• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    Device for preventing a current overload to a transistor in a DC-DC converter circuit, comprising a protection circuit which determines when the current exceeds a threshold and, when the current exceeds the threshold, operates to turn off the transistor, the deactivation of the transistor being effective to reduce the operating frequency and / or the DC current of the DC-DC converter circuit.
    公开号:FR3026900A1
    申请号:FR1501961
    申请日:2015-09-22
    公开日:2016-04-08
    发明作者:Sanchez Yessica Fabiola Chavez；Rodriguez Mario Alejandro Rodriguez；Gonzalez Izcoati Emmanuel Sanchez
    申请人:Continental Automotive Systems Inc；
    IPC主号:
    专利说明:

    [0001] TECHNICAL FIELD This method relates to DC-DC converters, and more specifically to protection circuits for transistors of DC-DC converters. BACKGROUND OF THE INVENTION Accumulators (and sometimes multiple accumulators) are used to power various types of systems. Some examples of use of accumulators are to use accumulators to power the electric system of conventional internal combustion vehicles, the engine of electric vehicles or hybrid vehicles. Accumulators in these systems may be battery packs that provide voltages in the range of 12 to 400 volts. Accessories and other items (eg fuel injectors), which are used in the same vehicles, normally require voltages that are different from 200 to 400 volts. These voltages are normally supplied by a 12V accumulator or by a 24V accumulator network. A conversion system of this kind that can be used is a DC-DC converter. In some examples of DC-DC converters, the voltage can be switched from 12 volts to 48 volts (for example, to control fuel injectors). Other examples of transformation are possible.
    [0002] Although DC-DC converters have been used, they have problems and limitations in operation. The conversion circuit in the DC-DC converter uses, for example, normally transistors. Transistors can be damaged or destroyed when too much current is applied. Thus, for example, in some applications that use inductors, the inductances can become defective by introducing intense currents in the transistors that control the circuits. In other examples, output overloads or transient signals in the circuit control logic may result in too much current flowing through the transistors, possibly resulting in their destruction. Previous solutions have not entirely succeeded in solving the problems mentioned above.
    [0003] As a result, users have not been somewhat satisfied with these previous systems and solutions. BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the disclosure, reference is made to the following detailed description and the accompanying drawings, in which: FIG. 1 shows a diagram of a protection circuit according to various embodiments of the invention; invention; Fig. 2 shows a circuit diagram of a system that uses the protection circuit of Fig. 1 according to various embodiments of the present invention; Fig. 3 is a graph showing aspects of the operation of Fig. 1 and Fig. 2 according to various embodiments of the present invention; Those skilled in the art will understand that elements in the figures are illustrated for the sake of simplicity and clarity. It will further be understood that certain effects and / or stages can be described or represented in a particular order of appearance, while it goes without saying that this sequence precision is not really required. Those skilled in the art will also understand that the terms and expressions used herein have the ordinary meaning ascribed to these terms and expressions in their respective fields of research and study, except where precise meanings are given. have been mentioned in this memo. DETAILED DESCRIPTION Solutions that stop the operation of one or more channels of a high-voltage DC-DC converter at a time when the current reaches more than a threshold determined in advance are described herein. . In particular, a control transistor is deactivated, which is used by any of the channels so that an overcurrent state can not damage the transistor. The transistor remains in the off state for a set time, which ensures that the transistor survives the overcurrent state. In many of these embodiments, a determination is made as to when the current flowing in the main transistor exceeds a threshold determined in advance. When the current exceeds the threshold determined in advance, the transistor is deactivated. Disabling the transistor is effective in limiting the main switch and its power dissipation. Current flowing in significantly reduce Current limiting is effective to prevent damage to the transistor in an overcurrent state. The transistor is held in the OFF state until a time-out circuit resets the DC-DC converter to the initial state. Maintaining the transistor in the off state is additionally effective to significantly reduce the duty cycle (on-time) and operating