Oil-cooled 10kV rectification unit structure

Abstract

The oil-cooled 10kV rectification unit structure comprises a rectification unit and a heat dissipation device, the rectification unit is composed of a rectification bridge arm, and the rectification bridge arm is formed by connecting a plurality of rectification diodes in series; the heat dissipation device is composed of an oil inlet pipe, an oil return pipe and a plurality of liquid cooling radiators. Liquid inlets of the liquid cooling radiators are communicated with the oil inlet pipe or liquid outlets of the corresponding liquid cooling radiators through insulating branch pipes. The device is characterized in that the rectifier diode is located between the two adjacent liquid cooling radiators, and the two side faces of the rectifier diode make contact with the heat absorption faces of the two adjacent liquid cooling radiators. According to the oil-cooled 10kV rectification unit structure, the two liquid-cooled radiators realize double-sided heat dissipation of the rectification diode, the heat dissipation efficiency is higher, the working temperature of the rectification diode can be effectively controlled within a reasonable range, the rectification diode is prevented from losing efficacy due to overhigh temperature, and the stable work of a high-voltage frequency converter is ensured.

Description

Technical Field

[0001] The utility model relates to an oil-cooled 10kV rectifier unit structure, and more specifically, to an oil-cooled 10kV rectifier unit structure. Background Art

[0002] The high-voltage inverter consists of a rectifier part and an inverter part. The rectifier part converts the input three-phase AC power into DC power and inputs it to the DC bus. The input end of the inverter part is connected to the DC bus, and the DC power on the DC bus is converted into a frequency-controllable AC power output to drive the motor to perform controllable frequency conversion. During the operation of the high-voltage inverter, the rectifier diodes in the rectifier part and the power devices (such as IGBT) in the inverter part will generate a lot of heat. If the heat generated by the rectifier diodes and power devices cannot be dissipated in time, the temperature of the rectifier diodes and power devices will rise, affecting the normal operation of the inverter. In severe cases, it will also cause damage to the inverter. Therefore, existing high-voltage inverters are equipped with heat dissipation devices to dissipate heat from the devices.

[0003] At present, existing high-voltage inverters usually use air cooling or water cooling. Air cooling is easy to bring in dust from the external environment and cannot be used in places where dust pollution is relatively serious. Water cooling also has its defects. Deionized cooling water is required for cooling. Because there are many pipe interfaces, there is a risk of water leakage. Because of the dust in the air and on the surface of objects, the leaked deionized water quickly becomes conductive water, which may cause a short circuit and cause serious accidents.

[0004] In the process of cooling the rectifier diodes in the rectifier part, the heat dissipation device in the existing high-voltage inverter fixes the rectifier diodes on a water-cooled heat sink and takes away the heat generated by the rectifier diodes during operation by direct contact between the rectifier DC tube and the water-cooled heat sink. However, this heat dissipation method uses a single-sided contact method to dissipate heat. When the rectification power of the rectifier diode is relatively large, the heat dissipation effect is poor, which will cause the temperature of the rectifier diode to be too high. In severe cases, the rectifier diode will be damaged, affecting the normal operation of the high-voltage inverter. Summary of the invention

[0005] In order to overcome the disadvantages of the above technical problems, the utility model provides an oil-cooled 10kV rectifier unit structure.

[0006] The utility model discloses an oil-cooled 10kV rectifier unit structure, comprising a rectifier unit and a heat sink, wherein the input end of the rectifier unit is connected to a three-phase AC power supply, the rectifier unit is composed of a rectifier bridge arm, and the rectifier bridge arm is composed of a plurality of rectifier diodes connected in series; the heat sink is composed of an oil inlet pipe, an oil return pipe and a plurality of liquid-cooled radiators, the liquid inlet of the liquid-cooled radiator is connected to the oil inlet pipe or the liquid outlet of the corresponding liquid-cooled radiator through an insulating branch pipe, and the liquid outlet of the liquid-cooled radiator is connected to the oil return pipe or the liquid inlet of the corresponding liquid-cooled radiator through an insulating branch pipe; the utility model is characterized in that: the rectifier diode is located between two adjacent liquid-cooled radiators, and the two side surfaces of the rectifier diode are in contact with the heat absorption surfaces of the two adjacent liquid-cooled radiators.

[0007] The utility model discloses an oil-cooled 10kV rectifier unit structure, wherein the number of rectifier bridge arms is 6, and each rectifier bridge arm is composed of 4 rectifier diodes connected in series; 6 heat dissipation units are arranged in the heat dissipation device, and one heat dissipation unit dissipates heat for 4 rectifier diodes in one rectifier bridge arm, and each heat dissipation unit is composed of 5 liquid-cooled radiators arranged at intervals, and 4 rectifier diodes in one rectifier bridge arm are clamped between the 5 liquid-cooled radiators in one heat dissipation unit.

