阅读说明：本技术 一种变频调速电机车控制系统 (Control system of variable-frequency speed-regulating electric locomotive ) 是由 陈燕珊 于 2019-11-27 设计创作，主要内容包括：本发明专利公开了一种变频调速电机车控制系统,在滤波电路前接入限流电阻14和直流接触器15组成的限流电路；由电阻13及功率开关管12组成的制动电路相结合的控制电路。本发明专利具有的优点是：1、宽幅度波动输入电压的稳压电路使该变频调速电机车可以适合当今所有的工矿企业的供电环境；2、限流电路的设计可以使电机车起动时不产生对电网的过大电流冲击,使架空电网不会因此而产生过流跳闸,从而影响整个运输系统的作业；3、由于采用再生能源制动可以比没有此项功能的变频调速电机车节电率提高10％。(The invention discloses a control system of a variable-frequency speed-regulating electric locomotive, wherein a current-limiting circuit consisting of a current-limiting resistor 14 and a direct-current contactor 15 is connected in front of a filter circuit; and a control circuit combined with a brake circuit consisting of a resistor 13 and a power switch tube 12. The invention has the advantages that: 1. the voltage stabilizing circuit of wide-amplitude fluctuation input voltage ensures that the variable-frequency speed-regulating electric locomotive can be suitable for the power supply environment of all current industrial and mining enterprises; 2. the design of the current limiting circuit can prevent the electric locomotive from generating overlarge current impact on a power grid when being started, so that the overhead power grid cannot generate overcurrent tripping, and the operation of the whole transportation system is influenced; 3. the energy saving rate of the frequency conversion speed regulation electric locomotive without the function can be improved by 10 percent by adopting the regenerative energy braking.)

1. The utility model provides a variable frequency speed governing electric locomotive control system which characterized in that: the positive end of the overhead line power supply 1 is connected into a current limiting circuit through one end of an automatic switch 11, the current limiting circuit is formed by connecting a current limiting resistor 14 and a direct current contactor 15 in parallel, the other end of the current limiting resistor 14 connected with the direct current contactor 15 in parallel is connected with a filter circuit, and the output end of the filter circuit is divided into three paths: one path of the three-phase inverter circuit is connected to the collector electrodes of three groups of double-tube type IGBT upper bridge plates in the IGBT three-phase inverter circuit, the emitter electrodes of three groups of double-tube type IGBT lower bridge plates are connected with the negative end of the power supply 1, and the connection points of the three groups of double-tube type IGBT upper bridge plates and the lower bridge plates are respectively connected with the three-phase winding of the alternating current motor; one path is connected with the bus voltage detection circuit to the 21 end of the CPU microcomputer board; one circuit is connected with the collector of a power switch tube 12 in a braking circuit, the braking circuit consists of the power switch tube 12 and a resistor 13, and the emitter of the power switch tube 12 is connected with the resistor 13; the input end of the voltage-stabilizing power supply circuit is connected with the positive end of a power supply 1, the output end of the voltage-stabilizing power supply circuit is respectively connected with the power supply end of a CPU microcomputer board 16 and the input end of a driver control circuit, the output end of the driver control circuit is connected with the signal input end of the CPU microcomputer board, the IGBT drive output end G of the CPU microcomputer board is connected with 6 IGBT grids of an IGBT three-phase inverter circuit, a chopping signal end 24 of the CPU microcomputer board is connected with the grid of a power switch tube 12 in a brake circuit, and a resistor 13 of the brake circuit is connected.

Technical Field

The invention relates to a variable frequency control circuit of a trolley locomotive.

Background

The existing trolley type variable frequency speed regulation electric locomotive has the following defects: 1. when the existing trolley type variable frequency speed regulating locomotive is started, due to the fact that considerable charging current exists in a frequency converter for a large capacitor of a filter, tripping of a power supply system is often caused; 2. the requirement of the existing frequency converter on the fluctuation range of the overhead line voltage is limited to +/-30%, and the actual fluctuation of the overhead line voltage of many industrial and mining enterprises at present often exceeds the range, so that the existing variable-frequency speed regulating locomotive cannot be suitable for smooth operation of the industrial and mining enterprises; 3. the existing trolley type variable frequency speed regulating locomotive only has resistance energy consumption braking, but does not have renewable energy source braking.

Disclosure of Invention

The invention aims to provide a control system of a variable-frequency speed-regulating electric locomotive.

The purpose of the invention is realized by the following steps: the utility model provides a frequency conversion speed governing electric locomotive control system, during the overhead line power supply 1 positive end passes through automatic switch 11 one end access current limiting circuit, current limiting circuit constitute by current limiting resistor 14 and direct current contactor 15 are parallelly connected, another termination filter circuit after current limiting resistor 14 and direct current contactor 15 are parallelly connected, filter circuit's output divides three routes: one path of the three-phase inverter circuit is connected to the collector electrodes of three groups of double-tube type IGBT upper bridge plates in the IGBT three-phase inverter circuit, the emitter electrodes of three groups of double-tube type IGBT lower bridge plates are connected with the negative end of the power supply 1, and the connection points of the three groups of double-tube type IGBT upper bridge plates and the lower bridge plates are respectively connected with the three-phase winding of the alternating current motor; one path is connected with the bus voltage detection circuit to the 21 end of the CPU microcomputer board; one path is connected with the collector of a power switch tube 12 in a braking circuit, the braking circuit consists of the power switch tube 12 and a resistor 13, and the emitter resistor 13 of the power switch tube 12; the input end of the voltage-stabilizing power supply circuit is connected with the positive end of a power supply 21C, the output end of the voltage-stabilizing power supply circuit is respectively connected with the power supply end of a CPU microcomputer board 11 and the input end of a driver control circuit, the output end of the driver control circuit is connected with the signal input end of the CPU microcomputer board, the IGBT drive output end G of the CPU microcomputer board is connected with 6 IGBT grids of an IGBT three-phase inverter circuit, the chopping signal end 24 of the CPU microcomputer board is connected with the grid of a power switch tube 12 in a brake circuit, and a resistor 13 of the brake circuit is connected.

