CN110620019B - Hybrid DC contactor and on-line diagnosis system thereof - Google Patents
Hybrid DC contactor and on-line diagnosis system thereof Download PDFInfo
- Publication number
- CN110620019B CN110620019B CN201810632466.1A CN201810632466A CN110620019B CN 110620019 B CN110620019 B CN 110620019B CN 201810632466 A CN201810632466 A CN 201810632466A CN 110620019 B CN110620019 B CN 110620019B
- Authority
- CN
- China
- Prior art keywords
- switch
- voltage
- solid state
- contact switch
- state switch
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000003745 diagnosis Methods 0.000 title description 11
- 239000007787 solid Substances 0.000 claims abstract description 90
- 238000001514 detection method Methods 0.000 claims abstract description 17
- 239000004065 semiconductor Substances 0.000 claims description 28
- 238000011156 evaluation Methods 0.000 claims description 11
- 238000002405 diagnostic procedure Methods 0.000 claims description 8
- 230000000903 blocking effect Effects 0.000 claims description 6
- 239000003990 capacitor Substances 0.000 claims description 3
- 230000001419 dependent effect Effects 0.000 claims description 3
- 230000003111 delayed effect Effects 0.000 claims description 2
- 238000009966 trimming Methods 0.000 claims 1
- 238000000034 method Methods 0.000 description 13
- 230000008569 process Effects 0.000 description 10
- 230000002159 abnormal effect Effects 0.000 description 4
- 230000001276 controlling effect Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 230000009471 action Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000001960 triggered effect Effects 0.000 description 2
- 208000027418 Wounds and injury Diseases 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 230000005288 electromagnetic effect Effects 0.000 description 1
- 208000014674 injury Diseases 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H47/00—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current
- H01H47/22—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current for supplying energising current for relay coil
- H01H47/32—Energising current supplied by semiconductor device
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Keying Circuit Devices (AREA)
Abstract
The invention relates to a hybrid direct current contactor, comprising: a contact switch capable of providing a first current path; a solid state switch capable of providing a second current path in parallel with the first current path; control circuit, the control circuit can be set up to control the contact switch and/or the solid-state switch according to external signal, wherein, the control circuit includes: at least one voltage detection module which can be provided for detecting a voltage with respect to the contact switch, in particular a voltage at the contact switch; the first control module can be used for conducting the solid-state switch under the condition that the voltage acquired by the voltage acquisition module reaches a first threshold value. Thus, a reliable hybrid DC contactor with low power loss can be realized. The invention further relates to an online diagnostic system for a hybrid contactor.
Description
Technical Field
The invention relates to a hybrid direct current contactor. The hybrid direct current contactor comprises a contact switch and a solid state switch, wherein the contact switch is connected with the solid state switch in parallel. In addition, the invention also relates to an online diagnosis system and an online diagnosis method. Further, the invention also relates to a vehicle comprising the hybrid direct current contactor and an on-line diagnosis system thereof.
Background
Dc contactors are widely used in the electrical industry. Typically, the switching on and off of a current path between a direct current power supply and an electrical load is achieved with a direct current contactor, in particular by controlling the switching on and off of the contacts of the direct current contactor. However, the conventional dc contactor has a series of defects, in which contact bounce and contact adhesion are main factors affecting the performance thereof, and in particular, in the case of contact adhesion, equipment runaway may occur, and even mechanical accidents and personal injury accidents may also occur. Therefore, eliminating or reducing the risk of contact adhesion and diagnosing the current contact adhesion situation are all technical problems to be solved urgently.
The known main cause of contact adhesion is arcing or spark. Typically, when the circuit is opened or closed, as long as the voltage between the contacts exceeds a certain threshold, e.g., 15V, and the current being opened or closed exceeds a certain threshold, e.g., 0.5A, a large surge current is generated in the contact gap causing the contacts to stick, which is an arc. At present, the cost for controlling the arc occupies about 50% of the cost of the whole direct current contactor, and the solution of the problem of adhesion of the visible contacts is extremely significant.
Furthermore, one way to eliminate or reduce the risk of contact sticking is to diagnose the contactor off-line. This requires prior de-energizing of the system and then diagnosing whether the contacts are stuck. This does not adequately guarantee the real-time reliability of the contacts, requires additional time-consuming and labor-consuming work, and is also detrimental to the user experience.
Disclosure of Invention
The task of the invention is: provided is a reliable hybrid DC contactor with low power loss.
According to a first aspect of the invention, the object is achieved by a hybrid dc contactor. The hybrid DC contactor includes: a contact switch, preferably an electromagnetic contact switch, which is capable of providing a first current path; a solid state switch, preferably a semiconductor switch, said solid state switch being capable of providing a second current path in parallel with said first current path; a control circuit, the control circuit comprising: at least one voltage detection module which can be provided for detecting a voltage with respect to the contact switch, in particular a voltage at the contact switch; the first control module can be used for conducting the solid-state switch under the condition that the voltage acquired by the voltage acquisition module reaches a first threshold value.
