CN202178738U - Device capable of weakening impact upon electrical network by starting of PET-CT - Google Patents

Abstract

The utility model relates to a device capable of weakening impact upon an electrical network by starting of a PET-CT (Position Emission Computed Tomography). The device comprises a rectifier bridge, an inverter and a PET-CT scan frame driving motor. The input terminal of the rectifier bridge is connected with an alternating current power source, and the output terminal of the rectifier bridge is connected with a filtering capacitor. The inverter is connected with the PET-CT scan frame driving motor. The device also comprises a PFC circuit. The input terminal of the PFC circuit is connected with the filtering capacitor, and the output terminal of the PFC circuit is connected with the inverter. A local energy storage element is disposed between the output terminal of the PFC circuit and the inverter. The local energy storage element is connected with the output terminal of the PFC circuit in a parallel manner, and is connected with the inverter in a parallel manner. The device of the utility model allows electric energy needed for starting of a PET-CT scan frame to be satisfied, helps to minimize demands of the capacity of an electrical network during starting of the PET-CT scan frame, and enables impact upon the electrical network to be weakened.

Description

A kind of PET-CT that weakens starts the device that electrical network is impacted

Technical field

The utility model relates to the PET-CT field of electric drive, particularly relates to a kind of PET-CT of weakening and starts the device that electrical network is impacted.

Background technology

Positron computer x-ray tomography (PET-CT:Positron Emission Computed Tomography; Hereinafter to be referred as PET-CT) be the 3-dimensional image guiding tool; Under image-guided, playing the part of important role in the innovation of radiotherapy notion and the application; PET-CT has outstanding information gathering ability, has also caused PET-CT scanning gantry overweight simultaneously; Make PET-CT start, the power difference of demand is bigger during operate as normal, force electrical network to supply with big electric current and cause pressure drop of grid to increase; The impact that when PET-CT starts electrical network is caused is excessive, has increased the requirement of PET-CT to net capacity.

Summary of the invention

The utility model technical problem to be solved provides a kind of PET-CT of weakening and starts the device that electrical network is impacted, and when CT starts, reduces the impact that electrical network is caused.

The utility model solves the technical scheme that its technical problem adopted: provide a kind of PET-CT of weakening to start the device that electrical network is impacted, comprise rectifier bridge, inverter and PET-CT scanning gantry drive motors; Said rectifier bridge input is connected with AC power; Output is connected with filter capacitor, and said inverter links to each other with PET-CT scanning gantry drive motors, and said device also comprises pfc circuit; The input of said pfc circuit links to each other with filter capacitor, and output links to each other with inverter; Also be provided with local energy-storage travelling wave tube between the output of said pfc circuit and the inverter, said local energy-storage travelling wave tube is connected in parallel on the output of pfc circuit, and parallelly connected with inverter.

Said local energy-storage travelling wave tube is super capacitor or storage battery.

Said AC power is the AC power of 220V.

Beneficial effect

Owing to adopted above-mentioned technical scheme; The utility model compared with prior art has following advantage and good effect: the utility model adopts local energy-storage travelling wave tube to be installed between pfc circuit and the inverter, in the scanning gantry start-up course; Through pfc circuit and local energy-storage travelling wave tube discharge while drive motors; Required electric energy when starting to satisfy the PET-CT scanning gantry has reduced when the PET-CT scanning gantry starts the demand of net capacity has been weakened the impact to electrical network.

Description of drawings

Fig. 1 is the PET-CT scanning gantry driven by power structural representation of the utility model;

Fig. 2 is the working cycle diagram of scanning gantry drive motors;

Fig. 3 is the power-actuated structural representation of PET-CT scanning gantry of the utility model embodiment 1;

Fig. 4 is the power-actuated structural representation of PET-CT scanning gantry of the utility model embodiment 2.

