FR2999361A1 - PARALLEL ASSEMBLY OF MULTIPLE HALF-BRIDGES IN THE FORM OF COMPONENTS OF H-BRIDGE CIRCUITS - Google Patents

Abstract

An arrangement (100) for supplying equipment (200) of a motor vehicle and having two half-bridges (111, 112, 121, 122) connected in parallel (111, 112, 121, 122) connected in parallel and each having two transistors. Each of the half-bridges (111, 112, 121, 122) is integrated in an H-bridge circuit component (110, 120) which has an integrated computing unit (113, 123) for activating or neutralizing the freewheel of the half integrated gate (111, 112, 121, 122) according to the indication of an activation signal.

Description

Field of the Invention The present invention relates to a mounting for the power supply of a piece of equipment of a motor vehicle. The invention also relates to a method for managing such an arrangement. STATE OF THE ART In the automotive industry, H bridge transistors are used for multiple applications. Due to the relatively sudden environmental conditions (temperature, temperature variations, humidity, etc.), it is used, for example, to control DC motors, in particular in the field of driving freedom (for example the controls throttling flaps, exhaust gas recirculation systems, variable valve controls, variable geometry turbochargers or the like) generally monolithic integrated circuits, hereinafter referred to as H-bridge, also called H-bridge, integrated, bridge component H or bridge H, which in addition to a number of switching transistor half-bridges also have internal control and monitoring functions, in particular for internal current limitation and for the automatic active freewheel. The internal limitation ensures that the current supplied by a half bridge of the H bridge to the connected components is automatically limited to a certain value (usually by PWM pulse width modulation control of the high side transistor. If the active freewheel is active, in the passive phase (high-side cut-off transistor) the internal freewheeling diode is short-circuited by the low-side transistor, which reduces the power loss. H (H-bridge IC circuit) comprises an internal unit to provide such functions which are also connected by an interface such as for example a bus interface (for example an SPI bus) .The interface makes it possible to read the configuration and the control of the H-bridge integrated circuits and the data An intelligent structure in the H-bridge integrated circuit presents however difficulties because the half-bridges of such integrated circuits of H bridge can not t be connected in parallel (inputs and outputs in parallel) because one can then have unwanted cross currents currents important between the different half-bridges, for example if in case of overcurrent, all the half-bridges are not not in current limiting synchronism (ie if they are not simultaneously connected or cut off. But in certain situations, for example for high intensities and / or high temperatures it is desirable to operate two or more such half-bridges in parallel. Precisely in the case of motor vehicles, there are in places very high temperatures but the higher the ambient temperature and the lower the power that half-bridges can provide to the connected units. Moreover, the power lost in the half-bridges is limited by the monolithic structure, in case of high current demand of the connected equipment or in the case of the use of such H-bridge integrated circuits, under strong conditions. At ambient temperatures, it is advantageous to connect two or more half-bridges in parallel. DESCRIPTION AND ADVANTAGES OF THE INVENTION For this purpose, the present invention relates to a mounting assembly for the power supply of an equipment of a motor vehicle comprising at least two half-bridges connected in parallel each having two transistors, each of the two half-bridges being integrated in a H-bridge circuit component which has an integrated computing unit for activating or neutralizing the active freewheel of an integrated half-bridge as a function of the activation signal. The invention makes use of the fact that a parallel connection of two half-bridges formed of H-bridge integrated circuits leads to unwanted transverse currents only if, in the case of over-current situation, all the half-bridges are not in synchronism. in intensity limiting mode because because of the automatic active freewheel, the low side transistor of the half-bridge switches to current limiting and thus forms a short circuit with a high side transistor of a parallel half-bridge without intensity limitation. Thus, by avoiding an active freewheel operation, it is possible to have a parallel connection.

The invention has the advantage of describing the possibility of operating in parallel two or more intelligent H-bridge half-bridge decks in motor vehicles. Nevertheless, the control and monitoring functions of the H-bridge integrated circuits remain preserved. The loss of power released in bridges H connected in parallel is reduced to a very low level. The invention proposes H-bridge integrated circuits making it possible to selectively neutralize the active free-wheel mode, which makes it possible to operate in parallel two or more half-bridges but in internal intensity limitation. The possibility of neutralization can be done by appropriate configuration of the internal calculation unit of the H-bridge integrated circuit, for example by the description of a configuration register, for example by an SPI bus.