The contact switch (which may also be referred to as a relay or a contactor) may be an electromagnetic contact switch, which generally comprises an iron core, a coil, an armature, contacts, etc. When a certain voltage is applied to two ends of the coil, a certain current flows through the coil, so that an electromagnetic effect is generated, and the armature is attracted to the iron core against the pulling force of the return spring under the action of electromagnetic force attraction, so that the movable contact and the stationary contact of the armature are driven to be attracted. When the coil is powered off, the electromagnetic attraction force is eliminated, and the armature returns to the original position under the reaction force of the spring, so that the movable contact is attracted with the original stationary contact. Thus, the circuit is attracted and released, and the aim of conducting and cutting off in the circuit is achieved. The opening and closing speed of such electromagnetic contact switches is generally slow (because mechanical bouncing typically occurs between the moving contact and the stationary contact, resulting in a generally long opening and closing process). If the contact opening and closing process is observed, it is found that an instantaneous large current, also known as an inrush current, will be generated during the bouncing of the contact. This is a safety hazard for the contact switch itself, and even for the entire electrical system. In order to be able to reduce the risk of contact sticking, a solid-state switch (also called a contactless switch) is connected in parallel to the dc contactor, so that the solid-state switch is first turned on before the dc contactor needs to be turned off, so that the voltage across the contacts of the dc contactor is clamped at the on-voltage of the solid-state switch, and then the dc contactor is turned off. In this way, since the voltage across the clamped contact is small (typically between 0.7V and 2V), arcing can be effectively prevented. Eventually, the solid state switch is turned off after the contacts are reliably opened. The closing process can also be implemented in a similar manner.
Here, the solid-state switch may be a semiconductor switch (hereinafter referred to as a first semiconductor switch), such as a MOSFET, an IGBT, or a triac, which has advantages of high switching speed and good control performance. However, with respect to the application of the semiconductor switch, a non-negligible problem is the power loss (generally accompanied by an increase in junction temperature) due to its own on-resistance. In high-power applications, the power loss is not negligible. Meanwhile, the on-resistance also changes continuously along with the change of junction temperature and passing current.
According to the invention, the control circuit can be provided for actuating the contact switches and/or the solid-state switches as a function of external signals. The control circuit can receive external control signals from an external controller (a motor controller, a battery controller, a whole vehicle controller or the like according to specific application scenes) to realize the control or opening and closing of the contact switch and/or the solid-state switch. In addition, according to the invention, the voltage distributed on the contact switch can be acquired in real time by arranging the voltage acquisition module, and meanwhile, the first control module can conduct the solid-state switch according to the voltage in real time. Triggering conduction if the voltage reaches a first threshold; otherwise, the switch is kept off. The first threshold value is here dependent on the type of first semiconductor switch selected. Advantageously, the first threshold value is related to the conduction threshold value of the selected first semiconductor switch. Of course, the first threshold value should also be chosen taking into account that the voltage across the contacts is at a level where no arcing risk occurs. On the one hand, the on-time of the first semiconductor switch is thereby further reduced, so that the power losses are further reduced. Because in conventional hybrid contact switches the semiconductor switch must be turned on before the contact switch is closed or opened, the semiconductor switch cannot be opened until the contact switch is actually closed or opened. On the other hand, by selecting a proper first threshold value, the contact switch can be reliably guaranteed to be conducted in advance under the condition that no arc is generated (or the risk of arc generation is low), then the voltage at two ends of the contact switch is kept at a low level through clamping of the semiconductor switch, the whole process is finally guaranteed not to be accompanied with arc generation, and the risk of contact adhesion is reduced.
According to the invention, the first control module may comprise a voltage dividing module which can be provided for setting the first threshold value such that the probability of arcing of the contact switch can be effectively reduced.
Furthermore, according to the invention, at least one input of the first control module is connected to at least one output of the voltage detection module, and one of the outputs of the first control module is connected to a gate or a gate of the solid-state switch.
The voltage dividing module may be a resistive voltage dividing module composed of at least two resistors. One of the resistors defines a voltage value on a control electrode (e.g., gate or gate) of the first semiconductor switch, and the other resistor is connected to the voltage acquisition module to acquire the voltage value on the contact switch. As described above, the resistor is dimensioned in consideration of the on-voltage of the first semiconductor switch and the arc-generating voltage of the contact switch, so that on the one hand the on-time of the first semiconductor switch is kept as short as possible and on the other hand the probability of the contact switch generating an arc is kept as low as possible. In addition, the first control module can further comprise a capacitor to realize the functions of dynamic adjustment, time delay and the like.
According to the invention, the control circuit may further comprise a second control module which can be provided for switching off the solid-state switch with a delay after the solid-state switch is switched on.
Furthermore, according to the invention, the second steering module comprises: a second semiconductor switch, preferably in the form of a MOSFET, an IGBT or a triac; and the delay module at least comprises a capacitor, wherein one output end of the delay module is connected with the grid electrode or the gate electrode of the second semiconductor switch. One of the outputs of the second control module is connected to a gate or a gate of the solid-state switch for the delayed control of the solid-state switch. The delay module triggers the second semiconductor switch in the second control module to be turned on after a predetermined delay time. With the second semiconductor switch turned on, the gate or gate of the solid state switch (i.e. the first semiconductor switch) is pulled to a low potential, in particular to ground, thereby turning off the solid state switch. Thereby, the action of the solid-state switch is ended.
