A motor controller controls a pre-charging circuit

Abstract

The utility model discloses a motor controller controlled pre-charging circuit, which belongs to the technical field of pre-charging circuit, including a pre-charging circuit and a pre-charging control circuit, wherein the pre-charging circuit is connected to the pre-charging control circuit; the pre-charging circuit includes a high-voltage battery, a switch KA1, a primary pre-charging relay KA2, a secondary pre-charging relay KA3, a pre-charging resistor R1, a pre-charging resistor R2 and a bus capacitor C, and the pre-charging control circuit includes a voltage regulator tube Z1, a battery end sampling resistor R3, a battery end sampling resistor R4, a capacitor segment sampling resistor R5, a capacitor segment sampling resistor R6 and an optocoupler relay O1. Through the above-mentioned method, the utility model adopts two-stage pre-charging, which reduces the instantaneous power borne by a single resistor, greatly improves the reliability of the resistor, and speeds up the charging time, solving the contradiction between reliability and rapid response under the existing charging method; although the utility model adds a relay, it is all processed in the internal circuit, and the control logic of the overall distribution box is not increased.

Description

Technical Field

[0001] The utility model relates to the technical field of pre-charging circuits, in particular to a motor controller controlling a pre-charging circuit. Background Art

[0002] The motor controller pre-charging circuit is a circuit for charging the motor control bus capacitor. The existing motor controller pre-charging circuit consists of a pre-charging resistor and a relay. The resistor is connected in series with the relay, and the relay is normally open. When receiving the upper high voltage command, the relay closes and charges the bus capacitor through this resistor.

[0003] However, the pre-charge resistor is subjected to a great impact current at the instant of charging. As the application fields of motor controllers increase and the power of motor controllers increases, the bus capacitance becomes larger and larger, and the pre-charge resistor that matches it also becomes larger and larger. The larger the capacitance, the longer the charging time. In order to shorten the charging time, the resistance has to be reduced. However, the consequence of reducing the resistance is that the instantaneous power of the resistor increases greatly, and the reliability of the resistor is greatly reduced. Therefore, there is always a contradiction between charging time and reliability.

[0004] Based on this, the utility model designs a motor controller to control the pre-charging circuit to solve the above problems. Utility Model Content

[0005] In view of the above-mentioned shortcomings of the prior art, the utility model provides a motor controller to control a pre-charging circuit.

[0006] In order to achieve the above objectives, the present invention is implemented through the following technical solutions:

[0007] A motor controller controls a pre-charging circuit, comprising a pre-charging circuit and a pre-charging control circuit, wherein the pre-charging circuit is connected to the pre-charging control circuit;

[0008] The pre-charging circuit includes a high-voltage battery, a switch KA1, a primary pre-charging relay KA2, a secondary pre-charging relay KA3, a pre-charging resistor R1, a pre-charging resistor R2 and a bus capacitor C. The positive electrode of the high-voltage battery, the contact of the primary pre-charging relay KA2, the contact of the secondary pre-charging relay KA3, the pre-charging resistor R1, the pre-charging resistor R2, the bus capacitor C, and the negative electrode of the high-voltage battery are sequentially connected in series to form a closed circuit;

[0009] The pre-charge control circuit includes a voltage regulator tube Z1, a battery end sampling resistor R3, a battery end sampling resistor R4, a capacitor segment sampling resistor R5, a capacitor segment sampling resistor R6 and an isolation optical coupler O1.

[0010] Furthermore, one end of the bus capacitor C is connected to the negative electrode of the high-voltage battery, and the other end of the bus capacitor C is connected to the positive electrode of the high-voltage battery through the switch KA1.

[0011] Furthermore, the contact of the first-level pre-charging relay KA2, the pre-charging resistor R1, and the pre-charging resistor R2 are connected in series in sequence, and the contact of the first-level pre-charging relay KA2, the pre-charging resistor R1, and the pre-charging resistor R2 are connected in parallel at both ends of the switch KA1.

[0012] Furthermore, the contacts of the secondary pre-charging relay KA3 are connected in parallel to both ends of the pre-charging resistor R1.

[0013] Furthermore, the contacts of the first-level pre-charging relay KA2, the battery-end sampling resistor R3 and the battery-end sampling resistor R4 are connected in series in sequence, and the contacts of the first-level pre-charging relay KA2, the battery-end sampling resistor R3 and the battery-end sampling resistor R4 are connected in parallel at both ends of the high-voltage battery.