[0008] The utility model discloses an oil-cooled 10kV rectifier unit structure, wherein both ends of each heat dissipation unit are provided with a left baffle and a right baffle, the left baffle and the right baffle are connected via three tie rods, and the left baffle and the right baffle clamp five liquid-cooled radiators therebetween.

[0009] The utility model discloses an oil-cooled 10kV rectifier unit structure, wherein the cooling medium flowing through the oil inlet pipe, the oil return pipe and the liquid cooling radiator of the heat dissipation device is insulating oil or fluorocarbon coolant.

[0010] The utility model discloses an oil-cooled 10kV rectifier unit structure, wherein each rectifier diode in the rectifier unit is connected in parallel with a voltage-equalizing resistor.

[0011] The beneficial effects of the utility model are as follows: the oil-cooled 10kV rectifier unit structure of the utility model comprises a rectifier unit and a heat dissipation device, the rectifier power supply is composed of a rectifier bridge arm formed by a plurality of rectifier diodes connected in series, thereby realizing the rectification of the input three-phase AC power supply; the heat dissipation device is composed of an oil inlet pipe, an oil return pipe and a plurality of hot and cold radiators, and the rectifier diode is arranged between two adjacent liquid-cooled radiators, so that during the operation of the high-voltage frequency converter, the heat generated by the rectifier diode will be taken away by the two liquid-cooled radiators on both sides thereof, thus realizing "double-sided heat dissipation" of the rectifier diode. Compared with the existing single-sided heat dissipation of the rectifier diode, the heat dissipation efficiency is higher, and the operating temperature of the rectifier diode can be effectively controlled within a reasonable range, thereby preventing the rectifier diode from failing due to excessively high temperature, and ensuring the stable operation of the high-voltage frequency converter.

[0012] Furthermore, the oil inlet pipe, oil return pipe and liquid cooling radiator of the heat dissipation device in the utility model use insulating oil or fluorocarbon coolant. Compared with the existing air cooling and water cooling, it is not only suitable for harsh environments with a lot of dust, but also can avoid the phenomenon of conductive short circuit that is prone to occur in deionized water cooling, further ensuring the working stability of the high-voltage inverter. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a circuit diagram of the rectifier unit in the utility model;

[0014] Figure 2 This is a front view of the heat dissipation device in the utility model;

[0015] Figure 3 It is a top view of the heat dissipation device in the utility model;

[0016] Figure 4 It is a structural schematic diagram of the heat dissipation unit in the utility model.

[0017] In the figure: 1 rectifier unit, 2 three-phase AC power supply, 3 rectifier diode, 4 rectifier bridge arm, 5 heat sink, 6 oil inlet pipe, 7 oil return pipe, 8 liquid cooling radiator, 9 voltage equalizing resistor, 10 left baffle, 11 right baffle, 12 pull rod, 13 insulating branch pipe. DETAILED DESCRIPTION

[0018] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0019] The oil-cooled 10kV rectifier unit structure of the utility model is composed of a rectifier unit 1 and a heat sink 5. Figure 1 As shown, a circuit diagram of the rectifier unit in the utility model is given. Figure 2 and Figure 3 The front view and top view of the heat dissipation device in the utility model are given. The rectifier unit 1 shown is composed of a plurality of rectifier bridge arms 4, each of which is composed of a plurality of rectifier diodes 3 connected in series in sequence. The input end of the rectifier power supply 1 formed by the rectifier bridge arms 4 is connected to the three-phase AC power supply 2. The input three-phase AC power supply 2 is converted into direct current after being rectified by the rectifier power supply 1, and the direct current is converted into a controllable AC output power after being inverted by the inverter unit in the high-voltage inverter to control the operation of the AC motor.

[0020] The heat dissipation device 5 shown is composed of an oil inlet pipe 6, an oil return pipe 7 and a plurality of liquid cooling radiators 8, wherein cooling medium flows through the oil inlet pipe 6, the oil return pipe 7 and the liquid cooling radiator 8. The liquid inlet of the liquid cooling radiator 8 is connected to the liquid outlet of the oil inlet pipe 6 or the corresponding liquid cooling radiator 8 through an insulating branch pipe 13, and the liquid outlet of the liquid cooling radiator 8 is connected to the liquid inlet of the oil return pipe 7 or the corresponding liquid cooling radiator 8 through an insulating branch pipe 13. In this way, the cooling medium can take away the heat absorbed by the liquid cooling radiator 8 when it circulates in the oil inlet pipe 6, the liquid cooling radiator 8 and the oil return pipe 7 in sequence.

[0021] The rectifier diode 3 shown is located between two adjacent liquid-cooled radiators 8, that is, two liquid-cooled radiators 8 clamp one rectifier diode 3, so that the two sides of one rectifier diode 3 are in contact with the heat dissipation surfaces of the two liquid-cooled radiators 8 respectively. During the operation of the high-voltage inverter, the heat generated by the rectifier diode 3 during operation will be absorbed by the two liquid-cooled radiators 8 on both sides thereof, and then taken away through the circulation of the cooling medium. Since the two liquid-cooled radiators 8 dissipate heat for one rectifier diode 3, it can be said to be "double-sided heat absorption". Compared with the existing single-sided heat dissipation, the heat dissipation device 5 in the utility model has a higher heat dissipation efficiency for the rectifier diode 3, and it is easier to maintain the temperature of the rectifier diode 3 within a reasonable range, ensuring the stable operation of the high-voltage inverter.