In addition, the delay module can be realized by a special delay chip. Since the delay time directly influences the on time of the first semiconductor switch, the delay time cannot be too long on one hand, otherwise the power loss will become large and the semiconductor junction temperature will increase. On the other hand, as mentioned above, the contacts of the contact switch bounce during opening and closing, and thus the delay time cannot be too short, otherwise the contacts will not be completely opened or closed yet, and the semiconductor will be opened again, thereby causing undesirable surge currents and even arcs.
According to the invention, a regulating resistor, preferably a semiconductor resistor, is arranged on the second current path, in particular on the side of the solid-state switch facing away from the ground line. The adjusting resistor can play a role in protection, and particularly can effectively prevent overload of the solid-state switch under the condition of sudden overload of the system.
According to the invention, the voltage detection module can be guided in the form of a wire from the first current path, in particular from the side of the contact switch facing away from the ground line, to the first control module. Thereby, the voltage information across the contact switch contacts is transferred to the control circuit. The embodiments can be implemented in a responsive, simple arrangement, cost-effective manner.
According to the invention, after actuation of the contact switch and/or the solid-state switch, the contact switch and/or the solid-state switch is diagnosed online taking into account the voltage and/or the temperature of the solid-state switch and/or the current flowing through the solid-state switch. In this case, it is possible to diagnose faults, in particular adhesions, of the contacts of the contact switch and faults of the solid-state switch in real time on line, so that the risk of faults is reduced and the safety and reliability of the hybrid dc contactor are improved.
According to a second aspect of the invention, the object is achieved by an online diagnostic system. The online diagnostic system includes: the device comprises a switching device, at least one voltage detection module and an evaluation unit, wherein the switching device comprises at least one switching element, a control circuit which can be provided to operate the at least one switching element as a function of external signals, and the evaluation unit is connected to the voltage detection module for detecting a voltage detected by means of the voltage detection module with respect to the at least one switching element, in particular a voltage across the at least one switching element, wherein the evaluation unit diagnoses the at least one switching element online taking into account the voltage and/or a temperature of the at least one switching element and/or a current flowing through the at least one switching element.
According to the present invention, the online diagnostic system may include: at least one contactor, at least one voltage acquisition module, and at least one analysis processing unit, wherein the contactor comprises: a contact switch capable of providing a first current path; a solid state switch capable of providing a second current path in parallel with the first current path; a control circuit which can be provided for actuating the contact switches and/or the solid-state switches as a function of external signals; the evaluation unit is connected to the at least one voltage detection module for detecting a voltage detected by the at least one voltage detection module with respect to a contact switch and/or with respect to a solid-state switch, in particular a voltage at a contact switch and/or at a solid-state switch, wherein the evaluation unit controls the contact switch and/or the solid-state switch by sending the external signal to the control circuit, and wherein the evaluation unit diagnoses the contact switch and/or the solid-state switch online taking into account the voltage and/or the temperature of the solid-state switch and/or the current flowing through the solid-state switch.
The on-line diagnostic system is able to detect faults of the contact switch and/or the solid-state switch in real time on the basis of the acquired voltage information of the contact switch and/or the solid-state switch (in the case of normal operation, since the contact switch and the solid-state switch are connected in parallel, the voltage represents both the voltage applied to the contact switch and the voltage applied to the solid-state switch), and on the basis of the characteristics of the contact switch and the solid-state switch. Unlike conventional off-line diagnostic systems, the on-line diagnostic system is able to ascertain current device failures and further take safety measures, thereby improving the reliability of the system as a whole. The analysis processing unit sends on-line diagnosis instructions on the one hand, collects diagnosis information on the other hand, and finally makes diagnosis results. Of course, the online diagnostic system may also include a series of sensors that detect the operating state, such as voltage sensors, current sensors, and temperature sensors, and are input as input variables to the evaluation unit.
According to the invention, the analytical processing unit is configured with a contact closure diagnostic module which enables the following on-line diagnostics: turning on the solid state switch and closing the contact switch, diagnosing that the contact switch has been reliably closed if the voltage (the collected voltage of the contact switch and/or the solid state switch) is below a second threshold (e.g., 0.3V); if the voltage is above a third threshold (e.g., 0.6V) and/or the temperature rises, diagnosing that the contact switch is not reliably closed; and/or
The analysis processing unit is configured with a contact adhesion diagnostic module capable of performing on-line diagnostics as follows: turning on a solid state switch and turning off a contact switch, diagnosing that no blocking of the contact switch has occurred if the voltage is above a fourth threshold (e.g., 0.6V) and/or the temperature increases and/or the current increases; diagnosing that the contact switch stuck if the voltage is below a fourth threshold (e.g., 0.3V); and/or
The analysis processing unit is configured with a contact switch diagnostic module that enables the following on-line diagnostics: in the case of a solid state switch opening, first closing the contact switch and then opening the contact switch, diagnosing that the contact switch is faulty if the voltage is above a fifth threshold (e.g. 0.6V) before opening the contact switch after closing the contact switch; if the voltage is below a sixth threshold (e.g., 0.6V) after opening the contact switch, diagnosing that the contact switch is faulty; and/or
The analytical processing unit is configured with a solid state switch diagnostic module capable of performing on-line diagnostics as follows: in the case of a contact switch being opened, first turning on the solid state switch and then turning off the solid state switch, diagnosing that the solid state switch is faulty if the voltage is above a seventh threshold (e.g. 2V) before the solid state switch is turned off after the solid state switch is turned on; if the voltage is below an eighth threshold (e.g., 2V) after opening the solid state switch, then the solid state switch is diagnosed as faulty.