The invention results in a lower (average) temperature of the electronics and a better efficiency. The possible temperature excursion is increased for transient power peaks. The (mean) dynamics of the system are improved and the application is more robust even at high ambient temperatures. Thanks to the higher power peaks, the equipment connected, for example, the throttle flap can also operate with better dynamics, which has a positive effect on the overall dynamics of the system. A typical H-bridge integrated circuit includes two or more half-bridges each with a medium tap and the connected equipment is connected between two mid-taps or between a center tap and the ground. For a half-bridge parallel connection, only one half-bridge or one or more other half-bridges are connected in parallel. Advantageously, the module to be powered can also be connected between two integrated bridge circuits H in which at least two half-bridges are connected in parallel. Advantageously, the active freewheel mode of the first half-bridge is neutralized only if at least one second half-bridge connected in parallel is in the current limitation.

Advantageously, the active freewheel mode of all half-bridges connected in parallel is activated or neutralized as a function of the current to be supplied to the connected equipment. This reduces the lost power generated by the active freewheel that has been neutralized.

Preferably, the active freewheel is activated and neutralized externally and for this, advantageously the bridge circuit H has a corresponding input. The input is performed separately or as part of a bus interface (eg SPI). Activation / deactivation can be done by writing / erasing an internal configuration register. Activation and neutralization of the freewheel is then preferentially done by a subordinate unit, preferably a microcomputer or a control device. According to a preferred development, in an operating mode, in particular for a reduced supply of power ("economic mode") of the connected equipment, all the half-bridges connected in parallel will be cut except for one of these, so to respond to this weak demand for power by a single half-bridge, optimally. For a higher power demand (power mode) according to another operating mode, other half-bridges are activated in parallel with the neutralized freewheel. A transition value at the appropriate threshold between the two modes of operation depends on the application or modules. For example, it is possible to calculate beforehand or with the loss powers the transient value which is advantageously recorded in a main unit. Preferably, the half-bridges are activated and neutralized externally and advantageously at least one H-bridge integrated circuit has an appropriate input. The input can be made separately or as part of a bus interface (eg SPI). The activation / deactivation can be done for example by the recording / deletion of an internal configuration register. A computing unit according to the invention, for example a control device of a motor vehicle is designed in programming technique to apply the method of the invention.

The implementation of the method in the form of a program is an advantageous solution because the costs generated are particularly reduced especially if it is a control device used also for other functions and that exists anyway.

Suitable data carriers for the computer program include floppy disks, hard disks, flash memories, EEPROMs, CD-ROMs, DVDs, and the like. You can also download a program via a computer network (Internet, Intranet or other).

Drawings The present invention will be described in more detail below with the aid of embodiments of motor vehicle equipment feed circuits shown schematically in the accompanying drawings, in which: - Figure 1 shows the mounting according to the invention of a preferred embodiment of power supply of an equipment, - Figure 2 shows the powers lost in the transistor freewheel diodes during operation of the equipment. DESCRIPTION OF EMBODIMENTS OF THE INVENTION FIG. 1 shows a preferred embodiment of an assembly 100 according to the invention for the power supply of a device 200. The equipment 200 is an electrical drive (current motor continuous M with a transmission) of an electric throttle device of a motor vehicle. The assembly 100 is part of the electrical throttling device that regulates the air supply of the intake manifold of a gasoline engine. This device comprises a throttle flap with electric motor and angular sensor. The engine control 10 calculates the necessary opening of the throttle flap according to the position of the accelerator pedal. The DC motor adjusts the throttle valve shaft by the transmission and thus controls the amount of air. By the precise metering of the air, the throttling device controls the torque supplied by the engine and thus the power supplied.

The assembly 100 comprises two H-bridge circuit components, identical to the integrated circuits 110, 120; each component having two half-bridges 111, 112 or 121, 122. Each H-bridge integrated circuit 110, 120 further comprises a computing unit 113, 123 for controlling the transistors of the half-bridges. The calculation unit controls the transistors of the half-bridges according to the indications applied to the control terminals 114, 114 ', 115, 115', 116, 116 'or 124, 124', 125, 125 ', 126, 126' for the signals applied to these terminals. Each of the bridge ICs H, 110, 120 has for each half-bridge a branch (indicated in the figure by a non-winning reference and with an award-winning reference) and in the present example, there are always two. Each of the transistors has a freewheeling diode in parallel. But it can also be an intrinsic freewheel diode (for example in the case of a MOS transistor) or separate elements (for example in IGBT components). The connections 114, 114 'or 124, 124' may be the control inputs for example to preset the switching times; in the case of connections 115, 115 'or 125, 125' it may be input and current limiting to preset a maximum allowed intensity; the connections 116, 116 'or 126, 126' are, for example, the freewheel inputs for neutralizing an active freewheel in the H 110 or 120 bridge integrated circuits. These connections are connected to the motor control unit 10 which in the context of the invention appropriately controls the circuit.

