CN115507162A - Power balancing device based on mechanical-electrical integration planetary speed regulation and operation method - Google Patents

Abstract

The invention relates to the field of high-power speed regulation, in particular to a power balancing device based on electromechanical integration planetary speed regulation and an operation method thereof. The invention can be used for a power balance operation mode and can also be used for direct drive, the operation efficiency can be improved, and the requirements of all starting and operation working conditions of a driven equipment system are met.

Description

Power balancing device based on mechanical-electrical integration planetary speed regulation and operation method

Technical Field

The invention relates to the field of high-power speed regulation, in particular to a power balancing device based on electromechanical integrated planetary speed regulation and an operation method thereof, which are suitable for the field of industrial speed regulation driving, such as devices of a boiler feed pump of a power station, a steam-driven compressor in petrochemical and natural gas industries and the like, and can be used for a power balancing operation mode and direct driving.

Background

The high-capacity thermal power generating unit has remarkable effect in energy conservation in China, thermal power is still ballast stone supplied by electric power in China at the present stage and in a quite long certain period in future, based on the intrinsic endowment of the energy in China, a batch of advanced coal-electricity generating units are still newly built in China to ensure the energy safety, and under the constraint of the current double-carbon targets, the newly built units adopt more advanced technologies as far as possible, so that the efficiency and the reliability are improved to the maximum degree.

Related research institutions in China research the efficiency problem of driving auxiliary machines by small turbines of thermal power plants and provide solutions, the east China Power design institute discloses a back pressure type small turbine driving water supply pump system and method for speed regulation of a variable frequency generator in 2013, and a straight condensing type small turbine driving water supply pump system and method for speed regulation of a power frequency generator, and provides a method for controlling the rotating speed of the small turbine by partially or completely replacing a regulating valve mode through controlling the output mode of the power frequency or variable frequency generator so as to control the rotating speed of a water supply pump set, and can utilize the generator to generate electricity, so that the output of the small turbine is fully utilized, the regulating valve of the small turbine keeps 70-100% of opening degree for a long time, throttling loss is greatly reduced, and the operating efficiency of the small turbine is improved. The limitation of the scheme is that the power of the small turbine is always larger than that of the water feeding pump, so that the generator is in a normal power generation state, the small turbine is still selected according to design specifications (GB 50660-2011) of large and medium thermal power plants, and the capacity of the small turbine cannot be flexibly selected; the scheme of the power frequency generator needs a matched speed regulating gear box which is provided with a hydraulic coupler with a gear box or a speed regulating planetary gear box with a hydraulic torque converter and can only carry out unidirectional power transmission, wherein the hydraulic coupler has slip, the efficiency loss is still large, and the hydraulic coupler is imported equipment with high price; the scheme of the variable-frequency generator changes the output of the generator by adjusting an excitation system of the variable-frequency generator, on one hand, an auxiliary system adopts a synchronous generator with excitation to make the system too complicated, and the reliability is relatively reduced, and on the other hand, the method for controlling the output of the generator by excitation can make the power angle of the synchronous generator work at 90 degrees and be at the critical point of a stable and unstable area, and the control difficulty is very high.

The university and colliery group respectively applied for 2014 and 2018 'an energy-saving boiler feed pump drive system for a thermal power plant and a utility model patent of a motor-small turbine variable-speed dual drive system', which can realize the full-open operation of a small turbine valve, but the former has the limitation that the small turbine model selection capacity needs to reach about twice the power of a feed pump shaft, so that the model selection capacity is too large and is not suitable for the current situation, a planetary gear speed regulating device adopted in a shaft system is still the speed regulating planetary gear box with the hydraulic torque converter, the feed pump adopts full-capacity speed regulation, and the speed regulating equipment model selection capacity is large; the latter relates to a winding type permanent magnet speed regulation device, and the miniaturization degree is not enough, so that the integral planetary gear speed regulation device has larger volume.

The university and TongLian coal mine group has applied for "an energy-saving boiler draught fan actuating system for thermal power plant" respectively in 2014 and 2015, the utility model patent of the shafting structure that the large-scale axial-flow fan vapour of power plant boiler was two driven of steam electricity "to in 2015 in Shanxi with Hua generate electricity 2X 660MW unit implementation transformation, realize that internal first example draught fan vapour and electricity is two to be driven, this case belongs to the power balance mode of the fixed rotational speed of shafting, still can not realize the variable speed.

In 2018, peak energy technology (Beijing) Inc. and Yangrong et al disclose a multi-speed steam-electric dual-drive system for an axial flow fan, which belongs to the power balance category of shafting variable speed, but the device is not perfect.

A second-stage 2 x 1000MW unit of a Huaneng Renjin power plant is put into operation at the end of 2021 years, a main water supply pump 8 of the Huaneng Renjin power plant is driven by a steam extraction back pressure type small steam turbine (hereinafter referred to as a back extraction type small turbine 46), specifically shown in figure 1, a synchronous generator 47 is arranged to balance surplus power of a shaft system and feed back the surplus power to a service power system, a power balance scheme of the main water supply pump 8 is realized for the first time, the power balance motor adopts the synchronous generator 47, due to the existence of a coaxial exciter 48 and an excitation system, the system is complex, the avoidance rate of critical rotating speed is relatively insufficient, the selection of the motor needs to simultaneously meet the maximum torque working condition and the maximum power working condition, so that the selection power is large, the power balance motor is driven by a full-capacity converter (frequency converter), the selection capacity of the converter is large, a pre-positioned pump 34 is decelerated by the main water supply pump 8 through a gear box 45 and is driven by a long shaft 44, and the variable-speed operation is realized, and the shaft system is very long.

At present, 1000MW units are mostly prone to be provided with a 1 x 100% capacity steam-driven water feeding pump, the reliability level of a small steam turbine and the reliability level of the water feeding pump are equivalent to that of a main machine, the 1 x 100% capacity configuration is beneficial to the 2 x 50% capacity configuration from the aspects of efficiency and manufacturing cost, but the 1000MW units are all ultra-supercritical unit direct-current boilers, the trip of the 100% capacity water feeding pump can cause the trip of the units, and the 1 x 100% capacity configuration cannot be adopted on occasions with higher reliability requirements.

Disclosure of Invention

The invention provides a power balancing device based on electromechanical integrated planetary speed regulation and an operation method thereof, which are suitable for the field of industrial speed regulation driving, such as equipment of a boiler feed pump of a power station, a steam-driven compressor in petrochemical and natural gas industries and the like, can be used for a power balance operation mode and direct driving, can improve the operation efficiency, and meet the requirements of all starting and operation working conditions of a driven equipment system. Shanxi honor Shida science and technology Limited liability company discloses a utility model patent of a mechanical and electrical integration planetary speed regulation device with full-range speed regulation, the invention improves partial electrical and mechanical devices and systems on the basis of the utility model patent, and provides a power balancing device based on mechanical and electrical integration planetary speed regulation.