Here, it should be noted that the operation sequence of the solid-state switch and the contact switch may be any sequence unless the sequence is specifically indicated. For example, "turning on the solid state switch and turning on the contact switch" may be to turn on the contact switch after the solid state switch is turned on, or may be to turn on the contact switch after the contact switch is turned on, or may be to turn on the solid state switch and turn on the contact switch simultaneously. The selection of the thresholds is here directly dependent on the respective component type, in particular the on-voltage drop. Furthermore, the individual diagnostic modules can be understood as different functional modules, which can be combined in any desired manner in the actual application.
According to a third aspect of the present invention, the present invention also relates to an online diagnostic method for an online diagnostic system comprising: at least one contactor, at least one voltage acquisition module, and at least one analysis processing unit, wherein the contactor comprises: a contact switch capable of providing a first current path; a solid state switch capable of providing a second current path in parallel with the first current path; control circuit, which can be provided for actuating the contact switches and/or solid-state switches as a function of external signals, and wherein: collecting a voltage on the contact switch and/or on the solid-state switch, in particular a voltage on the contact switch and/or on the solid-state switch; the external signal is sent to the control circuit to operate the contact switch and/or the solid state switch, which is diagnosed online taking into account the voltage and/or the temperature of the solid state switch and/or the current flowing through the solid state switch.
According to the invention, the on-line diagnostic method may perform at least one of the following diagnostics:
-turning on a solid state switch and closing a contact switch, diagnosing that the contact switch has been reliably closed if the voltage is below a second threshold; if the voltage is above a third threshold and/or the temperature rises, diagnosing that the contact switch is not reliably closed;
-turning on a solid state switch and turning off a contact switch, diagnosing that no blocking of the contact switch has occurred if the voltage is above a fourth threshold and/or the temperature rises and/or the current rises; diagnosing that a blocking of the contact switch occurs if the voltage is below a fourth threshold;
-in case the solid state switch is opened, first closing the contact switch and then opening the contact switch, diagnosing that the contact switch is faulty if the voltage is above a fifth threshold value before opening the contact switch after closing the contact switch; diagnosing that the contact switch is faulty if the voltage is below a sixth threshold after opening the contact switch;
-in case the contact switch is opened, first turning on the solid state switch and then turning off the solid state switch, diagnosing that the solid state switch is faulty if the voltage is above a seventh threshold value before the solid state switch is opened after the solid state switch is turned on; if the voltage is below an eighth threshold after opening the solid state switch, then diagnosing that the solid state switch is faulty.
It should be noted that the description of the online diagnostic system is equally applicable to the online diagnostic method.
According to a fourth aspect of the invention, the invention also relates to a vehicle, in particular a new energy vehicle (e.g. a pure electric vehicle, a hybrid electric vehicle, etc.), comprising a direct current power supply, a load, a hybrid direct current contactor according to the invention and/or an on-line diagnostic system according to the invention, wherein the hybrid direct current contactor is capable of switching on or off an electrical connection between the direct current power supply and the load.
Drawings
The invention is explained in more detail below with the aid of the figures. In the figure:
Fig. 1 shows a schematic circuit arrangement of a hybrid dc contactor according to the invention together with a dc power supply and an external load;
fig. 2a shows a flow chart of the operation when the circuit is completed by the hybrid dc contactor according to the present invention;
Fig. 2b shows a flow chart of the operation when the circuit is opened by the hybrid dc contactor according to the present invention;
FIG. 3 shows a simplified schematic of a hybrid DC contactor in an on-line diagnostic system according to the present invention;
fig. 4a, 4b, 4c respectively schematically show an on-line diagnostic flow chart according to the invention.
Detailed Description
Specific embodiments of the invention will be described below with reference to the accompanying drawings, in which several embodiments of the invention are shown. It should be understood, however, that the invention may be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein; indeed, the embodiments described hereinafter are intended to provide a more complete disclosure of the present invention and to fully illustrate the scope of the invention to those skilled in the art. It should also be understood that the embodiments disclosed herein can be combined in various ways to provide yet additional embodiments.
It should be understood that the terminology used in the description is for the purpose of describing particular embodiments only, and is not intended to be limiting of the invention. All terms (including technical and scientific terms) used in the specification have the meanings commonly understood by one of ordinary skill in the art unless otherwise defined. Well-known functions or constructions may not be described in detail for brevity and/or clarity.
As used in this specification, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. The use of the terms "comprising," "including," and "containing" in the specification mean that the recited features are present, but that one or more other features are not excluded. The use of the phrase "and/or" in the specification includes any and all combinations of one or more of the associated listed items.
Although exemplary embodiments of the present invention have been described, it will be understood by those skilled in the art that various changes and modifications can be made to the exemplary embodiments of the present invention without departing from the spirit and scope of the invention.
