Assembly consistency detection circuit and device of DC / DC converter

Abstract

The invention discloses an assembly consistency detection circuit and device of a DC / DC converter, the DC / DC converter comprises at least two boost circuits arranged in parallel, and each boost circuit comprises a power tube; the assembly consistency detection circuit of the DC / DC converter at least comprises a DC voltage source, a DC current source and a processing unit. The direct-current voltage source and the direct-current current source are respectively connected with each power tube in parallel; the direct-current voltage source is used for providing fixed voltage signals for the power tubes; the direct current source is used for providing a fixed current signal for each power tube; the power tube outputs a detection signal according to the fixed voltage signal and the fixed current signal; and the processing unit is used for acquiring the detection signals output by the power tubes and detecting the assembly consistency among the power tubes according to the detection signals and the fixed current signals. The power tubes of the booster circuits are detected, and the temperature rise change of the power tubes is judged according to the output detection signals and the fixed current signals, so that the assembling consistency of the DC / DC converter is accurately judged.

Description

Technical Field

[0001] The present invention relates to the technical field of assembly detection, and in particular to an assembly consistency detection circuit and device for a DC / DC converter. Background Art

[0002] The commonly used high-power fuel cell DC / DC converters on the market are Boost converters or Buck converters, in which power switch tubes are indispensable in the conversion circuit. In the past, IGBTs were often used as power switch tubes, which have the disadvantages of high loss and low power density. With the increasing maturity of SiC products, DC / DC converters currently use power tubes, including MOS tubes and diodes, and the proportion of power tubes is increasing.

[0003] However, in the process of producing and installing DC / DC converters, we cannot judge with the naked eye that after installation, when the heat dissipation of the power tube is not good, it will affect the efficiency and temperature rise of the whole machine. Therefore, how to accurately judge the installation consistency of the power tube and reflect its heat dissipation performance has become an urgent problem that needs to be solved. Summary of the invention

[0004] The present invention provides an assembly consistency detection circuit and device for a DC / DC converter, which can accurately determine the assembly status of power tubes in each boost circuit through the assembly consistency detection circuit for the DC / DC converter.

[0005] According to one aspect of the present invention, there is provided an assembly consistency detection circuit for a DC / DC converter, wherein the DC / DC converter comprises at least two boost circuits arranged in parallel, wherein the boost circuit comprises a power tube;

[0006] The assembly consistency detection circuit of the DC / DC converter comprises at least a DC voltage source, a DC current source and a processing unit;

[0007] The DC voltage source and the DC current source are respectively connected in parallel with each of the power tubes;

[0008] The DC voltage source is used to provide a fixed voltage signal for each of the power tubes;

[0009] The DC current source is used to provide a fixed current signal for each of the power tubes;

[0010] The power tube outputs a detection signal according to the fixed voltage signal and the fixed current signal;

[0011] The processing unit is used to obtain the detection signal output by each of the power tubes, and detect the assembly consistency between the power tubes according to each of the detection signals and the fixed current signal.

[0012] Optionally, the processing unit is further used to obtain a forward voltage drop curve of each of the power tubes according to each of the detection signals and the fixed current signal, and to determine assembly consistency between each of the power tubes according to each of the forward voltage drop curves.

[0013] Optionally, the assembly consistency detection circuit of the DC / DC converter includes an oscilloscope, a voltage collection end of the oscilloscope is electrically connected to each of the power tubes, a current collection end of the oscilloscope is electrically connected to the positive electrode of the DC current source, and an output end of the oscilloscope is electrically connected to the processing unit;

[0014] The oscilloscope is used to collect the detection signal of the power tube and the fixed current signal output by the DC current source, and output them to the processing unit.

[0015] Optionally, the oscilloscope includes a trigger unit, which is electrically connected to the DC current source, and is used to collect a fixed current signal at the output end of the DC current source, and when the fixed current signal is greater than a preset trigger current signal, collect a detection signal of the power tube and a current signal output by the DC current source.