The invention is realized by adopting the following technical scheme: a power balancing device based on mechanical and electrical integration planetary speed regulation (hereinafter referred to as: the device) comprises a main motor, an auxiliary motor, a main driving end gear, a differential planetary mechanism, an A speed regulation end idler, an A speed regulation end gear, an A clutch output end gear, an A clutch output end idler, an A speed regulation motor, an A frequency converter, an A soft start device, a main motor bypass switch, a B speed regulation end idler, a B speed regulation end gear, a B clutch output end gear, a B clutch output end idler, a B speed regulation motor, a B frequency converter, a B soft start device, an auxiliary motor bypass switch, an A speed regulation motor incoming line switch, a B speed regulation motor incoming line switch, a main motor incoming line switch, an auxiliary motor incoming line switch and a service electric system, wherein an inner gear ring input shaft of the differential planetary mechanism is connected with the main driving end gear, and the main driving end gear is connected with the A clutch output end gear through the A clutch output end idler, the main driving end gear is also connected with the output end gear of the B clutch through the output end idle gear of the B clutch, the output end gear of the A clutch is connected with the output shaft of the A clutch, the output end gear of the B clutch is connected with the output shaft of the B clutch, the main motor is connected with the main driving end gear, the secondary motor is connected with the main motor through the coupler, the sun gear of the differential planetary mechanism is connected with external equipment, the secondary motor is also connected with other external equipment, the planet carrier of the differential planetary mechanism is connected with the speed regulation end idle gear of the A, the speed regulation end idle gear of the A is meshed with the speed regulation end gear of the A, the speed regulation end gear of the A is connected with the speed regulation motor of the A, the planet carrier of the differential planetary mechanism is also connected with the speed regulation end idle gear of the B, the speed regulation end idle gear of the B is meshed with the speed regulation end gear of the B, the speed regulation end gear of the B is connected with the speed regulation motor of the B, the B speed regulation end idler is connected with an input shaft of the B clutch, an inversion end of an A frequency converter is connected with an A speed regulation motor, a rectification end is connected to a plant power system through an A transformer and a service power system incoming line switch of the A speed regulation motor, an inversion end of the B frequency converter is connected with the B speed regulation motor, the rectification end is connected to the plant power system through the B transformer and the service power system incoming line switch of the B speed regulation motor, an output end of an A soft start device is connected with a main motor, an input end is connected with the plant power system through the main motor incoming line switch, one end of a main motor bypass switch is connected with the main motor incoming line switch, the other end of the main motor bypass switch is connected with the main motor, an output end of the B soft start device is connected with an auxiliary motor, the input end is connected with the plant power system through the auxiliary motor incoming line switch, one end of the auxiliary motor bypass switch is connected with an auxiliary motor incoming line switch, and the other end of the auxiliary motor is connected with the auxiliary motor.

The operation method of the device comprises the following steps: when the device is normally started, the A frequency converter drives the A speed regulating motor to carry out frequency conversion speed regulation starting, so that the A speed regulating end gear, the A speed regulating end idler and the planet carrier are driven to increase in speed, the B frequency converter drives the B speed regulating motor to carry out frequency conversion speed regulation starting, so that the B speed regulating end gear, the B speed regulating end idler and the planet carrier are driven to increase in speed, the A speed regulating end idler increases in speed to enable the A clutch to be connected to drive the A clutch output end gear, the A clutch output end idler and the main drive end gear to increase in speed (at the moment, the B clutch is not connected), so that the main motor, the auxiliary motor and the inner gear ring are driven to increase in speed, so that the sun gear drives the external connection equipment to increase in speed, when the output of the A frequency converter and the B frequency converter reaches the reverse highest frequency, the main motor and the auxiliary motor reach the synchronous rotating speed corresponding to the power frequency, and at the moment, the rotating speed of the external connection equipment reaches the upper limit of speed regulation rotating speed in a low-speed interval. Then, the main motor and the auxiliary motor are respectively started (soft grid connection) through the A soft start device and the B soft start device, after the rated voltage is reached, the main motor bypass switch and the auxiliary motor bypass switch are switched on, the A soft start device and the B soft start device quit operation, the main motor and the auxiliary motor start to work, then the output frequencies of the A frequency converter and the B frequency converter are gradually reduced, the A clutch is disengaged along with the reduction of the rotating speed of the A speed regulating motor and the B speed regulating motor, the rotating speed of the sun wheel is increased, the external connection equipment is driven to continuously increase the speed, and the high-speed interval speed regulating working condition is entered.

When the external connection equipment is switched to normal work, namely shaft power can be input into the device (the sun gear), power flow is reversed, power is input by the main motor and the auxiliary motor, and output power of the sun gear is converted into input power of the sun gear, and output power of the main motor and the auxiliary motor is output.

When the main motor, the auxiliary motor, the A speed regulating motor or the A frequency converter, the B speed regulating motor or the B frequency converter have partial or all faults and cannot output power outwards through the electric loop, the B clutch is engaged, the differential planetary mechanism becomes a gear box with a fixed speed ratio, and mechanical power can still be output outwards through a main motor shaft system and an auxiliary motor shaft system which are connected through the inner gear ring.

When the speed regulating motor A and the speed regulating motor B lose power, the clutch A is engaged, and the differential planetary mechanism is a constant speed ratio gearbox, so that the shaft power can be input by the inner gear ring and output from the sun gear.

When the speed regulating motor A and the speed regulating motor B lose power, the clutch B is engaged, and the differential planetary mechanism is a constant speed ratio gearbox, so that the shaft power is input by the sun gear, and the shaft power is output from the inner gear ring.

When the A speed regulating motor and the B speed regulating motor are both in power failure, the A clutch and the B clutch are not engaged, the inner gear ring and the sun gear are in decoupling states and are respectively in free driven states, the main motor or the auxiliary motor connected with the inner gear ring drives the external equipment at the other end at a constant speed, or the main motor and the auxiliary motor drive the external equipment at the other end at a constant speed together, and the external equipment connected with the sun gear can run autonomously.

When the main motor and the auxiliary motor are both in power loss and the sun gear input shaft power is used for variable speed operation, the rotating speed of the speed regulating motor A or the speed regulating motor B is regulated, the power of the inner gear ring constant-speed output shaft can be realized, and the power of the variable-speed output shaft can also be realized.

The main motor and the auxiliary motor can be mutually standby, the auxiliary motor can also take peak output, and the overall operation efficiency of the equipment is improved.

The auxiliary motor and the matched soft start device, the B speed regulating motor and the matched B frequency converter can be eliminated in the scheme, and the scheme can be used for power balance speed regulation of a shafting and can also be used for direct speed regulation driving.

The other scheme adopted by the invention is as follows: a power balancing device based on electromechanical integration planetary speed regulation comprises a main motor, a main driving end gear, a differential planetary mechanism, an A speed regulation end idler, an A speed regulation end gear, an A clutch output end gear, an A clutch output end idler, an A speed regulation motor, an A frequency converter, a B speed regulation end idler, a B speed regulation end gear, a B clutch output end gear, a B clutch output end idler, a B speed regulation motor, a B frequency converter, an A speed regulation motor incoming line switch, an A soft start device, a main motor bypass switch, a B speed regulation motor incoming line switch, a main motor incoming line switch, a service electric system, a voltage reduction power supply, a reactor, a main motor incoming line voltage reduction switch and a main motor bypass voltage reduction switch, wherein an inner gear ring input shaft of the differential planetary mechanism is connected with the main driving end gear, and the main driving end gear is connected with the A clutch output end gear through the A clutch output end idler, the main drive end gear is also connected with the output end gear of the B clutch through the output end idler of the B clutch, the output end gear of the A clutch is connected with the output shaft of the A clutch, the output end gear of the B clutch is connected with the output shaft of the B clutch, the main motor is connected with the main drive end gear, the sun gear of the differential planetary mechanism is connected with external equipment, the main motor is also connected with other external equipment, the planet carrier of the differential planetary mechanism is connected with the speed regulation end idler of the A, the speed regulation end idler of the A is meshed with the speed regulation end gear of the A, the speed regulation end gear of the A is connected with the speed regulation motor of the A, the planet carrier of the differential planetary mechanism is also connected with the speed regulation end idler of the B, the speed regulation end idler of the B is meshed with the speed regulation end gear of the B, the speed regulation end idler of the B is connected with the speed regulation motor of the B, and the speed regulation end idler of the B is connected with the input shaft of the B clutch, the A frequency converter inversion end is connected with the A speed regulating motor, the rectification end is connected to a station electric system through the A transformer and the A speed regulating motor incoming line switch, the B frequency converter inversion end is connected with the B speed regulating motor, the rectification end is connected to the station electric system through the B transformer and the B speed regulating motor incoming line switch, the output end of the A soft starting device is connected with the main motor, the input end is connected with a step-down power supply through the main motor incoming line step-down switch, one end of the main motor bypass step-down switch is connected with the main motor incoming line step-down switch, the other end is connected with the main motor, one end of the reactor is connected with the main motor, the other end is connected with the station electric system through the main motor incoming line switch, one end of the main motor bypass switch is connected with the main motor incoming line switch, and the other end is connected with the main motor.

