CN109995283B

CN109995283B - Power generation system

Info

Publication number: CN109995283B
Application number: CN201910264417.1A
Authority: CN
Inventors: 孙冠群
Original assignee: China Jiliang University
Current assignee: Guangzhou Xucheng Information Technology Co ltd
Priority date: 2019-03-27
Filing date: 2019-03-27
Publication date: 2020-09-11
Anticipated expiration: 2039-03-27
Also published as: CN109995283A

Abstract

A power generation system is composed of a direct current generator, a diesel engine, a speed changer and a switched reluctance generator system which are coaxially connected, wherein the switched reluctance generator system is composed of a switched reluctance generator converter, a controller and a detection device, the detection device detects various information in the switched reluctance generator converter and sends the information to the controller, the controller outputs and controls each switch tube in the switched reluctance generator converter, the switched reluctance generator converter is composed of eight switch tubes, twenty diodes, five capacitors, two reactances, three transformers and four-phase windings, each two-phase winding forms a converter which is combined with a single-phase inverter circuit and used for excitation and power generation of the switched reluctance generator, and rotor position information is combined, by time-sharing control of the eight switching tubes, multi-path alternating current and direct current power supply output is obtained, the electric energy quality is high, and the method is suitable for application in the field of independent power generation systems in field areas without power supplies.

Description

Power generation system

Technical Field

The invention relates to the field of power generation systems, in particular to a multi-alternating current and direct current power output power generation system with a simple multifunctional current transformation structure and a control method thereof, wherein the multi-alternating current and direct current power output power generation system is driven by independent diesel power.

Background

In some islands where no power grid arrives and the field engineering construction in areas such as plateau unmanned areas and desert, power supplies are needed, and some standby power supplies of important departments in cities are mostly diesel-powered generator sets, but the islands usually only can output one path of constant power supply.

The switched reluctance motor has simple structure, low cost, no winding on the rotor, small heat dissipation pressure and great application value as a generator.

In the application occasions of a plurality of diesel engine generator sets, the lighting is often needed, the production machinery also needs to be dragged, even the engineering electric welding and other operations are needed, and in practice, different secondary power supplies can only be equipped for the needs.

The converter of the switched reluctance generator system is the heart of the switched reluctance generator system, if different functions and different power outputs are realized, different converter systems are often required to be designed, and a large number of switching tubes, especially high-frequency switches, are used, so that the control complexity is greatly increased, the switching loss is increased, the cost is increased, and the reliability is reduced; in addition, the switched reluctance generator needs one path of excitation power supply when working, the traditional self-excitation mode has a simple structure but large fluctuation of output power supply and unstable working, a heavy storage battery is needed in a separate excitation mode, the workload of manual maintenance is increased, and the situation that the storage battery is difficult to replace when being placed in the field for a long time is unrealistic; therefore, the introduction of a diesel generator set into a switched reluctance generator has a great challenge, and in such occasions, a current transformation system is also required to be simple in structure and convenient to control as much as possible, the workload of manual maintenance is reduced, the switching loss is reduced as much as possible, and the reliability of the switched reluctance generator is improved.

Disclosure of Invention

Based on the above background technologies, the invention provides a structure and a control method of a diesel power unit of a complementary type direct current generator-switched reluctance generator system, which has the advantages of simple structure, convenient control, low loss, low cost, high utilization rate and multi-path alternating current and direct current power output, and is suitable for various diesel power unit systems with independent power generation.

The technical scheme of the invention is as follows:

a power generation system consists of a direct current generator, a diesel engine, a speed changer and a switched reluctance generator system, and is technically characterized in that the direct current generator, the diesel engine, the speed changer and the switched reluctance generator system are coaxially connected and jointly generate power to rotate by the diesel engine, wherein the speed changer is a speed increaser;

the switched reluctance generator system consists of a switched reluctance generator converter, a controller and a detection device, wherein the controller outputs control signals to drive each switch tube in the switched reluctance generator converter, and the detection device detects various operation signals in the switched reluctance generator system and inputs the operation signals into the controller;