frequency of the master switch, and thereby reduce power dissipation. In still other aspects, the overcurrent condition may be caused by a faulty inductance in the DC-DC converter circuit. One way to detect this overcurrent state is to compare a reference voltage with a voltage proportional to the current flowing in the transistor. This comparison is made using an electronic circuit arranged as a comparator. The comparator output signal is used to reset the channel memory lock and disable the master switch. The lock output could also be used as a fault status indication sent to a control micro-unit. In some aspects, the DC-DC converter controls a device on the vehicle. In some examples, the device is a fuel injection device. Other examples of devices are possible. Referring now to Figure 1 and Figure 2, there is described an example of a protection circuit 102 disposed in a converter 100 DC-DC. The protection circuit 102 comprises a first resistor 104 (R1999), a second resistor 105 (R2000), an operational amplifier 106 (U3), a first capacitor (C1) 107, a third resistor 111 (2001), a second operational amplifier (U2) 108, a first NAND gate 109, and a second NAND gate 110. The NAND gates 109 and 110 are latched. The DC-DC converter 100 has an input circuit 120, an output circuit 130, a control circuit 140, a time-out circuit 150, a current feedback circuit 160, a memory 170 of channel, a transistor 190, a NAND gate 192, a bipolar transistor 93, a resistor 194, and a capacitor 195. The input circuit 120 includes an accumulator 122, a capacitor 124, a resistor 126, and an inductor 128. The circuit 130 output includes a capacitor 132, a switch 134 and a load 136. The load 136 may be a vehicle accessory in one example. In another example, the load may be a fuel injector. Other examples are possible.
    [0004] The control circuit 140 comprises a first transistor 141, a second transistor 142 and a third transistor 143, a capacitor 144 and resistors 145, 146 and 147. The time-out circuit 150 comprises an operational amplifier 151, a resistor and capacitors 153 and 154. The current feedback circuit 160 includes resistors 161, 162 and 163 and capacitors 164 and 165, and an operational amplifier 166. The channel memory 170 includes NAND gates 171, 172, 173. and 174. The transistor 190 is inverter mounted and is coupled to the NAND gate 192 to the protection circuit 102, the input circuit 120, and the output circuit 180. In some aspects of the operation of the circuitry of FIG. 1 and FIG. 2, the accumulator 122 produces a voltage and a current.
    [0005] Current flows into inductor 128 and is stored there. Current of inductance 128 goes to control circuit 140 when transistor 143 is closed. The current flows to the shunt resistor 161 by creating a voltage at the node 167 of the current feedback circuit 160. When this voltage exceeds a value determined in advance, the output of the operational amplifier 166 of the current feedback circuit 160 goes to a low logic value. The low value at the output of the operational amplifier 166 resets the latch of the channel memory 170. In particular, the output of the NAND gate 172 goes high logic, the output of the next NAND gate 173 goes to a logic low, and the output of the next NAND gate 174 goes to a logic high if the other input of the gate 174 is set to a logic high level (the validation input). This logic high level coming from the NAND gate 174 is retransmitted to the control circuit 140. This in turn activates the transistor 142. Activation of the transistor 142 turns off the control transistor 143. As a result, current no longer flows through the path from inductor 128 to current feedback circuit 160. Instead, the current goes to the output 130. If the inductor 128 has a zero current, negative voltage at the output of the inductor (this state is called "return"), the diode 193 is biased in the direction direct, and this allows the capacitor 153 to discharge. The protection circuit 102 is in this example configured with several stages and in the first stage the amplifier 106 may be a comparator LM2903 configured as a non-inverting amplifier in one example. Vshunt is connected to the current detection block of the DC / DC converter, that is, which passes into the control transistor 143. This stage amplifies the voltage of the shunt approximately 11 times. These other amplifications are possible. The second stage of the protection circuit in this example is the comparator 108, when the amplified Vshunt goes through the threshold of the reference voltage of 2.5V, the output goes to OV and is maintained at 5V otherwise. Other values are possible. The third stage of the protection circuits 102 is an S-R latch made of two fast switching NAND gates (NAND gate 109 and 110). When the output of the comparator 108 goes to OV, the latch is reset by causing the outputs (Q and 0 to switch logic states.) Q- is also referred to as "negative Q" in this specification.
