Pulse forming circuit and LTD module

Abstract

According to the improved pulse forming circuit and LTD module design, Brick branches are connected in parallel during charging, and high voltage and high current cannot be generated in the circuit; and during discharging, each Bick branch independently discharges and does not interfere with each other. The LTD module comprises N Brick branches, each Brick branch is in coupling connection with a secondary load through a magnetic core of the LTD module, the Brick branches are connected in parallel at a power supply end, and each secondary coil is connected in series with the load.

Description

Technical Field

[0001] The present application relates to the technical field of electronic circuits, and in particular to a pulse forming circuit and an LTD module. Background Art

[0002] The solid-state linear transformer driver (LTD) is one of the new pulse power circuit methods. The basic unit of a typical LTD driver source is an LTD module. Each LTD module consists of multiple Brick branches and switches S. After multiple Brick branches are connected in parallel, energy is transmitted to the secondary load through magnetic core coupling. Figure 1 The circuit connection schematic diagram of the Brick connection in the LTD module is described. After the capacitor in the Brick branch in the module is charged, when the Brick branch switch is turned on, the electric pulse generated by the parallel Brick branch is transmitted to the load through the magnetic core coupling (equivalent to a 1:1 transformer). However, this design affects the output front edge of the LED module due to the jitter of the switch on time and the difference between switches. In addition, the primary coil of this design needs to pass a large current, which will cause the coil temperature to rise rapidly. Excessive temperature may cause the insulation material of the coil to fail, causing the coil to burn out. At the same time, when the current is too large, it may cause the inductor to saturate.

[0003] A new design scheme is proposed in patent CN215378883U, such as Figure 2 As described above, by changing the connection mode of the Brick branch circuit inside the LTD module, a self-synchronous connection mode is adopted to make all Brick branches discharge to the secondary load at the same time, thereby eliminating the influence of the dispersion of the conduction time of multiple switches on the output front edge of the LTD module. This improved design adopts the form of Brick branches connected in series, resulting in a very high voltage in the Brick branch section during discharge, and the requirements for electrical components such as switches and capacitors on the Brick branches are very high. In actual use, excessive voltage often breaks down components in the circuit, and the life of the circuit is short. In addition, since all Brick branches are connected in series, when one of the components fails, the entire module will fail, and it is also difficult to find the fault location during maintenance. Summary of the invention

[0004] In view of this, the purpose of the present application is to provide a pulse forming circuit and an LTD module to improve the above-mentioned design problems.

[0005] In order to solve the above technical problems, the embodiments of the present application are implemented in the following ways:

[0006] A pulse forming circuit and an LTD module, the LTD module includes N brick branches, each brick branch is coupled to a secondary load through an LTD module magnetic core, each brick branch is connected in parallel at a power supply end, and each secondary coil is connected in series with a load. Each brick branch includes at least a switch, a diode, and a capacitor.

[0007] In some embodiments, the LTD module magnetic core is a ring-shaped magnetic core, which may be a circular ring or a square ring.

[0008] In some implementations, the switch may be a gas switch, an insulated gate bipolar transistor (IGBT) switch, a MOSFET switch, etc., preferably a MOSFET switch control is adopted.

[0009] In some embodiments, the ratio of the primary coil to the secondary coil of the LTD core is 1:1-5.

[0010] In some embodiments, each primary coil of the LTD core is connected to the discharge diode D i Connect in parallel.

[0011] In some embodiments, the pulse forming circuit mainly includes a DC power supply, a charging switch Q0, a charging diode D0, N capacitors C i , N discharge switches Q i , N discharge diodes D i and N LTD cores, i=1,2,3...,N; the circuit structure is as follows:

[0012] The positive electrode of the DC power supply is connected to the anode of the charging diode D0, and the cathode of the charging diode D0 is connected to the capacitor C i The positive terminal of capacitor C i The cathode of the discharge diode D i The positive pole is connected to the primary coil of the LTD core.

[0013] In some embodiments, the pulse signal in the pulse forming circuit is transmitted to the MOSFET switch via an optical cable.

[0014] On the other hand, this application also proposes an LTD module and a circuit thereof, which are implemented using the circuit described in this application.

[0015] This application has the following advantages and beneficial effects:

[0016] 1. In the pulse forming circuit and LTD module of the present application, each Brick branch is connected in parallel, and high voltage and high current will not be generated in the circuit, and the requirements for components in the circuit are low.

[0017] 2. The pulse forming circuit and LTD module of the present application have high overall safety.