According to the power balancing device based on the electromechanical integrated planetary speed regulation, the speed regulating motor A and the speed regulating motor B are driven by the frequency converter A and the frequency converter B respectively in a master-slave control mode.

In the power balancing device based on the electromechanical integration planetary speed regulation, the transformer A and the transformer B can be phase-shifting transformers.

According to the power balancing device based on the electromechanical integration planetary speed regulation, the idler wheel at the output end of the clutch A is a two-stage idler wheel at the output end of the clutch A, the idler wheel at the output end of the clutch B is a one-stage idler wheel at the output end of the clutch B, other stages can be adopted for matching the center distance or the steering of gears, the idler wheels are arranged at other positions, and the gears at the output ends of the two clutches are in opposite steering.

When the external equipment connected with the sun gear of the differential planetary mechanism comprises the main water feeding pump, the main water feeding pipeline switching system of the main water feeding pump is formed by arranging the water feeding quick closing valve, the water feeding main valve and the water feeding bypass regulating valve in parallel, wherein the sum of the flow capacities of the water feeding quick closing valve and the water feeding main valve is 100 percent.

The invention has the beneficial effects that:

1) The power flow of the power balance device based on the electromechanical integrated planetary speed regulation can realize bidirectional flow, namely, the power can be input or output to external connection equipment through the sun gear, and correspondingly, the power balance motor connected with the inner gear ring transmits electric power to an electric system or takes the electric power.

2) The invention can realize that the differential planetary mechanism is used as a gear box with a fixed speed ratio under the condition that all electrical equipment of the power balancing device based on the electromechanical integrated planetary speed regulation have faults.

3) The steam-driven water feeding pump is applied to the steam-driven water feeding pump of the power station boiler, can realize the operation mode of steam-driven, electric and steam-electricity combined driving, can improve the efficiency, reliability and flexibility of the pump set, and is beneficial to energy conservation, emission reduction and deep peak regulation of a thermal power generating unit.

4) The invention is applied to the steam-driven feed water pump of the power station boiler, can realize the full-open operation of the small turbine valve without adjustment in a steam-electricity combined driving operation mode, and can cancel the adjustment stage in design to further improve the efficiency.

5) The invention is applied to the steam feed pump of the power station boiler, can flexibly select the capacity of the small steam turbine, and further can realize the model selection with the highest unit efficiency as the optimization target.

6) The invention is applied to the steam-driven water-feeding pump of the power station boiler, and the device can realize the RB function through the self characteristic of the device under the condition that a small turbine of a unit (especially a once-through boiler unit) which is provided with the 1 x 100 percent capacity steam pump trips, and the device does not need to trip the unit, and can be applied to the occasions which adopt the 1 x 100 percent capacity steam-driven water-feeding pump configuration and have higher requirement on reliability.

7) The invention is applied to the steam feed water pump of the power station boiler, and can cancel the starting pump in the conventional configuration due to the starting function of an electric mode.

8) The invention is applied to the steam-driven feed pump of the power station boiler, the power balance motor can adopt an asynchronous motor which is a 4-pole motor, compared with a 2-pole large-power motor, the 4-pole motor is a rigid rotor, is more mature, stable and reliable, has higher efficiency than a plurality of pole motors, and has more obvious advantages than a synchronous motor in technical economy.

9) The invention is applied to the steam-driven feed pump of the power station boiler, and can realize that most balance power is transmitted by the power-frequency asynchronous motor which runs at a constant speed, while less balance power is transmitted by the speed-regulating motor, and the capacity of the frequency converter is matched with that of the speed-regulating motor.

10 The invention is applied to the steam feed pump of the power station boiler, can realize that the preposed pump is directly driven by the power balance motor at a constant speed, and does not need to be provided with a reduction box and a long shaft.

Drawings

Fig. 1 is a schematic axial structure diagram of a 1000MW ultra-supercritical secondary reheating double-machine regenerative unit back-pumping type small-machine driven water feed pump set based on the existing power balance principle.

Fig. 2 is a schematic diagram a of a shaft system structure of a power balance device based on mechatronic planetary speed regulation and used for a steam feed pump set of a power station boiler.

Fig. 3 is a schematic diagram of an electrical system of a power balancing device based on electromechanical integrated planetary speed regulation.

Fig. 4 is a power flow schematic diagram (electric) of a starting condition of a power balancing device based on mechanical and electrical integration planetary speed regulation.

Fig. 5 is a schematic power flow diagram of the operation condition (planet carrier reversal) of the power balancing device based on the electromechanical integrated planetary speed regulation, wherein a is electric and b is fed.

Fig. 6 is a schematic power flow diagram of the operation condition (forward rotation of the planet carrier) of the power balancing device based on electromechanical integrated planetary speed regulation, wherein a is electric and b is fed.

FIG. 7 is a diagram of a water supply pipeline valve switching system of a power balancing device based on electromechanical integrated planetary speed regulation and used for a steam-driven water supply pump group of a power station boiler.

Fig. 8 is a schematic diagram B of a shafting structure of a power balance device based on electromechanical integrated planetary speed regulation for a steam feed pump unit of a utility boiler.

Fig. 9 is a diagram of a full-voltage/step-down switching system of a main motor of a power balancing device based on electromechanical integration planetary speed regulation.

In the figure: 1-main motor, 2-A coupler, 3-main driving end gear, 4-internal gear ring, 5-planet carrier, 6-sun gear, 7-B coupler, 8-main water feeding pump, 9-A speed regulation end idle gear, 10-A speed regulation end gear, 11-A synchronous automatic clutch, 12-A clutch output end gear, 13-A clutch output end two-stage idle gear, 14-C coupler, 15-A speed regulation motor, 16-A frequency converter, 17-B frequency converter, 18-main motor bypass switch, 19-plant power system, 20-A speed regulation motor inlet switch, 21-main motor inlet switch, 22-A soft start device, 23-B speed regulation end idle gear, 24-B speed regulation end gear, 25-B synchronous automatic clutch, 26-B clutch output end gear, 27-B clutch output end primary idle gear, 28-D coupler, 29-B speed regulating motor, 30-auxiliary motor, 31-E coupler, 32-small turbine, 33-G coupler, 34-front pump, 35-H coupler, 36-B speed regulating motor inlet switch, 37-auxiliary motor inlet switch, 38-auxiliary motor bypass switch, 39-B soft start device, 40-C synchronous automatic clutch, 41-F coupler, 42-I coupler, 43-J coupler, 44-long shaft, 45-gear box, 46-back-drawing small motor, 47-synchronous generator, 48-exciter, 49-reactor and 50-main motor inlet voltage reduction, 51-main motor bypass step-down switch 52-step-down power supply, 53-water supply quick-closing valve, 54-water supply main valve, 55-water supply bypass regulating valve, 56-A transformer and 57-B transformer.