[0014] Furthermore, the capacitor segment sampling resistor R5 and the capacitor segment sampling resistor R6 are connected, and the capacitor segment sampling resistor R5 and the capacitor segment sampling resistor R6 are connected in parallel at both ends of the bus capacitor C.

[0015] Furthermore, the capacitor section sampling resistor R5, the voltage regulator tube Z1, the optical coupler relay O1, and the battery end sampling resistor R4 are connected in series in sequence.

[0016] Furthermore, the optocoupler relay 01 includes a light emitting diode and an optocoupler secondary transistor.

[0017] Furthermore, the capacitor segment sampling resistor R5, the voltage regulator tube Z1, the light emitting diode, and the battery end sampling resistor R4 are connected in series in sequence.

[0018] Furthermore, the collector of the secondary transistor of the optocoupler is connected to a 24V power supply via the coil of the secondary pre-charge relay KA3, and the emitter of the secondary transistor of the optocoupler is grounded.

[0019] Compared with the prior art, the utility model has the following beneficial effects:

[0020] When the main control end issues a high voltage command, the controller controls the contact of the first-level pre-charging relay KA2 to close, and the high-voltage battery charges the bus capacitor C through the pre-charging resistor R1 and the pre-charging resistor R2 in series. When the bus capacitor is charged to the preset voltage, the contact of the second-level pre-charging relay KA3 is closed, and the high-voltage battery only charges the capacitor through the pre-charging resistor R2;

[0021] In the first stage of charging, the charging resistor is composed of a pre-charging resistor R1 and a pre-charging resistor R2 connected in series. The charging resistance is large, the charging current is small, and the loss on the resistor is also small. In the second stage of charging, the charging resistor is only the pre-charging resistor R2, which reduces the charging resistance. At the same time, during the second stage of charging, the voltage on the capacitor has reached a higher value. Although the charging resistance becomes smaller, the instantaneous power is still relatively small. Therefore, the present invention realizes the two functions of reducing the charging time and improving the reliability of the resistor, and solves the contradiction between reliability and fast response under the existing charging method. Although the present invention adds a relay, it is all processed in the internal circuit and does not increase the control logic of the overall distribution box. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 The utility model is a circuit connection diagram of a motor controller controlling a pre-charging circuit. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0025] Embodiment 1

[0026] In some embodiments, please refer to the attached instructions. Figure 1 , a motor controller controls a pre-charging circuit, including a pre-charging circuit and a pre-charging control circuit, the pre-charging circuit being connected to the pre-charging control circuit;

[0027] The pre-charging circuit includes a high-voltage battery, a switch KA1, a primary pre-charging relay KA2, a secondary pre-charging relay KA3, a pre-charging resistor R1, a pre-charging resistor R2 and a bus capacitor C;

[0028] The primary pre-charging relay KA2 and the secondary pre-charging relay KA3 both include contacts and control coils;

[0029] The positive electrode of the high-voltage battery, the contact of the first-level pre-charging relay KA2, the contact of the second-level pre-charging relay KA3, the pre-charging resistor R1, the pre-charging resistor R2, the bus capacitor C, and the negative electrode of the high-voltage battery are connected in series in sequence to form a closed circuit;

[0030] The control end of the switch KA1 and the control coil of the primary pre-charging relay KA2 are both connected to a controller, and the controller controls the closing and opening of the contacts of the switch KA1 and the primary pre-charging relay KA2;

[0031] The pre-charge control circuit includes a voltage regulator tube Z1, a battery end sampling resistor R3, a battery end sampling resistor R4, a capacitor segment sampling resistor R5, a capacitor segment sampling resistor R6 and an optocoupler relay O1.

[0032] When the main control end issues a high voltage command, the controller controls the contact of the first-level pre-charging relay KA2 to close, and the high-voltage battery charges the bus capacitor C through the pre-charging resistor R1 and the pre-charging resistor R2 in series. When the bus capacitor is charged to the preset voltage, the contact of the second-level pre-charging relay KA3 is closed, and the high-voltage battery only charges the capacitor through the pre-charging resistor R2;

[0033] In the first stage of charging, the charging resistor is composed of a pre-charging resistor R1 and a pre-charging resistor R2 connected in series. The charging resistance is large, the charging current is small, and the loss on the resistor is also small. In the second stage of charging, the charging resistor is only the pre-charging resistor R2, which reduces the charging resistance. At the same time, during the second stage of charging, the voltage on the capacitor has reached a higher value. Although the charging resistance becomes smaller, the instantaneous power is still relatively small. Therefore, the utility model realizes the two functions of reducing the charging time and improving the reliability of the resistor.