Embodiment

Below in conjunction with specific embodiment, further set forth the utility model.Should be understood that these embodiment only to be used to the utility model is described and be not used in the restriction the utility model scope.Should be understood that in addition those skilled in the art can do various changes or modification to the utility model after the content of having read the utility model instruction, these equivalent form of values fall within the application's appended claims institute restricted portion equally.

The execution mode of the utility model relates to a kind of PET-CT of weakening and starts the device that electrical network is impacted, and is as shown in Figure 1, comprises rectifier bridge 1, inverter 2 and PET-CT scanning gantry drive motors 3; Said rectifier bridge 1 input is connected with AC power 4; Output is connected with filter capacitor 5, and said inverter 2 links to each other with PET-CT scanning gantry drive motors 3, and said device also comprises pfc circuit 6; The input of said pfc circuit 6 links to each other with filter capacitor 5, and output links to each other with inverter 2; Also be provided with local energy-storage travelling wave tube 7 between the output of said pfc circuit 6 and the inverter 2, said local energy-storage travelling wave tube 7 is connected in parallel on the output of pfc circuit 6, and parallelly connected with inverter 2.

When start preheating PET-CT scanning gantry, through pfc circuit to the energy storage of charging of local energy-storage travelling wave tube.Start PET-CT scanning gantry drive motors, because scanning gantry carries many samplers, make that the moment of inertia of scanning gantry is very big, the PET-CT scanning gantry is very high to the power requirement of its drive motors when starting.The utility model is through pfc circuit and utilize local energy-storage travelling wave tube discharge, gives the power supply of PET-CT scanning gantry drive motors simultaneously, quickens the startup of PET-CT scanning gantry drive motors.After treating the normal operation of PET-CT scanning gantry, its drive motors rotating speed tends towards stability; This moment, pfc circuit can directly drive PET-CT scanning gantry drive motors through inverter, gave local energy-storage travelling wave tube charging simultaneously.

This shows; The utility model is on the basis that does not change original PET-CT scanning gantry performance, structure, and through adding a local energy-storage travelling wave tube (for example super capacitor or storage battery), pruning through this part energy-storage travelling wave tube starts the spike of scanning machine posture power demand; Improve driving power power output capacity when PET-CT starts; Promptly in the scanning gantry start-up course, through pfc circuit and the discharge of local energy-storage travelling wave tube drive motors simultaneously, required electric energy when starting to satisfy the PET-CT scanning gantry; To the demand of net capacity, weakened impact when having reduced the startup of PET-CT scanning gantry to electrical network.

With two embodiment the utility model is further described below.

Embodiment 1: a kind of weakening PET-CT based on super capacitor starts the device that electrical network is impacted, and is as shown in Figure 3, comprises rectifier bridge 1, inverter 2 and PET-CT scanning gantry drive motors 3; Said rectifier bridge 1 input is connected with 220V AC power 4; Output is connected with filter capacitor 5, and said inverter 2 links to each other with PET-CT scanning gantry drive motors 3, and said device also comprises pfc circuit 6; The input of said pfc circuit 6 links to each other with filter capacitor 5, and output links to each other with inverter 2; Also be provided with super capacitor 7-1 between the output of said pfc circuit 6 and the inverter 2, said super capacitor 7-1 is connected in parallel on the output of pfc circuit 6, and simultaneously parallelly connected with inverter 2.

Fig. 2 adopts the working cycle diagram of the scanning gantry drive motors behind the utility model; The Discovery ST CT that produces with U.S. GE company is an objective for implementation, learns that Discovery ST PET-CT scanning gantry drive motors is in one-period, among the figure; Heavy line is the power output of inverter; Fine line is a motor working current, and dotted line is the electrical network input current, and the square frame line is the magnitude of voltage of super capacitor.Be t start-up time ₁, starting power is p ₁, promptly the PET-CT scanning gantry startup stage; Parallel-adder settle-out time is t ₂, stable operation power is p ₂, i.e. PET-CT scanning gantry stable operation stage; The regenerative braking time is t ₃, regenerative brake power is p ₃, i.e. PET-CT scanning gantry regenerative braking stage; Downtime that powers on is t ₄, powering on and shutting down power is p ₄(supposing to be close to 0), i.e. PET-CT scanning gantry idle stop stage.Can find out that from figure PET-CT scanning gantry drive motors operating current is greater than the electrical network input current startup stage of the PET-CT scanning gantry.

