An excitation control circuit with multiple de-excitation loops for an aviation three-stage power generation system

Abstract

The application discloses a kind of excitation control circuit with multiple de-excitation loop for aviation three-stage power generation system, including: resonant de-excitation capacitor C2, de-excitation switch S1, de-excitation switch S2, anti-reverse diode D1, freewheeling diode D2, freewheeling diode D3, transient voltage suppression diode D4, voltage regulating MOS tube Q1, voltage regulating MOS tube Q2, de-excitation resistor R1 and excitation winding L;Wherein, the positive terminal of DC power supply DC+ is connected to the anode of anti-reverse diode D1, the cathode of anti-reverse diode D1 is sequentially connected to the negative terminal of DC power supply DC- by de-excitation switch S1 and resonant de-excitation capacitor C2;The cathode of anti-reverse diode D1 is respectively connected to the drain of voltage regulating MOS tube Q1, the negative electrode of freewheeling diode D3 and one end of de-excitation switch S2, the source of voltage regulating MOS tube Q1 is respectively connected to the positive electrode F+ of excitation winding L, the negative electrode of freewheeling diode D2;The anode of freewheeling diode D3 is respectively connected to the negative electrode F- of excitation winding L, the drain of voltage regulating MOS tube Q2 and the negative electrode of transient voltage suppression diode D4, the other end of de-excitation switch S2 is respectively connected to the positive electrode of transient voltage suppression diode D4 and one end of de-excitation resistor R1;The anode of freewheeling diode D2, the source of voltage regulating MOS tube Q2 and the other end of de-excitation resistor R1 are respectively connected to the negative terminal of DC power supply DC-.The technical scheme of the application solves the problem that the freewheeling diode added between excitation voltages in the existing excitation circuit cannot consume the energy of magnetic field, and the de-excitation speed is slow.

Description

TECHNICAL FIELD

[0001] The present application relates to, but is not limited to, the technical field of generator excitation drive, and particularly relates to an excitation control circuit with multiple de-excitation loops for a three-stage aviation power generation system. BACKGROUND

[0002] In the traditional power generation system, voltage transients occur in transient characteristics due to load changes or engine speed changes, especially when a large load is suddenly unloaded. In the traditional way, a diode freewheeling circuit is formed by controlling the excitation switch tube, and the excitation current is consumed by the equivalent resistance of the excitation winding. The de-excitation time of this de-excitation method is slow, which leads to the fact that the electromagnetic energy in the excitation winding cannot be instantaneously reduced, further affecting the voltage transient fluctuation and the time from transient to steady state. Therefore, an effective and fast de-excitation method is particularly critical. Moreover, when the DC power supply system has an overvoltage fault, the voltage at the voltage regulation point cannot be instantaneously lowered due to the reason of the back electromotive force of the excitation winding, so that the maximum loss of overvoltage fault cannot be achieved. Therefore, the demand for effective and fast transfer or absorption of excitation winding energy is extremely urgent. SUMMARY

[0003] The purpose of the present application is to solve the above technical problems. The embodiment of the present application provides an excitation control circuit with multiple de-excitation loops for a three-stage aviation power generation system to solve the problem that the freewheeling diode added between the excitation voltages in the existing excitation circuit cannot consume the energy of the magnetic field, and the de-excitation speed is slow.

[0004] The technical scheme of the present application: the embodiment of the present application provides an excitation control circuit with multiple de-excitation loops for a three-stage aviation power generation system, which comprises: a resonance de-excitation capacitor C2, a de-excitation switch S1, a de-excitation switch S2, an anti-reverse diode D1, a freewheeling diode D2, a freewheeling diode D3, a transient voltage suppression diode D4, a voltage regulation MOS tube Q1, a voltage regulation MOS tube Q2, a de-excitation resistor R1 and an excitation winding L.

[0005] The positive terminal of the direct current power supply DC+ is connected to the positive terminal of the anti-reverse diode D1, the negative terminal of the anti-reverse diode D1 is connected to the negative terminal of the direct current power supply DC- in sequence through the de-excitation switch S1 and the resonance de-excitation capacitor C2; the negative terminal of the anti-reverse diode D1 is connected to the drain of the voltage-regulating MOS tube Q1, the negative terminal of the freewheeling diode D3 and one end of the de-excitation switch S2 respectively, the source of the voltage-regulating MOS tube Q1 is connected to the positive terminal F+ of the excitation winding L and the negative terminal of the freewheeling diode D2 respectively; the positive terminal of the freewheeling diode D3 is connected to the negative terminal F- of the excitation winding L, the drain of the voltage-regulating MOS tube Q2 and the negative terminal of the transient voltage suppression diode D4 respectively, the other end of the de-excitation switch S2 is connected to the positive terminal of the transient voltage suppression diode D4 and one end of the de-excitation resistor R1 respectively; the positive terminal of the freewheeling diode D2, the source of the voltage-regulating MOS tube Q2 and the other end of the de-excitation resistor R1 are connected to the negative terminal of the direct current power supply DC-.