    [0006] Q is normally in the high state, while Q. is in the low state. When an overcurrent state is detected, Q goes low and Q- goes high. Q is connected to transistor 190 (which in one example is an NMOS which enables / disables the "return" detection.) When Q is in a high state, transistor 190 is closed and "return" detection is enabled, the 100 DC / DC converter thus operating normally. When Q is low, transistor 190 opens, thereby disabling the "return" detection. This effectively cuts the operating frequency of the circuit of Figure 2 to a minimum. Thus, this forces the control circuit 140 to remain disconnected for as long as the voltage at the RC network (capacitor 153 and resistor 152) of the timeout circuit 150 is above the threshold (for example 2.5 volts ). Q- is connected to a transistor 197 (e.g., a digital NPN), which can reset the latch of the channel memory 170, which in turn turns the control transistor 143 to the off state. This effectively limits the maximum current that can pass through transistor 143 and inductance 128. Finally, and when the time-expander comparator 30 of the DC / DC converter circuit goes to OV, the latch of the Channel memory 171 is reset and everything is ready for the next cycle. Finally, the timeout circuit 150 changes to have an output at O. This sets the memory circuit latch 170 and a new operation cycle begins. Finally, and when the output of the timeout comparator 151 changes to OV, the latch (NAND gate 110) of the protection circuit 102 is reset and all of the components of the DC converter 100 / DC are ready for the next cycle.
    [0007] Referring now to FIG. 3, examples of application of the present solutions are described. The example of FIG. 3 uses two circuits (i.e., channels), each channel having a circuit according to FIG. 2. A first current 302 (from inductor 128) of the first channel is the correct behavior of a non-defective inductance. But, the second inductance is defective and produces the waveform 304 of the current. This is limited by the comparison of the waveform 306 to the threshold 308 due to the operation of the protection circuit 102. If there were no protection circuit 102, the current waveform 304 would have an overcurrent and the transistor 143 would be damaged or destroyed. Waveform 306 shows the output signal of a non-negative amplifier 106. The waveform 310 is part of the waveform 304 and represents the time the transistor remains in the off state even if the current in the defective coil drops to zero amp.
    [0008] Preferred embodiments of this invention are described herein, including the best known mode of the inventors for carrying out the invention. It goes without saying that the illustrated embodiments are only exemplary, and should not be construed as limiting the scope of the invention. The present invention relates to a method for preventing a current overload in a transistor used in a DC-DC converter circuit, the method comprising: determining when the current flowing in the transistor exceeds a threshold determined at in advance, and, when the current exceeds the threshold determined in advance, deactivate the transistor, the deactivation of the transistor being effective to significantly limit the current flowing in the transistor, the limitation of the current being effective to prevent damage to the transistor in a state of overcurrent; maintaining the transistor in the off state until a time-out circuit resets the DC-DC converter circuit to the initial state, being additionally effective to reduce the on-state time (duty cycle-DC) and frequency to prevent damage to the transistor due to switching power losses. Preferably, the DC-DC converter controls a device on the vehicle. Preferably, the device is a fuel injection device. Preferably, determining whether the current flowing in the transistor exceeds a predetermined threshold comprises comparing a voltage associated with the transistor to a voltage threshold using a comparator. Preferably, if the current flowing in the transistor exceeds a threshold determined in advance comprises comparing a voltage associated with the transistor to a voltage threshold using a comparator. Preferably, the method further comprises sending a fault status indication to a control unit. Preferably, the overcurrent state is caused by a faulty inductance of the DC-DC converter circuit. Preferably, disabling the transistor includes resetting a channel memory lock to the initial state. The present invention also relates to a device that is configured to prevent current overload to a transistor that is used in a DC-DC converter circuit, the device comprising: a protection circuit that determines when the current, passing through the transistor, exceeds a threshold determined in advance and, when the current exceeds the threshold determined in advance, operates to turn off the transistor, the deactivation of the transistor being effective to significantly reduce the operating frequency and / or the DC current of the DC-DC converter circuit, the deactivation of the current limiting transistor passing through the transistor, the current limiting being effective to prevent damage to the transistor in an overcurrent state, so that the transistor is maintained in a deactivated state by the protection circuit until a Time-out circuit resets the DC-DC converter circuit to the initial state, holding the transistor in the OFF state is additionally effective to prevent damage to the transistor from an over-current state. Preferably, the DC-DC converter controls a device on the vehicle. Preferably, the device is a fuel injection device. Preferably, determining whether the current flowing in the transistor exceeds a threshold determined in advance comprises comparing a voltage associated with the transistor to a voltage threshold using a comparator. Preferably, a fault status indication is sent to a control unit. Preferably, the overcurrent condition is caused by a faulty inductance of the DC-DC converter circuit. Preferably, the deactivation of the transistor is effective to reset a channel memory lock.