Each of the H-bridge integrated circuits 110, 120 of each half-bridge comprises an output terminal 119, 119 'or 129, 129' as a middle terminal between two transistors and on which the equipment to be powered is connected. In the illustrated arrangement, two half-bridges 111, 112 or 121, 122 are connected in parallel each time so that their input and output control connection is in parallel. The electric throttle device 200 is thus connected between the output terminals 119, 119 'on one side and those 129, 129' on the other side. Each of the H-bridge integrated circuits 110, 120 also has power supply terminals 117, 118 or 127, 128 for the power supply. These terminals are connected to the on-board network of the vehicle. The motor control unit 10 controls the circuit 100. According to a preferred development, for a reduced power demand (economy mode) applied to the electric throttling device 200, the connected half-bridges are cut in parallel 112, 122 (by setting the control time to zero); here it can be expected that all the control connections will not be connected in parallel so that some half-bridges remain unused.

This makes it possible to provide the low power demand by only the half bridges 111 and 121. For a higher power demand (power mode), the half bridges 112, 122 are activated in parallel and the freewheeling mode is neutralized. half bridges. The power threshold between the economy mode and the power mode is determined by the application. For example, Figure 2 shows lost power on the freewheeling diodes of the transistors as a function of PWM pulse width modulated control signal for the operation of an electric throttle device taken as a for example, PWM = 100% which means a permanent connection of the high side transistor of a half-bridge. The graph 301 gives the power lost for each time two half-bridges in parallel on both sides of the DC motor M of the electric throttling device. The graph 302 corresponds to the power lost in each case a half-bridge on both sides of the DC motor M of the electric throttling device. It can be seen that the two graphs intersect at point 303. For a PMW modulation of less than 303, the lost power 302 is smaller (here only one half-bridge works advantageous in economic mode) and for a PWM modulation greater than 303, the lost power 301 is lower (here the two half-bridge are advantageously operated in "power mode") .35 100 120 NOMENCLATURE OF THE MAIN ELEMENTS 110, 112, 123 119 ', 111, 113, 119, 200 121, 122 Circuit supply of equipment 129, 129 'Bridge component H Half-decks Integrated calculation unit Median outlets Equipment10

Claims (5)

CLAIMS 1 °) Assembly (100) for the power supply of an equipment (200) of a motor vehicle having at least two half-bridges (111, 112; 121, 122) connected in parallel each having two transistors, each of two half-bridges (111, 112, 121, 122) being integrated in an H-bridge circuit component (110, 120) which has a built-in computing unit (113, 123) for activating or neutralizing the active freewheel of an integrated half-bridge (11, 112, 121, 122) as a function of the activation signal. 2 °) Assembly (100) according to claim 1, characterized in that the integrated computing unit (113, 123) limits the current in the integrated half-bridge (111, 112; 121, 122). 3) assembly (100) according to claim 1, characterized in that the equipment (200) comprises two power supply terminals, one of which is connected to the central tap (119, 119 ', 129, 129') d at least two half-bridges (111, 112, 121, 122) connected in parallel. 4. Mounting (100) according to claim 3, characterized in that it comprises at least two other half-bridges (111, 112; 12 1, 122) connected in parallel each having two transistors, each of the other two half bridges (111, 112, 121, 122) being integrated in an H-bridge circuit component (110, 120), and another center tap (119, 119 ', 129, 129') of at least two further halves bridges connected in parallel (111, 112, 121, 122) are electrically connected. Mounting (100) according to claim 1, characterized in that the bridge component H (110, 120) has a terminal (116, 116 ', 126, 126') for externally activating and neutralizing the wheel. free of integrated half-bridge.6 °) Assembly (100) according to claim 1, characterized in that the equipment (200) is a DC equipment including a DC motor. 7) Method for managing a circuit (100) according to any one of claims 1 to 6, characterized in that in a first mode of operation, at least two half-bridges connected in parallel (111, 112; , 122) feed the equipment (200) and the active freewheel of at least two half-bridges (111, 112, 121, 122) is neutralized. 8) Method according to claim 7, characterized in that in the second mode of operation, only one of the half-bridges (111, 112, 121, 122) connected in parallel supplies the equipment (200). 9 °) Method according to claim 8, characterized in that the freewheel is not neutralized for at least two half-bridges (111, 112, 121, 122). Method according to claim 7, characterized in that the first or the second mode of operation are predefined as a function of a power lost on at least two half-bridges (111, 112, 121, 122) connected in parallel. 11 °) calculation unit (10) applying a method according to any one of claims 7 to 9, characterized in that in a first mode of operation, at least two half-bridges connected in parallel (111, 112; 122) feed the equipment (200) and the active freewheel of at least two half-bridges 111, 112, 121, 122) is neutralized. 12 °) Computer program comprising program codes for a calculation unit for applying a method according to one of claims 7 to 10 when the method is applied by a calculation unit in particular according to claim 11. 13 °) A machine-readable memory medium having a computer program according to claim 12.15