Detailed Description

The 1000MW ultra-supercritical secondary reheating double-machine regenerative unit pumping back type small machine driven water supply pump set implementation mode of the existing power balance principle is as follows: the device comprises a small back-drawing type machine 46, a synchronous generator 47, an exciter 48, an E coupling 31, a B coupling 7, a main water supply pump 8, a G coupling 33, a front pump 34, an H coupling 35, an I coupling 42, a J coupling 43, a long shaft 44 and a gear box 45, which are connected according to the figure 1. In the operation of the unit, the valve of the back-drawing small machine 46 is fully opened, the high-power converter drives the synchronous generator 47 to operate in a speed regulation mode, so that the main water-feeding pump 8 which is coaxially connected operates in a speed regulation mode, the power difference between the back-drawing small machine 46 and the main water-feeding pump 8 is borne by the synchronous generator 47, and power exchange is carried out with a plant power system through the high-power converter.

Example 1: a power balancing device based on electromechanical integration planetary speed regulation is applied to a steam-operated feed pump of a power station boiler as an example and comprises a main motor 1 (specifically, a main power balancing motor), an A coupling 2, a main driving end gear 3, an inner gear ring 4, a planet carrier 5, a sun gear 6, a B coupling 7, a main feed pump 8, an A speed regulation end idler 9, an A speed regulation end gear 10, an A clutch 11 (specifically, an A synchronous automatic clutch), an A clutch output end gear 12, an A clutch output end two-stage idler 13, a C coupling 14, an A speed regulation motor 15, a B speed regulation end idler 23, a B speed regulation end gear 24, a B clutch 25 (specifically, a B synchronous automatic clutch), a B clutch output end gear 26, a B clutch output end one-stage idler 27, a D coupling 28, a B speed regulation motor 29, a secondary motor 30 (specifically, a secondary power balancing motor), an E coupling 31, a small steam turbine 32, an F coupling 33, a pre-pump 34 and a G coupling 35, wherein the connection mode is shown in figure 2. The speed regulation mechanism comprises an inner gear ring 4, a planet carrier 5 and a sun gear 6, wherein an A branch speed regulation mechanism of the differential planet is formed by an A speed regulation end idler gear 9, an A speed regulation end gear 10 and the planet carrier 5, an A branch speed regulation/constant speed clutch mechanism is formed by the A speed regulation end idler gear 9, an A clutch 11, an A clutch output end gear 12, a clutch output end two-stage idler gear 13 and a main drive end gear 3, and is used for starting working conditions of the device and overspeed protection of an A speed regulation motor 15 and a B speed regulation motor 29 in a sun gear output power state; the B speed regulation end idle wheel 23, the B speed regulation end gear 24 and the planet carrier 5 form a B branch speed regulation mechanism of the differential planet, and the speed regulation can be carried out together with the A branch speed regulation mechanism; the B speed regulation end idle wheel 23, the B clutch 25, the B clutch output end gear 26, the B clutch output end primary idle wheel 27 and the main driving end gear 3 form a B branch speed regulation/constant speed clutch mechanism, after an electric loop of the device is completely tripped, the differential planetary mechanism is changed into a constant speed ratio gear box working state, and the overspeed protection of the A speed regulation motor 15 and the B speed regulation motor 29 in a sun gear input power state is realized, a main water feed pump 8, a small steam turbine 32 and a front pump 34 are external equipment, the front pump 34 is connected with an auxiliary motor 30 through a G coupling 35, the small steam turbine 32 is connected with a sun gear 6 through a B coupling 7, the main water feed pump 8 is connected with the small steam turbine 32 through an F coupling 33, and the connection mode is shown in figure 2. The system is characterized by further comprising an A frequency converter 16 (specifically, an A four-quadrant frequency converter), a main motor bypass switch 18, an auxiliary power system 19, an A speed regulating motor incoming line switch 20, a main motor incoming line switch 21, an A soft start device 22 (specifically, an A solid soft start device), a B frequency converter 17 (specifically, a B four-quadrant frequency converter), a B speed regulating motor incoming line switch 36, an auxiliary motor incoming line switch 37, an auxiliary motor bypass switch 38, a B soft start device 39 (specifically, a B solid soft start device), an A transformer 56 and a B transformer 57, wherein the connection modes are shown in fig. 3.

The gear 24 at the speed regulating end of the B, the D coupler 28 and the speed regulating motor 29 of the B are not required to be arranged, and the frequency converter 17B, the transformer 57B and the incoming line switch 36 of the speed regulating motor of the B matched with the speed regulating motor 29 of the B are also not correspondingly arranged.

Taking a 1000MW unit as an example, the capacity of a small turbine just meets the requirement of the shaft power of a water supply pump set under the THA working condition of the unit, namely, the balance power is designed to be zero, the maximum balance power appears near the THA working condition of about 50 percent regardless of the high pressure and full pressure, about 9000kW, the device is always in the state of feeding power to a plant power system in the normal operation of the unit, the device is in the electric state under the TRL (full power generation in summer) working condition to make up the deficiency of the power of the small turbine, the design rotating speed of the reversing point of a planet carrier is preferably selected, for example, 63.6 percent of rated rotating speed, so that the weighted efficiency of all the operation working conditions is the highest, the power of the main motor 1 and the auxiliary motor 30 can be preferably selected, if the main motor meets all the working conditions except the high pressure and full pressure switching working condition according to the unit, and after the auxiliary motor trips according to the small turbine, the main motor and the auxiliary motor jointly meet the selection of the certain load working condition of the unit, for example, 75 percent of the rated load.