[0006] Optionally, in the excitation control circuit with multiple de-excitation loops for the aviation three-stage power generation system as described above, the voltage-regulating MOS tube Q2 in the excitation control circuit is set to an open state, and the excitation working mode of the excitation control circuit is:

[0007] In the normal excitation working state, when the direct current power supply is input, the resonance de-excitation capacitor C2 is used as a filter capacitor based on the closed state of the de-excitation switch S1; the anti-reverse diode D1 is forward conducting, the voltage-regulating MOS tube Q1 is controlled to be in an open state, the excitation direct current power supply flows into the excitation winding through the voltage-regulating MOS tube Q1, and the duty cycle of the voltage-regulating MOS tube Q1 is adjusted to control the voltage of the excitation direct current power supply input into the excitation winding L, so as to achieve the purpose of excitation control.

[0008] Optionally, in the excitation control circuit with multiple de-excitation loops for the aviation three-stage power generation system as described above, further comprising: a filter capacitor C1;

[0009] The filter capacitor C1 is connected between the positive terminal DC+ of the direct current power supply and the negative terminal DC- of the direct current power supply, and is used to filter out the alternating current component in the input pulsed direct current power supply voltage, so as to smooth the voltage pulsation.

[0010] Optionally, in the excitation control circuit with multiple de-excitation loops for the aviation three-stage power generation system as described above,

[0011] In the normal excitation working condition, when the excitation winding L is controlled by adjusting the duty cycle of the excitation voltage-regulating MOS tube Q1, de-excitation is realized by consuming the energy in the excitation winding L within the cut-off time;

[0012] In the case of sudden load increase or sudden load decrease of the power generation system or in the case of power generation system failure, de-excitation is realized by consuming the energy in the excitation winding L;

[0013] Wherein, the de-excitation is realized by consuming the energy in the field winding L, and at least one of the following de-excitation modes is adopted:

[0014] Mode 1, diode freewheeling de-excitation mode;

[0015] Mode 2, resistance de-excitation mode;

[0016] Mode 3, capacitor resonance de-excitation mode;

[0017] Mode 4, combined de-excitation mode.

[0018] Optionally, in the excitation control circuit with multiple de-excitation circuits for the aviation three-stage power generation system as described above, the diode freewheeling de-excitation mode of mode 1 is:

[0019] When the de-excitation condition occurs, the input DC power supply is controlled to be cut off, and the de-excitation switch S1 and the de-excitation switch S2 are controlled to be in an open state, and the voltage regulating MOS tube Q1 is controlled to be turned off to stop providing the excitation DC power supply for the field winding L;

[0020] Based on the fact that the voltage regulating MOS tube Q2 is in a normal open state, at this time, the voltage regulating MOS tube Q2, the freewheeling diode D2 and the field winding L form a first freewheeling de-excitation circuit, the DC current in the field winding L is freewheeled through the freewheeling diode D2, and the equivalent resistance of the field winding L and the tube voltage drop of the freewheeling diode D2 in the freewheeling de-excitation circuit realize the pull-down of the excitation DC power supply voltage.

[0021] Optionally, in the excitation control circuit with multiple de-excitation circuits for the aviation three-stage power generation system as described above, the resistance de-excitation mode of mode 2 is:

[0022] When the de-excitation condition occurs, the DC power supply input is controlled to be cut off, the voltage regulating MOS tube Q1 and the voltage regulating MOS tube Q2 are controlled to be turned off immediately, the de-excitation switch S1 is controlled to be opened, and the de-excitation switch S2 is controlled to be closed; the field winding L, the forward-conducting freewheeling diode D3, the de-excitation switch S2, the de-excitation resistance R1 and the freewheeling diode D2 form a resistance de-excitation circuit, and the energy in the field winding L is consumed through the heat generation of the de-excitation resistance R1 to realize de-excitation.

[0023] Optionally, in the excitation control circuit with multiple de-excitation circuits for the aviation three-stage power generation system as described above, it comprises:

[0024] The negative pole F- of the excitation winding L is connected to a transient voltage suppression diode D4, which is used to realize passive overvoltage protection de-excitation in a fault state. In a normal excitation working condition, the negative pole voltage of the excitation winding L is kept below the voltage limit. When the load of the power generation system is suddenly unloaded, the counter electromotive force of the excitation winding L instantaneously rises, so that the negative pole voltage of the excitation winding L reaches the breakdown voltage of the transient voltage suppression diode D4. The transient voltage suppression diode D4 is reversely conducted, and a second freewheeling de-excitation circuit is formed through the transient voltage suppression diode D4, the de-excitation resistor R1, the freewheeling diode D2 and the excitation winding L, so as to quickly absorb the energy of the excitation winding L.

[0025] Optionally, in the excitation control circuit with multiple de-excitation circuits for the aviation three-stage power generation system as described above, the capacitor resonance de-excitation mode of the mode 3 is as follows:

[0026] When the de-excitation working condition occurs, the DC power input is controlled to be cut off, the control voltage MOS tube Q1 and the control voltage MOS tube Q2 are immediately turned off, the de-excitation switch S1 is controlled to be closed and the de-excitation switch S2 is controlled to be opened. At this time, the freewheeling diode D2 and the freewheeling diode D3 are forward conducted, and a capacitor resonance de-excitation circuit is formed through the excitation winding L, the freewheeling diode D3, the de-excitation switch S1, the resonance de-excitation capacitor C2 and the freewheeling diode D2. The equivalent inductance of the excitation winding L in the capacitor resonance de-excitation circuit resonates with the resonance de-excitation capacitor C2, and the excitation voltage in the excitation winding L is fed back into the resonance de-excitation capacitor C2 through the freewheeling diode D3 and the de-excitation switch S1, so that the excitation voltage is rapidly reduced.