[0016] Optionally, the assembly consistency detection circuit of the DC / DC converter further includes an oscilloscope voltage acquisition unit, a receiving end of the oscilloscope voltage acquisition unit is electrically connected to each of the power tubes, and an output end of the oscilloscope voltage acquisition unit and a positive electrode of the DC current source are both connected to the oscilloscope;

[0017] The oscillographic voltage acquisition unit is used to collect the detection signal of each power tube.

[0018] Optionally, the power tube includes a MOS tube;

[0019] The drain of the MOS tube is electrically connected to the positive electrode of the DC current source and the positive electrode of the DC voltage source, and the source of the MOS tube is electrically connected to the negative electrode of the DC current source and the negative electrode of the DC voltage source;

[0020] The processing unit is used to obtain the detection signal output by each of the MOS tubes, and detect the assembly consistency between the MOS tubes according to each of the detection signals and the fixed current signal.

[0021] Optionally, the power tube includes a diode;

[0022] The anode of the diode is electrically connected to the positive electrode of the DC current source and the positive electrode of the DC voltage source, and the cathode of the diode is electrically connected to the negative electrode of the DC current source and the negative electrode of the DC voltage source;

[0023] The processing unit is used to obtain the detection signal output by each of the diodes, and detect the assembly consistency between the diodes according to each of the detection signals and the fixed current signal.

[0024] Optionally, the assembly consistency detection circuit of the DC / DC converter further includes a current sensor;

[0025] The first end of the current sensor is electrically connected to the positive electrode of the DC current source, the second end of the current sensor is electrically connected to the positive electrode of the DC voltage source and the power tube respectively, and the third end of the current sensor is connected to the oscilloscope;

[0026] The current sensor is used to collect a fixed current signal in real time and output it to the power tube and the oscilloscope.

[0027] Optionally, the assembly consistency detection circuit of the DC / DC converter further includes a first resistor, and the first resistor is arranged between the positive electrode of the DC voltage source and the positive electrode of the DC current source.

[0028] According to another aspect of the present invention, a DC / DC converter assembly consistency detection device is provided, characterized by comprising the DC / DC converter assembly consistency detection circuit according to any one of the above aspects.

[0029] The technical solution of the embodiment of the present invention is a DC / DC converter assembly consistency detection circuit, wherein the DC / DC converter includes at least two boost circuits arranged in parallel, and the boost circuit includes a power tube; the DC / DC converter assembly consistency detection circuit includes at least a DC voltage source, a DC current source and a processing unit; the DC voltage source and the DC current source are respectively connected in parallel with each power tube; the DC voltage source is used to provide a fixed voltage signal for each power tube; the DC current source is used to provide a fixed current signal for each power tube; the power tube outputs a detection signal according to the fixed voltage signal and the fixed current signal; the processing unit is used to obtain the detection signal output by each power tube, and detect the assembly consistency between each power tube according to each detection signal and the fixed current signal. The power tube of each boost circuit in the DC / DC converter is detected by the DC / DC converter assembly consistency detection circuit, and the temperature rise change is judged according to the output detection signal and the input fixed current signal, thereby reflecting the assembly status of each power tube, and then accurately judging the assembly consistency of the DC / DC converter.

[0030] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0032] Figure 1 A schematic diagram of the structure of a boost circuit of a DC / DC converter provided by an embodiment of the present invention;

[0033] Figure 2 A schematic diagram of installing a power tube provided by an embodiment of the present invention;

[0034] Figure 3 A schematic diagram of the structure of an assembly consistency detection circuit for a DC / DC converter provided by an embodiment of the present invention;

[0035] Figure 4 A schematic diagram of the structure of another DC / DC converter assembly consistency detection circuit provided by an embodiment of the present invention;

[0036] Figure 5 A diode forward voltage drop curve diagram provided by an embodiment of the present invention;