The invention will now be elucidated in connection with the various figures. Fig. 1 shows a schematic diagram of the circuit arrangement of a hybrid dc contactor 1 according to the invention together with a dc power supply 7 and an external load 8. As is clear from the figures, the hybrid dc contactor 1 comprises: a solid state switch SSR in the form of a MOSFET, an electromagnetic contact switch EMR and a control circuit 2. Wherein the solid-state switch and the electromagnetic contact switch are connected in parallel. In normal operation, the dc power supply supplies power to an external load only through the electromagnetic contact switch EMR. That is, only the electromagnetic contact switch is closed, while the solid state switch is open. The MOSFET is only required to be operated during the two transitions of the electromagnetic contact switch being required to be switched from the closed state to the open state or vice versa.
The control circuit 2 is shown in the form of a schematic block diagram, which comprises, for example, a first control module 4, a second control module 6 and a voltage detection module 3. The control circuit is capable of obtaining an external control signal from an external controller (not shown here). The external control signal contains a switch control command for controlling the solid-state switch and the electromagnetic contact switch, and the switch control command can be automatically generated by a system or manually and actively input. For example, when the external control signal goes from low to high, it indicates that the circuit needs to be turned on, whereas when the external control signal goes from high to low, it indicates that the circuit needs to be turned off. It should be noted here that a plurality of different control commands may be represented by a combination of a plurality of levels. Four different control commands are represented, for example, by a combination of two levels. For example, two high levels indicate that two switches are on at the same time, two low levels indicate that two switches are off at the same time, and one high-low indicates that only one switch is on or off. Any number of level combinations are also contemplated herein to represent any number of control possibilities.
The invention is further elucidated below in connection with fig. 2a, 2 b. The flow chart shown in fig. 2a exemplarily depicts a specific manipulation flow when the circuit needs to be completed. First, the control circuit 2 obtains an external control signal from an external controller (not shown here) and determines: the external control signal is changed from low to high, so that the solid-state switch SSR and the electromagnetic contact switch EMR are simultaneously conducted according to preset control logic. It should be noted that, since the conduction speed of the solid-state switch is far faster than the closing speed of the electromagnetic contact switch contacts, although both are simultaneously controlled, the solid-state switch SSR is significantly earlier than the electromagnetic contact switch is closed, thereby clamping the voltage across the contacts (for example, the conduction voltage of the MOSFET is about 1V here), and thus realizing the arc-free closing process of the contacts. The solid state switch is then opened again after the contact fully closed process by a delay of 20 ms.
The flow chart shown in fig. 2b illustrates an exemplary specific manipulation flow when the circuit needs to be broken. First, the control circuit 2 obtains an external control signal from an external controller (not shown here) and determines: the external control signal goes from high to low, so that the electromagnetic contact switch EMR is first opened according to a predetermined control logic. The voltage detection module 3 receives the voltage across the electromagnetic contact switch EMR in real time and transmits the voltage to the first control module 4. As can also be seen from fig. 1, the first control module comprises a voltage dividing module consisting of two resistors, on the basis of which the real-time voltage across the electromagnetic contact switch EMR detected by the voltage detection module 3 can be connected via voltage division to the gate of the solid-state switch SSR. The solid state switch is self-turned on when the voltage applied to the gate exceeds the turn-on threshold. Here, it is exemplarily shown that the solid-state switch is turned on when a voltage exceeding 5V is acquired. Then, a delay of 10ms is performed, after which the solid state switch is turned off again. The delay function and the final opening of the solid-state switch are realized by a second control module. As can also be seen from fig. 1, the second steering module comprises: MOSFETs and delay circuits. By selecting a proper resistance value and capacitance value, the conduction of the MOSFET can be triggered after a delay of 10ms, and the MOSFET is connected with the grid electrode of the solid-state switch SSR, and the grid voltage of the solid-state switch SSR is pulled to the grounding line after the MOSFET is conducted, so that the disconnection of the solid-state switch SSR is triggered. This results in an arc-free opening of the contacts. It should be noted that, since during this opening process the solid-state switch SSR is only turned on after the electromagnetic contact switch EMR is opened and is turned on for only 10ms, this greatly shortens the on-time of the solid-state switch SSR, thus effectively reducing the power losses of the system. In addition, the control flow of the opening process of the electromagnetic contact switch can be referred to in the closing process of the electromagnetic contact switch, so that the on time of the solid-state switch is further reduced.
An on-line diagnostic embodiment according to the present invention is described in detail below in conjunction with fig. 3 and fig. 4a to 4 c.
Fig. 3 shows a simplified schematic of a hybrid dc contactor in an on-line diagnostic system according to the present invention. It can be seen that the solid state switch SSR and the electromagnetic contact switch EMR are connected in parallel. Here, for the purpose of on-line diagnostics, the voltage V 12 across the parallel circuit and the temperature T of the solid state switch SSR are exemplarily detected for supply to an analysis processing unit (not shown here). The basic principle of the on-line diagnosis according to the invention here consists in the distinction of solid-state switches and electromagnetic contact switches in terms of on-resistance. In general, the on-resistance of an electromagnetic contact switch when the contacts are closed is approximately between 0.1 and 0.2 milliohms, while the on-resistance of a solid state switch is on the order of hundreds of milliohms. That is, the on-resistances of the two differ by several orders of magnitude. As a result, in the case of a parallel connection, most of the current will flow via the electromagnetic contact switch, rather than the solid state switch, if both are conductive.
Fig. 4a, 4b, 4c respectively schematically show an on-line diagnostic flow chart according to the invention. Here, the on-line diagnosis process according to the present invention will be described in detail with an electric vehicle as an application scenario.