[0027] Optionally, in the excitation control circuit with multiple de-excitation circuits for the aviation three-stage power generation system as described above, the combined de-excitation mode of the mode 4 is as follows:

[0028] When the de-excitation working condition occurs, the DC power input is controlled to be cut off, the control voltage MOS tube Q1 and the control voltage MOS tube Q2 are immediately turned off, and the de-excitation switch S1 and the de-excitation switch S2 are both controlled to be closed. At this time, the freewheeling diode D2 and the freewheeling diode D3 are forward conducted.

[0029] Firstly, a capacitor resonance de-excitation circuit is formed through the excitation winding L, the freewheeling diode D3, the de-excitation switch S1, the resonance de-excitation capacitor C2 and the freewheeling diode D2. The equivalent inductance of the excitation winding L in the capacitor resonance de-excitation circuit resonates with the resonance de-excitation capacitor C2, and part of the excitation voltage in the excitation winding L is fed back into the resonance de-excitation capacitor C2 through the freewheeling diode D3 and the de-excitation switch S1, so that the excitation voltage is rapidly reduced.

[0030] Secondly, the resistor field weakening circuit is formed by the field winding L, the freewheeling diode D3, the field weakening switch S2, the field weakening resistor R1 and the freewheeling diode D2, and the residual field voltage in the field winding L is consumed by the field weakening resistor R1 to realize fast field weakening.

[0031] The embodiment of the present application provides a field excitation control circuit with multiple field weakening circuits for an aviation three-stage power generation system, and the field excitation control circuit is characterized by the aviation three-stage power generation system, and is used for solving the problems that the freewheeling diode cannot consume the energy of a magnetic field and the field weakening speed is slow in a traditional circuit, and solving the problem that the characteristic of a field weakening resistor is changed in the traditional circuit. BRIEF DESCRIPTION OF DRAWINGS

[0032] The drawings are used to provide a further understanding of the technical scheme of the present application, and constitute a part of the specification, and are used to explain the technical scheme of the present application together with the embodiments of the present application, and do not constitute a limitation on the technical scheme of the present application.

[0033] Figure 1 The circuit structure schematic diagram of the field excitation control circuit with multiple field weakening circuits for the aviation three-stage power generation system is provided for the embodiment of the present application.

[0034] Figure 2 The principle schematic diagram of the diode freewheeling field weakening mode of the field excitation control circuit with multiple field weakening circuits is provided for the embodiment 1 of the present application.

[0035] Figure 3 The principle schematic diagram of the resistor field weakening mode of the field excitation control circuit with multiple field weakening circuits is provided for the embodiment 2 of the present application.

[0036] Figure 4A principle schematic diagram of the capacitor resonant de-excitation mode of the excitation control circuit with multiple de-excitation loops is provided for Embodiment 3 of the present application.

[0037] Figure 5 A principle schematic diagram of the combined de-excitation mode of the excitation control circuit with multiple de-excitation loops is provided for Embodiment 2 of the present application. DETAILED DESCRIPTION

[0038] In order to make the objects, technical solutions and advantages of the present application clearer, the embodiments of the present application will be described in detail below with reference to the drawings. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other in any manner without conflict.

[0039] As described in the above background, the de-excitation time of the de-excitation mode in the conventional power generation system is slow, so that the electromagnetic energy in the excitation winding cannot be instantaneously reduced, and in addition, when the overvoltage fault occurs in the direct current power supply system, it is difficult to achieve the maximum reduction of the overvoltage fault loss. Therefore, the demand for effective and rapid transfer or absorption of the excitation winding energy is extremely urgent.

[0040] Currently, there are mainly two de-excitation modes for the excitation circuit: energy transfer and energy consumption. On the one hand, energy transfer is to transfer the energy in the excitation winding to other electronic energy storage elements, so that the excitation winding voltage rapidly decreases to achieve the effect of de-excitation; for example, the inverter de-excitation, that is, using full-bridge inverter technology, the switching state of the inverter is controlled to change the current direction, so as to achieve the purpose of rapidly cutting off the current; but this mode is complex to control and is not easy to implement. On the other hand, energy consumption is mainly through the energy consumption elements (such as de-excitation resistors) connected in series or parallel with the excitation winding to consume the energy. When the excitation machine is de-excited, the de-excitation resistor is connected to the excitation loop, and the energy in the excitation winding is consumed in the form of heat through the resistor; but the commonly used de-excitation resistors are linear and nonlinear. The nonlinear resistor de-excitation speed is fast, but has the disadvantages of easy change of characteristics and short service life, and the linear resistor has a lower de-excitation speed than the nonlinear resistor. Therefore, in the same excitation loop, the single de-excitation circuit has the problem of being difficult to balance the requirements of de-excitation speed, practicality and reliability.