Super capacitor is connected between pfc circuit and the inverter; Discharge through super capacitor; Assist pfc circuit to start the PET-CT scanning gantry; To remedy the not enough drawback of pfc circuit outputting power, make the PET-CT scanning gantry more steadily, start rapidly, from Fig. 2 can know super capacitor stored voltage value and electrical network input current stack back just and the operating current of motor identical each other.Wherein, the major parameter of super capacitor and pfc circuit can be obtained according to following equality.

$p_1{\mathrm{<figure-callout\; id="1"\; label="t"\; filenames="HDA0000082916030000011.png,HDA0000082916030000021.png"\; state="\{\{state\}\}">t</figure-callout>}}_1=(0.5*C*{\mathrm{<figure-callout\; id="2"\; label="U"\; filenames="HDA0000082916030000022.png"\; state="\{\{state\}\}">U</figure-callout>}}_2^2-0.5*C*{\mathrm{<figure-callout\; id="1"\; label="U"\; filenames="HDA0000082916030000011.png,HDA0000082916030000021.png"\; state="\{\{state\}\}">U</figure-callout>}}_1^2)*{\mathrm{\&eta;}}_1+P_{\mathrm{PFC}}*{\mathrm{<figure-callout\; id="1"\; label="t"\; filenames="HDA0000082916030000011.png,HDA0000082916030000021.png"\; state="\{\{state\}\}">t</figure-callout>}}_1$

E _all＝p ₁t ₁+p ₂t ₂-p ₃t ₃

$P_{\mathrm{PFC}}=\frac{E_{\mathrm{all}}}{{\mathrm{<figure-callout\; id="1"\; label="t"\; filenames="HDA0000082916030000011.png,HDA0000082916030000021.png"\; state="\{\{state\}\}">t</figure-callout>}}_1+{\mathrm{<figure-callout\; id="2"\; label="t"\; filenames="HDA0000082916030000022.png"\; state="\{\{state\}\}">t</figure-callout>}}_2+{\mathrm{<figure-callout\; id="3"\; label="t"\; filenames="HDA0000082916030000011.png,HDA0000082916030000021.png"\; state="\{\{state\}\}">t</figure-callout>}}_3+{\mathrm{<figure-callout\; id="4"\; label="t"\; filenames="HDA0000082916030000011.png,HDA0000082916030000022.png"\; state="\{\{state\}\}">t</figure-callout>}}_4}$

In the following formula, C is the rated capacity of super capacitor; η ₁Efficiency for charge-discharge for super capacitor; E _AllBe scanning gantry required gross energy in a complete work period; P _PFCFor scanning gantry in a complete work period, the average output power of pfc circuit; U ₁, U ₂Voltage when being followed successively by the beginning voltage of electric capacity in a work period and starting end.In practical application, for shortening the start preheating stand-by period or satisfying the power demand under the idle machine state, the average output power P of pfc circuit _PFCCan elect bigger numerical value as.

Embodiment 2: a kind of weakening PET-CT based on storage battery starts the device that electrical network is impacted, and is as shown in Figure 4, comprises rectifier bridge 1, inverter 2 and PET-CT scanning gantry drive motors 3; Said rectifier bridge 1 input is connected with 220V AC power 4; Output is connected with filter capacitor 5, and said inverter 2 links to each other with PET-CT scanning gantry drive motors 3, and said device also comprises pfc circuit 6; The input of said pfc circuit 6 links to each other with filter capacitor 5, and output links to each other with inverter 2; Also be provided with storage battery 7-2 between the output of said pfc circuit 6 and the inverter 2, said storage battery 7-2 is connected in parallel on the output of pfc circuit 6, and simultaneously parallelly connected with inverter 2.