Fig. 4a shows an on-line diagnostic flow at power-up of the electric vehicle (i.e. when the electromagnetic contact switch is closed). To diagnose on-line whether the electromagnetic contact switch is indeed reliably closed, the solid state switch SSR is first turned on, then the voltage V 12 is collected in real time, and the voltage V 12 is compared with a value a, for example 0.3V (the magnitude of the value a is closely related to the specific application scenario, switch type, current magnitude, etc.), if the voltage V 12 is lower than 0.3V, it indicates that the electromagnetic contact switch is normal (reliably closed), otherwise it indicates that the electromagnetic contact switch is abnormal and alarms.
Fig. 4b shows an on-line diagnostic flow during operation of the electric vehicle (i.e. the electromagnetic contact switch has been closed for a longer time). In order to diagnose on line whether the contacts of the electromagnetic contact switch are stuck due to long-time operation, the solid state switch SSR is firstly turned on, then the electromagnetic contact switch is turned off (a direct current power supply should flow through the solid state switch to supply power to a load), the voltage V 12 is collected in real time, the voltage V 12 is compared with a value C, for example, 0.6V (the magnitude of the value C is closely related to the specific application scene, the switch type, the current magnitude and the like), if the voltage V 12 is higher than 0.6V, the contacts are not stuck, otherwise, the contacts are stuck, and an alarm is given. Therefore, the on-line diagnosis system can diagnose a series of faults such as contact adhesion and the like on line under the condition that the electric vehicle is kept in an operating state, and the electric vehicle does not need to stop operating. The method can improve the reliability and the safety of the system in real time, and simultaneously improves the user experience without complex offline operation.
Fig. 4c shows an on-line diagnostic flow during a shutdown of the electric vehicle (i.e., both the electromagnetic contact switch and the solid state switch remain open). The following operations are performed periodically (for example, every 10 minutes) in the following sequence: closing an electromagnetic contact switch, collecting a first voltage value, opening the electromagnetic contact switch, collecting a second voltage value, conducting a solid-state switch, collecting a third voltage value, opening the solid-state switch, and collecting a fourth voltage value. Diagnosing the contact switch as abnormal closing if the first voltage value is higher than a value E, for example 0.3V; diagnosing the presence of sticking of the electromagnetic contact switch contacts if the second voltage value is lower than a value F, for example 0.3V; diagnosing the solid state switch as abnormal closure if the third voltage value is above a value G, e.g. 2V; if the fourth voltage value is below a value H, e.g. 2V, the solid state switch is diagnosed as abnormal. Of course, any other sequence is conceivable here, for example, a manipulation in the following order: the method comprises the steps of conducting a solid-state switch, collecting a first voltage value, opening the solid-state switch, collecting a second voltage value, closing an electromagnetic contact switch, collecting a third voltage value, opening the electromagnetic contact switch and collecting a fourth voltage value. Of course, it is also conceivable to add the temperature and the current value of the solid-state switch together to the diagnostic process.
Although exemplary embodiments of the present invention have been described, it will be understood by those skilled in the art that various changes and modifications can be made to the exemplary embodiments of the present invention without departing from the spirit and scope of the invention. Accordingly, all changes and modifications are intended to be included within the scope of the present invention as defined by the appended claims.
Claims (19)
1. A hybrid dc contactor (1) comprising:
-a contact switch (EMR) capable of providing a first current path;
-a solid State Switch (SSR) configured as a first semiconductor switch, the solid state switch being capable of providing a second current path in parallel with the first current path;
-a control circuit (2) comprising: at least one voltage detection module (3) which can be provided for detecting a voltage with respect to the contact switch; a first control module (4) which can be provided for switching on the solid-state switch if the voltage detected by the voltage detection module reaches a first threshold value, wherein the first control module (4) comprises a voltage division module which can be provided for setting the first threshold value such that it is dependent on the switching-on threshold value of the selected first semiconductor switch and the probability of arcing of the contact switch can be effectively reduced.
2. Hybrid direct current contactor according to claim 1, characterized in that the control circuit can be arranged for operating the contact switches and/or solid state switches in dependence of an external signal (5).
3. Hybrid direct current contactor according to claim 1 or 2, characterized in that the contact switch (EMR) is constituted as an electromagnetic contact switch.
4. Hybrid direct current contactor according to claim 1 or 2, characterized in that at least one input of the first steering module (4) is connected to at least one output of the voltage acquisition module (3) and one of the outputs of the first steering module (4) is connected to a gate or gate of a solid State Switch (SSR).
5. Hybrid dc contactor according to claim 1 or 2, characterized in that the control circuit further comprises a second steering module (6) which can be arranged for switching off the solid state switch with a delay after the solid state switch is switched on.
6. Hybrid direct current contactor according to claim 5, characterized in that said second steering module (6) comprises: a second semiconductor switch; the delay module at least comprises a capacitor, wherein one output end of the delay module is connected with a grid electrode or a gate electrode of the second semiconductor switch,
One output end of the second control module is connected with a grid electrode or a gate electrode of the solid-state switch, so as to be used for controlling the solid-state switch in a delayed mode.
7. Hybrid dc contactor according to claim 1 or 2, characterized in that an adjusting resistor is arranged on the second current path.