[0041] Therefore, it has certain practical value to design an excitation circuit with multiple de-excitation loops to improve the rapid de-excitation capability and application reliability of the excitation circuit.

[0042] In order to solve the above problems, the embodiment of the present application provides an excitation control circuit with multiple de-excitation loops for a three-stage power generation system for aviation, so as to solve the problems of large voltage transient fluctuation and long time for voltage recovery to steady state of the three-stage power generation system, optimize the transient characteristics of the three-stage power generation system, improve the dynamic response capability of the system, and ensure the basic de-excitation function under normal power generation or fault, and improve the de-excitation reliability.

[0043] The following specific embodiments provided by the present application can be combined with each other, and the same or similar concepts or processes can not be described in some embodiments.

[0044] Figure 1 The circuit structure schematic diagram of the excitation control circuit with multiple de-excitation loops for a three-stage power generation system for aviation provided by the embodiment of the present application is shown in the figure. Figure 1 The main components in the excitation control circuit with multiple de-excitation loops for a three-stage power generation system for aviation provided by the embodiment of the present application include: a resonance de-excitation capacitor C2, a de-excitation switch S1, a de-excitation switch S2, a reverse prevention diode D1, a freewheeling diode D2, a freewheeling diode D3, a transient voltage suppression diode D4, a voltage regulating MOS tube Q1, a voltage regulating MOS tube Q2, a de-excitation resistor R1, and an excitation winding L. It should be noted that in each embodiment of the present application, in order to indicate the direction of the excitation current during normal excitation, F+ and F- represent the positive and negative poles of the excitation winding respectively, and DC+ and DC- are the input of the pulsed DC power after rectification of the AC power supply.

[0045] The structure of the excitation control circuit is shown in the figure. Figure 1 In the structure of the excitation control circuit, the positive terminal DC+ of the DC power supply is connected to the positive pole of the reverse prevention diode D1, the negative pole of the reverse prevention diode D1 is connected to the negative terminal DC- of the DC power supply through the de-excitation switch S1 and the resonance de-excitation capacitor C2 in sequence, the negative pole of the reverse prevention diode D1 is connected to the drain of the voltage regulating MOS tube Q1, the negative pole of the freewheeling diode D3 and one end of the de-excitation switch S2, the source of the voltage regulating MOS tube Q1 is connected to the positive pole F+ of the excitation winding L and the negative pole of the freewheeling diode D2, the positive pole of the freewheeling diode D3 is connected to the negative pole F- of the excitation winding L, the drain of the voltage regulating MOS tube Q2 and the negative pole of the transient voltage suppression diode D4, the other end of the de-excitation switch S2 is connected to the positive pole of the transient voltage suppression diode D4 and one end of the de-excitation resistor R1, and the positive pole of the freewheeling diode D2, the source of the voltage regulating MOS tube Q2 and the other end of the de-excitation resistor R1 are connected to the negative terminal DC- of the DC power supply.

[0046] Further, the excitation control circuit with multiple de-excitation loops provided by the embodiment of the present application further comprises a filter capacitor C1. The filter capacitor C1 is connected between the positive terminal DC+ of the DC power supply and the negative terminal DC- of the DC power supply, and is used to filter out the AC component in the input pulsating DC power supply voltage, so as to smooth the voltage pulsation.

[0047] The excitation control circuit with multiple de-excitation loops provided by the embodiment of the present application is not limited to the application object of the aviation three-stage power generation system. When the power generation system exciter normally excites, the de-excitation switch S1 is closed by default, and the de-excitation switch S2 is disconnected. The input pulsating DC power supply voltage is first filtered by the filter capacitor C1 to filter out the AC component in the DC, so as to smooth the voltage pulsation. If the input is a DC power supply, the filter capacitor C1 can be removed.

[0048] Figure 1 The excitation working principle of the circuit is as follows: under the normal excitation working condition, when the DC power supply is input, the de-excitation switch S1 is closed, so that the resonance de-excitation capacitor C2 is used as a filter capacitor; the forward diode D1 is forward conducting, and the control voltage regulating MOS tube Q1 is in an open state. The excitation DC power supply flows into the excitation winding through the voltage regulating MOS tube Q1, and the voltage of the excitation DC power supply input to the excitation winding L is controlled by adjusting the duty cycle of the voltage regulating MOS tube Q1, so as to achieve the purpose of excitation control.

[0049] The excitation control circuit with multiple de-excitation loops provided by the embodiment of the present application, under the normal excitation working condition, when the excitation winding L is controlled by adjusting the duty cycle (i.e. conduction / cutoff) of the excitation voltage regulating MOS tube Q1, in order to achieve a more ideal excitation voltage regulating effect, the energy in the excitation winding L is consumed to realize de-excitation in the cutoff time. In addition, under the condition of sudden load increase or sudden load decrease of the power generation system, or under the condition of power generation system failure, de-excitation is also required; in view of the above-mentioned conditions, the present application provides multiple de-excitation modes to realize rapid de-excitation and redundant de-excitation. In the specific implementation, the energy in the excitation winding L is consumed to realize de-excitation; at least one of the following de-excitation modes is adopted:

[0050] Mode 1, diode freewheeling de-excitation mode;

[0051] This de-excitation mode is the traditional de-excitation mode of the generator, and the de-excitation speed is relatively slow. The de-excitation loop only relies on the voltage drop of the freewheeling diode and the equivalent resistance of the excitation winding for consumption, and is suitable for occasions where the de-excitation speed is not high. The specific de-excitation principle is shown in the following embodiment 1.