    权利要求:
    Claims (14)
    [0001]
    REVENDICATIONS1. A method of preventing current overload in a transistor used in a DC-DC converter circuit, the method comprising: determining when the current flowing in the transistor exceeds a predetermined threshold, and, when the current exceeds the threshold determined in advance, turn off the transistor, the deactivation of the transistor being effective to significantly limit the current flowing in the transistor, the current limiting being effective to prevent damage to the transistor in an overcurrent state ; maintaining the transistor in the off state until a time-out circuit resets the DC-DC converter circuit to the initial state, being additionally effective to reduce the on-state time (duty cycle-DC) and frequency to prevent damage to the transistor due to switching power losses. 25
    [0002]
    The method of claim 1, wherein the DC-DC converter controls a device on the vehicle. 30
    [0003]
    The method of claim 2, wherein the device is a fuel injection device.
    [0004]
    The method of claim 1, wherein determining whether the current flowing through the transistor exceeds a predetermined threshold comprises comparing a voltage associated with the transistor to a voltage threshold using a comparator.
    [0005]
    The method of claim 1 further comprising sending a fault status indication to a control unit.
    [0006]
    The method of claim 1, wherein the overcurrent condition is caused by a faulty inductance of the DC-DC converter circuit.
    [0007]
    The method of claim 1, wherein deactivating the transistor comprises resetting a channel memory lock to the initial state. 20
    [0008]
    A device which is configured to prevent current overload to a transistor which is used in a DC-DC converter circuit, the device comprising: a protection circuit which determines when the current flowing in the transistor exceeds a threshold determined in advance and, when the current exceeds the threshold determined in advance, operates to deactivate the transistor, the deactivation of the transistor being effective to significantly reduce the operating frequency and / or the DC current of the transistor circuit. DC-DC converter, the deactivation of the transistor limiting the current flowing in the transistor, the current limiting being effective to prevent damage to the transistor in an overcurrent state, so that the transistor is maintained in a state deactivated by the protection circuit until a time-out circuit re putting the DC-DC converter circuit in the initial state, the holding of the transistor in the OFF state being additionally effective to prevent damage to the transistor from an over-current state.
    [0009]
    9. Device according to claim 8, wherein the DC-DC converter controls a device on the vehicle.
    [0010]
    10. Device according to claim 9, wherein the device is a fuel injection device.
    [0011]
    The apparatus of claim 8, wherein determining whether the current flowing in the transistor exceeds a predetermined threshold comprises comparing a voltage associated with the transistor to a voltage threshold using a comparator.
    [0012]
    Apparatus according to claim 8, wherein a fault status indication is sent to a control unit.
    [0013]
    Apparatus according to claim 8, wherein the overcurrent condition is caused by a faulty inductance of the DC-DC converter circuit.
    [0014]
    The method of claim 8, wherein deactivating the transistor is effective to reset a channel memory lock.