[0018] 3. When the pulse forming circuit and LTD module of the present application discharge, each Brick branch discharges independently without interfering with each other. When a single module fails, it does not affect the operation of the entire circuit, and the faulty circuit can be quickly identified and repaired. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 This is a schematic diagram of the circuit principle of the traditional LTD module's internal Brick parallel output structure;

[0021] Figure 2 This is a schematic diagram of the internal self-synchronization circuit principle of the LTD module in the CN215378883U patent;

[0022] Figure 3 This is a schematic diagram of the pulse forming circuit and LTD module circuit principle of this application;

[0023] Figure 4 This is a LTD charging diagram for this application;

[0024] Figure 5 This is the LTD discharge schematic diagram for this application. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions 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 part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0028] In the description of the present invention, it should be noted that if the terms "upper", "lower", "inside", "outside", etc. appear to indicate an orientation or position relationship, they are based on the orientation or position relationship shown in the accompanying drawings, or are the orientation or position relationship in which the product of the invention is usually placed when used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0029] In addition, the terms “first”, “second”, etc., if used, are merely used to distinguish between the descriptions and should not be understood as indicating or implying relative importance.

[0030] It should be noted that, in the absence of conflict, the features in the embodiments of the present invention may be combined with each other.

[0031] Example 1

[0032] Compared with the traditional typical LTD module, this embodiment proposes an improved LTD module internal branch charging / discharging synchronization circuit. The circuit of this embodiment adopts Figure 3 The LTD module includes N Brick branches, each Brick branch is coupled to the secondary load through the LTD module core, each Brick branch is connected in parallel at the power supply end, and each secondary coil is connected in series with the load. Each Brick branch includes at least a switch, a diode and a capacitor.

[0033] In this embodiment, the number of Brick branches may be 5 to 100.

[0034] The LTD module magnetic core in this embodiment is a ring-shaped magnetic core.

[0035] In this embodiment, the Brick branch is wound around the magnetic core of each LTD module, with a total of 1 turn, the secondary coil is m turns, 1≤m≤5, and the ratio of the internal voltage of the LTD module to the secondary output voltage is 1:m.

[0036] Example 2

[0037] like Figure 4 As shown, when the LTD circuit is charged, each Brick branch is connected in parallel with the power supply, switch Q0 is turned on, and switches Q1~Q N Disconnect, and the DC power supply is supplied to each branch capacitor C1~C N The DC power supply voltage is U0, the branch voltage is also U0, and the charging switch is controlled by Q0 to ensure the consistency of charging.

[0038] Example 3

[0039] As shown in Question 5, when the LTD circuit is discharged, switch Q0 is disconnected and switches Q1 to Q N When the capacitor is turned on, each Brick branch discharges independently, and at the same time, the energy stored on the capacitor is transferred to the high-voltage output port (load end) after electromagnetic coupling isolation, and a superimposed voltage is output. During discharge, each Brick branch is independent of each other. For example, Q1, C1, and the magnetic induction coil form a discharge loop. At the secondary coil end (B end), the induced voltage is connected in series to obtain a superimposed voltage. When the voltage of a single Brick branch is U, the primary coil: secondary coil is 1:2, then the load voltage U can be obtained. mix =U×2×N. The load end is usually the output electrode pin, without other electrical components. Compared with the existing design, the voltage and current of the A end are both low voltage and current, and no special requirements are required for the electrical components used, which greatly improves the safety of the equipment.

[0040] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A pulse forming circuit and an LTD module, characterized in that: The LTD module includes N Brick branches, each Brick branch is coupled to a secondary load through an LTD module magnetic core, each Brick branch is connected in parallel at the power supply end, and each secondary coil is connected in series with the load.

2. The pulse forming circuit and LTD module according to claim 1, characterized in that: The Brick branch includes a switch, a diode and a capacitor.

3. The pulse forming circuit and LTD module according to claim 1, characterized in that: The LTD module magnetic core is a ring-shaped magnetic core.

4. The pulse forming circuit and LTD module according to claim 1, characterized in that: The switch is a MOSFET switch.

5. The pulse forming circuit and LTD module according to claim 1, characterized in that: The ratio of the primary coil to the secondary coil of the LTD core is 1:1 to 5.

6. The pulse forming circuit and LTD module according to claim 1, characterized in that: Each primary coil of the LTD core and the discharge diode D i Connect in parallel.

7. The pulse forming circuit and LTD module according to claim 1, characterized in that: The pulse forming circuit mainly includes a DC power supply, a charging switch Q0, a charging diode D0, and N capacitors C i , N discharge switches Q i , N discharge diodes D i and N LTD cores, i=1,2,3...,N; the circuit structure is as follows: The positive electrode of the DC power supply is connected to the anode of the charging diode D0, and the cathode of the charging diode D0 is connected to the capacitor C i The positive terminal of capacitor C i The cathode of the discharge diode D i The positive pole is connected to the primary coil of the LTD core.

8. The pulse forming circuit and LTD module according to claim 1, characterized in that: The pulse signal in the pulse forming circuit is transmitted to the MOSFET switch through the optical cable.

9. An LTD module and its circuit, characterized in that: The method is implemented by using a circuit as described in any one of claims 1 to 8.

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