[0037] Figure 6 A schematic diagram of the structure of a consistency detection device for a DC / DC converter assembly provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0038] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0039] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0040] Figure 1 A schematic diagram of a boost circuit of a DC / DC converter provided by an embodiment of the present invention is provided. Figure 2 A schematic diagram of installing a power tube provided by an embodiment of the present invention is shown in FIG. Figure 3 A schematic diagram of a DC / DC converter assembly consistency detection circuit provided by an embodiment of the present invention, Figure 4 A schematic diagram of the structure of another DC / DC converter assembly consistency detection circuit provided by an embodiment of the present invention, Figure 5 A diode forward voltage drop curve diagram provided by an embodiment of the present invention, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, this embodiment can be applied to detecting the assembly status of a DC / DC converter 100. The DC / DC converter 100 includes at least two boost circuits 101 arranged in parallel, and the boost circuit 101 includes a power tube 102. The assembly consistency detection circuit 103 of the DC / DC converter includes at least a DC voltage source 104, a DC current source 105 and a processing unit 106. The DC voltage source 104 and the DC current source 105 are respectively connected in parallel with each power tube 102. The DC voltage source 104 is used to provide a fixed voltage signal for each power tube 102. The DC current source 105 is used to provide a fixed current signal for each power tube 102. The power tube 102 outputs a detection signal according to the fixed voltage signal and the fixed current signal. The processing unit 106 is used to obtain the detection signal output by each power tube 102, and detect the assembly consistency between each power tube 102 according to each detection signal and the fixed current signal.

[0041] The DC / DC converter 100 includes at least two boost circuits 101 connected in parallel. Each boost circuit 101 includes a power tube 102. Each power tube 102 includes a MOS tube and a diode. Since the power tube 102 generates a lot of heat during use, insulation and heat dissipation need to be considered when installing the power tube 102. Figure 2 As shown, a water cooling design is usually used for cooling. A layer of insulating heat sink 12 is placed between the power tube 102 and the water cooling plate 11, and then a layer of thermal conductive silicone grease 13 with a thickness of 0.1mm to 0.2mm is applied on both sides of the insulating heat sink 12 to fill the gap between the power tube 102 and the insulating heat sink 12, thereby enhancing the heat dissipation capacity of the power tube 102. Since a large number of power tubes 102 are arranged in the DC / DC converter 100, if the scattering of the power tube 102 is not good, it will affect the efficiency of the whole machine. Therefore, when producing and installing the DC / DC converter 100, it is necessary to judge the heat dissipation performance of each power tube 102, detect the assembly consistency between each power tube 102, and then judge whether the power tube 102 is in close contact with the insulating heat sink 12, so as to facilitate subsequent maintenance. In the embodiment of the present invention, by Figure 3 As shown, the assembly consistency detection circuit 103 of the DC / DC converter is used for detection. The assembly consistency detection circuit 103 of the DC / DC converter at least includes a DC voltage source 104, a DC current source 105 and a processing unit 106; the DC voltage source 104 and the DC current source 105 are respectively connected in parallel with each power tube 102, and the processing unit 106 is connected to the DC voltage source 104, the DC current source 105 and each power tube 102. The DC voltage source 104 is used to provide a fixed voltage signal for each power tube 102; the DC current source 105 is used to provide a fixed current signal for each power tube 102; to ensure that the power tube 102 can work normally, the current output by the DC current source 105 can be a fixed value between 20A-120A, and can be 30A by way of example. The voltage output by the DC voltage source 104 can be 20V, and the current value output by the DC current source 105 and the voltage value output by the DC voltage source 104 can be set according to the conduction conditions of the MOS tube and the diode, which is not specifically limited in the embodiment of the present invention.