8. Hybrid direct current contactor according to claim 1 or 2, characterized in that the voltage acquisition module (3) is guided from a first current path to the first steering module (4) in the form of a wire.
9. Hybrid direct current contactor according to claim 1 or 2, characterized in that after the contact switch and/or solid state switch is manipulated, the contact switch and/or solid state switch is diagnosed on-line taking into account the voltage and/or the temperature of the solid state switch and/or the current flowing through the solid state switch.
10. Hybrid dc contactor according to claim 1 or 2, wherein said voltage acquisition module is arranged for acquiring a voltage across a contact switch.
11. The hybrid dc contactor according to claim 6, wherein said second semiconductor switching device is configured in the form of a MOSFET, an IGBT or a triac.
12. The hybrid dc contactor according to claim 7, wherein a trimming resistor is provided on a side of the solid state switch facing away from the ground line.
13. The hybrid dc contactor according to claim 7, wherein said tuning resistor is a semiconductor resistor.
14. Hybrid direct current contactor according to claim 8, characterized in that the voltage acquisition module (3) is guided in the form of a wire from the side of the contact switch facing away from the ground wire to the first control module (4).
15. An online diagnostic system comprising: at least one contactor, at least one voltage detection module and at least one evaluation unit, wherein the contactor is configured as a hybrid dc contactor according to one of claims 1 to 14, the control circuit of the contactor being able to be provided for actuating the contact switch and/or the solid-state switch of the contactor as a function of an external signal, wherein the evaluation unit is connected to the at least one voltage detection module for detecting a voltage detected by means of the at least one voltage detection module with respect to the contact switch and/or with respect to the solid-state switch, wherein the evaluation unit actuates the contact switch and/or the solid-state switch by sending the external signal to the control circuit, and wherein the evaluation unit diagnoses the contact switch and/or the solid-state switch online taking into account a temperature of the voltage and/or the solid-state switch and/or a current flowing through the solid-state switch.
16. The on-line diagnostic system of claim 15, wherein the diagnostic system is configured to,
The analysis processing unit is configured with a contact closure diagnostic module that enables the following on-line diagnostics: turning on a solid State Switch (SSR) and closing a contact switch (EMR), -diagnosing that the contact switch has been reliably closed if the voltage is below a second threshold; -diagnosing that the contact switch is not reliably closed if the voltage is above a third threshold and/or the temperature rises; and/or
The analysis processing unit is configured with a contact adhesion diagnostic module capable of performing on-line diagnostics as follows: turning on a solid State Switch (SSR) and turning off a contact switch (EMR), -diagnosing that no blocking of the contact switch has occurred if the voltage is above a fourth threshold and/or the temperature rises and/or the current rises; -diagnosing that said contact switch is stuck if said voltage is below a fourth threshold; and/or
The analysis processing unit is configured with a contact switch diagnostic module that enables the following on-line diagnostics: in case the solid State Switch (SSR) is open, first closing the contact switch (EMR) and then opening the contact switch (EMR), -diagnosing that the contact switch is faulty if the voltage is above a fifth threshold before opening the contact switch after closing the contact switch; -diagnosing that the contact switch is faulty if the voltage is below a sixth threshold after opening the contact switch; and/or
The analytical processing unit is configured with a solid state switch diagnostic module capable of performing on-line diagnostics as follows: in the case of a contact switch (EMR) being turned off, first turning on a solid State Switch (SSR) and then turning off the solid State Switch (SSR), -diagnosing that the solid state switch is faulty if the voltage is above a seventh threshold before the solid state switch is turned off after the solid state switch is turned on; -diagnosing that the solid state switch is faulty if the voltage is below an eighth threshold value after opening the solid state switch.
17. An on-line diagnostic method for an on-line diagnostic system, the on-line diagnostic system comprising: at least one contactor, at least one voltage acquisition module and at least one analysis processing unit, wherein the contactor is configured as a hybrid direct current contactor according to one of claims 1 to 14, the control circuit of the contactor being configurable for manipulating the contact switches and/or solid state switches in dependence of external signals, and wherein the on-line diagnostic method comprises: collecting voltages with respect to the contact switches and/or with respect to the solid state switches; the external signal is sent to the control circuit to operate the contact switch and/or the solid state switch, which is diagnosed online taking into account the voltage and/or the temperature of the solid state switch and/or the current flowing through the solid state switch.
18. The on-line diagnostic method of claim 17, wherein the on-line diagnostic method is capable of performing at least one of the following diagnostics:
-turning on a solid state switch and closing a contact switch, diagnosing that the contact switch has been reliably closed if the voltage is below a second threshold; if the voltage is above a third threshold and/or the temperature rises, diagnosing that the contact switch is not reliably closed;
-turning on a solid state switch and turning off a contact switch, diagnosing that no blocking of the contact switch has occurred if the voltage is above a fourth threshold and/or the temperature rises and/or the current rises; diagnosing that a blocking of the contact switch occurs if the voltage is below a fourth threshold;
-in case the solid state switch is opened, first closing the contact switch and then opening the contact switch, diagnosing that the contact switch is faulty if the voltage is above a fifth threshold value before opening the contact switch after closing the contact switch; diagnosing that the contact switch is faulty if the voltage is below a sixth threshold after opening the contact switch;
-in case the contact switch is opened, first turning on the solid state switch and then turning off the solid state switch, diagnosing that the solid state switch is faulty if the voltage is above a seventh threshold value before the solid state switch is opened after the solid state switch is turned on; if the voltage is below an eighth threshold after opening the solid state switch, then diagnosing that the solid state switch is faulty.