the switched reluctance generator converter comprises a direct current generator output capacitor, a first phase winding, a second phase winding, a third phase winding, a fourth phase winding, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a first switching tube, a second switching tube, a third switching tube, a fourth switching tube, a fifth switching tube, a sixth switching tube, a seventh switching tube, an eighth switching tube, a first diode, a second diode, a third diode, a fourth diode, a fifth diode, a sixth diode, a seventh diode, an eighth diode, a ninth diode, a twelfth diode, an eleventh diode, a twelfth diode, a thirteenth diode, a fourteenth diode, a fifteenth diode, a sixteenth diode, a seventeenth diode, an eighteenth diode, a nineteenth diode, a twentieth diode, a first transformer, a second transformer, The third transformer, the first reactance and the second reactance are formed, the output capacitor of the direct current generator is connected with the output two ends of the direct current generator, the positive electrode of the output capacitor of the direct current generator is simultaneously connected with one end of the first phase winding, one end of the second phase winding, one end of the third phase winding and one end of the fourth phase winding, the other end of the first phase winding is connected with the anode of the sixth diode, the other end of the second phase winding is connected with the anode of the fifth diode, the other end of the third phase winding is connected with the anode of the twelfth diode, the other end of the fourth phase winding is connected with the anode of the eleventh diode, the cathode of the sixth diode is connected with the cathode of the third switch tube, the anode of the fourth switch tube, the anode of the third diode, the cathode of the fourth diode, one end of the primary winding of the first transformer, the cathode of the, The anode of the second switch tube, the anode of the first diode, the cathode of the second diode and the other end of the primary winding of the first transformer, the cathode of the twelfth diode is connected with the cathode of the seventh switch tube, the anode of the eighth switch tube, the anode of the ninth diode, the cathode of the twelfth diode and one end of the primary winding of the second transformer, the cathode of the eleventh diode is connected with the cathode of the fifth switch tube, the anode of the sixth switch tube, the anode of the seventh diode, the cathode of the eighth diode and the other end of the primary winding of the second transformer, the anode of the first switch tube, the cathode of the first diode, the anode of the third switch tube and the cathode of the third diode are connected and are connected with the anode of the first capacitor, the anode of the fifth switch tube, the cathode of the seventh diode, the anode of the seventh switch tube and the cathode of the ninth diode are connected and are connected with the anode of the second capacitor, the negative pole of the output capacitor of the direct current generator is simultaneously connected with the negative pole of a first capacitor, the negative pole of a second switch tube, the positive pole of a second diode, the negative pole of a fourth switch tube, the positive pole of a fourth diode, the negative pole of a second capacitor, the negative pole of a sixth switch tube, the positive pole of an eighth diode, the negative pole of an eighth switch tube and the positive pole of a twelfth diode, one end of a secondary winding of a first transformer is connected with the positive pole of the thirteenth diode and the negative pole of the fourteenth diode, the other end of the secondary winding of the first transformer is connected with the positive pole of the fifteenth diode and the negative pole of the sixteenth diode, the primary winding and the secondary winding of the first transformer are symmetrical in terms of ends, the negative pole of the thirteenth diode is connected with the negative pole of the fifteenth diode, the positive pole of the third capacitor and one end, the other end of a secondary winding of the second transformer is connected with the anode of the nineteenth diode and the cathode of the twentieth diode, the homonymous ends of the primary winding and the secondary winding of the second transformer are symmetrical, the cathode of the seventeenth diode is connected with the cathode of the nineteenth diode, the anode of the fourth capacitor and one end of the second reactance, the anode of the fourteenth diode is connected with the anode of the sixteenth diode, the cathode of the third capacitor, the anode of the eighteenth diode, the anode of the twentieth diode and the cathode of the fourth capacitor, the other end of the first reactance is connected with one end of a primary winding of the third transformer, the other end of the second reactance is connected with one end of a secondary winding of the third transformer, and the other end of the primary winding of; the two ends of the first capacitor, the two ends of the second capacitor, the two ends of the third capacitor, the two ends of the fourth capacitor, the connecting point of the other end of the primary winding of the third transformer and the other end of the secondary winding of the third transformer and the two ends of the negative pole point of the fourth capacitor output direct current, and the two ends of the secondary winding of the first transformer and the two ends of the secondary winding of the second transformer output alternating current;

the first capacitor is the same as the second capacitor, the third capacitor is the same as the fourth capacitor, the first transformer is the same as the second transformer, all eight switching tubes are the same, the primary winding and the secondary winding of the third transformer have the same structure and the same number of turns, and the first reactance is the same as the second reactance;

the direct current electric energy generated by the direct current generator is output outwards to be used as a direct current power supply and also used as an excitation power supply of a switch reluctance generator converter, namely the excitation power supply of each phase winding of the switch reluctance generator in the excitation stage when working;

the detection device detects rotor position information, phase winding current information and three transformer winding current information of the switched reluctance generator and uses the rotor position information, the phase winding current information and the three transformer winding current information as input of the controller, and the controller outputs driving signals to eight switching tubes in a converter of the switched reluctance generator.