[0042] like Figure 5 As shown, with the help of the forward characteristic of the diode, the forward voltage drop is different at different temperatures under the same current signal. The DC / DC converter assembly consistency detection circuit 103 can detect both the MOS tube and the diode in each boost circuit 101. For example, Figure 1As shown, the DC / DC converter 100 includes four boost circuits 101 which are arranged in parallel and have the same structure. The boost circuit 101 includes a first boost circuit 1011, a second boost circuit 1012, a third boost circuit 1013 and a fourth boost circuit 1014. The first boost circuit 1011 includes a first MOS transistor M1 and a first diode D1. The second boost circuit 1012 includes a second MOS transistor M2 and a second diode D2. The third boost circuit 1013 includes a third MOS transistor M3 and a third diode D3. The fourth boost circuit 1014 includes a fourth MOS transistor M4 and a fourth diode D4. Figure 3 As shown, Figure 3 In the figure, the assembly consistency detection circuit 103 of the DC / DC converter is schematically used to detect the MOS tube. The structure and connection method of the assembly consistency detection circuit 103 of the DC / DC converter for detecting the remaining MOS tubes in the DC / DC converter 100 are the same. Different MOS tubes can be connected to different DC / DC converters for detection. The assembly consistency detection circuit 103 of each DC / DC converter has the same parameter settings to ensure that the detection of each MOS tube is under the same detection conditions, or different MOS tubes can be connected to the assembly consistency detection circuit 103 of the same DC / DC converter for detection; the assembly consistency detection circuit 103 of the DC / DC converter detects the diode in the same way, and no further details are given again. When the assembly consistency detection circuit 103 of the DC / DC converter detects the MOS tube, since a diode is provided in the MOS tube structure, under a fixed current signal, after the MOS tube is turned on, the temperature will rise rapidly, and the forward voltage drop at both ends of the MOS tube will be different at different temperatures. Therefore, the first MOS tube M1, the second MOS tube M2, the third MOS tube M3 and the fourth MOS tube M4 are detected in sequence, and then the processing unit 106 receives the first detection signal of the first MOS tube M1, the second detection signal of the second MOS tube M2, the third detection signal of the third MOS tube M3 and the fourth MOS tube M4 in sequence. The fourth detection signal is combined with the fixed current signal to generate a first forward voltage drop change curve of the first MOS tube M1, a second forward voltage drop change curve of the second MOS tube M2, a third forward voltage drop change curve of the third MOS tube M3, and a fourth forward voltage drop change curve of the fourth MOS tube M4, and then the coincidence of the first forward voltage drop change curve, the second forward voltage drop change curve, the third forward voltage drop change curve, and the fourth forward voltage drop change curve is judged. If the coincidence is high, it is considered that the assembly consistency of each MOS tube is good. If the coincidence is low, it is considered that the assembly consistency of each MOS tube is out of tolerance and needs to be reinstalled and repaired;

[0043] Similarly, if Figure 4As shown, when the assembly consistency detection circuit 103 of the DC / DC converter detects the diode, due to the forward characteristic of the diode, under a fixed current signal, after the diode is turned on, the temperature will rise rapidly, and the forward voltage drop across the diode will be different at different temperatures. Therefore, the first diode D1, the second diode D2, the third diode D3 and the fourth diode D4 are detected in sequence, and then the processing unit 106 receives the fifth detection signal of the first diode D1, the sixth detection signal of the second diode D2, the seventh detection signal of the third diode D3 and the eighth detection signal of the fourth diode D4 in sequence, and generates the first diode D1 in combination with the fixed current signal. The fifth forward voltage drop change curve of the second diode D2, the sixth forward voltage drop change curve of the second diode D3, the seventh forward voltage drop change curve of the third diode D3 and the eighth forward voltage drop change curve of the fourth diode D4 are then judged for the coincidence of the fifth forward voltage drop change curve, the sixth forward voltage drop change curve, the seventh forward voltage drop change curve and the eighth forward voltage drop change curve. If the coincidence is high, it is considered that the assembly consistency of each diode is good. If the coincidence is low, it is considered that the assembly consistency of each diode is out of tolerance. When the forward voltage drop of the diode is larger under the same current signal, it is considered that the contact effect between the diode and the insulating heat sink 12 is poor, and reinstallation and maintenance are required. By testing each power tube 102 in the DC / DC converter 100, the temperature rise and assembly consistency can be accurately reflected.

[0044] The embodiment of the present invention sets up an assembly consistency detection circuit of a DC / DC converter, uses a DC voltage source to provide a fixed voltage signal for each power tube; a DC current source provides a fixed current signal for each power tube; each power tube outputs a detection signal according to the fixed voltage signal and the fixed current signal; a processing unit is used to obtain the detection signal output by each power tube, and accurately detects the assembly consistency between each power tube according to each detection signal and the fixed current signal.