[0052] Mode 2, resistance de-excitation mode;

[0053] This mode is to connect the high-power de-excitation resistor into the excitation winding to form a loop when de-excitation, and the energy of the excitation winding is consumed in the form of heat through the resistor. In addition, when the voltage of the excitation DC source suddenly increases and the duty cycle of the voltage regulating tube is not adjusted in time, the excitation current will increase, and the generated voltage will exceed the specified range of transient changes.

[0054] According to the feature that the voltage of the excitation negative terminal F- also increases, a transient voltage suppression diode is arranged, and when the voltage of the excitation negative terminal F- exceeds the steady-state range, the transient voltage suppression diode is broken down and conducts, the de-excitation resistor is connected into the excitation loop to de-excite and realize transient overvoltage protection. The specific de-excitation principle is shown in the following embodiment 2.

[0055] Mode 3, capacitor resonance de-excitation mode

[0056] This mode mainly absorbs the energy in the excitation winding through the capacitor through the resonance effect of LC, and this mode is mainly applied to de-excitation under high-frequency excitation control. The specific de-excitation principle is shown in the following embodiment 3.

[0057] Mode 4, combined de-excitation mode

[0058] The resistor de-excitation and the capacitor resonance de-excitation are combined to de-excite, which can further improve the de-excitation speed. The specific de-excitation principle is shown in the following embodiment 4.

[0059] The embodiment of the present application provides an excitation control circuit with multiple de-excitation loops for an aviation three-stage power generation system, which is characterized by the excitation loop in the aviation three-stage power generation system, and is used to solve the problems that the freewheeling diode between the excitation voltages in the traditional circuit cannot consume the energy of the magnetic field, and the de-excitation speed is slow, and is used to solve the problem that the de-excitation resistor in the traditional circuit changes the characteristics when realizing fast de-excitation. The excitation control circuit with multiple de-excitation loops provided by the embodiment of the present application can realize de-excitation by consuming the energy in the excitation winding L within the cutoff time when the duty cycle of the excitation voltage regulating MOS tube Q1 is adjusted to control the excitation winding L under normal excitation working conditions. In addition, under the conditions of sudden increase or sudden decrease of the power load of the power generation system, or under the fault condition of the power generation system, multiple de-excitation modes are provided to realize rapid de-excitation and redundant de-excitation. Specifically, de-excitation is realized by consuming the energy in the excitation winding L, and multiple de-excitation modes such as diode freewheeling de-excitation mode, resistor de-excitation mode, capacitor resonance de-excitation mode and combined de-excitation mode are provided. The excitation control circuit with multiple de-excitation loops provided by the embodiment of the present application not only can improve the de-excitation speed of the excitation machine, and further improve the dynamic response capability of the entire power generation system, but also multiple de-excitation modes are redundant, and at least the basic de-excitation function can be ensured under the fault condition. In addition, the excitation control circuit provided by the present application can also realize overvoltage protection de-excitation when the excitation voltage is too high, so as to ensure the safe operation of the power generation system.

[0060] The specific way of implementing de-excitation of the excitation control circuit with multiple de-excitation loops for the aviation three-stage power generation system provided by some embodiments of the present application is described as follows.

[0061] Referring to Figure 1 The excitation control circuit with multiple de-excitation loops for the aviation three-stage power generation system shown in the figure, during the cutoff time of the voltage regulating MOS tube Q1, and when the load of the power generation system is suddenly added or removed or a fault occurs in the power generation system and de-excitation is needed, de-excitation is performed by the ways provided by the following four embodiments. One of the de-excitation ways can be arbitrarily selected. Embodiments 1-3 are respectively one de-excitation way, and embodiment 4 is a combination of embodiment 2 and embodiment 3. The four de-excitation ways provided by the four embodiments are redundant to each other.

[0062] Embodiment 1:

[0063] Figure 2 The principle diagram of the diode freewheeling de-excitation way of the excitation control circuit with multiple de-excitation loops provided by embodiment 1 of the present application is shown in the figure.

[0064] The embodiment 1 provides a freewheeling diode D2 de-excitation way;

[0065] This de-excitation way is a traditional de-excitation way of a generator. As shown in the figure, Figure 2 During the cutoff time of the voltage regulating MOS tube Q1, and when the load of the power generation system is suddenly added or removed or a fault occurs in the power generation system and de-excitation is needed, at this time the excitation circuit is converted from excitation to de-excitation (i.e., the de-excitation working condition occurs), the control cuts off the input of the direct current power supply, controls the switch de-excitation switches S1 and S2 to be disconnected, immediately turns off the voltage regulating MOS tube Q1 through the control signal, and stops providing the excitation direct current power supply to the excitation winding L. Since the voltage regulating MOS tube Q2 is in a normal open state, at this time the voltage regulating MOS tube Q2, the freewheeling diode D2, and the excitation winding L form a first freewheeling de-excitation loop. The direct current in the excitation winding L is implemented to be freewheeled through the freewheeling diode D2, and the lowering of the excitation direct current power supply voltage is implemented through the equivalent resistance of the excitation winding L and the tube voltage drop of the freewheeling diode D2 in the freewheeling de-excitation loop.