The method for regulating and controlling the converter of the switched reluctance generator is technically characterized in that all switch tubes are in a disconnected state before the switched reluctance generator is put into operation;

according to the rotor position information, when a first phase winding needs to be put into operation, a first switch tube and a fourth switch tube are firstly closed, the first phase winding is charged and excited, meanwhile, a first capacitor discharges and outputs to a first transformer, according to the rotor position information and the current information of the first phase winding, the fourth switch tube is disconnected when the excitation stage of the first phase winding is finished, the first switch tube adopts a PWM mode, the first phase winding enters a power generation stage, the stored energy of the first phase winding is released to the first capacitor, the primary winding of the first transformer continues to output electric energy to the secondary winding side of the first transformer when the first switch tube is controlled to be closed in a PWM mode, the primary winding of the first transformer also charges to the first capacitor when the first switch tube is disconnected, and the duty ratio selection principle of the PWM control of the first switch tube is as follows: when the adjacent working is the second phase winding, the current of the primary winding of the first transformer is just reduced to zero when the adjacent working is the second phase winding, and if the adjacent working is not the second phase winding but the fourth phase winding, the duty ratio of PWM control of the first switching tube is 1;

according to the rotor position information, when a second phase winding needs to be put into operation, a second switching tube and a third switching tube are firstly closed, the second phase winding is charged and excited, meanwhile, a first capacitor discharges and outputs to a first transformer, according to the rotor position information and the second phase winding current information, the second switching tube is opened when the second phase winding excitation stage is finished, the third switching tube adopts a PWM mode, the second phase winding enters a power generation stage, the stored energy of the second phase winding is released to the first capacitor, the primary winding of the first transformer continues to output electric energy to the secondary winding side of the first transformer when the PWM control of the third switching tube is closed, the primary winding of the first transformer also charges to the first capacitor when the secondary winding is opened, and the duty ratio selection principle of the PWM control of the third switching tube is as follows: when the adjacent working is the first phase winding, the current of the primary winding of the first transformer is just reduced to zero when the adjacent working is the first phase winding, and if the adjacent working is not the first phase winding but the third phase winding, the duty ratio of the PWM control of the third switching tube is 1;

according to the rotor position information, when a third phase winding needs to be put into operation, a fifth switching tube and an eighth switching tube are firstly closed, the third phase winding is charged and excited, meanwhile, a second capacitor discharges and outputs to a second transformer, according to the rotor position information and the current information of the third phase winding, the eighth switching tube is disconnected when the excitation stage of the third phase winding is finished, the fifth switching tube adopts a PWM mode, the third phase winding enters a power generation stage, the stored energy of the third phase winding is released to the second capacitor, a primary winding of the second transformer continues to output electric energy to a secondary winding side of the second transformer when the PWM control of the fifth switching tube is closed, the primary winding of the second transformer also charges to the second capacitor when the secondary winding is disconnected, and the duty ratio selection principle of the PWM control of the fifth switching tube is as follows: when the adjacent working is the fourth-phase winding, the current of the primary winding of the second transformer is just reduced to zero when the adjacent working is the fourth-phase winding, and if the adjacent working is not the fourth-phase winding but the second-phase winding, the duty ratio of PWM control of the fifth switching tube is 1;