[0045] Optional, continue to refer to Figure 3 and Figure 4 The processing unit 106 is further used to obtain the forward voltage drop curve of each power tube 102 according to each detection signal and the fixed current signal, and determine the assembly consistency between the power tubes 102 according to each forward voltage drop curve.

[0046] Among them, for the detection signal output by each power tube 102, the detection signal includes a voltage detection signal. Exemplarily, when the MOS tube is detected, the processing unit 106 generates a first forward voltage drop curve, a second forward voltage drop curve, a third forward voltage drop curve and a fourth forward voltage drop curve according to the fixed current signal, the first detection signal output by the first MOS tube M1, the second detection signal output by the second MOS tube M2, the third detection signal output by the third MOS tube M3 and the fourth detection signal output by the fourth MOS tube M4, respectively, and then merges the first forward voltage drop curve, the second forward voltage drop curve, the third forward voltage drop curve and the fourth forward voltage drop curve into the same coordinate system to perform coincidence judgment, and then judge the assembly consistency of the first MOS tube M1, the second MOS tube M2, the third MOS tube M3 and the fourth MOS tube M4.

[0047] Optional, continue to refer to Figure 3 and Figure 4 The assembly consistency detection circuit 103 of the DC / DC converter includes an oscilloscope 107, a voltage collection end of the oscilloscope is electrically connected to each power tube 102, a current collection end of the oscilloscope 107 is electrically connected to the positive electrode of the DC current source 105, and an output end of the oscilloscope 107 is electrically connected to the processing unit 106; the oscilloscope 107 is used to collect the detection signal of the power tube 102 and the fixed current signal output by the DC current source 105, and output them to the processing unit 106.

[0048] Among them, an oscilloscope 107 is also provided in the assembly consistency detection circuit 103 of the DC / DC converter. When detecting each power tube 102 in the DC / DC converter 100, the voltage acquisition end of the oscilloscope is electrically connected to each power tube 102, the current acquisition end of the oscilloscope 107 is electrically connected to the positive pole of the DC current source 105, and the output end of the oscilloscope 107 is electrically connected to the processing unit 106; so that the oscilloscope 107 can automatically trigger and save, save the voltage waveform of the currently detected power tube 102, that is, the detection signal of each power tube 102, and at the same time can also receive the fixed current signal output by the DC current source 105, and then output the value processing unit 106, the processing unit 106 processes and obtains the forward voltage drop curve of each power tube 102, and judges the assembly consistency between each power tube 102 according to each forward voltage drop curve.

[0049] Optional, continue to refer to Figure 3 and Figure 4 The oscilloscope 107 includes a trigger unit 108, which is electrically connected to the DC current source 105. The trigger unit 108 is used to collect the current signal at the output end of the DC current source 105, and when the current signal is greater than a preset trigger current signal, collect the detection signal of the power tube 102 and the current signal output by the DC current source 105.

[0050] Among them, a trigger unit 108 is provided in the oscilloscope 107, so that the trigger unit 108 is electrically connected to the DC current source 105. The trigger unit 108 is triggered by current. The trigger unit 108 is used to collect the fixed current signal at the output end of the DC current source 105, and when the fixed current signal is greater than the preset trigger current signal, exemplarily, the preset trigger current signal can be 10A, and the preset trigger current signal can be selected according to actual design requirements. When the fixed current signal is greater than 10A, the trigger unit 108 is in a starting state, thereby collecting the detection signal of the power tube 102 and the current signal output by the DC current source 105.

[0051] Optional, continue to refer to Figure 3 and Figure 4 The assembly consistency detection circuit 103 of the DC / DC converter also includes an oscilloscope voltage acquisition unit 109, the receiving end of the oscilloscope voltage acquisition unit 109 is electrically connected to each power tube 102, and the output end of the oscilloscope voltage acquisition unit 109 and the positive pole of the DC current source 105 are both connected to the oscilloscope 107; the oscilloscope voltage acquisition unit 109 is used to collect the detection signal of each power tube 102.