[0066] Embodiment 2:

[0067] Figure 3 The principle diagram of the resistance de-excitation way of the excitation control circuit with multiple de-excitation loops provided by embodiment 2 of the present application is shown in the figure.

[0068] The embodiment 2 provides a resistance de-excitation way (overvoltage protection): this de-excitation way mainly converts the energy in the excitation winding L into heat loss through the de-excitation resistance R1 to achieve rapid de-excitation. As shown in the figure, Figure 3As shown, when the de-excitation condition occurs, the control cuts off the DC power input, and immediately turns off the voltage regulating MOS tube Q1 and the voltage regulating MOS tube Q2 through the control signal. And the de-excitation switch S1 is opened and the de-excitation switch S2 is closed by the program control in the system, the field winding L and the forward conducting freewheeling diode D3, the de-excitation switch S2, the de-excitation resistor R1 and the freewheeling diode D2 form a resistance de-excitation circuit, and the energy in the field winding L is consumed through the heating of the de-excitation resistor R1 to realize fast de-excitation.

[0069] The resistance de-excitation mode provided in this embodiment 2 also has overvoltage protection capability, and the realization principle is:

[0070] The transient voltage suppression diode D4 connected to the negative pole F- of the field winding L can realize passive overvoltage protection de-excitation in a fault state. In a normal excitation condition, the negative pole voltage of the field winding L is kept below a certain voltage limit. When the power generation system suddenly unloads the load, especially a large load, due to the inductance characteristic of the field winding L, the counter electromotive force of the field winding L instantaneously rises, so that the negative pole voltage of the field winding L reaches the breakdown voltage of the transient voltage suppression diode D4, and the transient voltage suppression diode D4 rapidly reverses the conduction. Through the transient voltage suppression diode D4, the de-excitation resistor R1, the freewheeling diode D2 and the field winding L, a second freewheeling de-excitation circuit is formed to quickly absorb the energy of the field winding L, and the transient characteristics of the power generation system are optimized.

[0071] Embodiment 3:

[0072] Figure 4 A principle diagram of the capacitor resonance de-excitation mode of the excitation control circuit with multiple de-excitation circuits is provided for the embodiment 3 of the application.

[0073] The capacitor resonance de-excitation mode is provided in this embodiment 3: this mode is mainly applied to de-excitation under high-frequency excitation control, such as Figure 4 As shown, when the de-excitation condition occurs, the control cuts off the DC power input, and immediately turns off the voltage regulating MOS tube Q1 and the voltage regulating MOS tube Q2 through the control signal. And the de-excitation switch S1 is opened and the de-excitation switch S2 is closed by the program control in the system, the field winding L and the forward conducting freewheeling diode D3, the de-excitation switch S2, the de-excitation resistor R1 and the freewheeling diode D2 form a resistance de-excitation circuit, and the energy in the field winding L is consumed through the heating of the de-excitation resistor R1 to realize fast de-excitation.

[0074] When a fault occurs and de-excitation is needed, the control cuts off the DC power input, controls the voltage regulating MOS tube Q1 and the voltage regulating MOS tube Q2 to quickly turn off, controls the de-excitation switch S1 to close and the de-excitation switch S2 to open, based on the reason that the current in the field winding L will not change, at this time, the freewheeling diode D2 and the freewheeling diode D3 are forward-biased, the field winding L, the freewheeling diode D3, the de-excitation switch S1, the resonance de-excitation capacitor C2 and the freewheeling diode D2 form a capacitor resonance de-excitation circuit, the equivalent inductance of the field winding L in the capacitor resonance de-excitation circuit resonates with the resonance de-excitation capacitor C2, and the field voltage in the field winding L is fed back into the resonance de-excitation capacitor C2 through the freewheeling diode D3 and the de-excitation switch S1, so that the field voltage is rapidly reduced.

[0075] In addition, the freewheeling diode D2 and the freewheeling diode D3 have the ability to prevent reverse resonance of the circuit, and the function of the anti-reverse diode D1 is mainly to isolate the filter capacitor C1, and only the capacitor C2 participates in the resonance de-excitation during de-excitation.

[0076] Embodiment 4:

[0077] Figure 5 A principle diagram of a combined de-excitation mode of the field excitation control circuit with multiple de-excitation circuits is provided for the embodiment 2 of the application.

[0078] The embodiment 4 provides a combined de-excitation mode of capacitor resonance de-excitation and resistance de-excitation, that is, a comprehensive de-excitation of the two de-excitation modes of the embodiment 2 and the embodiment 3. Figure 5 As shown in the figure, when de-excitation working conditions occur, the control cuts off the DC power input, controls the voltage regulating MOS tube Q1 and the voltage regulating MOS tube Q2 to immediately turn off, and controls the de-excitation switch S1 and the de-excitation switch S2 to close; based on the reason that the current in the field winding L will not change, at this time, the freewheeling diode D2 and the freewheeling diode D3 are forward-biased.