according to the rotor position information, when a fourth phase winding needs to be put into operation, a sixth switching tube and a seventh switching tube are firstly closed, the fourth phase winding is charged and excited, meanwhile, a second capacitor discharges and outputs to a second transformer, according to the rotor position information and the current information of the fourth phase winding, the sixth switching tube is opened when the excitation stage of the fourth phase winding is finished, the seventh switching tube adopts a PWM mode, the fourth phase winding enters a power generation stage, the stored energy of the fourth phase winding is released to the second capacitor, a primary winding of the second transformer continues to output electric energy to a secondary winding side of the second transformer when the seventh switching tube is closed under PWM control, the primary winding of the second transformer also charges to the second capacitor when the seventh switching tube is opened, and the duty ratio selection principle of the seventh switching tube PWM control is as follows: when the adjacent working is the third phase winding, the current of the primary winding of the second transformer is just reduced to zero when the adjacent working is the third phase winding, and if the adjacent working is not the third phase winding but the first phase winding, the duty ratio of the PWM control of the seventh switching tube is 1.

The invention has the following main technical effects:

(1) the invention firstly provides a diesel engine with two coaxial ends for respectively dragging a switch reluctance generator and a direct current generator, two diesel engines are not needed, direct current generated by the direct current generator can be used as an excitation power supply of the switch reluctance generator, the big problem of excitation of the switch reluctance generator is solved, a heavy storage battery is avoided to be carried, or a self-excitation current conversion system with complex control is designed, and meanwhile, in order to ensure the excitation electric energy of the switch reluctance generator, the direct current electric energy generated by the switch reluctance generator is supplemented to provide a load of the direct current power supply to the direct current generator, so that complementary power supply is realized, the integral utilization rate of the system is high, the control is simple and convenient, the cost performance is high, and meanwhile, a transmission and a switch reluctance generator system can be conveniently added for improving the existing direct current diesel generator set.

(2) The first transformer and the second transformer are the same, but the number of turns of the secondary winding of the first transformer and the number of turns of the primary winding of the second transformer can be different, so that boosting and reducing can be conveniently realized, and particularly, when the first transformer and the second transformer are used for outputting a direct current welding machine, the voltage can be conveniently reduced, and high-quality high-reliability high-current direct current can be output through the filtering and current-sharing protection functions of the first reactor, the second reactor and the third transformer.

(3) In the structure of the converter of the switched reluctance generator, each phase winding of the switched reluctance generator and complex excitation and power generation operation are fused in an inversion loop, excessive circuits and devices are not added, the converter can better perform the work of excitation, power generation, forward and reverse inversion, follow current and the like, cross coordination operation control is performed, each loop only needs one switching tube to perform PWM (pulse width modulation) frequent switching operation, and the other switching tubes all work in a single pulse wave mode, so that the overall switching loss is reduced; meanwhile, under the control method of the invention, the continuous alternating current of the first transformer and the second transformer can be kept to the maximum extent, or the current breaking is as short as possible, and the quality of electric energy is improved; in addition, the two groups of current transformation branch circuits (the first transformer and the second transformer) of the invention alternate voltage and current, which certainly depends on the characteristic of time-sharing operation of each phase winding of the switched reluctance generator, but objectively make the voltage and current transformation of the output end, namely the third capacitor and the fourth capacitor which are connected in parallel, naturally complement the high and low change, so that the filtering equal pressure is reduced, and the electric energy quality is higher.

(4) The power generation system can lead out six direct current power supplies and two high-frequency alternating current power supplies for users to select and use, is particularly suitable for daily power supply and engineering construction loads of areas without power grids, such as islands, deserts and the like, and can conveniently change the two sides of the third capacitor and the fourth capacitor into series connection so as to obtain one path of direct current with relatively high voltage.

Drawings

Fig. 1 shows the overall configuration of a power generation system of the present invention.

Fig. 2 is a circuit diagram of a switched reluctance generator converter according to the present invention.

Detailed Description

The power generation system of the embodiment is composed of a direct current generator, a diesel engine, a speed changer and a switched reluctance generator system, wherein the direct current generator, the diesel engine, the speed changer and the switched reluctance generator system are coaxially connected and are driven by the diesel engine with the speed of 1500r/min or 3000r/min to rotate, and the speed changer is a speed increaser with the speed increasing ratio of 10-20 times.

The switched reluctance generator system consists of a switched reluctance generator converter, a controller and a detection device, wherein the controller outputs control signals to drive eight switching tubes in the switched reluctance generator converter, and the detection device detects various operation signals such as switched reluctance generator rotor position information, phase winding current information, three transformer winding current information and the like in the switched reluctance generator system and inputs the operation signals into the controller.