[0022] Figure 1 The rectifier unit 1 in the figure is a three-phase full-bridge rectifier circuit, which includes 6 rectifier bridge arms 4, each rectifier bridge arm 4 is composed of 4 rectifier diodes 3 connected in sequence, and both ends of each rectifier diode 3 are connected in parallel with a voltage-equalizing resistor 9 to balance the voltage across each rectifier diode 3. The heat dissipation device 5 shown in the figure is provided with 6 heat dissipation units, such as Figure 4 As shown, a schematic diagram of the structure of the heat dissipation unit in the utility model is given, and the six heat dissipation units dissipate heat for the rectifier diodes 3 in the six rectifier bridge arms 4 respectively.

[0023] As shown, each heat dissipation unit is provided with 5 liquid-cooled radiators 8, and the 5 liquid-cooled radiators 8 are arranged at intervals, that is, every two adjacent liquid-cooled radiators 8 are separated by a rectifier diode 3, which also realizes the layout structure in which two liquid-cooled radiators 8 dissipate heat for one rectifier diode 3. A left baffle 10 and a right baffle 11 are respectively provided at both ends of each heat dissipation unit, and the left baffle 10 and the right baffle 11 realize the clamping of the 5 liquid-cooled radiators 8 and the 4 rectifier diodes 3 therebetween. The left baffle 10 and the right baffle 11 shown are connected by three tie rods 12. In this way, under the pulling action of the tie rod 12 on the left baffle 10 and the right baffle 11, the 5 liquid-cooled radiators 8 and the 4 rectifier diodes 3 therebetween are pressed tightly, ensuring the close contact between the rectifier diode 3 and the liquid-cooled radiator 8.

[0024] The cooling medium flowing in the oil inlet pipe 6, the oil return pipe 7 and the liquid cooling radiator 8 of the heat dissipation device 5 is insulating oil or fluorocarbon coolant. Compared with the existing air cooling and water cooling, the cooling medium is not only suitable for harsh environments with more dust, but also can avoid the phenomenon of conductive short circuit that is easy to occur in deionized water cooling, thereby further ensuring the working stability of the high-voltage inverter.

Claims

1. An oil-cooled 10 kV rectifier unit structure, comprising a rectifier unit (1) and a heat sink (5), wherein the input end of the rectifier unit is connected to a three-phase AC power supply (2), the rectifier unit is composed of a rectifier bridge arm (4), and the rectifier bridge arm is composed of a plurality of rectifier diodes (3) connected in series; the heat sink is composed of an oil inlet pipe (6), an oil return pipe (7) and a plurality of liquid cooling radiators (8), the liquid inlet of the liquid cooling radiator is connected to the oil inlet pipe or the liquid outlet of the corresponding liquid cooling radiator through an insulating branch pipe (13), and the liquid outlet of the liquid cooling radiator is connected to the oil return pipe or the liquid inlet of the corresponding liquid cooling radiator through an insulating branch pipe; the characteristics are: The rectifier diode (3) is located between two adjacent liquid-cooled radiators (8), and two side surfaces of the rectifier diode are in contact with the heat absorbing surfaces of the two adjacent liquid-cooled radiators.

2. The oil-cooled 10kV rectifier unit structure according to claim 1 is characterized in that: The number of the rectifier bridge arms (4) is 6, and each rectifier bridge arm is composed of 4 rectifier diodes (3) connected in series; the heat dissipation device (5) is provided with 6 heat dissipation units, one heat dissipation unit dissipates heat for the 4 rectifier diodes in one rectifier bridge arm, and each heat dissipation unit is composed of 5 liquid-cooled heat sinks (8) arranged at intervals, and the 4 rectifier diodes in one rectifier bridge arm are clamped between the 5 liquid-cooled heat sinks in one heat dissipation unit.

3. The oil-cooled 10kV rectifier unit structure according to claim 2 is characterized in that: A left baffle (10) and a right baffle (11) are provided at both ends of each heat dissipation unit. The left baffle and the right baffle are connected via three tie rods (12). The left baffle and the right baffle clamp the five liquid cooling radiators (8) therebetween.

4. The oil-cooled 10kV rectifier unit structure according to claim 1 or 2, characterized in that: The cooling medium flowing through the oil inlet pipe (6), the oil return pipe (7) and the liquid cooling radiator (8) of the heat dissipation device (5) is insulating oil or fluorocarbon coolant.

5. The oil-cooled 10kV rectifier unit structure according to claim 1 or 2, characterized in that: Each rectifier diode (3) in the rectifier unit (1) is connected in parallel with a voltage-equalizing resistor (9).

Images