comparator 33 with the state of charge of the element 20 at different times.

  annuities; this compares them and gives a comparison result

  reason to the control unit; this then determines whether there is a malfunction and the nature of this defect. The

  comparator 33 can further compare a state of charge provided

  nor by the determination means 28 to a predetermined limit

  born that can call the comparator. A limit value for the state of charge of element 20 is between the levels

voltage U1 and U2.

  In the event of contact with the ground of the consumer 2-5 by its branch on the high side, a maximum current passes through the resistor 26. The current measurement installation 27 notices this situation. Even in the event of a short circuit, it is not possible to continue driving safely. The device 1 thus makes it possible to distinguish at least in a

  safe between three fault situations.

  It is obviously also possible to determine

  ner the state of charge of the element 20 with the means 28 to

  other instants apart from phases E, A, S, H and four-

provide information to the comparator.

Claims (4)

CLAIMS ON) Method for controlling at least one electromagnetic consumer, in particular a solenoid valve or electromagnetic valve supplied by an energy supply installation and by an element accumulating an electric charge, method according to which the state of charge of the element and it is used, characterized in that the state of charge (Uc) of the element (20) is detected and used before an actuation, during and / or after this actuation- consumer (2-5).   2) Method according to claim 1, characterized in that the states of charge of the element (20) are compared with one another   before, during and / or after actuation of the consumer (2-   ). 3) Method according to claim 1, characterized in that the state of charge of the element (20) is compared after   consumer activation (2-5) to a pre-   determined. 4) Method according to claim 1, characterized in that the consumer (2-5) is supplied at the start of actuation during an accelerated connection phase (E) from the element (20), after the phase connection (E) during an attraction phase (A) and after the attraction phase (A) during a holding phase (H) from the installation power supply (9).    ) Method according to claim 1, characterized in that the state of charge of the element (20) is detected and exploited   at the start of actuation, at the start of the branch phase-   ment (E) and during the attraction and / or maintenance phase (A, H).   6) Method according to claim 1, characterized in that   the state of charge of the element (20) is determined by the detection   tion and operation of the instantaneous voltage level (Uc) of the element (20).   7) Method according to claim 1, characterized in that the consumer state of charge is detected and exploited   (2-5) between the attraction phase and the maintenance phase.   8) Control device for at least one elective consumer   tromagnetic, in particular an electromagnetic valve   mented from an energy supply installation and an element accumulating an electric charge, comprising an installation for detecting and exploiting the state of charge of the element, characterized in that the installation (23) detects and uses the state of charge (Uc) of the element (20) before actuation, during and / or after   this consumer activation (2-5).