The switched reluctance generator converter has a structure as shown in fig. 2, and includes a dc generator output capacitor C0, a first phase winding M, a second phase winding N, a third phase winding P, a fourth phase winding Q, a first capacitor C1, a second capacitor C2, a third capacitor C3, a fourth capacitor C4, a first switch tube V1, a second switch tube V2, a third switch tube V3, a fourth switch tube V4, a fifth switch tube V5, a sixth switch tube V6, a seventh switch tube V7, an eighth switch tube V8, a first diode D8, a second diode D8, a third diode D8, a fourth diode D8, a fifth diode D8, a sixth diode D8, a seventh diode D8, an eighth diode D8, a ninth diode D8, a twelfth diode D8, an eleventh thirteenth diode D8, a sixteenth diode D8, a fourteenth diode D8, a fifteenth diode D8, a fourteenth diode, A seventeenth diode D17, an eighteenth diode D18, a nineteenth diode D19, a twentieth diode D20, a first transformer T1, a second transformer T2, a third transformer T3, a first reactance L1, and a second reactance L2, wherein a dc generator output capacitor C0 is connected to both output ends of the dc generator, an anode of the dc generator output capacitor C0 is simultaneously connected to one end of a first phase winding M, one end of a second phase winding N, one end of a third phase winding P, and one end of a fourth phase winding Q, the other end of the first phase winding M is connected to an anode of a sixth diode D6, the other end of the second phase winding N is connected to an anode of a fifth diode D5, the other end of the third phase winding P is connected to an anode of a twelfth diode D12, the other end of the fourth phase winding Q is connected to an anode of an eleventh diode D11, a cathode of the sixth diode D6 is connected to a cathode of a third switching tube V3, an anode of a fourth switching tube V, A cathode of a fourth diode D4, one end of a primary winding N1 of a first transformer T1, a cathode of a fifth diode D5 connected with a cathode of a first switching tube V1, an anode of a second switching tube V2, an anode of a first diode D1, a cathode of a second diode D2, the other end of a primary winding N1 of a first transformer T1, a cathode of a twelfth diode D12 connected with a cathode of a seventh switching tube V7, an anode of an eighth switching tube V8, an anode of a ninth diode D8, a cathode of a twelfth diode D8, one end of a primary winding N8 of a second transformer T8, a cathode of an eleventh diode D8 connected with a cathode of a fifth switching tube V8, an anode of a sixth switching tube V8, an anode of a seventh diode D8, a cathode of an eighth diode D8, the other end of a primary winding N8 of the second transformer T8, an anode of the first switching tube V8, an anode of the first diode V8, a cathode of the first switching tube V8, a cathode of the, the anode of a fifth switching tube V5, the cathode of a seventh diode D7, the anode of a seventh switching tube V7, the cathode of a ninth diode D9, and the anode of a second capacitor C2 are connected, the cathode of a DC generator output capacitor C0 is simultaneously connected with the cathode of a first capacitor C1, the cathode of a second switching tube V2, the anode of a second diode D2, the cathode of a fourth switching tube V4, the anode of a fourth diode D4, the cathode of a second capacitor C2, the cathode of a sixth switching tube V6, the anode of an eighth diode D6, the cathode of an eighth switching tube V6, the anode of a twelfth diode D6, one end of a secondary winding N6 of the first transformer T6 is connected with the anode of a thirteenth diode D6 and the cathode of a fourteenth diode D6, the other end of the secondary winding N6 of the first transformer T6 is connected with the anode of a fifteenth diode D6 and the cathode of the first transformer T6, the primary winding N6 is symmetrically connected with the cathode of the fifteenth diode D6, and the cathode of the first transformer T6 are symmetrically connected with the anode, The anode of a third capacitor C3, one end of a first reactance L3, one end of a secondary winding N3 of a second transformer T3 is connected with the anode of a seventeenth diode D3 and the cathode of an eighteenth diode D3, the other end of the secondary winding N3 of the second transformer T3 is connected with the anode of a nineteenth diode D3 and the cathode of a twentieth diode D3, the synonym ends of the primary winding N3 and the secondary winding N3 of the second transformer T3 are symmetrical, the cathode of the seventeenth diode D3 is connected with the cathode of the nineteenth diode D3, the anode of a fourth capacitor C3 and one end of the second reactance L3, the anode of the fourteenth diode D3 is connected with the anode of a sixteenth diode D3, the cathode of the third capacitor C3, the anode of the eighteenth diode D3, the anode of the twentieth diode D3, the cathode of the fourth capacitor C3, the other end of the first reactance L3 is connected with one end of the primary winding N3 of the third transformer T3, the other end of the secondary winding N3 of the third transformer T3 is connected with the secondary winding N3, and is a synonym end short.