Zero-starting-up speed (unit starting working condition) of the device: the main motor bypass switch 18 and the main motor incoming line switch 21 are in an off state, the A soft start device 22 is not started, the auxiliary motor bypass switch 38 and the main motor incoming line switch 37 are in an off state, the B soft start device 39 is not started, the A speed regulation motor incoming line switch 20 is switched on, the A transformer 56 is electrified, the A frequency converter 16 is started, the output frequency of the A frequency converter 16 is gradually increased, the A speed regulation motor 15 is driven to increase in speed, the A speed regulation end gear 10 and the A speed regulation end idler gear 9 are driven to increase in speed, the A speed regulation end idler gear 9 enables the A clutch 11 to be connected and drive the A clutch output end gear 12, the A clutch output end two-stage idler gear 13 and the main drive end gear 3 to increase in speed, the main motor 1 and the inner gear ring 4 are driven to increase in speed, the planet carrier 5, the sun gear 6 and the main water feeding pump 8 are driven to increase in speed, wherein the planet carrier 5 transmits power to the A speed regulation end idler gear 9 to form a closed mechanical power cycle, and at the moment, the whole planet speed regulation mechanism forms a whole body to form a fixed speed ratio gear box. The speed regulating motor 15 of the branch a reaches the maximum reverse rotation speed, at this time, the main water feed pump 8 reaches the lower limit of the rotation speed (27.2% rotation speed, corresponding to the frequency of the frequency converter 16 of the branch a being-100 Hz) of the working speed regulating interval, which is the action condition of the speed regulating mechanism of the branch a and the speed regulating/constant-speed clutch mechanism of the branch a, the action condition of the speed regulating mechanism of the branch B is the same as that of the speed regulating mechanism of the branch a, the frequency converter 16 of the branch a and the frequency converter 17 of the branch B are in a master-slave control relationship, and the power flow in the starting process is as shown in fig. 4. When the output of the A frequency converter 16 and the output of the B frequency converter 17 reach the reverse highest frequency (-100 Hz), the main motor 1 and the auxiliary motor 30 reach the synchronous rotating speed corresponding to the power frequency, at the moment, the rotating speed of the main water feed pump 8 reaches the upper limit of the speed regulating rotating speed in the low-speed interval, and the front pump 34 also reaches the constant-speed working rotating speed. Then, the main motor incoming line switch 21 is switched on, the soft start device A22 is started in a thyristor slope voltage mode (soft grid connection), after the rated voltage is reached, the main motor bypass switch 18 is switched on, the soft start device A22 is withdrawn from operation, the main motor 1 is merged into the station power system 19, the auxiliary motor incoming line switch 37 is switched on, the soft start device B39 is started in a thyristor slope voltage mode (soft grid connection), after the rated voltage is reached, the main motor bypass switch 38 is switched on, the soft start device B39 is withdrawn from operation, the auxiliary motor 30 is merged into the station power system 19, the device finishes the starting process, and the lower limit rotating speed of the working speed regulation interval can be optimized according to the working condition.

Regulating the working rotating speed range of the water feed pump: after the device is started, the device is in the lower limit of a speed regulation rotating speed range (the planet carrier and the inner gear ring rotate in the same direction, the inner gear ring rotates at a constant speed according to the planetary differential principle, the planet carrier and the inner gear ring rotate in the same direction, the rotating speed of the sun wheel is reduced, namely when the speed regulation motor is in the upper limit of the rotating speed range, the rotating speed of the water supply pump is in the lower limit of the speed regulation range), the A speed regulation motor 15 and the B speed regulation motor 29 are in the highest rotating speed of the speed regulation ranges, the A clutch 11 is still in an engaged state, when the rotating speed of the main water supply pump 8 needs to be increased, the output frequency of the A frequency converter 16 and the B frequency converter 17 is reduced, the input end rotating speed of the clutch A11 is reduced, the output end rotating speed is unchanged, therefore, the clutch A11 is disengaged, the rotating speed of the main water feeding pump 8 is increased, when the rotating speeds of the speed regulating motor A15 and the speed regulating motor B29 are in a range from the highest rotating speed of reverse rotation to zero speed, the rotating speed range of the main water feeding pump 8 is 27.2% -63.6%, the power flow is shown in figure 5a (when the small turbine output is larger than the water feeding pump output in normal operation of the unit, the power flow is shown in figure 5B), at the moment, the small turbine 32 is not output, power is input into the inner gear ring 4 by the main motor 1 and the auxiliary electric drive 30, and power is output to the small turbine 32 and the main water feeding pump 8 by the sun gear 6. In the starting process of the unit, because the small turbine 32 does not have a steam source, the device drives the water feeding pump set to work, the small turbine is equivalent to the existing electric water feeding pump, the small turbine is in a shaft-feeding sealing vacuumizing state, the blowing effect of the small turbine is not obvious due to low rotating speed, the small turbine has a steam inlet condition along with the rise of the unit load, and after the output is born, the device gradually transits to a feeding state from an electric state and outputs power to the station power system 19. When the speed regulating motor A15 and the speed regulating motor B29 are reversed to rotate in the forward direction until the highest rotating speed of the forward rotation is reached (the frequency of the corresponding frequency converter A16 and the frequency converter B17 is 73.3Hz, the planet carrier and the inner gear ring rotate in the reverse direction, according to the planetary differential principle, the inner gear ring rotates at a constant speed, and the rotation speed of the planet carrier and the inner gear ring rotate in the opposite direction, the rotation speed of the planet carrier is increased, the rotation speed of the sun wheel is increased, namely when the speed regulating motor is in the upper limit of the rotating speed range, the main water feeding pump 8 is in the upper limit of the rotating speed of the speed regulating range), the rotating speed range of the main water feeding pump 8 is 63.6% -100%, the power flow of the device in the electric state is shown in figure 6a, the small steam turbine 32 valve is fully opened to normally operate, the power is transmitted to the main water feeding pump 8 and the sun wheel 6, the inner gear ring 4 outputs power to the main motor 1 and the auxiliary motor 30, and the planet carrier 5 outputs power to the speed regulating motor A15 and the speed regulating motor B29, and the power flow is shown in figure 6B.

The device is shut down: along with the reduction of the output of the unit, the steam inlet pressure of the small steam turbine 32 is gradually reduced, the small steam turbine 32 is switched on, the A frequency converter 16 controls the A speed regulating motor 15 and the B frequency converter 17 to control the rotating speed (reverse rotation) of the B speed regulating motor 29 to reach the upper limit of a speed regulating range, the A clutch 11 is connected, the main motor bypass switch 18 and the main motor inlet switch 21 are disconnected, the main motor 1 enters a driven rotation state, the auxiliary motor bypass switch 38 and the auxiliary motor inlet switch 37 are disconnected, the auxiliary motor 30 enters a driven rotation state, then the output frequencies of the A frequency converter 16 and the B frequency converter 17 are gradually reduced, the rotating speeds of the A speed regulating motor 15 and the B speed regulating motor 29 are reduced, when the rotating speed of the main water feeding pump 8 is also synchronously reduced to a certain rotating speed, the A frequency converter 16 and the B frequency converter 17 are stopped, the B speed regulating motor inlet switch 36 and the A speed regulating motor inlet switch 20 are disconnected, the pump set is idle, and the rotating speed gradually reaches zero.

Energy-saving and optimized operation: under different load working conditions of the unit, the balance power born by the sun gear 6 is different, so that the power of the inner gear ring 4 is different, the operation modes of the main motor 1 and the auxiliary motor 30 are determined according to the power of the inner gear ring 4, three modes of simultaneous operation of the main motor and the auxiliary motor, operation of the main motor and operation of the auxiliary motor can exist, but the main motor and the auxiliary motor are in a rotating state under the three modes, whether the main motor and the auxiliary motor work depends on whether the motor is connected to a station service system or not, the motor can be switched in through a soft start device, and the motor can be switched out by disconnecting a motor bypass switch, so that the load rate of the motor can be improved, the operation efficiency of the motor is improved, the motor can adopt an external cooling fan, and the motor is switched in during operation to further reduce loss.

Summer high load working condition: because the output of the small steam turbine 32 is insufficient under the back pressure in summer, the device enters an electric working state to supplement the output of the small steam turbine 32, if the main motor 1 is insufficient to provide the input power required by the inner gear ring 4 at the moment, the B soft start device 39 is started, then the auxiliary motor bypass switch 38 is closed, and the auxiliary motor 30 finishes starting and continuously supplementing the output.

Electric feed water pump mode: the device drives the water supply pump set to operate, and the small steam turbine is in a shaft-feeding seal vacuumizing state and keeps idling.

The steam-driven feed water pump mode that the prepositive pump is driven by the motor at a constant speed independently comprises the following steps: the main motor 1 or the auxiliary motor 30 drives the front pump 34 to operate, the A frequency converter 16 does not work, the A speed regulating motor 15 does not work, the B frequency converter 17 does not work, the B speed regulating motor 29 does not work, the B speed regulating motor is driven to idle, the small steam turbine steam inlet regulating valve is in a regulating state, and the rotating speeds of the small steam turbine 32 and the main water feeding pump 8 are controlled.