[0052] Among them, the assembly consistency detection circuit 103 of the DC / DC converter is also provided with an oscilloscope voltage acquisition unit 109, the receiving end of the oscilloscope voltage acquisition unit 109 is electrically connected to each power tube 102 respectively, and the output end of the oscilloscope voltage acquisition unit 109 and the positive pole of the DC current source 105 are both connected to the oscilloscope 107; the oscilloscope voltage acquisition unit 109 is used to collect the detection signal of each power tube 102, and then transmit it to the oscilloscope 107, so that the oscilloscope 107 can save the currently collected detection signal.

[0053] Optional, continue to refer to Figure 3 The power tube 102 includes a MOS tube; the drain of the MOS tube is electrically connected to the positive electrode of the DC current source 105 and the positive electrode of the DC voltage source 104, and the source of the MOS tube is electrically connected to the negative electrode of the DC current source 105 and the negative electrode of the DC voltage source 104; the processing unit 106 is used to obtain the detection signal output by each MOS tube, and detect the assembly consistency between each MOS tube according to each detection signal and the fixed current signal.

[0054] The power meter tube includes a MOS tube and a diode. When the assembly consistency detection circuit 103 of the DC / DC converter is used to detect each MOS tube, the drain of the MOS tube needs to be electrically connected to the positive electrode of the DC current source 105 and the positive electrode of the DC voltage source 104, and the source of the MOS tube needs to be electrically connected to the negative electrode of the DC current source 105 and the negative electrode of the DC voltage source 104, so that when the DC / DC converter 100 includes a first MOS tube M1, a second MOS tube M2, a third MOS tube M3 and a fourth diode D4, the first MOS tube M1, the second MOS tube M2, the third MOS tube M3 and the fourth MOS tube M4 are detected in sequence, and then the processing unit 106 receives the first detection signal of the first MOS tube M1, the second MOS tube M2, the third MOS tube M3 and the fourth MOS tube M4 in sequence. The first detection signal of the second MOS tube M2, the third detection signal of the third MOS tube M3 and the fourth detection signal of the fourth MOS tube M4 are combined with the fixed current signal to generate the first forward voltage drop change curve, the second forward voltage drop change curve, the third forward voltage drop change curve and the fourth forward voltage drop change curve in sequence, and then the coincidence of the first forward voltage drop change curve, the second forward voltage drop change curve, the third forward voltage drop change curve and the fourth forward voltage drop change curve is judged. If the coincidence is high, it is considered that the assembly consistency of each MOS tube is good. If the coincidence is low, when there is a MOS tube with a larger forward voltage drop under the same current signal, it is considered that the contact effect between the MOS tube and the insulating heat sink 12 is poor, and it is considered that the assembly consistency of each MOS tube is out of tolerance, and reinstallation and maintenance are required.

[0055] Optional, continue to refer to Figure 4 The power tube 102 includes a diode; the anode of the diode is electrically connected to the positive electrode of the DC current source 105 and the positive electrode of the DC voltage source 104, and the cathode of the diode is electrically connected to the negative electrode of the DC current source 105 and the negative electrode of the DC voltage source 104; the processing unit 106 is used to obtain the detection signal output by each diode, and detect the assembly consistency between each diode according to each detection signal and the fixed current signal.

[0056] When the assembly consistency detection circuit 103 of the DC / DC converter detects the diode, the first diode D1, the second diode D2, the third diode D3 and the fourth diode D4 are detected in sequence, and then the processing unit 106 receives the fifth detection signal of the first diode D1, the sixth detection signal of the second diode D2, the seventh detection signal of the third diode D3 and the eighth detection signal of the fourth diode D4 in sequence, and generates the fifth forward voltage drop change curve, the sixth forward voltage drop change curve, the seventh forward voltage drop change curve and the eighth forward voltage drop change curve in combination with the fixed current signal. Regarding the forward characteristics of the diode, under a fixed current signal, after the diode is turned on, the temperature will rise rapidly, and the forward voltage drop at both ends of the diode will be different at different temperatures, and then the fifth forward voltage drop change curve, the sixth forward voltage drop change curve, the seventh forward voltage drop change curve and the eighth forward voltage drop change curve are judged for their overlap. If the overlap is high, it is considered that the assembly consistency of each diode is good. If the overlap is low, it is considered that the assembly consistency of each diode is excessive. When under the same current signal, the larger the forward voltage drop of the diode, the worse the contact effect between the diode and the insulating heat sink 12, and re-installation and maintenance are required.