The first capacitor C1 is the same as the second capacitor C2, the third capacitor C3 is the same as the fourth capacitor C4, the first transformer T1 is the same as the second transformer T2, all eight switching tubes are the same, the primary winding N5 and the secondary winding N6 of the third transformer T3 are the same in structure and number of turns, and the first reactance L1 is the same as the second reactance L2.

In the control method of the power generation system of this embodiment, the dc power generated by the dc generator is output as a dc power supply, and is also used as an excitation power supply of the switched reluctance generator converter in the switched reluctance generator system, that is, an excitation power supply in an excitation phase when each phase winding of the switched reluctance generator operates.

The detection device of the switched reluctance generator system detects rotor position information, phase winding current information, three transformer winding current information, voltage information of each capacitor and the like of the switched reluctance generator and serves as input of the controller, the controller outputs driving signals to eight switching tubes in a converter of the switched reluctance generator, and the eight switching tubes are full-control power electronic devices such as IGBTs, power MOSFETs, GTRs, GTOs and the like.

The control method of a switched reluctance generator converter, such as the structure shown in fig. 2, is described in detail below, wherein before the switched reluctance generator is put into operation, all the switching tubes are in an off state, according to the working principle of the switched reluctance motor, the four-phase winding of the embodiment can be realized only according to the first-phase winding M, the second-phase winding N, the third-phase winding P and the fourth-phase winding Q, or the first phase winding M, the fourth phase winding Q, the third phase winding P, and the second phase winding N sequentially operate in a time-sharing manner, generally, the overlapping coefficient of the stator and the rotor of the switched reluctance generator is more than 0 to 0.5, and the overlapping coefficient of the switched reluctance generator of this embodiment is 0.35, that is, when the switched reluctance generator is operated in the power generation stage after the excitation stage of a certain phase winding is finished, the subsequent phase winding is already put into operation and is in the excitation stage.

According to the position information of the rotor of the switched reluctance generator, when the first phase winding M needs to be put into operation, the first switching tube V1 and the fourth switching tube V4 are closed firstly, the first phase winding M is charged and excited, and the loop is as follows: C0-M-D6-V4-C0, and at the same time, the first capacitor C1 discharges and outputs to the first transformer T1, and the loop is as follows: C1-V1-N1-V4-C1, the current of the first transformer T1 flows in the forward direction, and is rectified and output by a thirteenth diode D13, a fourteenth diode D14, a fifteenth diode D15 and a sixteenth diode D16, after being filtered by a third capacitor C3, the current is smoothed by a first reactance L1, according to the rotor position information and the current information of the first phase winding M, the fourth switching tube V4 is disconnected when the excitation phase of the first phase winding M is finished, the first switching tube V1 adopts a PWM mode, the first phase winding M enters a power generation phase, and the loop is as follows: M-D6-D3-C1-C0-M, the stored energy corresponding to the first phase winding M provides the first capacitor C1 with charge and can supply power to the external load, at the same time, the primary winding N1 of the first transformer T1 continues to output power to the side of the secondary winding N2 of the first transformer T1 in the direction of the first reactance L1 when the first switch tube is closed under PWM control, and the loop is: N1-D3-V1-N1, when the N1 loop has no voltage and the current drops slowly, when the first switching tube V1 is disconnected during PWM operation, the primary winding N1 of the first transformer T1 also charges the first capacitor C1, and the loop is: N1-D3-C1-D2-N1, when N1 is under back pressure, the current drop is accelerated, so it can be seen that the adjustment of the PWM duty cycle of the first switching tube V1 can change the current duration of the primary winding N1 of the first transformer T1, considering the requirement of better quality if the current can be continuous in the operation of the first transformer T1, so the duty cycle selection principle of the PWM control of the first switching tube V1 is: when the second phase winding N is adjacently put into operation, the current of the primary winding N1 of the first transformer T1 is required to be reduced to zero just when the second phase winding N is put into operation, at this time, it is desirable that the first transformer T1 establishes uninterrupted current and reverses, if the second phase winding N is not adjacently put into operation, the second phase winding N does not work, so it is desirable that the current in the primary winding N1 of the first transformer T1 before the subsequent second phase winding N works is slowly reduced as much as possible to maintain continuity, if the second phase winding N is not, the fourth phase winding Q is put into operation, at this time, the duty ratio of the PWM control of the first switching tube V1 is fixed to 1, the current reduction time of the primary winding N1 of the first transformer T1 is prolonged as much as possible, and the current is reduced to zero when the fourth phase winding Q and the third phase winding P enter the second phase winding N to work after the operation is finished.