[0034] One end of the bus capacitor C is connected to the negative electrode of the high-voltage battery, and the other end of the bus capacitor C is connected to the positive electrode of the high-voltage battery through the switch KA1.

[0035] The contact of the first-level pre-charging relay KA2, the pre-charging resistor R1, and the pre-charging resistor R2 are connected in series in sequence, and the contact of the first-level pre-charging relay KA2, the pre-charging resistor R1, and the pre-charging resistor R2 are connected in parallel at both ends of the switch KA1.

[0036] The contacts of the secondary pre-charging relay KA3 are connected in parallel to the two ends of the pre-charging resistor R1.

[0037] The contacts of the first-level pre-charging relay KA2, the battery-end sampling resistor R3 and the battery-end sampling resistor R4 are connected in series in sequence, and the contacts of the first-level pre-charging relay KA2, the battery-end sampling resistor R3 and the battery-end sampling resistor R4 are connected in parallel at both ends of the high-voltage battery.

[0038] The capacitor segment sampling resistor R5 and the capacitor segment sampling resistor R6 are connected, and the capacitor segment sampling resistor R5 and the capacitor segment sampling resistor R6 are connected in parallel at both ends of the bus capacitor C.

[0039] The capacitor section sampling resistor R5, the voltage regulator tube Z1, the optical coupler relay O1, and the battery end sampling resistor R4 are connected in series in sequence.

[0040] The photocoupler relay 01 includes a light emitting diode and a photocoupler secondary transistor.

[0041] The capacitor section sampling resistor R5, the voltage regulator tube Z1, the light emitting diode, and the battery end sampling resistor R4 are connected in series in sequence.

[0042] The collector of the secondary transistor of the optocoupler is connected to a 24V power supply through the coil of the secondary pre-charge relay KA3, and the emitter of the secondary transistor of the optocoupler is grounded.

[0043] The light emitting diode is used to radiate light to the secondary transistor of the optocoupler to control the conduction or cutoff of the secondary transistor of the optocoupler;

[0044] When the voltage of Vr6 is higher than the voltage at Vr4, the voltage regulator Z1 will be turned on, the optocoupler relay 01 will be turned on, and the current will flow from the capacitor segment sampling resistor R5, the voltage regulator Z1, and the light-emitting diode to the battery end sampling resistor R4, and the light-emitting diode will emit light;

[0045] When the light-emitting diode emits light, the light emitted shines on the secondary transistor of the optocoupler on the opposite side, and the secondary transistor of the optocoupler is turned on, attracting the coil of the secondary pre-charge relay KA3, and the contacts of the secondary pre-charge relay KA3 are closed;

[0046] When the light-emitting diode does not emit light, since the secondary transistor of the optocoupler is no longer irradiated by light, the secondary transistor of the optocoupler does not conduct, and the contacts of the secondary pre-charge relay KA3 are disconnected.

[0047] Embodiment 2

[0048] In some embodiments, Figure 1 As shown, as a preferred embodiment of the utility model, assuming that the high-voltage battery voltage is Up, the voltage at the bus capacitor C is Uc, and it is required to charge Uc to one third of Up, start the second-stage pre-charging, that is, the contacts of the secondary pre-charging relay KA3 are closed, and charging is only carried out through the pre-charging resistor R2.

[0049] Assuming that the voltage division ratio of Ur4 at Vr4 is Ar4, and the voltage division ratio of Ur6 at Vr6 is Ar6, then:

[0050]

[0051] Then we have:

[0052]

[0053] Then we have:

[0054]

[0055]

[0056] Because Up and Uc are high voltages, the battery-end sampling resistor R4 and the capacitor-segment sampling resistor R6 are set to smaller resistance values ​​to obtain a lower voltage on Ur4 and Ur6. Therefore, the battery-end sampling resistor R3 is much larger than the battery-end sampling resistor R4, and the capacitor-segment sampling resistor R5 is much larger than the capacitor-segment sampling resistor R6.