The front pump is driven by a small turbine in a coaxial variable speed mode: the electrical equipment of the whole device does not work electrically, the clutch B25 is connected, the steam inlet regulating valve of the small steam turbine is in a regulating state, the small steam turbine 32 drives the main water feeding pump 8, and the device (at the moment, the differential planetary mechanism is a gear box with a fixed speed ratio) drives the front pump 34 to operate in a variable speed mode.

And (3) fault working conditions: the mechanical part is normal when an electrical fault occurs, and the rotation of fault equipment is not influenced.

A set of speed regulating motor or matched frequency converter has faults: when the unit load is greater than about 75% THA, the power of one set of adjustable speed motor can meet the device requirement, and the unit can keep higher load; when the unit load is less than about 75 percent THA, the power of one set of speed regulating motor can not meet the requirement of the device, the steam inlet regulating valve of the small steam turbine 32 is quickly closed, the balance power of the device is reduced, the working condition which can be met by one set of speed regulating motor is controlled, and the unit operation is not influenced.

Two sets of speed regulating motors or matched frequency converters have faults: the steam inlet regulating valve of the small steam turbine 32 is quickly closed, so that the power of the small steam turbine 32 and the power of the main water feeding pump 8 are kept balanced, the small steam turbine is switched to a rotating speed control state from a valve full-open state, the main motor bypass switch 18 is disconnected, the auxiliary motor 30 is kept running, the front pump 34 is driven, and the running of the unit is not influenced.

When the water supply pump set is in operation, before two sets of speed regulating motors or matched frequency converters have faults, power flow is in a state that the sun gear 6 flows to the small steam turbine 32 (namely the device is in an electric state), after the speed regulating mechanisms of the A branch circuit and the B branch circuit are tripped, the rotating speed of the main water supply pump 8 can be reduced to reach a state of being balanced with the output of the small steam turbine 32, the A clutch can also play a role in preventing overspeed of the A speed regulating motors and the B speed regulating motors, if the rotating speed of the A speed regulating motors and the B speed regulating motors is dynamically raised to reach the highest rotating speed, the A clutch can be connected, and at the moment, the rotating speed of the main water supply pump 8 can be reduced and kept at a constant speed of 27.2 percent of rated rotating speed; when the power flow flows from the small turbine 32 to the sun gear 6 (i.e. the device is in a feed state), after the speed regulating mechanisms of the two branches A and B are tripped, the clutch B can also play a role in preventing the overspeed of the speed regulating motors A and B, if the small turbine 32 and the speed regulating motors A and B are dynamically lifted, and reach the joint rotating speed, the clutch B is jointed, the differential planetary mechanism becomes a gear box with a fixed speed ratio and synchronously operates with the main feed pump 8, and at the moment, the small turbine 32 is switched into a rotating speed control state from a valve full open state.

A power balance motor failure: the steam inlet regulating valve of the small steam turbine 32 is quickly closed, the balance power of the device is reduced, the device is controlled within the rated power of the power balance motor which does not have faults, the operation of the unit is not influenced, if only one power balance motor operates when the power balance motor trips due to faults, the two power balance motors are processed according to the fault mode, and the power balance motor which does not have faults is put into the system in a soft grid connection mode after the working condition of the system with the shafts is stable.

Two power balance motors failed (except for high load conditions in summer): the steam inlet regulating valve of the small steam turbine 32 is quickly closed, so that the power of the small steam turbine 32 and the power of the main water feeding pump 8 are kept approximately balanced, the small steam turbine 32 is switched to a rotating speed control state from a valve full open state, the A and B speed regulating motors and the matched A and B frequency converters are kept running, the frequency converter output frequency tracks the rotating speed of the small steam turbine, the inner gear ring 4 is kept running at a constant speed of about 1500rpm, the front-mounted pump 34 is driven, and the running of a unit is not influenced.

Two sets of speed regulating motors or matched frequency converters and two power balance motors all have faults (except for high load working condition in summer): the electric loop is completely tripped and disconnected, the steam inlet regulating valve of the small steam turbine 32 is quickly closed, so that the power of the small steam turbine 32, the power of the main water supply pump 8 and the power of the front-mounted pump 34 are kept balanced, the small steam turbine 32 is switched into a rotating speed control state from a valve full-open state, at the moment, under the action of torque, the idle wheel 23 at the speed regulating end of the B has a speed increasing trend, the gear 26 at the output end of the B clutch has a speed reducing trend, the B clutch is connected under a certain speed ratio, the differential planetary mechanism is changed into a constant speed ratio gear box, at the moment, the whole pump set shaft system becomes a steam-driven water supply pump set mode coaxially driven by the existing front-mounted pump, the front-mounted pump 34 operates in a variable speed mode, the speed ratio of the sun gear and the inner gear ring gear when the B clutch is connected is optimized, the front-mounted pump designed according to operate at the constant speed can be matched with a variable speed operation working condition, and the unit operation is not influenced.

Tripping operation conditions of the small steam turbine: the device is changed from output power to input power of an auxiliary power system 19, the power of a water supply pump group is changed to be borne by the device, but the device is not enough to bear the power of the water supply pump group under high load, for example, the device can bear the shaft power of the water supply pump group under about 75% of rated load of the unit (if only a main motor 1 runs at the moment, an auxiliary motor 30 is in a linkage standby state and is started in an interlocking mode, a bypass switch 38 of the auxiliary motor is directly switched on without a B soft start device 39, the auxiliary motor 30 finishes full-voltage direct start and takes out force, relay protection setting includes the mode), the unit runs under the load, the device is quickly changed from a feed state to an electric state, wherein the main motor and the auxiliary motor finish state conversion in a self-adaption mode, the state conversion of a speed regulating motor is finished by a frequency converter, and the running of the unit is not influenced.

When the unit is operated above the load, the unit control system RB operates to rapidly cut off the amount of fuel fed into the boiler to reduce the thermal load of the boiler, rapidly reduce the load of the unit to an allowable level, which lasts for several minutes due to the existence of heat accumulation, while the small turbine trip triggers the unit RB, as shown in fig. 7, rapidly close the feed water fast-closing valve 53 according to a close rate curve (preventing the occurrence of water hammer or reducing impact), keep the feed water main valve 54 fully open (the sum of the flow capacities of the feed water fast-closing valve and the feed water main valve is 100% capacity, the existing unit is provided with a 100% capacity feed water main valve and 1 30% capacity feed water bypass regulating valve), the feed water bypass regulating valve 55 is in a fully closed state (30% capacity, used when the unit is started), rapidly reduce the flow of the boiler feed water to a reasonable level, keep the main feed water pump 8 at a high rotational speed, maintain a high lift so as to prevent the unit from being overloaded, in the dynamic process, the feed water control system increases the output command in an automatic state, and the inverter control system reduces the pump set frequency of the pump unit to an overcurrent limit so that the pump unit can reduce the feed water flow rate to a normal load, and then the feed water pump load to a normal load, and the pump load can be returned to a normal load reduction speed, and the load reduction speed can be returned to a normal load reduction process, and the set up to a normal load reduction speed reduction process, and a normal load reduction process can be used when the main pump 8, and the main pump can be returned to a normal load reduction process, and a normal load reduction process can be used in a normal load reduction process, and a normal load reduction process can be returned to a normal load reduction process, the dynamic requirement of the unit on the water supply flow in the RB process is met, the pressure of a water supply system is reduced along with the reduction of the main steam pressure of the unit, the water supply quick-closing valve is gradually opened, the rotating speed of the main water supply pump 8 is gradually reduced, the water supply flow is met, the device is not overloaded, and the working condition is gradually kept stable.