[0057] Optional, continue to refer to Figure 3 and Figure 4 The assembly consistency detection circuit 103 of the DC / DC converter also includes a current sensor 110; a first end of the current sensor 110 is electrically connected to the positive electrode of the DC current source 105, a second end of the current sensor 110 is electrically connected to the positive electrode of the DC voltage source 104 and the power tube 102 respectively, and a third end of the current sensor 110 is connected to the oscilloscope 107; the current sensor 110 is used to collect a fixed current signal in real time and output it to the power tube 102 and the oscilloscope 107.

[0058] When detecting each MOS tube in the DC / DC converter 100, the first end of the current sensor 110 is electrically connected to the positive electrode of the DC current source 105, the second end of the current sensor 110 is electrically connected to the positive electrode of the DC voltage source 104 and the drain of the MOS tube respectively, and the third end of the current sensor 110 is connected to the oscilloscope 107; the current sensor 110 is used to collect the fixed current signal output by the DC current source 105 in real time, and output it to the MOS tube, so that the MOS is turned on, and then the MOS tubes in each boost circuit 101 are connected to the same circuit, the temperature of the MOS tube will rise rapidly, and then the forward voltage drop of the MOS tube will change accordingly, and at the same time, the oscilloscope 107 can receive the fixed current signal and collect the voltage drop at both ends of the MOS tube, so as to facilitate the subsequent comparison of the overlap of the forward voltage drop curves of each MOS tube to determine the assembly consistency of each MOS tube.

[0059] When detecting each diode in the DC / DC converter 100, the first end of the current sensor 110 is electrically connected to the positive electrode of the DC current source 105, the second end of the current sensor 110 is electrically connected to the positive electrode of the DC voltage source 104 and the anode of the diode tube respectively, and the third end of the current sensor 110 is connected to the oscilloscope 107; the current sensor 110 is used to collect the fixed current signal output by the DC current source 105 in real time, and output it to the diode, so that the diode is turned on, and then the diodes in each boost circuit 101 are connected to the same circuit. The temperature of the diode will rise rapidly, and the forward voltage drop of the diode will change accordingly. At the same time, the oscilloscope 107 can receive the fixed current signal and collect the voltage drop at both ends of the diode, so as to facilitate the subsequent comparison of the overlap of the forward voltage drop curves of each diode to determine the assembly consistency of each diode.

[0060] Optional, continue to refer to Figure 3 and Figure 4 The DC / DC converter assembly consistency detection circuit 103 further includes a first resistor R1 , which is arranged between the positive electrode of the DC voltage source 104 and the positive electrode of the DC current source 105 .

[0061] Among them, by setting a first resistor R1 between the positive pole of the DC voltage source 104 and the DC current source 105, the resistance value of the first resistor R1 can be selected to be 1KΩ, and the first resistor R1 plays a voltage divider role. The first resistor R1 adjusts the voltage output by the DC voltage source 104 so that the voltage output by the first resistor R1 meets the required working voltage and meets the detection requirements.

[0062] Figure 6 A schematic diagram of a DC / DC converter assembly consistency detection device provided by an embodiment of the present invention is shown in FIG. Figure 6 As shown, the DC / DC converter assembly consistency detection device 200 includes the DC / DC converter assembly consistency detection circuit 103 according to any one of the above embodiments.

[0063] It should be noted that, since the DC / DC converter 100 assembly consistency detection device provided in this embodiment includes the assembly consistency detection circuit 103 of the DC / DC converter as described in any embodiment of the present invention, it has the same or corresponding beneficial effects as the DC / DC converter assembly consistency detection circuit 103, which will not be elaborated here.