The method adopts a voltage-stabilized power supply suitable for large-range voltage fluctuation (-35-45%); secondly, a current limiting circuit consisting of a resistor 14 and a switch 15 is connected in front of the chopper circuit; thirdly, an electric circuit combining regenerative energy braking and energy consumption braking consisting of a resistor 13 and a power switch tube 12 is adopted, and the electric circuit has the advantages that: 1. the voltage stabilizing circuit of wide-amplitude fluctuation input voltage ensures that the variable-frequency speed-regulating electric locomotive can be suitable for the power supply environment of all current industrial and mining enterprises; 2. the design of the current limiting circuit can prevent the electric locomotive from generating overlarge current impact on a power grid when being started, so that the overhead power grid cannot generate overcurrent tripping, and the operation of the whole transportation system is influenced; 3. the energy saving rate of the frequency conversion speed regulation electric locomotive without the function can be improved by 10 percent by adopting the regenerative energy braking.

Drawings

FIG. 1 is a block diagram of the circuit of the present invention;

Detailed Description

As shown in fig. 1, in a control system of a variable frequency speed-regulating electric locomotive, a positive end of an overhead line power supply 1 is connected to a current-limiting circuit through one end of an automatic switch 11, the current-limiting circuit is formed by connecting a current-limiting resistor 14 and a direct current contactor 15 in parallel, the other end of the current-limiting resistor 14 connected with the direct current contactor 15 in parallel is connected to a filter circuit, and an output end of the filter circuit is divided into three paths: one path of the three-phase inverter circuit is connected to the collector electrodes of three groups of double-tube type IGBT upper bridge plates in the IGBT three-phase inverter circuit, the emitter electrodes of three groups of double-tube type IGBT lower bridge plates are connected with the negative end of the power supply 1, and the connection points of the three groups of double-tube type IGBT upper bridge plates and the lower bridge plates are respectively connected with the three-phase winding of the alternating current motor; one path is connected with the bus voltage detection circuit to the 21 end of the CPU microcomputer board; one path is connected with the collector of a power switch tube 12 in a braking circuit, the braking circuit consists of the power switch tube 12 and a resistor 13, and the emitter resistor 13 of the power switch tube 12; the input end of the voltage-stabilizing power supply circuit is connected with the positive end of a power supply 1, the output end of the voltage-stabilizing power supply circuit is respectively connected with the power supply end of a CPU microcomputer board 16 and the input end of a driver control circuit, the output end of the driver control circuit is connected with the signal input end of the CPU microcomputer board, the IGBT drive output end G of the CPU microcomputer board is connected with 6 IGBT grids of an IGBT three-phase inverter circuit, a chopping signal end 24 of the CPU microcomputer board is connected with the grid of a power switch tube 12 in a brake circuit, and a resistor 13 of the brake circuit is connected.

The working principle of the invention is as follows: the power supply 21C of the rated voltage of the overhead line to the ground is connected with the positive end through one end of the automatic switch 11, in the current limiting circuit formed by the parallel connection of the current limiting resistor 14 and the direct current contactor 15, the other end of the current limiting resistor 14 and the direct current contactor 15 after the parallel connection is connected with the positive end of the filter capacitor in the filter circuit. The output end of the filter circuit is connected to the collectors of three groups of double-tube type IGBT upper bridge plates in the IGBT three-phase inverter circuit, the emitters of the three groups of IGBT lower bridge plates are connected to the negative end of the power supply 1, and the IGBT driving output end of the CPU microcomputer plate is connected to 6 IGBT grids of the IGBT three-phase inverter circuit; the control power supply of the CPU microcomputer board and the driver control circuit is supplied by a voltage stabilizing power circuit. The stabilized voltage power supply circuit mainly converts unstable network voltage into 24V required by control appliances and 15V required by IGBTs through DC/DC. The driver control circuit is a command line for a driver to operate the locomotive, the driver is connected to a signal input 23 interface of the CPU microcomputer board through a direction switch, the output of the CPU microcomputer board is connected to 6 IGBT grids in the IGBT three-phase inverter circuit, and the forward and reverse rotation of the motor is controlled by changing the on-off sequence of the IGBTs, so that the locomotive is moved forward or backward; a speed regulation handle in the driver control circuit outputs 0-5V analog signals to a speed regulation input end of a CPU microcomputer board through a rotary transformer, and finally the IGBT three-phase inverter circuit outputs corresponding frequency signals to an alternating current motor through analog/digital conversion so as to realize the change of the rotating speed of the electric locomotive.

Locomotive braking is realized by a braking circuit which is divided into energy regenerative braking and energy consumption braking, and when the locomotive decelerates, the rotating speed of the motor exceeds the synchronous rotating speed to enter a regenerative braking state. When no other locomotive consumes the energy source, the bus voltage will continuously rise, when the bus voltage detection circuit reaches the set value, the signal is input into the CPU microcomputer board, so as to drive the power switch tube 12 to be conducted, and at the moment, the motor enters the energy consumption brake on the resistor 13 from the energy source regenerative brake.