[0057] In the numerators of Ar4 and Ar6 calculation formulas, the battery end sampling resistor R4 and the capacitor segment sampling resistor R6 can be ignored. We only need to take:

[0058] The calculation here ignores the voltage drop of the optocoupler and the working voltage of the voltage regulator. The actual calculation needs to take into account that the actual values ​​of the capacitor-end sampling resistor R6 and the battery-end sampling resistor R4 will be slightly different from those here.

[0059] In this way, when Uc is charged to one-third Up, the contacts of the secondary pre-charging relay KA3 can be closed, and the second-stage charging is completed by the pre-charging resistor R2. The small charging resistance in the second stage can reduce the charging time. Therefore, the utility model realizes the two functions of reducing the charging time and improving the reliability of the resistor.

[0060] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A motor controller controls a pre-charging circuit, characterized in that: It includes a precharge circuit and a precharge control circuit, and the precharge circuit is connected to the precharge control circuit; The pre-charging circuit includes a high-voltage battery, a switch KA1, a primary pre-charging relay KA2, a secondary pre-charging relay KA3, a pre-charging resistor R1, a pre-charging resistor R2 and a bus capacitor C. The positive electrode of the high-voltage battery, the contact of the primary pre-charging relay KA2, the contact of the secondary pre-charging relay KA3, the pre-charging resistor R1, the pre-charging resistor R2, the bus capacitor C and the negative electrode of the high-voltage battery are sequentially connected in series to form a closed circuit; The pre-charge control circuit includes a voltage regulator tube Z1, a battery end sampling resistor R3, a battery end sampling resistor R4, a capacitor segment sampling resistor R5, a capacitor segment sampling resistor R6 and an isolation optical coupler O1.

2. Motor controller according to claim 1 controls pre-charge circuit, it is characterized in that, One end of the bus capacitor C is connected to the negative electrode of the high-voltage battery, and the other end of the bus capacitor C is connected to the positive electrode of the high-voltage battery through the switch KA1.

3. motor controller according to claim 2 controls pre-charge circuit, it is characterized in that, The contact of the first-level pre-charging relay KA2, the pre-charging resistor R1, and the pre-charging resistor R2 are connected in series in sequence, and the contact of the first-level pre-charging relay KA2, the pre-charging resistor R1, and the pre-charging resistor R2 are connected in parallel at both ends of the switch KA1.

4. motor controller according to claim 3 controls pre-charge circuit, it is characterized in that, The contacts of the secondary pre-charging relay KA3 are connected in parallel to the two ends of the pre-charging resistor R1.

5. motor controller according to claim 4 controls pre-charge circuit, it is characterized in that, The contacts of the first-level pre-charging relay KA2, the battery-end sampling resistor R3 and the battery-end sampling resistor R4 are connected in series in sequence, and the contacts of the first-level pre-charging relay KA2, the battery-end sampling resistor R3 and the battery-end sampling resistor R4 are connected in parallel at both ends of the high-voltage battery.

6. Motor controller according to claim 5 controls pre-charge circuit, it is characterized in that, The capacitor segment sampling resistor R5 and the capacitor segment sampling resistor R6 are connected, and the capacitor segment sampling resistor R5 and the capacitor segment sampling resistor R6 are connected in parallel at both ends of the bus capacitor C.

7. Motor controller according to claim 6 controls pre-charge circuit, it is characterized in that, The capacitor section sampling resistor R5, the voltage regulator tube Z1, the optical coupler relay O1, and the battery end sampling resistor R4 are connected in series in sequence.

8. Motor controller according to claim 7 controls pre-charge circuit, it is characterized in that, The photocoupler relay 01 includes a light emitting diode and a photocoupler secondary transistor.

9. Motor controller according to claim 8 controls pre-charge circuit, it is characterized in that, The capacitor section sampling resistor R5, the voltage regulator tube Z1, the light emitting diode, and the battery end sampling resistor R4 are connected in series in sequence.

10. The motor controller according to claim 9 controls the pre-charge circuit, characterized in that, The collector of the secondary transistor of the optocoupler is connected to the power supply through the coil of the secondary pre-charge relay KA3, and the emitter of the secondary transistor of the optocoupler is grounded.

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