[0079] On the one hand, a capacitor resonance de-excitation circuit is formed by the field winding L, the freewheeling diode D3, the de-excitation switch S1, the resonance de-excitation capacitor C2 and the freewheeling diode D2; the equivalent inductance of the field winding L in the capacitor resonance de-excitation circuit resonates with the resonance de-excitation capacitor C2, and part of the energy (part of the field voltage) in the field winding L is fed back into the resonance de-excitation capacitor C2 through the freewheeling diode D3 and the de-excitation switch S1, so that the field voltage is rapidly reduced.

[0080] On the other hand, the field winding L, the forward-biased freewheeling diode D3, the de-excitation switch S2, the de-excitation resistor R1 and the freewheeling diode D2 form a resistance de-excitation circuit, and the remaining part of the energy (the remaining part of the field voltage) in the field winding L is consumed by the heating of the de-excitation resistor R1 to achieve rapid de-excitation.

[0081] In this embodiment 4, because the energy in the excitation winding is consumed by two de-excitation methods respectively, compared with the single de-excitation in embodiment 2 and embodiment 3, the combined de-excitation speed will be greatly improved, so this de-excitation method uses the LC resonance combined resistance de-excitation method to improve the de-excitation speed to realize the fast de-excitation of the generator excitation system, thereby further improving the dynamic response capability of the system.

[0082] Although the embodiments of the present application are disclosed as above, the content is only the embodiments adopted for the purpose of facilitating the understanding of the present application, and is not used to limit the present application. Any person skilled in the art of the present application can make any modification and change in the implementation form and details without departing from the spirit and scope of the present application disclosed, but the patent protection scope of the present application shall be subject to the scope defined by the appended claims.

Claims

1. An excitation control circuit having multiple de-excitation loops for an aeronautical three-stage power generation system, characterized by, Comprise: Resonant de-excitation capacitor C2, de-excitation switch S1, de-excitation switch S2, anti-reverse diode D1, freewheeling diode D2, freewheeling diode D3, transient voltage suppression diode D4, voltage regulating MOS tube Q1, voltage regulating MOS tube Q2, de-excitation resistor R1 and field winding L; Wherein, the positive terminal of the DC power supply DC+ is connected to the positive electrode of the anti-reverse diode D1, the negative electrode of the anti-reverse diode D1 is connected to the negative terminal of the DC power supply DC- in turn through the de-excitation switch S1 and the resonant de-excitation capacitor C2; the negative electrode of the anti-reverse diode D1 is connected to the drain electrode of the voltage regulating MOS tube Q1, the negative electrode of the freewheeling diode D3 and one end of the de-excitation switch S2 respectively, the source electrode of the voltage regulating MOS tube Q1 is connected to the positive electrode F+ of the field winding L and the negative electrode of the freewheeling diode D2 respectively; the positive electrode of the freewheeling diode D3 is connected to the negative electrode F- of the field winding L, the drain electrode of the voltage regulating MOS tube Q2 and the negative electrode of the transient voltage suppression diode D4 respectively, the other end of the de-excitation switch S2 is connected to the positive electrode of the transient voltage suppression diode D4 and one end of the de-excitation resistor R1 respectively; the positive electrode of the freewheeling diode D2, the source electrode of the voltage regulating MOS tube Q2 and the other end of the de-excitation resistor R1 are connected to the negative terminal of the DC power supply DC- respectively.

2. The excitation control circuit having multiple de-excitation loops for an aviation-oriented three-stage power generation system according to claim 1, characterized by, The voltage regulating MOS tube Q2 in the field control circuit is set to be in an open state, and the field working mode of the field control circuit is: In the normal field working state, when the DC power supply is input, based on the closed state of the de-excitation switch S1, the resonant de-excitation capacitor C2 is used as a filter capacitor; the anti-reverse diode D1 is forward conducting, the voltage regulating MOS tube Q1 is controlled to be in an open state, the field DC power supply flows into the field winding after passing through the voltage regulating MOS tube Q1, and the duty cycle of the voltage regulating MOS tube Q1 is adjusted to control the voltage of the field DC power supply input into the field winding L, so as to achieve the purpose of field control.

3. The field control circuit having multiple de-excitation loops for an aviation-oriented three-stage power generation system according to claim 1, characterized by, Further comprising: a filter capacitor C1; The filter capacitor C1 is connected between the positive terminal of the DC power supply DC+ and the negative terminal of the DC power supply DC-, and is used to filter out the alternating current component in the input pulsed DC power supply voltage, so as to smooth the voltage pulsation.

4. The field control circuit with multiple de-excitation loops of the aviation-oriented three-stage power generation system according to any one of claims 1-3, characterized in that, In the normal field working condition, when the field winding L is controlled by adjusting the duty cycle of the field voltage regulating MOS tube Q1, de-excitation is realized by consuming the energy in the field winding L within the cut-off time; In the case of sudden load addition or sudden load removal of the power generation system, or in the case of power generation system failure, de-excitation is realized by consuming the energy in the field winding L; Wherein, de-excitation by consuming the energy in the field winding L is realized by at least one of the following de-excitation modes: Mode 1, diode freewheeling de-excitation mode; Mode 2, resistor de-excitation mode; Mode 3, capacitor resonant de-excitation mode; Mode 4, combined de-excitation mode.