The load shedding working condition of the unit is as follows: the unit is thrown load (namely the generator is disconnected, the steam turbine enters 3000rpm rotating speed control, the unit is maintained to idle at a constant speed), at the moment, the working steam source of the small steam turbine is lost, even if the standby steam source is normally put into use, if the rotating speed (output) of the main water feeding pump 8 cannot be quickly reduced, the overload condition of the unit still occurs, the overload degree is serious, the device is required to control to quickly reduce the rotating speed of the main water feeding pump 8, at the moment, the unit also needs to quickly reduce the output of the main water feeding pump 8, the target frequency and the frequency change rate of the frequency converter can be determined through debugging, so that the rotating speed of the main water feeding pump 8 is quickly reduced to the target rotating speed (the frequency of the frequency converter is quickly reduced to a frequency hopping point near zero frequency from the positive frequency, the frequency value is quickly improved after the frequency is converted into the negative frequency), the power of the main water feeding pump 8 is reduced to be within the rated output of the device, and then the water feeding target control is switched again.

Example 2: a power balancing device based on electromechanical integration planetary speed regulation takes a steam-driven water feeding pump applied to a power station boiler as an example, as shown in figure 8, the power balancing device is different from embodiment 1 in that a preposed pump 34 is connected in a different mode, specifically, the preposed pump 34, an H coupling 35, a long shaft 44, a J coupling 43, a gear box 45, a G coupling 42 and a main water feeding pump 8 are connected in sequence, the power balancing device is further different in that a C synchronous automatic clutch 40 is arranged between a main motor 1 and an auxiliary motor 30, specifically, the main motor 1, the E coupling 31, the C synchronous automatic clutch 40, an F coupling 41 and the auxiliary motor 30 are connected in sequence, the preposed pump 34 is designed to be variable in rotating speed and keeps a fixed speed ratio to synchronously operate with the main water feeding pump 8, and the auxiliary motor 30 can only work under an electric working condition.

Example 3: a power balancing device based on electromechanical integration planetary speed regulation is applied to a steam-driven feed pump of a power station boiler as an example, and is different from the embodiment 1 and the embodiment 2 in that an auxiliary motor 30 is not arranged, a voltage reduction power supply 52 is additionally arranged on a main motor 1 (if the voltage is 8kV, the voltage can be optimized, the main motor 1 is designed according to the service voltage level of 10kV, the nameplate power is 15MW, the power is the sum of the main motor and the auxiliary motor in the embodiment 1 and the embodiment 2), a reactor 49, a main motor incoming line voltage reduction switch 50 and a main motor bypass voltage reduction switch 51 are additionally arranged, and the connection mode is shown in fig. 9. When the unit normally operates, the main motor incoming line step-down switch 50 and the main motor bypass step-down switch 51 are switched on, the main motor 1 operates by adopting 8 kilovolt voltage level step-down capacity, which is equivalent to that the nameplate has power of about 11MW, so that the main motor 1 keeps higher load rate and power factor, the operation efficiency is improved, and the main motor incoming line switch 21 and the main motor bypass switch 18 are in a disconnected state; when the main motor 1 meets the working condition of insufficient output, if the small steam turbine 32 trips, the main motor incoming line switch 21 is quickly switched on, the voltage of the voltage reduction power supply 52 and the voltage of the station service system 19 are matched through the reactor 49, then the main motor bypass voltage reduction switch 51 is switched off, then the main motor bypass switch 18 and the bypass reactor 49 are switched on, so that the main motor 1 works at the voltage of 10kV, the nameplate power is recovered to be 15MW, the power requirement is met, and the operation is completed in an interlocking manner.

Claims (7)

1. The utility model provides a power balancing unit based on mechatronic planet speed governing which characterized in that: comprises a main motor (1), an auxiliary motor (30), a main driving end gear (3), a differential planetary mechanism, an A speed regulation end idle gear (9), an A speed regulation end gear (10), an A clutch (11), an A clutch output end gear (12), an A clutch output end idle gear, an A speed regulation motor (15), an A frequency converter (16), an A soft start device (22), a main motor bypass switch (18), a B speed regulation end idle gear (23), a B speed regulation end gear (24), a B clutch (25), a B clutch output end gear (26), a B clutch output end idle gear, a B speed regulation motor (29), a B frequency converter (17), a B soft start device (39), an auxiliary motor bypass switch (38), an A speed regulation motor incoming line switch (20), a B speed regulation motor incoming line switch (36), a main motor incoming line switch (21), an auxiliary motor incoming line switch (37) and a service power system (19), an inner gear ring input shaft of the differential planetary mechanism is connected with a main driving end gear (3), the main driving end gear (3) is connected with an output end gear (12) of the A clutch through an output end idler wheel of the A clutch, the main driving end gear (3) is further connected with an output end gear (26) of the B clutch through an output end idler wheel of the B clutch, the output end gear (12) of the A clutch is connected with an output shaft of the A clutch (11), and the output end gear (26) of the B clutch is connected with an output shaft of the B clutch (25) The main motor (1) is connected with a main drive end gear (3), the auxiliary motor (30) is connected with the main motor (1) through a coupler, a sun gear (6) of the differential planetary mechanism is connected with external equipment, the auxiliary motor (30) is also connected with the external equipment, a planet carrier (5) of the differential planetary mechanism is connected with an A speed regulation end idler gear (9), the A speed regulation end idler gear (9) is meshed with the A speed regulation end gear (10), the A speed regulation end gear (10) is connected with the A speed regulation motor (15), the A speed regulation end idler gear (9) is connected with an input shaft of an A clutch (11), the planet carrier (5) of the differential planetary mechanism is also connected with a B speed regulation end idler gear (23), a B speed regulation end idler wheel (23) is meshed with a B speed regulation end gear (24), the B speed regulation end gear (24) is connected with a B speed regulation motor (29), the B speed regulation end idler wheel (23) is connected with an input shaft of a B clutch (25), an A frequency converter (16) inversion end is connected with an A speed regulation motor (15), a rectification end is connected to a service power system (19) through an A transformer (56) and an A speed regulation motor lead-in switch (20), a B frequency converter (17) inversion end is connected with the B speed regulation motor (29), the rectification end is connected to the service power system (19) through a B transformer (57) and a B speed regulation motor lead-in switch (36), an A soft start device (22) output end is connected with a main motor (1), the input end is connected with the service system (19) through the main motor incoming line switch (21), one end of the main motor bypass switch (18) is connected with the main motor incoming line switch (21), the other end of the main motor incoming line switch is connected with the main motor (1), the output end of the B soft start device (39) is connected with the auxiliary motor (30), the input end is connected with the service system (19) through the auxiliary motor incoming line switch (37), one end of the auxiliary motor bypass switch (38) is connected with the auxiliary motor incoming line switch (37), and the other end of the auxiliary motor bypass switch (30) is connected with the auxiliary motor.