19. Vehicle, characterized in that it comprises a direct current power supply (7), a load (8), a hybrid direct current contactor (1) according to one of claims 1 to 14 and/or an on-line diagnostic system according to claim 15 or 16, wherein the hybrid direct current contactor is capable of switching on or off an electrical connection between the direct current power supply and the load.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810632466.1A CN110620019B (en) | 2018-06-20 | 2018-06-20 | Hybrid DC contactor and on-line diagnosis system thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810632466.1A CN110620019B (en) | 2018-06-20 | 2018-06-20 | Hybrid DC contactor and on-line diagnosis system thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110620019A CN110620019A (en) | 2019-12-27 |
| CN110620019B true CN110620019B (en) | 2024-08-16 |
Family
ID=68920402
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810632466.1A Active CN110620019B (en) | 2018-06-20 | 2018-06-20 | Hybrid DC contactor and on-line diagnosis system thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110620019B (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103823502A (en) * | 2014-02-20 | 2014-05-28 | 中国北方车辆研究所 | Current-limiting hybrid power controller |
| CN103956297A (en) * | 2014-04-30 | 2014-07-30 | 深圳市汇川技术股份有限公司 | Large current contactor control circuit of low-speed electric vehicle |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101266888B (en) * | 2008-04-30 | 2010-07-07 | 哈尔滨工业大学 | A high-power mixed DC contactor and its control method |
| US8638531B2 (en) * | 2011-12-14 | 2014-01-28 | Eaton Corporation | Hybrid bi-directional DC contactor and method of controlling thereof |
| JP2015115173A (en) * | 2013-12-11 | 2015-06-22 | ケージーエス株式会社 | Dc opening/closing device |
| CN105977100B (en) * | 2016-06-30 | 2018-08-21 | 株洲中车时代电气股份有限公司 | A kind of control method and device of rail traffic D.C. contactor |
| CN106505627B (en) * | 2016-12-22 | 2020-05-15 | 北京天诚同创电气有限公司 | Photovoltaic converter system and control method thereof |
| CN107797056B (en) * | 2017-10-31 | 2019-05-31 | 苏州汇川联合动力系统有限公司 | Braking resistor circuit contactor adhesion detection system and method |
| CN108061853A (en) * | 2017-11-20 | 2018-05-22 | 山东鲁能智能技术有限公司 | The power switch contact adhesion detecting system and method for electric vehicle DC charging |
-
2018
- 2018-06-20 CN CN201810632466.1A patent/CN110620019B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103823502A (en) * | 2014-02-20 | 2014-05-28 | 中国北方车辆研究所 | Current-limiting hybrid power controller |
| CN103956297A (en) * | 2014-04-30 | 2014-07-30 | 深圳市汇川技术股份有限公司 | Large current contactor control circuit of low-speed electric vehicle |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110620019A (en) | 2019-12-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4618906A (en) | Hybrid solid state/mechanical switch with failure protection | |
| US8638531B2 (en) | Hybrid bi-directional DC contactor and method of controlling thereof | |
| JP6877338B2 (en) | Power control device and its method | |
| US11011903B2 (en) | Disconnecting device | |
| JP5002708B2 (en) | Current limiter-based resettable MEMS microswitch array | |
| US8569645B2 (en) | Magnetic actuator circuit for high-voltage switchgear | |
| WO2000079664A1 (en) | Electrical circuit breaker for protecting against overcurrents | |
| CN108886248B (en) | Relay-set | |
| US11984290B2 (en) | Circuit breaker | |
| US4454503A (en) | Transistor fault indicator | |
| CN110137902A (en) | One kind prevents flexible direct current power module by-pass switch from refusing combined floodgate circuit and method | |
| US10978259B2 (en) | Circuit breaker | |
| US20230141822A1 (en) | On-load tap changer and method for actuating an on-load tap changer | |
| CN110620019B (en) | Hybrid DC contactor and on-line diagnosis system thereof | |
| CN110506376B (en) | Electrical switching apparatus | |
| CN111971770A (en) | Separating device for interrupting a direct current in a current path and on-board electrical system of a motor vehicle | |
| EP1733470B1 (en) | Circuit device for operating a motor and corresponding method | |
| CN101552160B (en) | Circuit protecting switch with delay control device | |
| CN116742574A (en) | Power distribution system, solid-state circuit breaker and circuit protection method | |
| US10720293B2 (en) | Apparatus and method of preventing malfunction of circuit breaker in metal-clad and metal enclosed switchgear | |
| US20240355562A1 (en) | Dc circuit breaker | |
| SU1027820A1 (en) | Switching apparatus | |
| KR20240008949A (en) | Electrical switching devices and associated methods and switching systems | |
| CN118435069A (en) | Circuit arrangement for checking the switching-off capability of an electronic switch | |
| CN117096820A (en) | Solid-state power output control circuit and control method for airborne power distribution |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TG01 | Patent term adjustment | ||
| TG01 | Patent term adjustment |