5. The field control circuit having multiple de-excitation loops for an aviation-oriented three-stage power generation system according to claim 4, characterized by, The diode freewheeling de-excitation mode of the mode 1 is: When the de-excitation working condition occurs, the input DC power supply is controlled to be cut off, the de-excitation switch S1 and the de-excitation switch S2 are controlled to be in an open state, and the voltage regulating MOS tube Q1 is controlled to be off, so as to stop providing the field DC power supply to the field winding L; Based on the voltage regulating MOS tube Q2 is in the normal open state, at this time, the voltage regulating MOS tube Q2 and freewheeling diode D2, field winding L forms the first freewheeling de-excitation circuit, the DC current in field winding L is realized freewheeling through freewheeling diode D2, and the freewheeling de-excitation circuit through the equivalent resistance of field winding L and the tube voltage drop of freewheeling diode D2 realizes the pull-down of the excitation DC power voltage.

6. The excitation control circuit having multiple de-excitation loops for an aviation-oriented three-stage power generation system according to claim 4, characterized by, The resistance de-excitation mode of the mode 2 is: When the de-excitation condition occurs, the control cuts off the DC power input, controls the voltage regulating MOS tube Q1 and the voltage regulating MOS tube Q2 to be immediately turned off, controls the de-excitation switch S1 to be opened and the de-excitation switch S2 to be closed;Field winding L and forward conducting freewheeling diode D3, de-excitation switch S2, de-excitation resistor R1, freewheeling diode D2 form a resistance de-excitation circuit, and the energy in the field winding L is consumed by the heat of the de-excitation resistor R1 to realize de-excitation.

7. The field control circuit having multiple de-excitation loops for an aviation-oriented three-stage power generation system according to any one of claims 6, characterized in that, Including: The negative pole F- of the field winding L is connected to the transient voltage suppression diode D4, which is used to realize passive overvoltage protection de-excitation in fault state, and the mode is: under normal excitation condition, the negative pole voltage of the field winding L is kept below the voltage limit, when the power system suddenly unloads the load, the counter electromotive force of the field winding L instantaneously rises, so that the negative pole voltage of the field winding L reaches the breakdown voltage of the transient voltage suppression diode D4, and the transient voltage suppression diode D4 is reversely conducted, and a second freewheeling de-excitation circuit is formed by the transient voltage suppression diode D4, the de-excitation resistor R1, the freewheeling diode D2 and the field winding L, so as to quickly absorb the energy of the field winding L.

8. The field control circuit having multiple de-excitation loops for an aviation-oriented three-stage power generation system according to claim 4, wherein The capacitor resonance de-excitation mode of the mode 3 is: When the de-excitation condition occurs, the control cuts off the DC power input, controls the voltage regulating MOS tube Q1 and the voltage regulating MOS tube Q2 to be immediately turned off, controls the de-excitation switch S1 to be closed and the de-excitation switch S2 to be opened, at this time, the freewheeling diode D2 and the freewheeling diode D3 are forward conducting, and a capacitor resonance de-excitation circuit is formed by the field winding L, the freewheeling diode D3, the de-excitation switch S1, the resonance de-excitation capacitor C2 and the freewheeling diode D2;The equivalent inductance of the field winding L in the capacitor resonance de-excitation circuit resonates with the resonance de-excitation capacitor C2, and the excitation voltage in the field winding L is fed back into the resonance de-excitation capacitor C2 after the freewheeling diode D3 and the de-excitation switch S1, so that the excitation voltage is rapidly reduced.

9. The field control circuit having multiple de-excitation loops for an aviation-oriented three-stage power generation system according to claim 4, wherein The combined de-excitation mode of the mode 4 is: When the de-excitation condition occurs, the control cuts off the DC power input, controls the voltage regulating MOS tube Q1 and the voltage regulating MOS tube Q2 to be immediately turned off, controls the de-excitation switch S1 and the de-excitation switch S2 to be closed, at this time, the freewheeling diode D2 and the freewheeling diode D3 are forward conducting; Firstly, a capacitor resonance de-excitation circuit is formed by the field winding L, the freewheeling diode D3, the de-excitation switch S1, the resonance de-excitation capacitor C2 and the freewheeling diode D2;The equivalent inductance of the field winding L in the capacitor resonance de-excitation circuit resonates with the resonance de-excitation capacitor C2, and a part of the excitation voltage in the field winding L is fed back into the resonance de-excitation capacitor C2 after the freewheeling diode D3 and the de-excitation switch S1, so that the excitation voltage is rapidly reduced; Secondly, the resistance de-excitation circuit is formed by the exciting winding L, the freewheeling diode D3, the de-excitation switch S2, the de-excitation resistor R1 and the freewheeling diode D2, and the remaining exciting voltage in the exciting winding L is consumed by the heat of the de-excitation resistor R1 to realize the fast de-excitation.

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