According to the rotor position information, when the second phase winding N needs to be put into operation, the operation mode is similar to that of the first phase winding M, and the following is briefly introduced: the second switching tube V2 and the third switching tube V3 are firstly closed, the second phase winding N is charged and excited, and the loop: C0-N-D5-V2-C0, at the same time, the first capacitor C1 reversely discharges to the first transformer T1 along the loop C1-V3-N1-V2-C1 and outputs the discharge to the first reactance L1 direction, so that the current direction of the primary winding N1 of the first transformer T1 is opposite to that of the first phase winding M when working, the alternating output is performed, according to the rotor position information and the second phase winding current information, the second switch tube V2 is disconnected when the excitation phase of the second phase winding N is finished, the third switch tube V3 adopts the PWM mode, the second phase winding N enters the power generation phase, and the loop is: N-D5-D1-C1-C0-N, the second phase winding stored energy is released to a first capacitor, meanwhile, the first transformer T1 primary winding N1 continues to output electric energy to the first transformer T1 secondary winding N2 side when the third switching tube V3 is closed under PWM control, and the loop: the loop of N1-D1-V3-N1, N1 is no voltage, the current drops slowly, when the PWM of the third switching tube V3 is cut off, the primary winding N1 of the first transformer T1 also charges the first capacitor C1, and the loop is as follows: N1-D1-C1-D4-N1, the reduction of the back pressure current borne by N1 is accelerated, so the current duration can be adjusted by the duty ratio of the third switch tube V3, and therefore the duty ratio selection principle of the PWM control of the third switch tube V3 is as follows: when the adjacent first phase winding M is in operation, because the adjacent first phase winding M is in the inverter loop of the same inverter, the current of the primary winding N1 of the first transformer T1 is just reduced to zero when the adjacent first phase winding M is in operation, and if the adjacent first phase winding M is not in operation, but is in operation of the third phase winding P, the duty ratio of the PWM control of the third switching tube V3 is 1, because the same working condition as the first phase winding M is in operation, the working condition is different from the working condition of the first phase winding M in the current direction of the first transformer T1, and is opposite to the working condition of the first phase winding M.

Since the third phase winding P and the fourth phase winding Q are in the same current-converting and inverting loop, and the structure is the same as that of the current-converting and inverting loop in which the first phase winding M and the second phase winding N are located, their working conditions correspond to those of the first phase winding M and the second phase winding N, and only a brief description is given below:

according to the rotor position information, when the third phase winding P needs to be put into operation, the fifth switching tube V5 and the eighth switching tube V8 are firstly closed, the third phase winding P is charged and excited, at the same time, the second capacitor C2 discharges and outputs in the forward direction to the second transformer T2, according to the rotor position information and the current information of the third phase winding P, the eighth switching tube V8 is opened when the excitation phase of the third phase winding P is finished, the fifth switching tube V5 adopts the PWM mode, the third phase winding P enters the power generation phase, the stored energy of the third phase winding P is released to the second capacitor C2, the primary winding N3 of the second transformer T2 continues to output the electric energy in the forward direction to the secondary winding N4 side of the second transformer T2 when the PWM control of the fifth switching tube V5 is closed, the electric energy is rectified to the second reactance L2, the primary winding N3 of the second transformer T2 also charges the second capacitor C2 when the fifth switching tube V5 is opened, and works similarly to the first phase, the duty ratio selection principle of the PWM control of the fifth switching tube V5 is: when the fourth phase winding Q is adjacently operated, the current of the primary winding N3 of the second transformer T2 is just reduced to zero when the fourth phase winding Q is adjacently operated, and if the fourth phase winding Q is not adjacently operated, but the second phase winding N in one converter circuit is not operated, the duty ratio of the PWM control of the fifth switching tube V5 is 1.