[0064] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A DC / DC converter assembly consistency detection circuit, characterized in that: The DC / DC converter includes at least two boost circuits arranged in parallel, and the boost circuit includes a power tube; The assembly consistency detection circuit of the DC / DC converter comprises at least a DC voltage source, a DC current source and a processing unit; The DC voltage source and the DC current source are respectively connected in parallel with each of the power tubes; The DC voltage source is used to provide a fixed voltage signal for each of the power tubes; The DC current source is used to provide a fixed current signal for each of the power tubes; The power tube outputs a detection signal according to the fixed voltage signal and the fixed current signal; The processing unit is used to obtain the detection signal output by each of the power tubes, and detect the assembly consistency between the power tubes according to each of the detection signals and the fixed current signal.

2. The assembly consistency detection circuit of the DC / DC converter according to claim 1, characterized in that: The processing unit is further used to obtain a forward voltage drop curve of each of the power tubes according to each of the detection signals and the fixed current signal, and to determine assembly consistency between the power tubes according to each of the forward voltage drop curves.

3. The assembly consistency detection circuit of the DC / DC converter according to claim 1, characterized in that: The assembly consistency detection circuit of the DC / DC converter includes an oscilloscope, a voltage collection end of the oscilloscope is electrically connected to each of the power tubes, a current collection end of the oscilloscope is electrically connected to the positive electrode of the DC current source, and an output end of the oscilloscope is electrically connected to the processing unit; The oscilloscope is used to collect the detection signal of the power tube and the fixed current signal output by the DC current source, and output them to the processing unit.

4. The DC / DC converter assembly consistency detection circuit according to claim 3, characterized in that: The oscilloscope includes a trigger unit, which is electrically connected to the DC current source. The trigger unit is used to collect a fixed current signal at the output end of the DC current source, and when the fixed current signal is greater than a preset trigger current signal, collect a detection signal of the power tube and a current signal output by the DC current source.

5. The assembly consistency detection circuit of the DC / DC converter according to claim 3, characterized in that: The assembly consistency detection circuit of the DC / DC converter further comprises an oscilloscope voltage acquisition unit, a receiving end of the oscilloscope voltage acquisition unit is electrically connected to each of the power tubes respectively, and an output end of the oscilloscope voltage acquisition unit and a positive electrode of the DC current source are both connected to the oscilloscope; The oscillographic voltage acquisition unit is used to collect the detection signal of each power tube.

6. The DC / DC converter assembly consistency detection circuit according to claim 1, characterized in that: The power tube includes a MOS tube; The drain of the MOS tube is electrically connected to the positive electrode of the DC current source and the positive electrode of the DC voltage source, and the source of the MOS tube is electrically connected to the negative electrode of the DC current source and the negative electrode of the DC voltage source; The processing unit is used to obtain the detection signal output by each of the MOS tubes, and detect the assembly consistency between the MOS tubes according to each of the detection signals and the fixed current signal.

7. The DC / DC converter assembly consistency detection circuit according to claim 1, characterized in that: The power tube includes a diode; The anode of the diode is electrically connected to the positive electrode of the DC current source and the positive electrode of the DC voltage source, and the cathode of the diode is electrically connected to the negative electrode of the DC current source and the negative electrode of the DC voltage source; The processing unit is used to obtain the detection signal output by each of the diodes, and detect the assembly consistency between the diodes according to each of the detection signals and the fixed current signal.

8. The DC / DC converter assembly consistency detection circuit according to claim 3, characterized in that: The assembly consistency detection circuit of the DC / DC converter also includes a current sensor; The first end of the current sensor is electrically connected to the positive electrode of the DC current source, the second end of the current sensor is electrically connected to the positive electrode of the DC voltage source and the power tube respectively, and the third end of the current sensor is connected to the oscilloscope; The current sensor is used to collect a fixed current signal in real time and output it to the power tube and the oscilloscope.

9. The assembly consistency detection circuit of the DC / DC converter according to claim 1, characterized in that: The assembly consistency detection circuit of the DC / DC converter further includes a first resistor, which is arranged between the positive electrode of the DC voltage source and the positive electrode of the DC current source.

10. A DC / DC converter assembly consistency detection device, characterized in that: An assembly consistency detection circuit for a DC / DC converter comprising any one of claims 1-9.

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