    类似技术:
    公开号 | 公开日 | 专利标题
    FR3026900A1|2016-04-08|
    FR2959624A1|2011-11-04|VOLTAGE CONVERSION CIRCUIT CONTINUES
    EP3493357A1|2019-06-05|Charging circuit of an electric battery by means of a photovoltaic module
    FR3000323A1|2014-06-27|CUTTING POWER SYSTEM AND AIRCRAFT COMPRISING SUCH A SYSTEM
    FR2884079A1|2006-10-06|CONTROLLING A MOS TRANSISTOR
    EP2932588B1|2018-09-26|Circuit for comparison of a voltage with a threshold and conversion of electrical energy
    US10291118B2|2019-05-14|Power converter controller
    WO2009115555A1|2009-09-24|Device for controlling a power supply with dc dc splitting of the type including n interlaced paths
    EP2882087A1|2015-06-10|DC-DC converter with operation in discontinuous mode
    FR3035281A1|2016-10-21|
    WO2012107190A1|2012-08-16|Hysteretic control of an electronic device using a pulse-width modulated signal
    EP3633487A1|2020-04-08|Switching converter
    EP3087647B1|2021-04-28|Power controller with linear control of current peak limitation and with short-circuit protection
    EP3028356B1|2021-11-17|System for managing a supply voltage of an onboard electrical network of a motor vehicle
    FR3065129B1|2019-06-21|DECOUPAGE ENERGY CONVERTER CONTROLLED IN "CRETE LOAD" MODE IMPROVED
    FR2479590A1|1981-10-02|Protection circuit for power transistor with rapid response - compares signal representing transistor function with reference signal to control conduction interval
    FR3005806B1|2019-07-12|CIRCUIT AND METHOD FOR IMPROVING THE USE OF THE CAPACITY OF AN INTERMEDIATE CIRCUIT OF AN ELECTRICAL NETWORK ONBOARD IN A MOTOR VEHICLE
    WO2021250254A1|2021-12-16|Dc/dc voltage converter with precharging device
    EP3771055A1|2021-01-27|Device for detecting overcurrent in an electrical power circuit comprising a filtering means controlling the charge of a capacitor
    EP3843255A1|2021-06-30|Circuit for controlling the input impedance of a recovery device interface
    EP3425757B1|2021-06-02|Protective circuit for a power switch
    FR3091057A1|2020-06-26|Preload device and voltage converter comprising such a device.
    WO2020011768A1|2020-01-16|Method for triggering the changing of a transistor to the on state
    WO2020002266A1|2020-01-02|System comprising a power flow control device used to control the distribution of currents in a grid network and means for protecting said device
    FR2964274A1|2012-03-02|CUTTING CONVERTER
    同族专利:
    公开号 | 公开日
    US20160079748A1|2016-03-17|
    DE102015217836A1|2016-03-17|
    US9647445B2|2017-05-09|
    KR101771803B1|2017-08-28|
    ITUB20153703A1|2017-03-17|
    KR20160033061A|2016-03-25|
    FR3026900B1|2021-04-30|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    DE3302864C1|1983-01-28|1983-11-03|Euchner & Co, 7022 Leinfelden-Echterdingen|Circuit arrangement for protecting a contactlessly controllable semiconductor switch|
    DE4034569A1|1990-10-31|1992-05-07|Vdo Schindling|CIRCUIT DESIGNED AS A BLOCK WITH AT LEAST ONE SEMICONDUCTOR SWITCH FOR SWITCHING A LOAD|
    DE102005045889B4|2005-09-26|2008-11-20|Continental Automotive Gmbh|Polyphase DC-DC controller and method for operating a polyphase DC-DC controller|
    JP5889723B2|2012-06-07|2016-03-22|ルネサスエレクトロニクス株式会社|Semiconductor device|DE102014214840A1|2014-07-29|2016-02-04|Bayerische Motoren Werke Aktiengesellschaft|Device for monitoring a high-voltage electrical system of an electrically operated vehicle for the presence of an overload|
    US9698691B2|2015-06-04|2017-07-04|Dialog SemiconductorLimited|Circuit and method for maximum duty cycle limitation in switching converters|
    KR102322489B1|2019-12-11|2021-11-08|주식회사 유라코퍼레이션|Over current protection circuit and over current protection method using the same|
    CN112072616B|2020-09-02|2021-09-14|珠海格力电器股份有限公司|IPM over-current detection circuit and electric appliance|
    法律状态:
    2016-04-08| EXTE| Extension to a french territory|Extension state: PF Ref document number: PF |
    2016-09-21| PLFP| Fee payment|Year of fee payment: 2 |
    2017-09-28| PLFP| Fee payment|Year of fee payment: 3 |
    2018-09-24| PLFP| Fee payment|Year of fee payment: 4 |
    2019-09-25| PLFP| Fee payment|Year of fee payment: 5 |
    2020-09-14| PLFP| Fee payment|Year of fee payment: 6 |
    2020-09-25| PLSC| Search report ready|Effective date: 20200925 |
    2021-09-21| PLFP| Fee payment|Year of fee payment: 7 |
    优先权:
    申请号 | 申请日 | 专利标题
    US14/489,247|US9647445B2|2014-09-17|2014-09-17|Over-current protection circuit and method|
    [返回顶部]