2. The operation method of the power balance device based on the electromechanical integration planetary speed regulation as claimed in claim 1, characterized in that: the method comprises the following steps: when the device is normally started, the A frequency converter (16) drives the A speed regulating motor (15) to carry out frequency conversion speed regulation starting, so that the A speed regulating end gear (10), the A speed regulating end idler (9) and the planet carrier (5) are driven to ascend, the B frequency converter (17) drives the B speed regulating motor (29) to carry out frequency conversion speed regulation starting, so that the B speed regulating end gear (24), the B speed regulating end idler (23) and the planet carrier (5) are driven to ascend, the A speed regulating end idler (9) enables the A clutch to be connected to drive the A clutch output end gear (12), the A clutch output end idler and the main drive end gear (3) to ascend, so that the main motor (1), the auxiliary motor (30) and the inner gear ring (4) to ascend, so that the sun gear (6) drives external connection equipment to ascend, when the outputs of the A frequency converter (16) and the B frequency converter (17) reach the reverse highest frequency, the main motor (1) and the auxiliary motor (30) reach corresponding synchronous rotating speeds, and at the external connection equipment reaches the upper limit of the rotating speed regulation speed in a low-speed interval; then, the main motor (1) and the auxiliary motor (30) are respectively started through an A soft start device (22) and a B soft start device (39), after the rated voltage is reached, a main motor bypass switch (18) and an auxiliary motor bypass switch (38) are switched on, the A soft start device (22) and the B soft start device (39) quit operation, the output frequency of the A frequency converter (16) and the output frequency of the B frequency converter (17) are gradually reduced, the A clutch (16) is disengaged along with the reduction of the rotating speed of the A speed regulating motor (15) and the B speed regulating motor (29), the rotating speed of the sun gear (6) is increased, external connection equipment is driven to continuously increase the speed, and the working condition of high-speed interval speed regulation is entered; when the external connection equipment is switched to normal work and shaft power can be input into the sun gear (6), power flow is reversed, power is input by the main motor (1) and the auxiliary motor (30), the output power of the sun gear (6) is converted into the input power of the sun gear, and the output power of the main motor (1) and the auxiliary motor (30) is output;

when the A speed regulating motor (15) and the B speed regulating motor (29) lose power, the A clutch (16) is engaged, and the differential planetary mechanism is a constant speed ratio gearbox at the moment, so that the shaft power can be input by the inner gear ring and output from the sun gear;

when the A speed regulating motor (15) and the B speed regulating motor (29) lose power, the B clutch (25) is engaged, and the differential planetary mechanism is a constant speed ratio gearbox at the moment, so that the shaft power can be input by the sun gear and output from the inner gear ring;

when the A speed regulating motor (15) and the B speed regulating motor (29) lose power, the A clutch (16) and the B clutch (25) are not engaged, the inner gear ring (4) and the sun gear (6) are in an uncoupling state and are respectively in a free driven state, the main motor (1) or the auxiliary motor (30) connected with the inner gear ring (4) drives external equipment at the other end at a constant speed, or the main motor (1) and the auxiliary motor (30) drive the external equipment at the other end at a constant speed together, and the external equipment connected with the sun gear (6) can run autonomously;

when the main motor (1) and the auxiliary motor (30) lose power and the sun wheel inputs shaft power to operate at variable speed, the rotating speed of the speed regulating motor A (15) or the speed regulating motor B (29) is adjusted, so that the power of the inner gear ring fixed-speed output shaft can be realized, and the power of the variable-speed output shaft can also be realized.

3. The utility model provides a power balancing unit based on mechatronic planet speed governing which characterized in that: comprises a main motor (1), a main drive end gear (3), a differential planetary mechanism, an A speed regulation end idler (9), an A speed regulation end gear (10), an A clutch (11), an A clutch output end gear (12), an A clutch output end idler, an A speed regulation motor (15), an A frequency converter (16), a B speed regulation end idler (23), a B speed regulation end gear (24), a B clutch (25), a B clutch output end gear (26), a B clutch output end idler, a B speed regulation motor (29), a B frequency converter (17), an A speed regulation motor incoming line switch (20), an A soft start device (22), a main motor bypass switch (18), a B speed regulation motor incoming line switch (36), a main motor incoming line switch (21), a power plant system (19), a voltage reduction power supply (52), a reactor (49), a main motor incoming line voltage reduction switch (50) and a main motor bypass differential switch (51), an internal gear ring input shaft of the planetary mechanism is connected with the main drive end gear (3), the main drive end gear (3) is connected with the A clutch output end gear (12) through the A clutch output end gear (26), the main drive end idler output end gear (3) is connected with the B clutch output end gear (11), and a clutch output shaft of the B speed regulation end idler (26), the output end gear (26) of the B clutch is connected with the output shaft of the B clutch (25), the main motor (1) is connected with the main drive end gear (3), the sun gear (6) of the differential planetary mechanism is connected with external equipment, the main motor (1) is also connected with the external equipment, the planet carrier (5) of the differential planetary mechanism is connected with the A speed regulation end idler (9), the A speed regulation end idler (9) is meshed with the A speed regulation end gear (10), the A speed regulation end gear (10) is connected with the A speed regulation motor (15), the A speed regulation end idler (9) is connected with the input shaft of the A clutch (11), the planet carrier (5) of the differential planetary mechanism is also connected with the B speed regulation end idler (23), the B speed regulation end idler (23) is meshed with the B speed regulation end gear (24), the B speed regulation end gear (24) is connected with the B speed regulation motor (29), the B speed regulation end idler (23) is connected with the input shaft of the B clutch (25), the A frequency converter (16) is connected with the A speed regulation end idler (15), the rectifying end is connected with the B speed regulation switch (19) through the A transformer (56) and the B speed regulation switch (19), the B speed regulation system is connected with the B rectifier system through the B soft switch (19), the input end is connected with a step-down power supply (52) through a main motor incoming line step-down switch (50), one end of a main motor bypass step-down switch (51) is connected with the main motor incoming line step-down switch (50), the other end of the main motor bypass step-down switch is connected with a main motor (1), one end of a reactor (49) is connected with the main motor (1), the other end of the reactor is connected with an auxiliary power system (19) through the main motor incoming line switch (21), one end of a main motor bypass switch (18) is connected with the main motor incoming line switch (21), and the other end of the main motor bypass switch is connected with the main motor (1).

4. The power balancing device based on mechatronic planetary speed regulation according to claim 1 or 3, characterized in that: the A speed regulating motor (15) and the B speed regulating motor (29) are driven by an A frequency converter (16) and a B frequency converter (17) respectively in a master-slave control mode.

5. The power balancing device based on the electromechanical integration planetary speed regulation is characterized in that: the A transformer (56) and the B transformer (57) may be phase-shifting transformers.

6. The power balancing device based on mechatronic planetary speed regulation according to claim 1 or 3, characterized in that: the idler wheel at the output end of the A clutch is a two-stage idler wheel (13) at the output end of the A clutch, the idler wheel at the output end of the B clutch is a one-stage idler wheel (27) at the output end of the B clutch, other stages can be adopted for matching the center distance or the steering of gears, and the idler wheels are arranged at other positions.

7. The power balancing device based on mechatronic planetary speed regulation according to claim 1 or 3, characterized in that: when the external equipment connected with the sun gear (6) of the differential planetary mechanism comprises a main water feeding pump, a main water feeding pipeline switching system of the main water feeding pump is formed by arranging a water feeding quick closing valve (53), a water feeding main valve (54) and a water feeding bypass adjusting valve (55) in parallel, wherein the sum of the through-flow capacities of the water feeding quick closing valve (53) and the water feeding main valve (54) is 100%.

Images