Fig. 2 adopts the working cycle diagram of the scanning gantry drive motors behind the utility model; The Discovery ST CT that produces with U.S. GE company is an objective for implementation, learns that Discovery ST PET-CT scanning gantry drive motors is in one-period, among the figure; Heavy line is the power output of inverter; Fine line is a motor working current, and dotted line is the electrical network input current, and the square frame line is the dump energy of storage battery.Be t start-up time ₁, starting power is p ₁, promptly the PET-CT scanning gantry startup stage; Parallel-adder settle-out time is t ₂, stable operation power is p ₂, i.e. PET-CT scanning gantry stable operation stage; The regenerative braking time is t ₃, regenerative brake power is p ₃, i.e. PET-CT scanning gantry regenerative braking stage; Downtime that powers on is t ₄, powering on and shutting down power is p ₄(supposing to be close to 0), i.e. PET-CT scanning gantry idle stop stage.Can find out that from figure PET-CT scanning gantry drive motors operating current is greater than the electrical network input current startup stage of the PET-CT scanning gantry.

Storage battery is connected between pfc circuit and the inverter; Discharge through storage battery 5; Assist pfc circuit to start the PET-CT scanning gantry; To remedy the not enough drawback of pfc circuit outputting power, make the PET-CT scanning gantry more steadily, start rapidly, the dump energy that can know storage battery from Fig. 2 and electrical network input current stack back just and the operating current of motor identical each other.The major parameter of storage battery and pfc circuit can be obtained according to following equality.

p ₁*t ₁＝U*C _n*η ₁+P _PFC*t ₁

E _all＝p ₁t ₁+p ₂t ₂-p ₃t ₃

$P_{\mathrm{PFC}}=\frac{E_{\mathrm{all}}}{{\mathrm{<figure-callout\; id="1"\; label="t"\; filenames="HDA0000082916030000011.png,HDA0000082916030000021.png"\; state="\{\{state\}\}">t</figure-callout>}}_1+{\mathrm{<figure-callout\; id="2"\; label="t"\; filenames="HDA0000082916030000022.png"\; state="\{\{state\}\}">t</figure-callout>}}_2+{\mathrm{<figure-callout\; id="3"\; label="t"\; filenames="HDA0000082916030000011.png,HDA0000082916030000021.png"\; state="\{\{state\}\}">t</figure-callout>}}_3+{\mathrm{<figure-callout\; id="4"\; label="t"\; filenames="HDA0000082916030000011.png,HDA0000082916030000022.png"\; state="\{\{state\}\}">t</figure-callout>}}_4}$

In the following formula, U is the output voltage of storage battery; C _nBe battery rating; η ₁Be charging and discharging of accumulator efficient; E _AllBe scanning gantry required gross energy in a complete work period; P _PFCFor scanning gantry in a complete work period, the average output power of pfc circuit.

Claims (3)

1. one kind weakens the PET-CT startup to the device that electrical network impacts, and comprises rectifier bridge (1), inverter (2) and PET-CT scanning gantry drive motors (3); Said rectifier bridge (1) input is connected with AC power (4); Output is connected with filter capacitor (5); Said inverter (2) links to each other with PET-CT scanning gantry drive motors (3), it is characterized in that, said device also comprises pfc circuit (6); The input of said pfc circuit (6) links to each other with filter capacitor (5), and output links to each other with inverter (2); Also be provided with local energy-storage travelling wave tube (7) between the output of said pfc circuit (6) and the inverter (2), said local energy-storage travelling wave tube (7) is connected in parallel on the output of pfc circuit (6), and parallelly connected with inverter (2).

2. weakening PET-CT according to claim 1 starts the device that electrical network is impacted, and it is characterized in that said local energy-storage travelling wave tube (7) is super capacitor (7-1) or storage battery (7-2).

3. weakening PET-CT according to claim 1 starts the device that electrical network is impacted, and it is characterized in that said AC power (4) is the AC power of 220V.

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