According to the rotor position information, when the fourth phase winding Q needs to be put into operation, the sixth switching tube V6 and the seventh switching tube V7 are firstly closed, the fourth phase winding Q is charged and excited, simultaneously, the second capacitor C2 reversely discharges to the second transformer T2 for output, according to the rotor position information and the fourth phase winding Q current information, the sixth switching tube V6 is opened when the fourth phase winding Q excitation phase is finished, the seventh switching tube V7 adopts a PWM mode, the fourth phase winding Q enters a power generation phase, the fourth phase winding Q stores energy and releases to the second capacitor C2, the second transformer T2 primary winding N3 continues to reversely output electric energy to the second transformer T2 secondary winding N4 side when the seventh switching tube V7 is closed under the PWM control, the electric energy is rectified and then output to the second reactance L2, when the seventh switching tube V7 is opened, the second transformer T2 primary winding N3 also charges to the second capacitor C2, and the operation is similar to that of the second phase is carried out, the duty ratio selection principle of the PWM control of the seventh switching tube V7 is: when the third phase winding P is adjacently operated, the current of the primary winding N3 of the second transformer T2 is just reduced to zero when the third phase winding P is adjacently operated, and if the first phase winding M is not adjacently operated, the duty ratio of the PWM control of the seventh switching tube V7 is 1.

Considering that the switched reluctance generator has a strong fault tolerance during operation, but it also brings a hidden trouble of the quality of the output electric energy, such as abnormal operation of a certain phase winding, fluctuation of the rotational speed of a unit, or a fault of a component such as a capacitor, etc., it is very easy to cause imbalance between two ends of the third capacitor C3 and the fourth capacitor C4 connected in parallel, and further causes a problem of excessive pressure of a certain parallel branch current, except that the two branches are respectively connected in series with the first reactance L1 and the second reactance L2, the two branches are coupled through the action of the third transformer T3, so that the two branches are averaged, and the output electric energy is more stable at this time, and is particularly suitable for a dc welding power supply.

The above-mentioned problem that each phase winding is shifted from the excitation phase to the power generation phase when working is to be described as follows, and it is necessary to describe that, generally, the phase winding current needs to meet the requirement when the excitation phase is finished, but if the phase winding current does not meet the requirement when the maximum excitation phase time angle is reached, the excitation phase must be finished to enter the power generation phase, otherwise, the power generation efficiency will be reduced, of course, if the required phase winding current is obtained in advance before the specified maximum excitation phase angle, the excitation phase is finished in advance, which is the action principle when excitation is shifted to power generation.

Due to the above working sequence of the phase winding of the switched reluctance generator, it can be seen that the current and voltage obtained by rectifying the current by the third capacitor C3 and the fourth capacitor C4 are also cross-complementary and smoother.

It can be seen from this embodiment that the system has a total of dc generator power output U0, first capacitor C1 output UC1, second capacitor output UC2, third capacitor C3 output U3, fourth capacitor C4 output U4, and third transformer T3 side output U5, and also has two ac paths of the first transformer T1 secondary winding N2 side U1 and second transformer T2 secondary winding N4 side U2, which are filtered and then can be output.

Although the four-phase switched reluctance generator is described in the present embodiment, it can be seen from the above that, the structure and control of the switched reluctance generator for two phases or six equal even phases are the same, and therefore, the switched reluctance generator still belongs to the protection scope.

Claims

1. A power generation system is composed of a direct current generator, a diesel engine, a speed changer and a switched reluctance generator system, and is technically characterized in that the direct current generator, the diesel engine, the speed changer and the switched reluctance generator system are coaxially connected and jointly generate power to rotate by the diesel engine, wherein the speed changer is a speed increaser;

2. The power generation system according to claim 1, wherein in the method for regulating the converter of the switched reluctance generator, all the switching tubes are in an off state before the switched reluctance generator is put into operation;